nanoindenter operating procedures - university of...

UW Nanomech Lab 1

Rev. 1: Jane, Jennie, and Gabe 10/29/2008

Rev. 2: Gabe 10/7/2010 (Added top-down optics and motorized stage)

Hysitron UBi1 Nanoindenter Operating Procedures

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If at any time you are unsure about something, encounter a problem, or

require the use of an indenter tip that is not currently mounted, please

contact the system administrator for assistance.

The current system administrator is Gabe

Email: [email protected] Phone: (707) 483 - 0292

Table of Contents

WORDS OF CAUTION .................................................................................................................... 3

PREPARING THE HARDWARE AND YOUR SAMPLES ...................................................................... 4

FIRST STEPS ................................................................................................................................... 5

Z-AXIS CALIBRATION ...................................................................................................................... 6

DEFINING SAMPLES ....................................................................................................................... 8

IMAGING ..................................................................................................................................... 10

INDENTATION .............................................................................................................................. 12

SETTING UP THE LOAD FUNCTION AND PERFORMING A SINGLE INDENT .............................................................. 12

PIEZO AUTOMATION .................................................................................................................................. 15

SETTING UP AN AUTOMATED METHOD FOR INDENTATION ................................................................................ 17

INDENT ANALYSIS ...................................................................................................................................... 22

SCRATCH TESTING ....................................................................................................................... 24

X-AXIS CALIBRATION .................................................................................................................................. 24

SETTING UP A SCRATCH LOAD FUNCTION AND PERFORMING A SCRATCH ............................................................. 26

AUTOMATED SCRATCHING .......................................................................................................................... 30

SHUTDOWN PROCEDURES .......................................................................................................... 31

TROUBLE SHOOTING ................................................................................................................... 32

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Words of Caution

1. Do not leave the lamp on when it is not needed.

2. Always keep an eye on the tip position in the acoustic chamber as you move around with

the x-y-z stage controls. Make sure that the tip will not crash into anything.

3. Tested surfaces have to be smooth enough or the tip can be damaged easily and you will

get poor indentation results

4. Do not use computer while it is busy performing a function such as an approach or during

any sort of automated testing. Doing so may cause the computer to freeze.

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Preparing the hardware and your samples

1. If the machine is totally off, do not attempt to turn it on. Contact the system administrator.

2. Consult the log book first to see if anyone else is currently using the indenter. If not, write

your name, the date, and the starting time for your testing into the book.

3. Check your samples to make sure they are clean, smooth, and not tilted. When performing

a session with multiple samples, only proceed if they are around the same height (less than

1 mm difference). If they are significantly different in height, analyze them one at a time.

4. Open the Acoustic Enclosure and put the sample(s) onto the stage.

The sample stage is magnetic. It is recommended that you mount by gluing a magnet

to the bottom of your samples. Simply taping samples to the surface can be done, but

only if absolutely necessary. If this is done, the bottom of the sample must be flush

with sample stage (eg. no double stick tape).

CAUTION: Do not touch the transducer assembly or the indenter tip while mounting

the samples

5. Look on the main control unit and check that the knobs have the following settings:

Low pass filter: 1000 Hz

Displacement Gain: 100

Microscope Feedback: 1000

Display Gain: 100

6. Zero the front panel meter by manually adjusting the coarse knob to less than 0.01.

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First steps

1. Start from the windows “Start” menu and open the “TriboScan” Program. The program

takes a few minutes to initialize as it zeroes the stages. Once started, the main window

should look similar to this:

2. To create a workspace, go to the top left of the screen and click the down arrow next to

“Default workspace.” Select “New Workspace” and save as any name you desire.

3. Turn on the fiber optic light next the UBi1 computer (the V-lux 1000 unit) to

illuminate the stage.

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Z-axis Calibration

1. Z-axis calibration should be done at the beginning of each session. Go to the

“calibration tab” in the main window and click on the “system calibrations” sub tab.

Location of microscope feedback software setting and calibrate execution button

2. Adjust the microscope gain to 100 in both the software and hardware. This MUST be

done for proper calibration.

Software: In the calibration tab, go to the “system calibration” sub tab and look at

the “System Setup – Front Panel Settings.” Change the “Microscope Feedback

Gain” to 100.

Hardware: Physically adjust the Microscope Feedback Gain to 100 on the main

control unit with the knob.

3. Now look at where it says “Transducer Calibrations.” Under indentation axis, click

“Calibrate”

Cal Air Indent button

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4. The software will switch to the Load Function tab where you can click “Cal Air

Indent”

5. A dialog box will ask “Is the load function set up correctly”, click “Start”

6. A dialog box will ask “Re-zero front panel meter on TriboScope controller.” Re-zero

the controller manually on the main control unit.

7. A dialog box will ask to set the Displacement Gain to 100 and microscope feedback

gain to 100. Both these should already be set correctly from earlier, but double check

anyways. Click “OK” and the z-axis calibration will run.

8. Once the test is finished, it will ask if you want to keep the air calibration data, click

“Yes”

9. A dialog box will ask to re-zero the controller once again and return the microscope

feedback gain to 1000. Perform both of these tasks on the main control unit, then click

“OK”

10. A graph will appear with a fitted function of the Electrostatic Force Constant as a

function of displacement. If the fit is reasonable such as the picture below, you can

close the curve fit plot window. If the fit is lousy, double check that the microscope

feedback and displacement gain were set to 100 in both the software and hardware

controls during the calibration. Redo the z-axis calibration and if the result is still poor,


Example ESF vs Displacement Plot

11. Go back to the calibration tab and the system calibrations sub tab. Change the

microscope feedback gain back to 1000 under the front panel settings.

CAUTION: It is very important to double check that the microscope feedback gain has

been changed back to the value of 1000 in both the software and hardware before

proceeding. (Steps 9 and 11)

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Defining Samples

1. Go to the “Sample Navigation” tab of the software. It will bring you back to the display

seen when the software was first started. Stage controls are in the top right quadrant of

the screen.

Stage controls and X-Y lock toggle

2. By default, the x-y stages are locked before any samples are defined. Click the bubble

next to “X-Y Safety DISABLED” so that it turns red to unlock x-y movement.

3. The 3-axis movements are done by clicking and holding various parts of the blue

reticule graphic. The separated column on the left is for Z-axis control. For example,

clicking and holding position “6” will lower the Z-axis at the fastest speed. To lower at

a slower speed, click closer to the bolded blue median line. To raise the stage, click

above the median line.

Stage controls guide

4. X-Y controls are similarly done by clicking and holding various positions on the X-Y

diagram. For example, holding position 2 will increase the Y position at fastest speed.

Holding position “5” will increase X position at slow speed.

5. It is now time to define your sample(s). While looking into the acoustic chamber, adjust

the x-y position so that the lighted area is centered over a corner of the sample. Next,

lower the z-axis until the corner and a flat portion of the sample area are in optical

focus. You may need to adjust the x-y position while doing this.

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CAUTION: The bottom stage comes into focus at ~32 mm in Z-height, never go above

this value. Use your sample thickness to estimate when your sample should come into

focus. For example, a 1 mm thick sample will come into focus at ~31 mm. The focus

point is always several millimeters before the point of tip contact. Keep a close eye on

the tip as it descends and make sure that it does not crash into the stage or sample

surface. Do not work with samples that have a large height difference to one another

as the transducer and tip could easily bump into the thicker sample as it tries to focus

onto the thinner one.

6. With the corner in focus, click on “New sample” at the sample controls located in the

bottom left quadrant of the screen and name the sample. Then click on “Pos. Add” so

that the software saves the location of this corner.

New sample and Pos. Add button locations

7. Now, navigate to another corner of the sample using the x-y controls. Re-focus the

image at the next corner (if necessary) by adjusting the z-axis slightly. With the next

corner in focus, click “Pos. Add” once again.

8. Repeat step 7 until all corners have been defined.

9. You should now see a colored outline of your sample shape next to the navigation

window where the stage overview is displayed. It will also be seen in the samples

control region next to the “Pos. add” and “New Sample” buttons.

10. Repeat steps 5-9 until all samples have been defined.

11. Once all samples are defined, it is easy to navigate around the samples by right clicking

on either the actual live image, the stage overview (above the x-y safety buttons), or the

sample window in the bottom left.

12. If you will be performing automated tests on all samples during this session without

imaging the surfaces, navigate to a spot close to the center of each sample (by right

clicking or by using the x-y controls) and perform a quick approach on each. This is

necessary to determine the exact Z-height of each sample before automation. Each

quick approach will take several minutes. Once the quick approaches are done, skip

ahead to the “Setting up an automated method” section.

13. If you will be imaging the surface first before performing tests, a quick approach is not

necessary at this time. It will be performed in the next section.

14. Now is a good time to save your workspace. This is done by using the drop down menu

in the upper-left. It is the same one that was used earlier to create a workspace, except

this time, select “Save Workspace.”

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Imaging

1. From the “Sample Navigation” tab of the software, navigate to a spot on the sample

where imaging is desired by using the x-y controls or by right-clicking.

2. Switch to the “Imaging” tab of the software

3. Turn off the fiber optic light now since it is not necessary for SPM imaging.

4. Look at the imaging controls. Set the appropriate parameters you would like. The

default values work well for most samples. They are:

Scan Rate: 1 Hz,

Tip Velocity: 20 µm/s

Scan Size: 10 µm

Setpoint: 2 µN

Integral Gain: 496

Vertical Scanning: Off (unchecked)

Imaging controls settings

5. Re-zero the front panel manually by adjusting the coarse knob to a reading < 0.012

6. Approach the surface by clicking the “approach surface” button on the imaging toolbar

in the upper left. It is found directly below the word “Engage.”

Image control toolbar - approach button

7. Once the sample has been approached, click the green “Go” button on the image

toolbar to start scanning.

8. The four images should now start updating as the scan progresses. The images on the

left side are topographical images in the forwards (top) and backwards (bottom)

directions. The images on the right are gradient images in the forwards and backwards

directions.

9. The lower right quadrant displays the image data regarding the current scan lines and

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height histograms. Adjusting values in here can make the SPM images look much

better by changing the color mapping. The easiest option is to hit the “Auto” button.

However sometimes it may need manual adjustment by using the blue sliders.

Scanning data display

10. If you wish to save a scan image, in the imaging tab, go to the “Image” drop down

menu and click on “Capture File Name.” Select the folder where you want to save

your image, write the file name, and click “ok”. During the scan, click on the camera

icon on the image toolbar next to the “stop” button. The image will be automatically

saved to the folder you selected once the scanner has completed the next full pass over

the scanning area. You can analyze the saved images afterwards with the software

“ Triboview”

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Indentation

Setting up the Load Function and performing a Single Indent

1. While imaging the surface, on the image toolbar, there is an option to perform a single

indentation. However, before indenting, there are a few things that need to be setup.

2. Make sure that the “Mode” at the top of the screen is set to “Indentation”

3. You need to setup the loading parameters for the indentation. Switch to the “Load

Function” tab in the software and make sure you are on the “Quasi” sub tab.

Load Function tab with default loading criteria

4. The default load function is an open loop indent with a 10 second load/unload time. In

this configuration, there is no force feedback therefore this load function is not

commonly used.

5. Many former users of the indenter have adopted a 10:5:10 load control function for use

with their characterization. This specifies a load control indent with a 10s loading time,

5s hold time at maximum load, and a 10s unloading time. This load function is highly

recommended for all characterization purposes.

6. To change the load function from the default settings, go to the “File” menu and click

on “Open Load Function.” Click and load the “Load_Control_10s_5s_10s.ldf” file to

load the 10:5:10 function.

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Standard load function with important parameters circled

7. After loading the function, the parameters that may require some attention here are:

Pre-Load: This should be equal to or greater than the scanning setpoint.

Default is 2µN

Lift Height: This is the distance the tip is raised over the surface before the

indentation begins. This should be equal to or greater than the surface

roughness. Default is 10 nm and that value works fine for most polished

samples where roughness is typically very low.

Peak force: Set the maximum indentation force.

CAUTION: Do not change any of the other parameters unless you have permission to!

8. If your work requires the use of a specific load function, a custom load function can be

created by adding segments and manipulating the segment parameters. If this will be

done, please let the system administrator know so that the function can be checked to

be within the limitations of the instrument.

9. Once you have the load function set up, switch back to the “Imaging” tab of the software.

10. Find a place on the sample that you would like to indent on and center it in the image

area.

11. On the image toolbar, click on the “Test” button to start indentation.

Image control toolbar – Test button

12. A dialog box will ask if the load function is setup correctly. Click “OK” to proceed

with the indentation. While the indent is running a real time monitor window show

you the progress of the indent. This will be in the form of a red line “traced” with blue

dots. The blue dots are real time data coming back, and the red line is the intended load

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function. If the blue dots do not follow the red line, than you need to adjust the load

control feedback gains until they follow the red line as closely as possible. Please

contact the system administrator for assistance with this problem.

Real-time display during indentation

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Piezo Automation

1. To properly characterize the properties of a sample, multiple indents with different

forces are usually necessary. Piezo automation performs an automated set of indents

with varying force on the imaged surface.

2. The first step is to find a suitable area for the automated indents. Ideally, the entire

imaging area should be smooth and as flat as possible.

3. Next, switch to the “Load Function” tab of the software and make sure that the load

function is setup properly for the automated indentations that will be performed. Do

not worry about the “Peak Force” setting for now as Piezo Automation will change

that accordingly.

4. Switch to the “Automation” tab of the software and click on the “Piezo Automation”

sub tab. On this screen, there are several important selections to make:

Save scan: scan and save the imaging area after the indent array is complete. This

is suggested.

Stay in Contact: Set whether the tip will stay in contact with the surface after the

array is complete. It is highly suggested that you do not do this since you will

most likely be away from the machine during the automation process.

Piezo automation settings

5. Next, you must choose the number of indents and spacing between the indents in both

the x and y directions. It is suggested that you make the spacing between the indents

several times the size of the indent.

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Piezo automation settings

6. It is suggested that the time delays Before 1st Indent be set to 180 sec, and Between

Indents to 120 sec.

7. Once everything is setup, click on “Run Piezo Automation” to start the indent array.

You will be asked if the load function is set up properly, click “yes.” You will then be

asked for a directory to store the files. A third prompt will ask what the filenames will

be. Type in a descriptive name that includes the tip, sample, and loading range. For

example: Berk_Al_1000uN_500uN.

8. The final menu allows you to control the loading range. The top box shows the number

of indents in the array. The left box allows you to choose the maximum load of the

first indent, and the right box allows you to choose the maximum load of the last

indent. The bottom box shows you the change in maximum load between each indent.

See the pictures below. It is recommended that you start with the highest load first and

end with the lowest. After you have chosen the appropriate values click continue to

start the array.

Load selection for piezo automation test

9. As a general rule, always watch the first process in an automation before leaving the

computer to make sure everything goes okay.

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Setting up an automated Method for Indentation

1. If you have multiple samples mounted and/or are interested in characterizing a single

sample at multiple locations, using an automated “Method” is much more flexible than

the “Piezo automation” function. The main drawback is the lack of sample imaging

prior to the indentation process therefore this is only recommended for samples with

low surface roughness and exceptional surface quality.

2. Methods are defined by patterns, groups, and positions. A “Group” is a set of user

defined “positions” on the sample surface. At each position in the group, an

indentation “pattern” will be performed. Each method can only have one group and

one pattern associated with it. However Methods can be chained to each other to start

successively giving the user the ability to perform different types of indentation arrays

at different areas.

Even if the same indentation pattern will be used on all samples and at all locations, it

is still recommended that each sample has its own Method setup.

3. “Methods” can only be performed on defined sample areas and samples where a

“quick approach” has been executed. Make sure these tasks have been complete before

proceeding.

4. Switch to the “Automation” tab of the software and click on the “Methods” sub tab.

5. Create a method by clicking on “New Method” and name it.

6. A dialog box saying “The pattern in method <method name> is not set” may come up.

Just click “OK” as the pattern will be setup later on.

7. Change the “Base File Name” and “Drive & Directory” to an appropriate filename and

location that you want to save the data to. Make sure that the Method type is “Indent.”

Methods tab – Region to create a new method circled

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8. Next click on the “Patterns” sub tab found on the far right side next to the “New

Method” button.

9. You can now setup the indentation array that will be followed. The most common is to

use a grid (just like the piezo automation test), but other choices are available such as

the “Circle” for a circular pattern. Click on either one and set the appropriate spacing

parameters between indents. Then click “Create” to save the pattern while naming it

accordingly.

Patterns setup

10. Next click on the “Position” sub tab found directly underneath the “Patterns” sub tab.

Here you will define the positions where the indentation pattern from above will be

performed. Start by clicking “New” and name the group of positions. Navigate to a

position where you would like to indent by right clicking in the sample window in the

bottom left or by using the x-y controls. Once the position is centered in the live image

window, click on “Add above” and the position will be saved. Navigate to another

position where you would like to perform the indentation pattern and this time click

either “Add Above” or “Add Below.” If “Add Above” is selected, this position will be

executed prior to the first one. The opposite is true if “Add below” is selected.

Continue adding positions until all desired positions for indentation have been saved.

Groups and Positions setup region

11. Go back to the “Setup” sub tab found directly above the “Patterns” sub tab. The

patterns and groups created by the user need to be associated with the method. Go to

the “Patterns” subsection and select the saved pattern using the up and down arrows.

The pattern should be displayed on the right. It is not recommended to “Maintain

contact within patterns.”

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Patterns subsection

12. Now go to the “Positions” subsection and select the bubble “Indent pattern using

positions in.” Select the correct group name using the up and down arrows.

Positions subsection

13. Click on “Load Function” and the “Load Function Setup” window will appear. Click

on “Select load function” and select the standard “Load_Control_10s_5s_10s.ldf” file

or a custom function file that you have saved. Bubble in the option “Adjust peak load

while keeping segment times constant.” Adjust the start and ending load to the desired

values. It is recommended that the highest load is first and the lowest load is last. Click

“OK” when done with these parameters. The correct loading task at each position

should now be defined in the text under “Load Function.” If it is incorrect, go back

into the “Load Function Setup” window and adjust the values accordingly.

CAUTION: Do not select any of the other bubbles in the “Load Function Setup”

window.

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Load function button and Load function setup screen

14. If you want to save SPM images of the surfaces before and after each test, click on the

“Imaging” button. This will bring up the “Imaging Setup” window. Click on the “On”

checkboxes to enable “Pre method imaging” and/or “Post method imaging.” Bubble in

“imaging applied to each event in a method.” The scanning parameters will not need to

be altered since methods should only be applied to samples with good surface quality!

Close the “Imaging Setup Window” when finished.

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Imaging button and Imaging setup screen

15. If you are working with multiple samples, repeat steps 5-14 to create a separate

method for each sample.

16. Once methods have been setup for each sample, you can chain the methods together so

that they start successively. To do this, go to the bottom of the screen where it says

“When method is complete” and check the box labeled “Perform Method.” In the area

to the right, select the name of the 2nd

method to start. Now go back to the top of the

screen where it says “Method Name” and select the name of the 2nd

method. Go down

to the bottom and once again check the box to perform another method and select the

3rd

method. Continue doing this until all methods have been chained together.

Selection for chaining methods together

17. Click “Start Method” to begin the automation process.



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Indent Analysis

1. The indent Analysis window will open at the end of an indent, or go to “Analysis” tab

in the software.

2. If your indentation data did not load automatically, click the “Open” button on the

analysis toolbar and find the file where the data was saved.

Analysis toolbar – Open button

3. Ensure that the “Unloading Segment is correct in the parameters listed on the right side.

For usual cases, the unloading segment is set to 3.

4. Click “Execute Fit” and the hardness and modulus numbers will be generated and

displayed at the top right of the screen.

Analysis tab, unloading segment selection and execute fit button

5. To plot multiple curves at once, go analysis toolbar and click the “Plot multiple

curves” button. When the next window comes up, click on “Add Curves.” When the

“Select Data Files to Plot” window appears, highlight the desired curves, click “Add”,

and then click “OK”. The curves will now be plotted.

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Multiple curve plotting and analysis

6. To analyze multiple curves, in the multiple curves plot, click “Mult. Cur. Ana.” You

will then be asked to name the file to save the data into. Name the file and continue.

The multiple curve analysis window opens and you will have the option of loading

other data sets to compare, see picture below.

Modulus and Hardness data display window

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Scratch Testing

X-axis calibration

1. Start by switching the software mode to “Scratch” near the top center of the screen.

Switching to Scratch Mode

2. Just like for Z-axis testing, we need to calibrate the X-axis before performing any

scratches. Click to the “Calibration” tab of the software and go to the “System

Calibrations” sub tab.

3. Make sure that the Scratch Axis transducer constants are the same as the values

provided by the hysitron constants sheet. The values are:

Load Scale Factor: 3.0650 mV/mg

Displacement Scale Factor: 107.2500 mV/µm

Imaging Position: -10.0000 µm

Electrostatic Force Constant: 0.022 µN/V2

Plate Spacing: 98.143 µm

Displacement Offset: -0.821 µm

The calibration constants sheet can be found in the front sleeve of the logbook binder.

Scratch Calibration Page. Places to adjust the constants circled

4. Once all the constants have been entered, click on “Calibrate” and the software will

switch to the “Load Function” tab. Make sure that the “Scratch Axis Calibration.scf”

file is loaded and displayed in the top left of the screen under the “File” menu.

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Scratch calibration load function page. Filename position circled

5. Click on “Cal Air Scratch” to begin the calibration process. A real-time plot should

pop up showing the tip progress through the scratch from -5 to 5 µm. At the end of the

scratch, a popup box will ask if you want to keep the calibration data, click “yes.”

6. After clicking yes, 4 graphs will display. The one of importance is the Lateral Force vs

Time plot. Make sure that all of these values fall within a 10 µN range such as the

figure below. If they do not, then go back to the calibration page, double check the

constants, and repeat the calibration. If the lateral force range still exceeds 10 µN,


Example of a good calibration. Lateral force is within a 8 µN range.

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Setting up a Scratch Load Function and Performing a Scratch

1. To perform a scratch, you will need to define your samples and approach the surface

for imaging first. These processes are outlined in the “Defining samples” and

“Imaging” sections.

2. Once you have approached the surface, perform a scan to make sure that the surface is

smooth and without craters or artifacts.

CAUTION: This step is important because the lateral force transducer is very fragile.

Any large obstacles in the scratch path may momentarily cause a spike in the lateral

force leading to damage!

3. It is now time to create a scratch load function that will be used in the test. Switch to

the “Load Function” tab in the software and find the “Scratch” sub tab if it does not

direct you there automatically.

4. There is no adopted standard for nano-scratch testing therefore you will need to build

your own function for your specific application. There are a few types of general

functions that will be primarily used. They are constant force scratches and ramped

force scratches. Each type can be in the positive (bottom to top) or negative (top to

bottom) directions. The directionality becomes important if you are using a tip that is

not axis-symmetric such as the Berkovich or cube corner. By going to the “File” menu

and selecting “Open load function,” you will see that there are a few of these types of

functions already saved. It is highly suggested that you modify one of these general

functions and then save it with a customized name instead of trying to build a function

from nothing.

5. For example, let us build a load function for an 8 µm long ramped force scratch in the

negative direction with a load range from 0 to 500 µN. First, go to the “File” menu and

select “open load function.” Load the “ramp_force_scratch_neg_dir” file since it most

closely resembles what we will be doing. The function loaded describes a 45s 10µm

open loop ramped force scratch from 0 to 1000 µN. We will need to make a few

adjustments. First, adjust the “Control Feedback” type to “Load Control” to enable

force feedback. This option is always recommended unless exact scratch depths are

required (displacement control will be used in that case). Next, change the “Max

Displacement” and “Min Displacement” to +4 and -4 µm respectively since we want

an 8 µm long scratch. Finally, adjust the “Peak Force” to 500 µN. The default scratch

time of 45s can be adjusted by clicking on each segment on the graph itself (they will

highly red when correctly selected) and adjusting the “Segment Time” accordingly.

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Scratch load function setup

6. The example above covers just one of the many scratches that the machine is capable

of. The main ideas behind setting up other functions are the same. The most important

parameters are the control feedback selection, the maximum and minimum

displacements, and the peak force.

CAUTION: When selecting the values above, the following considerations must be

made:

The maximum scratch length is 12 µm, but it is recommended that you stay within

10 µm for the best results (-5 to 5 µm in the max and min displacement boxes).

The lateral force transducer will be damaged if the lateral force exceeds 2000 µN.

Also, scratching with large force can easily damage the indenter tip. The lateral

force generated by your scratches will depend on the specific sample properties,

but as a general rule, keep the “Peak Force” under 1000 µN. Contact the system

administrator for permission if you need to go higher.

7. With an appropriate scratch load function configured, it is now time to perform the

scratch. Switch back to the “Imaging” tab and click on the “Test” button on the image

toolbar. It is the same button used to conduct a single indentation test, but since the

software has been switched to “Scratch” mode, a scratch is performed.

Image toolbar – Test button

8. A popup box will ask if the load function is setup correctly, click “Start.” The test will

now begin.

9. After the test is finished, a popup box will ask where to save the scratch data. Select an

appropriate location and file name. The software should switch to the “Analysis” tab

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and show the scratch results afterwards.

10. It is highly recommended that you scan and save an image of the scratched area. These

images are the only way to analyze the final scratch depth and are very important in

wear characterization. The saved topographical images can be analyzed in the

“Triboview” software.

11. The analysis tab does offer a few valuable tools. One such tool is the ability to account

for the gradient or tilt of the sample. In bottom right graph of Lateral Displacement vs

Time, click and drag the two red lines so that first region of the plot is bound. See the

figure below. Then click “Tilt Correction”

Scratch Analysis. Region to set red bars to highlighted.

12. Once you have corrected for the tilt, you can find the “friction” from the sample by

clicking on the friction button. Note that the friction value is not truly the coefficient of

friction of the sample, but also includes the “plowing” resistance. Thus, the deeper the

indent, the higher the friction value will be. For the most accurate friction values, use

shallow scratches. The friction plot displays the results for all segments by default

including those where the tip is held in place and/or where no normal force is applied. The

actual scratching segment is the only one of interest (typically segment 3).

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Example friction plot

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Automated Scratching

1. There is no piezo automation for scratches, however scratches can be automated by

using methods.

CAUTION: Due to the inability to scan the surface prior to scratch, it is strongly

recommended that you do not use scratch methods. This ability should only be used

for samples that are polished to optical quality and where you are certain that the

sample is immaculate at all points on the surface!

2. Setting up a scratch method is very similar to creating the indentation methods. Please

read that section first to get a good background on the procedure.

3. First, create a new method and select the method type to be “Scratch.” Set the filename

and directories accordingly.

CAUTION: Remember, each sample should have its own separate method.

Make sure that the method type is “Scratch”

4. Create a new pattern and select positions for your scratches by using the patterns and

positions sub tabs on the right hand side. The pattern generation and position selection

processes can done by following the similar procedure in the indentation methods

section (Pg. 18, steps 8-10). When creating a scratch pattern such as a grid, keep in

mind how long your scratches will be and adjust the separation distance between

points accordingly.

5. Switch back to the main “Setup” tab and associate your desired pattern and positions

group with your method in the “Patterns” and “Positions” subsections. This process is

also exactly the same as the process for indentation methods (Pg. 18, steps 11-12).

Remember, each method can only have one “Pattern” and one “Group” associated with

it. Therefore, if you will be performing different types of scratches, each scratch type

must have its own method.

6. Click on “Load Function” and select the appropriate scratch load function.

7. Decide whether you would like to save images. If so, click on the “Imaging” button

and configure accordingly.

8. If you have multiple scratch types or are scratching on multiple samples, you will need

to set up methods for each scratch type and for each separate sample.

9. Once all scratch methods have been configured, chain them together in the same way

indentation methods are chained together. (Pg. 19, step 16)

10. Click “Start Method” to begin the method.



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Shutdown procedures

1. If you were imaging or performing a piezo automation, disengage the tip from the sample

surface by switching to the “Imaging” tab and selecting the “Withdraw” button on the

imaging toolbar. It will be greyed out if you have already withdrawn from the surface.

Imaging toolbar – Withdraw button

2. If you were performing an automated method, the tip should have withdrawn

automatically, but double check in the “Imaging” tab to make sure that the button is greyed

out.

3. Once withdrawn, switch back to the “Sample Navigation” tab and use the z-axis controls

to lift the tip up to a Z-height of ~1-3 mm.

An acceptable Z-height for sample removal

4. Open the acoustic enclosure and remove any samples that you have inside

CAUTION: Make sure that you do not touch or accidentally bump the transducer or tip

while removing samples.

5. Turn off the fiber optic light if it is on

6. Close out of the software by clicking the “x” in the top right corner. A popup will ask if

you want to quit Triboscan. Click “Yes.”

7. A popup will ask if you want to save the workspace. Click “Don’t save.”

8. The software will take a few minutes to exit as it resets all of the stage positions.

9. When the software is done closing, hit ctrl-alt-del on the keyboard and lock the computer.

10. Go to the log book and write the finishing time of testing, what kinds of samples you

tested, what kinds of tests were done, and if anything out of the ordinary occurred. It is

very important to record any slight problems that happened and what adjustments you

might have made to solve the problem (things such as raising the setpoint to help your

scan). These changes are sometimes saved in the software and the next user needs to be

aware of such changes.

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Trouble shooting

1. If the tip detects excessive force because it has contacted something, manually swirl the

indenter (top of the pole) z-axis knob clockwise and lift the tip to at least 1 mm above the

point of contact. Reactivate the z-axis motor and start over.

2. If lose contact during imaging, stop it and click disengage button. After it finishes, click

engage button and try again. You can also try re-zeroing the controller by going to the

“Engage” menu from the “Imaging” tab and selecting “Re-Zero the Controller.” If trouble

persists, consider using a slower scanning speed and a higher set point.

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