belle-ii meeting nov 09 19. nov. 2009 thomas bergauer (hephy vienna) status of dssd sensors

Belle-II Meeting Nov 09 19. Nov. 2009

Thomas Bergauer (HEPHY Vienna)

Status of DSSD Sensors

Overview

• Prototype DSSDs have been ordered at – Hamamatsu (rectangular shape)

– Micron Semiconductor (wedge shape)

• I will present status of both orders

2Thomas Bergauer (HEPHY Vienna)19. Nov. 2009


SVD Layout

Rect (122.8 x 38.4 mm , 160 / 50 um pitch)2

Rect (122.8 x 57.6 mm , 240 / 75 um pitch)2

W e dge (122.8 x 57 .6-3 8.4 m m , 240 / 75..50 um p itch)2

0

0

10

3

45

6[cm] layers

[cm]

20

-10-20-30 10 20 30 40

6

z APVs

z APVs

z APVs

64

4

4 4

46

6

6

rphi APVs

rphi APVs

rphi APVs

6

64

4

4 4

4

4

46

666 6

6 6 6

6

Layer # Ladders

Rect. Sensors[50μm]

Rect. Sensors[75μm]

Wedge Sensors

APVs

6 17 0 68 17 850

5 14 0 42 14 560

4 10 0 20 10 300

3 8 16 0 0 192

Sum: 49 16 130 41 1902

RECTANGULAR SENSORSHamamatsu Order


Hamamatsu Status

• HPK decided to re-start DSSD production– Not only for Belle. They have been pushed also

from other interested (Japanese) parties

• KEK was in contact with Japanese sales representative and engineer

• Beginning of Oct. 2009: Mask Production– Unfortunately without the possibility to add test

structures

• Delivery: March 2010 (<=30pcs.)


Rectangular DSSD Layout


• Overall Size:– 124.88 x 59.6 mm

• P-side– 768 long readout strips– 75 micron readout pitch– 37.5 micron strip pitch

(one intermediate strip)– Second row of bonding pads

compatible to Origami bonding scheme

• N-side– 512 short readout strips– 240 micron readout pitch– 120 micron strip pitch

(one intermediate strip)

Rectangular DSSD Specifications


WEDGE SENSORSMicron Order



Micron Semiconductor Ltd.

• Company in Sussex, England, founded 1983• Contact persons:

– Colin Wilburn (Director)– Susan Walsh (Designer)

• Financial:Item Quantity Unit Price Sub Total

Masks 16 2,200 35,200

Probe card 1 1,800 1,800

DSSDs 10 2,000 20,000

Shipping boxes 10 200 2,000

Shipments 5 200 1,000

Sum € 60,000 (eq. 8M¥)


Wedge DSSD specifications

• Resistivity: 8 kΩcm (n-type); crystal orientation <100>• Thickness: 300 +/- 10 microns• Full Depletion (FD): 40 volts typical; 70 volts maximum• Operating Voltage: FD to 2x FD• Minimum Breakdown Voltage (10uA): 2.5x FD• Total drain leakage current (20 degrees C): 2uA typical; 10uA

maximum (at 50% rH)

• Polysilicon resistor 15 +/- 5 megohms• Coupling capacitor > 1.2 pF / cm strip length and per microstrip

width (100pF typical)• Interstrip resistance 100MΩ min, 1 GΩ ohm typical (P-Side);

10 MΩ min, 100MΩ typical (N-side)

11Thomas Bergauer (HEPHY Vienna)

Micron Wafer Layout (to be confirmed)

Teststructuresfor p-side

Teststructuresfor n-side(no GCD)

Baby sensor 1p-side: 512 strips 50 µm pitch 1 interm. stripn-side: 512 strips 100 µm pitch 1 interm. strip atoll p-stop

3 different GCDsfor the n-side

Main sensorp-side: 768 strips 75-50 µm pitch 1 interm. stripn-side: 512 strips 240 µm pitch 1 interm. strip combined p-stop

Quadratic baby sensors 2,3,4p-side: 512 strips 50 µm pitch 1 interm. stripn-side: 256 strips 100 µm pitch 0 interm. strip different p-stop patterns

1) atoll p-stopvarying distance from strip

2) conventional p-stopvarying width

3) combined p-stopvarying distance from strip

19. Nov. 2009

Open Points: Guard Ring Design

• We proposed single guard ring with outer n-ring (n_sub) similar to HPK design– 800 micron size

• Micron wants to implement their own multi-guard ring design– Three guard rings– 1000 micron size– Requires NDA signed by us– They do not like n_sub implant;

however, this make IV tests more complicated


combined

Open Points: p-stop layout


p-stops connected

p-stops isolated

14Thomas Bergauer (HEPHY Vienna)

Micron Wafer Layout (to be confirmed)

Teststructuresfor p-side

Teststructuresfor n-side(no GCD)

Baby sensor 1p-side: 512 strips 50 µm pitch 1 interm. stripn-side: 512 strips 100 µm pitch 1 interm. strip atoll p-stop

3 different GCDsfor the n-side

Main sensorp-side: 768 strips 75-50 µm pitch 1 interm. stripn-side: 512 strips 240 µm pitch 1 interm. strip combined p-stop

Quadratic baby sensors 2,3,4p-side: 512 strips 50 µm pitch 1 interm. stripn-side: 256 strips 100 µm pitch 0 interm. strip different p-stop patterns

1) atoll p-stopvarying distance from strip

2) conventional p-stopvarying width

3) combined p-stopvarying distance from strip

1)

2)

3)

19. Nov. 2009


Micron Wedge DSSD - Summary[µm] number pitch Implant

widthAL width AC pad DC Pad Remarks

P strip(readout)

768 75 – 50

14 20 50 x 200

42 x 108

AC pads: 2 rows, staggered

DC pads: 1 row, staggered

N strip(readout)

512 240 30 40 260 x 60

180 x 60

AC pads: 2 rows, not staggered

DC pads: 1 row, not staggered

Bias ring 1 75 95 symmetric

MGR 3 tbd. tbd.

Edge ring

1 tbd. tbd. dicing edge

• One intermediate strip on both p-side and n-side

• Outer dimensions:– Width on top: 60.15 ± 0.05 mm– Width on bottom: 40.60 ± 0.05 mm– Length: 125.11 ± 0.05 mm

• Note: all dimension values are preliminary, i.e. they are subject to discussion and are awaiting final confirmation by Micron!

Schedule


• Most urgent: agree on open points with Micron to start production as fast as possible

• Wait for delivery– Hamamatsu: end of March 2010– Micron: Summer 2010

Future next steps with prototype DSSDs

• Electrical Characterization in Vienna

• Build Origami module with HPK sensors

• Build full ladder comprising – several Origami modules

– slanted module with Micron sensor

• Testbeam in autumn 2010 at CERN

• Irradiation tests of sensors– Together with electronics?

– Where? When?


THE END.



P-Side, AC and DC pads

AC pads: 50 x 200 µm,2 staggered rows

Marker with 10 µmdiameter (easily

adjustable) on every128th AC pad

• As long as the pad pitch within each row is constant, different pitches in different pad rows do not cause problems for bonding.

DC pads: 42 x 108 µm1 staggered row


N-Side, P-Stop pattern (implants only)

• According to Y. Iwata et al., this “combined pattern” performs best for a tradeoff between charge collection efficiency and interstrip capacitance.

Individual P-Stop atoll

N+ implantof strip

Additional P-Stop „strip“ splitting theaccumulation layer


N-Side, AC and DC pads

• AC pad size: 260 x 60 µm, marker on every 128th pad, 2 rows, no staggering• DC pad size: 180 x 60 µm, 1 row, no staggering

belle-ii meeting nov 09 19. nov. 2009 thomas bergauer (hephy vienna) status of dssd sensors

Documents

strip n

strip atoll p

combined p

different p

conventional p

typical n

outer nring n

main sensor p