6.6 MICRON AND SUBMICRON PATTERNS FOR SEMICONDUCTOR DE- VICES AND INTEGRATED CIRCUITS, H. J. Schuetze and K. E. Hen- nings, Telefunken AG, Ulm, West Germany.

The fabrication of microwave planar transistors and very high speed integrated circuits is well known to depend on the realization of transislor or circuit patterns in the micron and submicron range. This paper discusses results of basic studies on the generation of such micro-patterns on photo- graphic plates, and photosensitive resists as well as pattern etching in Si02 and metal films.

The resolving power of various lenses on high resolution plates and pho- toresists has been measured as a function of the objective and illumination aperture. A resolution of 3000 lines per millimeter at an aperture close to 1 is obtained, ,demonstrating that the results are only diffraction limited. With a specially designed microscope objective, for example, a useful pattern of 1 micron linewidth, uniform over an image area of 80 x 80 mils, has been produced. For still larger image areas, a new lens has shown a resolving power of 375 lines per millimeter, uniform over an image area of 1 inch diameter. Presently, useful patterns of 3 microns minimum linewidth may be produced uniformly on 1 inch substrates, without using the step and repeat method in the final reduction step. Note: Joint cooperation with Carl Zeiss, Oberkochen, West Germany, is grate- fully acknowledged.

Session 7: Quantum Electronics - Lasers and Detectors Thursday, Oct. 21, 9:00 a.m. to Noon

North Cotillion Room Chairman: S. E. Harris Organizer: M. Nathan 7.1 THE USE OF LASERS IN RAMAN SPECTROSCOPY, S. P. S. Porto,

The advent of the laser as a Raman source has revitalized the interest of physicists in the Raman effect. Measurements of precise depolarization factors, angular dependence, and absolute cross sections for Raman scatter- ing became easier to make. The use of the 6328 A He-Ne and the 4880 and 5145 A argon ion laser lines allow high signal-to-noise continuous recordmg of the Raman effect for liquids and solids. The problem of averaging all the random orientations of 'the liquid molecules has been restudied, and its effect on the angular dependence and depolarization factors of the Raman lines in liquids will be given. Measurements of Raman scattering in solids, where the use of the laser is revolutionizing the subject, will be discussed.

Bell Telephone Laboratories, Murray Hill, N. J.

7.2 AVALANCHE INJECTION LASER IN P-TYPE GaAs, K. Weiser and J. F. Woods, IBM Watson Research Center, Yorktown Helghts, N. Y.

Light emission between liquid helium temperature and room temperature, as well as lasing below 90"K, has been observed from p-type GaAs structures containing high resistivity regions. These regions are obtained at the boundary of the zinc layer when zinc is diffused into (p-type) manganese-doped GaAs. Voltage probes along the current direction, normal to the interface between the zinc and manganese dominated regions, show that the high resistivity region is p-type. The temperature dependence of the resistance of the region shows that it is still dominated by manganese, as is t h e bulk material into which the zinc is diffused. No unequivocal determinatlon of. the wldth of the region could be made, but various indications shqw that it 1s of the order of one micron. In lasing structures zinc is diffused into the opposite faces of a