GENERAL ELECTRIC CO SYRACUSE NY SPECIAL INFORMATION PRODUCTS DEPT
The output voltage of Cu2TECdTe heterojunction cells might be improved by using instead a pn homojunction, a metalsemiconductor barrier, or some other type of heterojunction. During the present quarter phosphorus diffusion has been used to form shallow pn homojunctions. Some photoresponse was noted, but severe current limiting was experienced due to high p-region sheet resistivity. Also re-examined was goldCdTe barriers, formed by both evaporation and electroless deposition. One evaporated gold cell yielded unusually high open-circuit voltage 680 mv, but current and efficiency were relatively low. Work on short-circuit current improvement chiefly involved improving the area utilization factor from about 89 to 95, using better evaporation masks and hold-down techniques. An attempt was made to gain extrinsic absorption of light by growing CdSexTe1-x mixed crystal films, but no increase in current was noted. Two methods for calculating short-circuit currents and efficiencies from spectral response data are given. A non-linear relationship between output current and illumination intensity in thin film cells was noted and a method for taking this into account in efficiency calculations is given.
Quarterly technical progress rept. no. 6, 1 Jun-31 Aug 68,