GB1010476A - Improved photo-electric generators - Google Patents

Abstract

1,010,476. Photo-electric devices. MINISTER OF AVIATION. March 4, 1963 [June 15, 1962], No. 1379/62. Heading H1K. A photo-electric generator comprises, Figs. 1 and 2, a plurality of regions 1, 2 and 3, ofsemi-conducting material, one part 6, of each region being of one (P) conductivity type, and another part 4, of each region being of the opposite (N) conductivity type, the two parts together forming a PN junction in each region for receiving radiation L, incident upon the generator, and electrical connections 8, between the regions, connecting the PN junctions in series, the regions being physically joined to each other to produce a solid integral structure, by semi-conductor material 5 of the one (P) conductivity type joined to the parts of the regions of opposite conductivity type. The layer 4 is grown epitaxially on the substrate layer 5 and the layers 6 are diffused into discrete parts of layer 4 by oxide masking and photo litho graphic techniques. Slots 7 are cut through layer 4 to isolate the regions 1, 2 and 3 from one another. The connecting wires 8 and 9 are thermo-compression bonded into the respective parts of the regions. In another embodiment, Fig. 3 (not shown), the slots 7 are replaced by regions of the one (P) conductivity type, deep diffused by masking means into the layer 4. A silicon dioxide layer 14, Fig. 4, may cover the assembly leaving gaps for the radiation to reach the surface 6A of layer 6. The connections 8 of Fig. 1, may be replaced by evaporated metal layers 16 making contact with the respective parts of the regions through holes in the silicon dioxide layer. In another embodiment, Fig. 5, layers 17, corresponding to layer 4 of Fig. 1 are deep diffused into the substrate layer 5. In a modification, Fig. 6 (not shown), of the embodiment of Fig. 3, the substrate layer 5 may be dispensed with. Suitable semi-conductor materials are Si, Ge, In Sb, Ga As, Cd S, and Cd Hg Te.