Patent GB-1037519-A (GB)
Title: Electrical circuits
IPC: H01L27/092
Filed: 1963-05-01
Abstract: 1,037,519. Semi-conductor devices. RADIO CORPORATION OF AMERICA. May 1, 1963 [May 31, 1962], No. 17274/63. Heading H1K. [Also in Divisions G4 and H3] A solid state structure consists of a pair of devices each having a layer of semi-conductor material and three electrodes, two of them connected to the layer and the third which is capacitively coupled with the layer extending over part of the space between the other two, and means connecting each second electrode to the capacitive contact of the other device. Two electrodes 32, 34 (Fig. 3) are provided on a substrate of glass, ceramic or fused quartz by evaporating indium, gold or tin through a mask. Alternatively they may be deposited by a paste of metallic particles painted on regions of the substrate or sputtered thereon. The electrodes are of different lengths and insulating material 36 (Fig. 4) is then applied over the extending portion of electrode 34, the insulant may be of silicon dioxide, aluminium oxide or calcium fluoride as insulator or zinc sulphide as a highgap semi-conductor of high resistivity. A layer of semi-conductor material 40 is then deposited on the top surface of the substrate 30 and that portion of the electrode 34 which is separated from the semi-conductor 40 by the insulating film 36 provides a capacitive connection thereto. The layer 40 may be of silicon, germanium, phosphides, arsenides, and antimonides of aluminium, calcium and indium, or compounds such as sulphides, selenides and tellurides of zinc and cadmium. Zinc oxide may also be used. The device is completed by a second insulating film 42 (Fig. 3) provided on only the lower half of the substrate and a second pair of electrodes 44 and 46 deposited on the top of the structure. A schematic diagram of the completed device is shown in Fig. 26. In a further arrangement (Fig. 6a) the four electrodes are formed on one side of the semi-conductive layer in a similar operating technique as described above. Either of the above types of device may be employed in chain formation to form a shift register in which case drain and source electrodes of one device may be connected to adjacent " flipflops " by thin layer deposition techniques with potential control leads fixed to the electrodes of the devices by silver paste. The manufacture of resistors, capacitors and diodes by evaporation techniques of conductive material on to semi-conductive layers is described, which methods are employed where necessary in the shift register chain of devices to complete the circuit arrangements of the register in integrated form. Another embodiment (Figs. 15a and 17) employs the pair of devices in integrated form with an extra " gate electrode " on each. Again deposition of electrodes of desired length and confirmation is effected on an S-C layer with intermediate provision of insulating coatings. A further embodiment (Figs. 19a and 19b) employs a substrate 252 upon the lower part of which is first deposited a layer of N-type cadmium sulphide 250, then a layer of P-type lead sulphide 254 on the upper part of the substrate. Two strip electrodes 258 and 260 serve as drain and gate electrodes for four thin film devices 262, 264, 266 and 268. Further deposition steps of insulant and conductors produces an integrated circuit of four devices as shown in Fig. 196. Arrangements of such four-device integrated circuits in a shift register are disclosed (Figs. 23 and 24, not shown).