Radiation Generators including Semiconductive Bodies

摘要

1,174,597. Luminescent materials. WESTERN ELECTRIC CO. Inc. 20 Dec., 1966 [20 Dec., 1965], No. 56881/66. Heading C4S. [Also in Division H1] An electro-luminescent semi-conductor device comprises a single AIII-BV semi-conductor body containing a group IV element as substantially the sole significant impurity, a portion of the body being compensated by the Group IV element acting as both donor and acceptor. Fig. 2 shows a gallium arsenide crystal 31 with PN junction 35 from which light 42 is emitted on application of forward bias. The crystal is prepared by heating a silicon doped GaAs crystal in hydrogen to out diffuse arsenic from the upper portion and zinc is then diffused in to form P + region 36 to provide a low-resistance contact. The out diffusion of the arsenic provides a compensated portion 34 in which the silicon atoms act as both donor and acceptor. The compensated portion may alternatively be provided by freezing out from a gallium rich silicon doped GaAs melt and then heat treating in an over-pressure of arsenic. In another embodiment (Fig. 1, hot shown), light is directed against a weak N or compensated region (14), resulting in photo-luminescence and emission of light (19); the crystal again consists of silicon doped (5 x 1018 atoms/c.c.) gallium arsenide, the compensating region being produced as before, by outdiffusioning arsenic from the region unprotected by silicon oxide layers (13). Gallium phosphide may be used in place of gallium arsenide and germanium or tin in place of silicon. The construction may be adapted to provide coherent light, and cathodoluminescence may also be utilized.