A planar NPN InSb transistor fabricated using proton bombardment techniques

Non p diodes anti an n-channel depletion mode IGFET have been made on InSb using a proton bombardment technique. Extending the technique one step further has made it possible to fabricate a lateral npn transistor on8-9 \times 10^{13}cm^-3germanium doped InSb. Small signal betas of2\frac{1}{2}have been obtained at collector currents of approximately 200 microamperes and a collector emitter voltage of about 0.2 volt. The base region is optically active. By increasing the base drive, the optical response can be increased by about a factor of three over the open base case before noise becomes significant.