Amplification of a light signal in metal–insulator–semiconductor–insulator–metal structures

An investigation was made of the amplification of light signals in metal–SiO₂(TiO₂)–Si–SiO₂(TiO₂)–metal structures. A gain of about 32 was achieved. When the source of light (an electroluminescent diode) was operated as a laser, the ratio of the output power of the structure (which produced a photocurrent) to the power consumed in the diode exceeded unity and sometimes amounted to four. It is concluded that metal–insulator–semiconductor–insulator–metal structures can be used as high-sensitivity and fast-response radiation detectors.