Electroluminescence at silicon band gap energy from mechanically pressed indium-tin-oxide/Si contact

Room temperature electroluminescence (EL) corresponding to Si band gap ener gy is observed from mechanically pressed indium-tin-oxide (ITO)/Si contact. The intensity of luminescence is pressure dependent and highly related to the current-voltage characteristics. Increasing pressure simultaneously red uces the rectification property and the luminescence. The physical reason f or EL is attributed to the formation of an air gap between the ITO and the Si substrate. The role of the air gap is similar to the oxide layer in the metal-oxide-semiconductor structure. The influence of surface quality of th e Si substrate on the luminescence spectrum is also studied, and found to b e significant. (C) 2001 American Institute of Physics.