ON THE MECHANISM OF APPEARANCE OF SPACE-CHARGE-LIMITED CURRENT IN HIGHER MANGANESE SILICIDE (HMS)-SI[MN]-HMS AND HMS-SI[MN]-M STRUCTURES

Experimental photocurrent-voltage characteristics of higher manganese silicide (HMS)-Si(Mn)-HMS and HMS-Si(Mn)-M structures have been analys ed. The mechanism is considered of current flow under illumination wit h h nu less than or equal to E-g radiation. In the structures under st udy, the space-charge-limited-current (SCLC) mode is realized in the t emperature interval 77-270 K, and photocurrent-voltage characteristics show regions of linear and quadratic dependence and a region of steep current rise. The high photosensitivity of these structures and the o ccurrence of SCLC is explained by (i) formation, in the subsurface reg ion of Si diffusion-doped with manganese, of a contact layer of HSM in jecting holes into silicon; and (ii) the fact that at low temperature the high-resistance base region of the structures illuminated with int rinsic radiation becomes a low-resistance conducting layer, and a tran sition layer in which the SCLC mode is realized is formed at the HMS-S i(Mn) phase boundary.