PROCESS OF MANUFACTURE OF TRANSISTOR STRUCTURES Russian patent published in 1994 - IPC

FIELD: microelectronics. SUBSTANCE: after formation of low-doped base region windows for contact base region are opened simultaneously with emitter window. Given region is formed simultaneously with high-doped base region to depth of deposition of low- doped base region. After this window for contact base region is coated with masking layer. Emitter region is formed to depth not less than depth of deposition of contact base region, to value not exceeding diffusion length of incidental charge carriers injected from emitter into base region. This value provides for exit of contact base region into high-doped base region and should not be mutually overlapped with emitter region. In this case concentration of dope in contact base region at boundary with emitter region should be less than in high-doped base region. EFFECT: increased critical collector current. 4 dwg