BORON DELTA-DOPING IN SI AND SIGE AND ITS APPLICATION TOWARD FIELD-EFFECT TRANSISTOR DEVICES

The mobility behavior of boron delta (delta)-doped Si, Si1-xGex(0 less -than-or-equal-to x less-than-or-equal-to 1) is investigated, which in cludes the first mobility measurements reported for B delta-doped Si1- xGex and Ge. The expected mobility enhancement from delta doping is no t realized in Si:B due to the heavy effective mass of holes. However, some enhancement may be possible at lower doping levels for narrower w ells. Indications of mobility enhancement have been realized for delta -doped Ge:B because of the relatively light effective mass. We also pr esent the implementation of boron delta-doped layers in the fabricatio n of (i) the first SiGe:B delta-FET and (ii) the first coupled delta-l ayer Si:B delta-FET.