公开(公告)号：JPH10214965A

公开(公告)日：1998-08-11

申请号：JP855498

申请日：1998-01-20

Applicant: IBM

Inventor： GAMBINO JEFFREY P ,  GARRY BELLA BRONNER ,  MANDELMAN JACK ALLAN ,  NESBIT LARRY A

IPC: H01L29/78 ,  H01L21/762 ,  H01L21/8234

Abstract: PROBLEM TO BE SOLVED: To adjust the threshold voltage at the corner of a device without requiring any additional mask by doping the central part of a channel region at some concentration and doping a channel region adjacent to a corner region at a higher concentration. SOLUTION: N type (arsenic) dopant ions 19 are implanted compensatingly. The compensatory implantation is performed in order to compensate for the threshold voltage implantation at the part of the side wall of STI trench structures 18a-18c contiguous to the corner of a substrate 12 other than the corner region 25 and to suppress the effect of P-type ion implantation 21 in the channel region onto the following stage by means of N type doping ions 19 so that the corner region 25 has a higher doping concentration after boron B doping stage. A spacer 16 prevents the compensatory implantation at the corner of the device except the central channel regions 20a, 20b, 20c and 20d.