Method for making a variable length LDD spacer structure

Details Method for making a variable length LDD spacer structure Method for making a variable length LDD spacer structure

1995-06-30

1997-08-05

Bowers, Jr., Charles L.

Semiconductor device manufacturing: process

Making field effect device having pair of active regions...

Having insulated gate

438304, H01L 218238

Patent

active

056542127

ABSTRACT:
A method for making a variable length LDD spacer structure is disclosed. A first insulation layer (i.e., gate oxide) is formed on a semiconductor device having a P-well and an N-well provided in a substrate. A first and a second polysilicon gate are formed on the P-well and the N-well respectively wherein the first insulation layer is interposed between the wells and the gates. A second insulation layer is formed over the first and second gates. N-type impurity ions are selectively implanted to form lightly doped N-type diffusion regions in the P-well. Similarly, P-type impurity ions are selectively implanted to form lightly doped P-type diffusion regions in the N-well. A polysilicon spacer is formed on both side walls of each of the gates. Each spacer covers a portion of the lightly doped N-type and P-type diffusion regions. N-type impurity ions are selectively implanted in a portion of the lightly doped N-type diffusion regions not covered by the spacers. This forms N-type source and drain regions in the P-well adjacent to the lightly doped N-type diffusion regions which have a final length equaling the length of the spacers. Next, the spacers are oxidized or nitridized which enlarges the spacers. P-type impurity ions are selectively implanted in a portion of the lightly doped P-type diffusion regions not covered by the enlarged spacers. This forms P-type source and drain regions in the N-well adjacent to the lightly doped P-type diffusion regions which have a final length equaling the length of the enlarged spacers.

REFERENCES:
patent: 4574467 (1986-03-01), Halfacre et al.
patent: 4925807 (1990-05-01), Yoshikawa
patent: 5134085 (1992-07-01), Gilgen et al.
patent: 5254866 (1993-10-01), Ogoh
patent: 5270233 (1993-12-01), Hamatake
patent: 5278441 (1994-01-01), Kang et al.
patent: 5358879 (1994-10-01), Brady et al.

Affiliated with

Also associated with

Rating

Method for making a variable length LDD spacer structure does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for making a variable length LDD spacer structure, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for making a variable length LDD spacer structure will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1074437