Method of forming a semiconductor structure with uniform thresho

Details Method of forming a semiconductor structure with uniform thresho Method of forming a semiconductor structure with uniform thresho

1997-09-15

2000-04-18

Nguyen, Tuan H.

Semiconductor device manufacturing: process

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

Having insulated gate

438268, 257330, H01L 21336

Patent

active

06051468&

ABSTRACT:
A MOSFET (Metal Oxide Semiconductor Field Effect Transistors) structure is fabricated by first forming a plurality of trenches in a semiconductor substrate which includes a major surface. The trenches are then lined with insulating material and thereafter filled with conductive material. The process of filling the conductive material in the trenches normally involves an over-etching step for preventing any residual material remaining on the major surface. The over-etching of the conductive material in the trenches alters the evenness of the major surface and presents a problem for the later angular ion implantation of the source layer. As a consequence, the source layer formed includes asymmetrical source segments which generates nonuniform threshold voltage and punch-through tolerance in the MOSFET structure. The inventive method provides a spacer layer to compensate for the unevenness of the major surface. Prior to the ion implantation of the source layer, the spacer layer is formed above the conductive material and surrounding the insulating material adjacent the major surface. Source segments thus formed are symmetrical in shape enabling the fabricated MOSFET structure to operate with uniform punch-through tolerance, uniform threshold voltage, and uniform current distribution during normal operation.

REFERENCES:
patent: 5342798 (1994-08-01), Huang
patent: 5514604 (1996-05-01), Brown
patent: 5672524 (1997-09-01), Liu et al.
patent: 5705409 (1998-01-01), Witek
patent: 5904541 (1999-05-01), Rho et al.
patent: 5907776 (1999-05-01), Hshieh et al.
Stanley Wolf Ph.D. and Richard N. Tauber Ph.D. in Silicon Processing for the VLSI Era, vol. 1: Process Technology, Lattice Press, 1986.

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