Process for manufacture of low voltage power MOSFET device

Details Process for manufacture of low voltage power MOSFET device Process for manufacture of low voltage power MOSFET device

2005-02-01

2005-02-01

Fourson, George (Department: 2823)

Semiconductor device manufacturing: process

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

Having insulated gate

Reexamination Certificate

active

06849507

ABSTRACT:
A trench type power MOSFET has a thin vertical gate oxide along its side walls and a thickened oxide with a rounded bottom at the bottom of the trench to provide a low RDSONand increased VDSMAXand VGSMAXand a reduced Miller capacitance. The walls of the trench are first lined with nitride to permit the growth of the thick bottom oxide to, for example 1000 Å to 1400 Å and the nitride is subsequently removed and a thin oxide, for example 320 Å is regrown on the side walls. In another embodiment, the trench bottom in amorphized and the trench walls are left as single crystal silicon so that oxide can be grown much faster and thicker on the trench bottom than on the trench walls during an oxide growth step. A reduced channel length of about 0.7 microns is used. The source diffusion is made deeper than the implant damage depth so that the full 0.7 micron channel is along undamaged silicon. A very lightly doped diffusion of 1000 Å to 2000 Å in depth could also be formed around the bottom of the trench and is depleted at all times by the inherent junction voltage to further reduce Miller capacitance and switching loss.

REFERENCES:
patent: 4992390 (1991-02-01), Chang
patent: 4992838 (1991-02-01), Mori
patent: 6020600 (2000-02-01), Miyajima et al.
patent: 6028337 (2000-02-01), Letavic et al.
patent: 6228720 (2001-05-01), Kitabatake et al.
patent: 6262453 (2001-07-01), Hshieh
patent: 6368940 (2002-04-01), Amon et al.
patent: 6534365 (2003-03-01), Kim et al.
patent: 6580123 (2003-06-01), Thapar
patent: 409283535 (1997-10-01), None
patent: 2000-058635 (2000-02-01), None
patent: 2002037420 (2002-05-01), None

Affiliated with

Also associated with

Rating

Process for manufacture of low voltage power MOSFET device does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for manufacture of low voltage power MOSFET device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for manufacture of low voltage power MOSFET device will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3477261