Unlock instant, AI-driven research and patent intelligence for your innovation.

Power trench MOSFET having SiGe/Si channel structure

A trench and channel region technology, applied in the direction of final product manufacturing, sustainable manufacturing/processing, climate sustainability, etc., can solve problems such as limiting device performance, limiting efficacy, cost, etc., to reduce parasitic gate resistance , the effect of improving device characteristics

Inactive Publication Date: 2013-03-27
FAIRCHILD SEMICON CORP
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

While suicide can be used to reduce this series resistance, the effectiveness of the process is limited by the physical structure of these transistors
Channel resistance, or Ron also limits device performance and thus converter efficiency
Larger units can reduce Ron, but larger units are more expensive

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Power trench MOSFET having SiGe/Si channel structure
  • Power trench MOSFET having SiGe/Si channel structure
  • Power trench MOSFET having SiGe/Si channel structure

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0039] figure 1 It is a cross-sectional view of an n-channel trench gate power MOSFET improved by combining the embodiment of the present invention. The device includes an n-type source region 110 , a body formed by a p-well 120 , an n-type drain region 130 , a substrate 160 , a gate 140 , and a metal contact 150 .

[0040] Parasitic npn bipolar transistors are inherent in this structure. Specifically, the emitter of the parasitic device is the source region 110 , the base thereof is the body or well region 120 , while the collector of the parasitic device corresponds to the epi region 130 . If this parasitic transistor is biased into its active-forward mode of operation, destructive failure will occur. This occurs, for example, during avalanche breakdown caused by an unclamped inductive switching (UIS) event. Holes generated by impact ionization may flow through the base formed by the P-well 120, causing an ohmic voltage drop. If this voltage drop exceeds about 0.6V, the ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

Devices, methods, and processes that improve immunity to transient voltages and reduce parasitic impedances. Immunity to unclamped inductive switching events is improved. For example, a trench-gated power MOSFET device having a SiGe source is provided, where the SiGe source reduces parasitic npn transistor gain by reducing hole current in the body or well region, thereby decreasing the likelihood of a latch-up condition. A trench-gated power MOSFET device having a SiGe body or well region is also provided. A SiGe body reduces hole current when the body diode is turned on, thereby reducing reverse recovery power losses. Other device characteristics are also improved. For example, parasitic gate impedance can reduced through the use of a poly SiGe gate. Also, channel resistance can be reduced through the use of a SiGe layer near the device's gate and a thick oxide region can be formed under the trench gate to reduce gate-to-drain capacitance.

Description

[0001] This application is a continuation-in-part of U.S. Patent Application No. 11 / 245995, filed October 7, 2005 and claims U.S. Provisional Application Nos. 60 / 617167, 60 / 617464, Priority Nos. 60 / 617463, and 60 / 617168, the entire contents of which are hereby incorporated by reference. technical field [0002] The present invention relates generally to power transistors, and more particularly to metal oxide semiconductor gate (MOS gate) power transistors having silicon germanium (SiGe) sources, wells, channels, polysilicon germanium gates, or combinations thereof. Background technique [0003] Trench gate power MOSFET devices are a popular choice for many demanding applications such as DC-DC converters. These applications can be very demanding, putting a lot of strain on these transistors. For example, sinking and sinking large currents into inductive loads can result in large voltage transients at the terminals of one or more devices. In particular, large voltage excursi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H01L29/80H10B12/00
CPCH01L29/66734H01L29/7813H01L29/7782H01L29/4933H01L29/1054H01L29/165H01L29/49Y02P70/50H01L29/80
Inventor 朴赞毫王琦
Owner FAIRCHILD SEMICON CORP