A trench gate charge storage type igbt device with clamping structure and its manufacturing method

A charge storage and trench gate technology, which is applied in semiconductor/solid-state device manufacturing, electric solid-state devices, electrical components, etc., can solve the problems affecting the compromise characteristics of device switching loss, increasing device switching loss, and reducing switching speed, etc.

Active Publication Date: 2020-03-17
UNIV OF ELECTRONICS SCI & TECH OF CHINA
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The implementation of method (1) will increase the gate-emitter capacitance and gate-collector capacitance at the same time, and the switching process of the IGBT is essentially the process of charging / discharging the gate capacitance, so the increase in the gate capacitance will Makes the charging / discharging time longer, which in turn causes the switching speed to decrease
Therefore, the deep trench gate depth will reduce the switching speed of the device, increase the switching loss of the device, and affect the compromise characteristics of the device's conduction voltage drop and switching loss; and the implementation of method (2) will increase the device's switching loss The gate capacitance will reduce the switching speed of the device and increase the switching loss, which will affect the compromise between the conduction voltage drop and switching loss of the device. On the other hand, it will also increase the saturation current density of the device and make the short-circuit safe working area of ​​the device worse.
In addition, the gate oxide layer in the trench gate structure is formed in the trench by one thermal oxidation. In order to ensure a certain threshold voltage, the thickness of the entire gate oxide layer is required to be small. However, the MOS capacitance and the thickness of the oxide layer Inversely proportional, which makes the thin gate oxide thickness in traditional CSTBT devices will significantly increase the gate capacitance of the device, and the electric field concentration effect at the bottom of the trench will reduce the breakdown voltage of the device, resulting in poor reliability of the device

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
  • A trench gate charge storage type igbt device with clamping structure and its manufacturing method
  • A trench gate charge storage type igbt device with clamping structure and its manufacturing method
  • A trench gate charge storage type igbt device with clamping structure and its manufacturing method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0078] This example proposes as figure 2 A trench gate charge storage type IGBT device with a clamping structure is shown, including: a collector structure, a drift region structure, an emitter structure and a trench gate structure; the collector structure includes a P+ collector region 12 and is located at The collector metal 13 on the lower surface of the P+ collector region 12; the drift region structure includes an N-type electric field stop layer 11 and an N-type drift region layer 10 located on the upper surface of the N-type electric field stop layer 11, and the N-type electric field stop layer 11 is located on the upper surface of the P+ collector region 12; the emitter structure includes an emitter metal 1, a P+ contact region 2, an N+ emitter region 3, a P-type base region 8 and an N-type charge storage layer 9, and the emitter structure Located on the top layer of the N-type drift region layer 10, the N-type charge storage layer 9 is located between the P-type base...

Embodiment 2

[0084] This example proposes as image 3 The trench gate charge storage type IGBT device with a clamping structure shown is the same as the embodiment 1 except that the clamping electrode dielectric layer 15 is thicker than the gate dielectric layer 7 .

[0085] Compared with Embodiment 1, this embodiment can further reduce the gate capacitance on the one hand, increase the switching speed of the device and reduce the switching loss, and on the other hand can further improve the electric field concentration effect at the bottom of the trench and increase the breakdown voltage of the device. , improve device reliability.

Embodiment 3

[0087] This example proposes as Figure 4 A trench gate charge storage type IGBT device with a clamping structure is shown, except that the shape of the clamping electrode 14 is different from that of the embodiment 1, and the rest of the structure is the same as that of the embodiment 1; in this embodiment, the clamping electrode 14 It is composed of connected first clamping electrode and second clamping electrode, the width of the first clamping electrode is larger than the width of the second clamping electrode, so that the two are connected with the N-type charge storage layer 9 and the N-type drift region 10 The thickness of the clamping electrode dielectric layer 15 is different. As can be seen from the figure, the clamping electrode dielectric layer 15 is stepped. This embodiment can further reduce the gate capacitance on the basis of Embodiment 1, thereby improving the device The switching characteristics, and can further improve the electric field concentration effect...

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

A trench gate charge storage type IGBT device with a clamping structure and a manufacturing method thereof belong to the field of semiconductor power devices. In the present invention, a clamping electrode connected with the emitter metal through a series diode structure is introduced under the gate electrode in the device trench, and a P-type layer connected thereto is arranged under the clamping electrode. The invention can effectively shield the adverse effect of the increase of the doping concentration of the N-type charge storage layer on the withstand voltage performance of the device, overcome the contradiction between the forward conduction and the withstand voltage of the traditional CSTBT structure; reduce the saturation current density of the device, and improve the short circuit of the device Safe working area; increase the switching speed of the device and reduce the switching loss of the device; at the same time, no negative differential capacitance effect will be formed during the dynamic process of turning on, which can effectively avoid current, voltage oscillation and EMI problems during the dynamic process of turning on, and improve the device’s performance. Reliability; improve the electric field concentration effect at the bottom of the trench, and increase the breakdown voltage of the device.

Description

technical field [0001] The invention belongs to the technical field of semiconductor power devices, in particular to an insulated gate bipolar transistor (IGBT), in particular to a trench gate charge storage type insulated gate bipolar transistor (CSTBT) with a clamping structure and its manufacture method. Background technique [0002] Insulated gate bipolar transistor (IGBT), as one of the core electronic components in modern power electronic circuits, is widely used in various fields such as transportation, communication, household appliances, and aerospace. Insulated gate bipolar transistor (IGBT) is a new type of power electronic device composed of an insulated field effect transistor (MOSFET) and a bipolar junction transistor (BJT), which can be equivalent to a MOSFET driven by a bipolar junction transistor. . IGBT combines the working mechanism of MOSFET structure and bipolar junction transistor. It not only has the advantages of MOSFET easy to drive, low input impe...

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): H01L29/06H01L29/423H01L29/739H01L27/02H01L21/331H01L21/28
CPCH01L27/0255H01L27/0296H01L29/0623H01L29/0684H01L29/42312H01L29/66348H01L29/7397H01L29/7398
Inventor 张金平赵倩刘竞秀李泽宏任敏张波
Owner UNIV OF ELECTRONICS SCI & TECH OF CHINA
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap