IGBT Reverse Recovery Speed via Ion Implantation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The reverse recovery speed of reverse diodes in Insulated Gate Bipolar Transistors (IGBTs) is slow, leading to poor performance.

Innovation Solution

A fabrication method for IGBTs that involves implanting hydrogen, arsenic, or nitrogen ions into the substrate to form an n-type heavily doped layer, followed by annealing to create a recombination center, accelerating the reverse recovery speed of the built-in reverse diode.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If phosphorus ion implantation is used to form the n+ junction of the reverse diode, then the reverse diode can be formed, but the reverse recovery speed is slow

Engineering Contradiction:

Improvereverse recovery speedVSAvoidperformance of IGBT

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The patent changes the ion implantation parameters by switching from phosphorus ions to hydrogen ions, and adjusts the annealing temperature (200-400°C) and time (1-5 hours) to create recombination centers that accelerate reverse recovery speed while maintaining IGBT performance

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces an intermediary mechanism by using hydrogen ion implantation followed by annealing to create recombination centers in the n-type heavily doped layer, which act as mediators to speed up the reverse recovery process of the reverse diode

Inventive Principle:

Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This method shortens the reverse recovery time and improves the performance of the IGBT by replacing traditional phosphorus ion implantation with hydrogen or arsenic/nitrogen ion implantation and activation through annealing.

Implementation Method 1

Implanting hydrogen ions, or arsenic ions, or nitrogen ions into a substrate from a back surface of the substrate

Methodology Applied

Scientific EffectIon implantation: Ion Implantation

Implementation Method 2

Annealing the n-type heavily doped layer of the reverse diode, so as to form a recombination center in the n-type heavily doped layer

Methodology Applied

Scientific EffectAnnealing: Annealing

Data Source

PatentUS11605725B2Insulated gate bipolar transistor and fabrication method therefor

Publication Date: 2023.03.14 ADVANCED SEMICON MFG CO LTD

AI summary

An insulated gate bipolar transistor and a fabrication method therefor, wherein the fabrication method for the insulated gate bipolar transistor comprises the following steps: implanting hydrogen ions, arsenic ions, or nitrogen ions into a substrate from a back surface of the insulated gate bipolar transistor so as to form an n-type heavily doped layer (202) of a reverse conduction diode, the reverse conduction diode being a reverse conduction diode built into the insulated gate bipolar transistor. The described fabrication method and the obtained insulated gate bipolar transistor from a recombination center in an n+ junction of the reverse conduction diode, thereby accelerating the reverse recovery speed of the built-in reverse conduction diode, shortening the reverse recovery time thereof, and improving the performance of the insulated gate bipolar transistor.