Semiconductor Protection Circuit Charge Discharge Paths

Solution Overview

Problem

Conventional semiconductor devices face challenges in protecting metal interconnections and gate electrode oxide layers from plasma-induced damage during fabrication, as existing protection circuits require multiple diodes, increasing circuit area and complicating design due to limited charge discharge capacity.

Innovation Solution

A protection circuit incorporating a charge discharging unit with multiple discharge paths and a buffer unit to manage charge discharge, allowing for increased charge capacity and preventing overcurrent, thereby simplifying fabrication and reducing circuit area.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple diodes are used in the protection circuit to increase charge discharge capacity, then the charge discharge capacity is improved, but the circuit area increases and design complexity increases

Engineering Contradiction:

Improvecharge discharge capacityVSAvoidcircuit area

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The invention merges the protection function with the existing transistor structure by using the source and drain of the transistor as charge discharge paths. This combines multiple functions (switching and charge discharge) into a single structure, eliminating the need for separate protection diodes and reducing circuit area while maintaining charge discharge capacity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The transistor structure is designed to serve multiple functions: it acts as both a switching element and a charge discharge path. The source and drain regions are configured to discharge plasma-induced charges, making the transistor universal in its functionality and eliminating the need for dedicated protection components.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If multiple diodes are used in the protection circuit to increase charge discharge capacity, then the charge discharge capacity is improved, but the device complexity increases

Engineering Contradiction:

Improvecharge discharge capacityVSAvoidcircuit complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The invention merges the protection function with the existing transistor structure by using the source and drain of the transistor as charge discharge paths. This combines multiple functions (switching and charge discharge) into a single structure, eliminating the need for separate protection diodes and reducing circuit area while maintaining charge discharge capacity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The transistor structure is designed to serve multiple functions: it acts as both a switching element and a charge discharge path. The source and drain regions are configured to discharge plasma-induced charges, making the transistor universal in its functionality and eliminating the need for dedicated protection components.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Reliability

If charges are discharged through metal interconnections, then the charge discharge function is achieved, but the metal interconnections may be melted

Engineering Contradiction:

Improvecharge discharge functionVSAvoidmetal interconnection damage

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The invention introduces a buffer structure between the charge discharge path and the metal interconnection. This buffer acts as an intermediary that controls and limits the current flow, preventing excessive current from reaching the metal interconnection and causing damage, while still allowing effective charge discharge.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The protection circuit is designed with pre-configured discharge paths through the transistor source and drain regions. These paths provide a controlled resistance and current limiting effect before charges can discharge through the metal interconnection, cushioning the impact and preventing thermal damage to the interconnection.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Data Source

PatentUS8405151B2Protection circuit for semiconductor device

Publication Date: 2013.03.26 SK HYNIX INC

AI summary

A protection circuit for a semiconductor device includes a first gate electrode formed on a substrate of a first conductivity type, and a source and a drain of a second conductivity type having an opposite polarity to the first conductivity type. The source and the drain are commonly coupled to a ground voltage terminal, and the first gate electrode is coupled to a power supply voltage terminal.