Electrostatic Protection Structure for Bidirectional High-Voltage ESD
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional high-voltage electrostatic protection structures lack consistency in forward and reverse ESD protection capabilities, failing to effectively withstand high voltages in both directions.
Innovation Solution
An electrostatic protection structure comprising a substrate with buried layers and deep wells of specific conductivity types, forming PN junctions and PNP transistors to enable bidirectional electrostatic discharge protection, with heavily doped regions connected as electrodes to manage voltage biases and prevent latch-up effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple deep wells with different conductivity types are introduced, then bidirectional ESD protection is achieved, but device complexity increases
Solution Approach 1:
Multiple protection functions are merged into a single integrated structure. The first, second, third, and fourth deep well regions are combined within one continuous structure, sharing common substrate and burial layer interfaces. This merging approach achieves bidirectional ESD protection without requiring separate protection structures for forward and reverse directions
Solution Approach 2:
The electrostatic protection structure is designed with multi-functionality to handle both forward and reverse voltage conditions through a single unified structure. The symmetric arrangement of deep well regions with alternating conductivity types enables the same structure to provide protection regardless of voltage polarity, eliminating the need for separate protection mechanisms
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
The structure achieves consistent bidirectional electrostatic discharge protection with higher voltage withstand capabilities and reduced latch-up effects, ensuring effective electrostatic protection in both forward and reverse voltage modes.
Implementation Method 1
the first heavily doped region, the first well region and the second heavily doped region together form a first PNP transistor; the third heavily doped region, the second well region and the fourth heavily doped region together form a second PNP transistor
Implementation Method 2
forming PN junctions and PNP transistors to enable bidirectional electrostatic discharge protection
Data Source
AI summary
The present application relates to an electrostatic protection structure and a preparation method therefor. The electrostatic protection structure comprises a substrate, a buried layer, a first deep well, a second deep well and a third deep well. A well region of the opposite conductivity type and a heavily doped region of the same conductivity type are provided in the first deep well, and well regions and heavily doped regions of the same conductivity type are respectively provided in the second deep well and the third deep well. The first deep well, a first well region and a second well region are floating; a first heavily doped region leads out electrostatic voltage; and a sixth heavily doped region is grounded.