Semiconductor Terminating Structure With Multi-Layer Field Plates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor devices face insufficient withstand voltage due to electric field concentration at the end portion of the active portion's terminating structure, which can lead to avalanche carrier generation and potential destruction during reverse recovery operations.
Innovation Solution
A semiconductor device design featuring a terminating structure with guard rings and field-plate layers arranged to mitigate electric field concentrations, where the field-plate layers overhang on both sides and the widths and spaces between them are optimized to shift the maximum electric field peak to the edge side, accompanied by a withstand capability structure to prevent carrier injection and heat generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional terminating structure is provided to mitigate electric field concentration at the end portion of the active portion, then the electric field distribution is improved, but the withstand voltage remains insufficient due to residual electric field concentration
Solution Approach 1:
The patent extends the field-plate structure from a single layer to multiple layers stacked in the vertical dimension. The first field-plate layer is positioned at a first height from the front surface, and the second field-plate layer is positioned at a second height greater than the first height. This multi-layer vertical arrangement creates a three-dimensional electric field distribution that more effectively mitigates electric field concentration at the end portion compared to conventional single-layer structures, thereby improving withstand voltage.
Solution Approach 2:
The patent implements a nested structure where the first field-plate layer and second field-plate layer are vertically stacked, with each layer containing guard rings and field plates that are nested within the overall terminating structure. The field plates extend from the front surface through the interlayer dielectric film to reach the second field-plate layer, creating a nested arrangement where inner components are surrounded by outer components. This nested configuration allows the electric field to be distributed and controlled more effectively across multiple levels.
2Reliability
If field-plate layers are added to mitigate electric field concentration, then electric field distribution improves, but device complexity increases
Solution Approach 1:
The patent designs the field-plate structure to serve multiple functions simultaneously. The field plates extend through the interlayer dielectric film to electrically connect with the second field-plate layer, thereby achieving both electric field mitigation and electrical connectivity. The guard rings in both layers provide both field control and potential electrical connections. This multi-functionality reduces the need for separate components, thereby limiting the increase in device complexity while still improving reverse recovery withstand capability.
Solution Approach 2:
The patent merges the functions of multiple field-plate layers into a unified terminating structure. The first and second field-plate layers are electrically connected through the field plates that extend through the interlayer dielectric film, creating a combined structure that acts as a single integrated field control system. The guard rings in both layers are also merged into the overall terminating structure, providing coordinated field control across multiple levels without requiring separate independent systems.
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 design effectively reduces electric field concentrations at the active portion, preventing avalanche carrier flow into the withstand capability structure, enhancing reverse recovery withstand capability and enabling low-loss, high-speed switching operations.
Implementation Method 1
In an electric field distribution of the front surface side of the terminating structure, during rated operation (voltage application), an electric field at an end portion of the active portion side may be smaller than a maximum value of an electric field distribution of the front surface side
Implementation Method 2
Conventional semiconductor devices face insufficient withstand voltage due to electric field concentration at the end portion of the active portion's terminating structure, which can lead to avalanche carrier generation and potential destruction during reverse recovery operations
Data Source
AI summary
A semiconductor device is provided comprising an active portion and a terminating structure. The semiconductor device is provided comprising the active portion provided in the semiconductor substrate and a terminating structure provided at a termination of the front surface side of the semiconductor substrate and that mitigates an electric field of the termination. In the electric field distribution of the front surface side of the terminating structure, during rated voltage application, an electric field at the end portion of the active portion side may be smaller than a maximum value of an electric field distribution of the front surface side. In addition, the electric field distribution of the terminating structure may have a maximum peak of the electric field on the edge side opposite to the active portion with respect to a center of the terminating structure.