Semiconductor Edge Terminal Structure for Stable Breakdown Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor devices face challenges in maintaining a stable breakdown voltage due to fluctuations, particularly in structures with P type guard rings around N type semiconductor substrates, such as IGBTs, where improving breakdown voltage is essential but difficult to achieve consistently.
Innovation Solution
A semiconductor device design featuring a semiconductor substrate with a bulk donor of a first conductivity type, an edge terminal structure with high concentration regions, and guard rings of a second conductivity type, where hydrogen peak portions and high concentration regions are strategically placed to enhance breakdown voltage stability by controlling the depletion layer spread.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a P type guard ring is provided in an outer peripheral part of an N type semiconductor substrate, then breakdown voltage is improved, but breakdown voltage fluctuation increases
Solution Approach 1:
The patent introduces a first high concentration region with donor concentration higher than the bulk donor concentration, creating a localized area with different electrical properties. This local quality change allows the depletion layer to be properly terminated at the edge terminal structure portion, improving breakdown voltage stability without sacrificing the breakdown voltage enhancement provided by the guard ring structure.
Solution Approach 2:
The patent changes the donor concentration parameter by introducing a first high concentration region with donor concentration higher than the bulk donor concentration. This parameter change affects the depletion layer distribution and termination, enabling stable breakdown voltage while maintaining the breakdown voltage improvement achieved through the guard ring configuration.
2Strength
If guard rings are provided to improve breakdown voltage, then device performance is enhanced, but manufacturing complexity increases
Solution Approach 1:
The patent combines the first high concentration region with the edge terminal structure portion, merging multiple functions into a single integrated structure. This merging approach maintains the breakdown voltage improvement benefits of guard rings while reducing manufacturing complexity by eliminating the need for separate, complex edge terminal structures.
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 proposed design effectively reduces breakdown voltage fluctuations and improves the overall stability of the semiconductor device by precisely managing the depletion layer, leading to enhanced performance and reliability.
Implementation Method 1
The first high concentration region may be arranged on the upper surface side of the semiconductor substrate, and have a hydrogen peak portion where a hydrogen concentration shows a peak in a hydrogen concentration distribution in a depth direction
Data Source
AI summary
A fabrication method for a semiconductor device includes measuring a thickness of a semiconductor substrate in which a bulk donor of a first conductivity type is entirely distributed, adjusting an implantation condition in accordance with the thickness of the semiconductor substrate and implanting hydrogen ions from a lower surface of the semiconductor substrate to an upper surface side of the semiconductor substrate, and annealing the semiconductor substrate and forming, in a passage region through which the hydrogen ions have passed, a first high concentration region of the first conductivity type in which a donor concentration is higher than a doping concentration of the bulk donor.