Power MOSFET Edge Ring with Auto-Aligned Deep Implant
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The formation of edge termination regions in semiconductor devices, particularly in SiC, is limited by the use of hard masks which cause planarity issues and restrict the minimum separation distance between implanted regions.
Innovation Solution
An electronic device and manufacturing method that utilize intentionally damaged regions with an amorphous lattice structure to form edge termination regions, allowing for auto-aligned implantation without the need for hard masks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If hard masks are used to form edge termination regions, then implantation depth control is improved, but planarity problems occur and minimum separation distance between implanted regions increases
Solution Approach 1:
The patent applies preliminary action by forming a damaged region (amorphous layer) in the semiconductor substrate before the implantation step. This pre-damaged region serves as a template that guides the subsequent ion implantation, eliminating the need for hard masks. The damaged region is created through a first implantation step that introduces damage without the mask, then a second implantation step follows the damage pattern to form the edge termination regions with precise depth control.
Solution Approach 2:
The patent introduces an intermediary element - the damaged region (amorphous layer) - that acts as a mediator between the implantation process and the final doping profile. This damaged region serves as a self-aligned mask that guides ion penetration depth and spatial distribution, replacing the traditional hard mask and eliminating planarity issues while maintaining precise implantation control.
2Manufacturing precision
If hard masks are used to form edge termination regions, then implantation depth control is improved, but the mutual spatial distance between adjacent implants is restricted
Solution Approach 1:
The patent creates the damaged region pattern before implantation, allowing the subsequent implantation to follow this pre-established pattern. This preliminary damaged region acts as a self-aligned guide that enables closer spacing of adjacent implanted regions without requiring hard masks, thereby reducing the minimum spatial distance between implants while maintaining depth control.
Solution Approach 2:
The damaged region serves as an intermediary that enables closer spacing of implanted regions. By using the damaged region as a self-aligned template rather than physical hard masks, the patent eliminates the spatial constraints imposed by mask thickness and processing margins, allowing adjacent implant regions to be placed closer together.
3Length of stationary object
If ion implant is performed along crystallographic axes, then penetration depth is increased, but channeling effects cause non-uniform doping profiles
Solution Approach 1:
The patent applies preliminary action by creating a damaged region (amorphous layer) before the final implantation step. This pre-damaged region disrupts the crystallographic structure and eliminates channeling effects, allowing subsequent ions to implant uniformly without following crystal axes. The preliminary damage serves as a barrier that prevents deep channeling while maintaining controlled penetration depth.
Solution Approach 2:
The patent converts the harmful channeling effect into a beneficial controlled implantation process. By intentionally creating a damaged region first, the patent transforms the potential harm of channeling into a controlled mechanism where the damaged region serves as a depth-limiting barrier. This allows the ion beam to penetrate to the desired depth without excessive channeling, achieving both depth control and uniform doping profiles.
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 approach enables the formation of edge termination regions with precise control over implantation depth and conductivity, overcoming planarity issues and allowing for closer spacing of implanted regions.
Implementation Method 1
performing a channeled implant of doping species having a second electrical conductivity in the damaged region
Implementation Method 2
the so-called channeling may considerably increase the penetration depth of the ions into the crystalline material with respect to an amorphous target
Implementation Method 3
a damaged region extending at a portion of the semiconductor body between the first sub-region and the second sub-region, facing the front side, the damaged region having an amorphous lattice structure
Data Source
AI summary
The present description provides a method for manufacturing an electronic device. An example method comprises: arranging a semiconductor body of N-type, having a lattice structure with spatial symmetry; forming, in the semiconductor body, a damaged region having an amorphous lattice structure or lattice structure with no spatial symmetry; forming an edge termination region of P-type in the semiconductor body including performing a channelized implant of P-type doping species at the damaged region and at portions of the semiconductor body adjacent to the opposite sides of the damaged region.