Silicon Carbide Channeling Implant for Uniform Deep Doping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor manufacturing methods face challenges in precisely controlling the orientation of silicon carbide layers relative to ion beams for effective doping, leading to imperfections in doped region formation and penetration depth.
Innovation Solution
The method involves orienting silicon carbide layers to specific crystal channel directions with a deviation angle of less than ±1° relative to the ion beam, utilizing phosphorous or nitrogen implantation to create doped regions with controlled channeling effects, resulting in a vertical distribution profile with a reduced ratio of maximum to minimum dopant concentration in the vertical extension region.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If ion implantation is performed without precise crystal orientation control, then the doping process is simpler to perform, but the penetration depth and homogeneity of dopant distribution deteriorate
Solution Approach 1:
The patent applies parameter changes by precisely controlling the crystal orientation angle (within ±1° of the <110> direction) and implantation energy parameters to achieve optimal channeling effects. This precise parameter control transforms the doping process to produce homogeneous dopant distribution at controlled penetration depths, directly resolving the contradiction between manufacturing precision and device complexity.
Solution Approach 2:
The patent employs preliminary action by pre-aligning the silicon carbide crystal orientation to the <110> direction before ion implantation. This preliminary orientation step ensures that subsequent implantation automatically achieves the desired channeling effect and homogeneous dopant distribution, making the overall process more controllable despite the added alignment step.
2Manufacturing precision
If channeling implantation is used to enhance penetration depth, then dopant distribution homogeneity improves, but crystal damage increases
Solution Approach 1:
The patent uses parameter changes by optimizing the implantation energy and dose parameters when performing channeling implantation along the <110> direction. By carefully selecting these parameters, the patent achieves homogeneous dopant distribution while minimizing crystal damage, effectively resolving the contradiction between manufacturing precision and harmful effects.
Solution Approach 2:
The patent applies the blessing in disguise principle by utilizing the channeling effect itself - which naturally causes deeper penetration and potential crystal damage - but controlling it through precise angular alignment (±1° of <110> direction). This controlled channeling transforms what could be harmful uncontrolled damage into beneficial homogeneous dopant distribution at the desired depth.
3Reliability
If higher activation annealing temperatures are used to activate dopants, then dopant activation is more complete, but thermal damage and device complexity increase
Solution Approach 1:
The patent applies preliminary action by performing precise channeling implantation that creates optimal dopant distribution and minimal crystal damage before annealing. This preliminary precise implantation reduces the complexity and temperature requirements of the subsequent activation annealing step, allowing effective dopant activation at lower temperatures while maintaining reliability.
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 enhances the penetration depth and homogeneity of dopant distribution, reducing crystal damage and allowing for lower activation annealing temperatures, while maintaining the blocking capability of edge termination regions in semiconductor devices.
Implementation Method 1
implanting phosphorous into the silicon carbide layer using the first ion beam to define a first doped region
Implementation Method 2
orienting a silicon carbide layer to a first crystal channel direction relative to a first ion beam... A deviation angle between the first crystal channel direction and the first ion beam is less than ±1°
Data Source
AI summary
A method includes orienting a silicon carbide layer to a first crystal channel direction relative to a first ion beam and implanting phosphorous into the silicon carbide layer using the first ion beam to define a first doped region in the silicon carbide layer. A deviation angle between the first crystal channel direction and the first ion beam is less than ±1° and the first crystal channel direction comprises a <0001> direction or a <11-23> direction.