Conformal Boron Doping for Selective 3D Semiconductor Surfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods of boron doping in semiconductor materials are limited in their ability to conformally dope three-dimensional structures and often inadvertently dope neighboring oxide materials, lacking selectivity and conformality.
Innovation Solution
A method involving the selective deposition of a conformal boron dopant film on semiconductor surfaces using a non-line-of-sight thermal decomposition process, followed by annealing to drive boron atoms into the semiconductor material while minimizing dopant incorporation into oxide materials, ensuring precise and conformal doping of semiconductor materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional doping methods (e.g., implantation) are used, then doping can be achieved, but conformal doping of three-dimensional structures is not possible and line of sight limitations occur
Solution Approach 1:
The patent replaces mechanical implantation methods with a chemical vapor deposition process using gaseous boron precursors. This substitution enables the dopant to reach all surfaces of three-dimensional structures through vapor-phase transport, achieving conformal doping without line-of-sight limitations inherent in mechanical implantation
Solution Approach 2:
The patent utilizes temperature parameter changes to control the deposition and diffusion processes. By maintaining specific temperature ranges during CVD and subsequent annealing, the process achieves conformal film deposition and controlled dopant diffusion into the semiconductor material
2Manufacturing precision
If existing boron doping methods are used, then semiconductor materials can be doped, but neighboring oxide materials are also inadvertently doped
Solution Approach 1:
The patent applies local quality by creating different surface conditions on semiconductor and oxide materials through selective preparation steps. The semiconductor surface is treated to be receptive to boron deposition and diffusion, while oxide surfaces are maintained in a state that prevents dopant incorporation, achieving selective doping at different locations
Solution Approach 2:
The patent performs preliminary surface preparation and selective film deposition before the doping process. By pre-treating semiconductor surfaces and depositing conformal films only where needed, the process prevents dopant contamination of oxide materials before the doping step occurs
3Manufacturing precision
If thermal decomposition process is used at 700-800°C, then conformal dopant film can be deposited by non-line-of-sight process, but high temperature is required
Solution Approach 1:
The patent changes the chemical composition parameters of the precursor gases and adjusts deposition parameters to enable conformal film formation at reduced temperatures. By optimizing the precursor chemistry and deposition conditions, the process achieves conformal coverage without requiring excessively high temperatures
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 effective, selective conformal doping of semiconductor materials, achieving high boron atom concentration within the semiconductor while preventing significant dopant penetration into oxide materials, thus addressing the limitations of existing techniques.
Implementation Method 1
The first surface and the second surface are exposed to a boron precursor at a temperature in a range of about 700° C. to about 800° C. to selectively deposit a conformal dopant film by a non-line-of-sight, thermal decomposition process
Implementation Method 2
The electronic device is annealed with a millisecond anneal at a temperature in a range of about 1150° C. to about 1200° C. to drive boron atoms from the dopant film into the semiconductor material
Implementation Method 3
drive boron atoms from the dopant film into the semiconductor material
Implementation Method 4
The electronic device is annealed to crystallize the additional semiconductor material to form a boron doped crystalline semiconductor material
Data Source
AI summary
A method of selectively and conformally doping semiconductor materials is disclosed. Some embodiments utilize a conformal dopant film deposited selectively on semiconductor materials by thermal decomposition. Some embodiments relate to doping non-line of sight surfaces. Some embodiments relate to methods for forming a highly doped crystalline semiconductor layer.