Multi-Wavelength Laser Annealing for Silicon Substrate Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dynamic surface annealing techniques using a single light source with a limited wavelength spectrum, such as a red laser, may not achieve optimum annealing due to not utilizing the full spectrum of wavelengths, leading to suboptimal thermal processing of silicon substrates.
Innovation Solution
A thermal processing apparatus and method that allows for the use of multiple preselected light sources capable of emitting different wavelengths, which can be indexed to a collimator to focus continuous wave electromagnetic radiation into a line on the substrate, enabling flexible selection of frequency, intensity, and time of exposure to approximate 'white light' for more comprehensive annealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single light source with limited wavelength spectrum is used for dynamic surface annealing, then the device complexity is reduced, but the annealing effectiveness and uniformity deteriorate
Solution Approach 1:
The patent combines multiple light sources with different wavelengths (e.g., red laser at 810 nm, green laser at 532 nm, blue laser at 450 nm) into a single processing system. These multiple light sources are merged to provide a broader spectrum for annealing, improving the effectiveness and uniformity of the thermal processing while maintaining a manageable device structure through integrated control mechanisms.
Solution Approach 2:
The system is designed to perform multiple functions by incorporating light sources across different wavelength ranges (red, green, blue, and potentially ultraviolet). This multi-functional approach allows the same annealing apparatus to handle various material types and annealing requirements, making the system universally applicable while improving overall annealing performance.
2Manufacturing precision
If multiple light sources with different wavelengths are used to approximate white light, then the annealing effectiveness is improved, but the device complexity increases
Solution Approach 1:
The system segments the broad spectrum requirement into discrete wavelength components provided by individual laser sources. Rather than attempting to generate continuous white light, the system uses separate red, green, and blue laser sources that can be independently controlled and combined. This segmentation simplifies the overall system architecture while achieving the goal of broad-spectrum annealing.
Solution Approach 2:
The system incorporates dynamic control mechanisms that allow selective activation of different light sources based on processing requirements. The controller can dynamically adjust which wavelengths are active, their intensities, and their timing, providing flexibility to optimize annealing effectiveness for different materials and conditions without requiring all light sources to operate simultaneously at full power.
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 allows for more uniform and effective annealing across the substrate by utilizing a broader spectrum of wavelengths, improving the thermal processing capabilities and meeting the demands for greater memory capacity, faster switching speeds, and smaller feature sizes in the IC industry.
Implementation Method 1
selecting a plurality of different first electromagnetic radiation wavelengths for thermally processing the substrate
Implementation Method 2
focusing continuous wave electromagnetic radiation into a line of radiation extending at least partially across an upper surface of the substrate to thermally process a first portion of the substrate
Implementation Method 3
indexing a plurality of light sources corresponding to the selected plurality of different first electromagnetic radiation wavelengths to one or more collimators. The method may also comprise focusing continuous wave electromagnetic radiation into a line of radiation
Implementation Method 4
Annealing recreates a crystalline structure from regions of the substrate that were previously made amorphous, and activates dopants by incorporating their atoms into the crystalline lattice of the substrate
Implementation Method 5
diffracting the electromagnetic radiation
Data Source
AI summary
The present invention generally relates to a thermal processing apparatus and method that permits a user to index one or more preselected light sources capable of emitting one or more wavelengths to a collimator. Multiple light sources may permit a single apparatus to have the capability of emitting multiple, preselected wavelengths. The multiple light sources permit the user to utilize multiple wavelengths simultaneously to approximate “white light”. One or more of a frequency, intensity, and time of exposure may be selected for the wavelength to be emitted. Thus, the capabilities of the apparatus and method are flexible to meet the needs of the user.