Microwave Annealing for Semiconductor Defect Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In semiconductor device manufacturing, high-temperature annealing is required to cure crystal defects, but this can lead to impurity diffusion in peripheral circuit regions, degrading the performance of semiconductor elements, while low-temperature microwave annealing may not effectively cure defects, especially in deep regions.
Innovation Solution
Applying microwave annealing to the semiconductor substrate to heat it uniformly, allowing for effective curing of crystal defects at lower temperatures, thereby preventing impurity diffusion and maintaining the integrity of semiconductor elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high-temperature annealing is performed to cure crystal defects, then the crystal defects are effectively cured, but impurity diffusion occurs in peripheral circuit regions degrading semiconductor element performance
Solution Approach 1:
The invention changes the heating method from conventional thermal annealing to microwave heating, fundamentally altering the physical parameter of heat application. Microwave heating enables selective heating of the semiconductor substrate at lower temperatures while still achieving effective curing of crystal defects, thus preventing impurity diffusion in peripheral circuits while maintaining defect curing effectiveness
Solution Approach 2:
The invention replaces the conventional thermal conduction-based annealing system with a microwave electromagnetic field-based heating system. This substitution allows for more precise and uniform heating control, enabling effective defect curing without the excessive temperature rise that causes impurity diffusion in peripheral circuit regions
2Manufacturing precision
If low-temperature microwave annealing is used to prevent impurity diffusion, then impurity diffusion is suppressed, but crystal defects in deep regions are not effectively cured
Solution Approach 1:
The invention dynamically controls the microwave heating parameters including power level, heating time, and frequency to achieve optimal heating效果. By adjusting these dynamic parameters, the system can penetrate deep into the semiconductor substrate to cure defects while maintaining overall temperature control to prevent impurity diffusion
Solution Approach 2:
The invention employs periodic microwave heating cycles with specific duty ratios, allowing the electromagnetic energy to penetrate and heat deep regions of the semiconductor substrate periodically. This periodic action enables effective curing of deep crystal defects while the intermittent nature of heating prevents excessive temperature accumulation that would cause impurity diffusion
3Reliability
If multiple annealing steps are performed to thoroughly cure defects, then defect curing is improved, but manufacturing time and process complexity increase
Solution Approach 1:
The invention extracts and eliminates redundant annealing steps from the manufacturing process. By using microwave heating's unique ability to achieve uniform deep penetration heating, a single microwave annealing step can replace multiple conventional annealing steps, thereby reducing manufacturing cycle time while maintaining or improving defect curing completeness
Solution Approach 2:
The microwave annealing process serves multiple functions simultaneously: it cures crystal defects throughout the substrate depth, activates impurities, and prevents impurity diffusion in peripheral circuits. This multi-functionality in a single step replaces what previously required multiple separate annealing steps, reducing overall manufacturing time
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 method effectively cures crystal defects without causing dislocation or degrading the characteristics of semiconductor elements, improving the performance of the semiconductor device by reducing dark current and maintaining the accuracy of image sensors.
Implementation Method 1
a microwave annealing device, and then performs microwave annealing by applying microwave to the semiconductor substrate to heat the semiconductor substrate
Data Source
AI summary
An improvement is achieved in the performance of a semiconductor device. In a method of manufacturing the semiconductor device, in an n-type semiconductor substrate, a p-type well as a p-type semiconductor region forming a part of a photodiode is formed and a gate electrode of a transfer transistor is formed. Then, after an n-type well as an n-type semiconductor region forming the other part of the photodiode is formed, a microwave is applied to the semiconductor substrate to heat the semiconductor substrate. Thereafter, a drain region of the transfer transistor is formed.