Selective Light Array Photolithography for Fast Mask-Less Exposure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current mask-less photolithography systems are inefficient due to long exposure times, limited resolution, and vulnerability to vibrations, making them unsuitable for mass-producing semiconductor substrates without causing damage such as burns or scorching.
Innovation Solution
A photolithography system with a light source array of selectively activatable light emitters that simultaneously exposes the entire substrate surface to a geometric pattern, eliminating the need for a photomask and reducing exposure time by activating only the necessary emitters corresponding to the pattern.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a single laser beam is used for direct write photolithography, then the system can eliminate photomasks and achieve mask-less patterning, but the exposure time becomes extremely long (up to 8 hours for a 150 mm substrate)
Solution Approach 1:
The invention divides the single laser beam into multiple parallel beams using a beam splitter array, creating a multi-beam system that can expose multiple regions of the substrate simultaneously. This segmentation of the light source enables parallel processing, dramatically reducing exposure time while maintaining mask-less operation.
Solution Approach 2:
The invention combines multiple laser beams into a coordinated array that operates simultaneously on different portions of the substrate. By merging the exposure function across multiple beams, the system achieves the exposure of an entire substrate in minutes rather than hours, while preserving the flexibility of mask-less patterning.
2Productivity
If the power or intensity of the laser beam is increased to speed up the exposure process, then the exposure time is reduced, but the beam causes burns or scorching on the wafer
Solution Approach 1:
By segmenting the total light energy across multiple parallel beams, each individual beam delivers lower power density to the substrate, avoiding localized overheating and damage. The distributed beam array achieves fast exposure through parallelism rather than through high-intensity single-point exposure.
Solution Approach 2:
Each beam in the array can be independently controlled with optimized power levels appropriate for its specific exposure region. This allows the system to maintain safe intensity levels across the entire substrate while achieving rapid overall exposure through the coordinated action of multiple beams.
3Device complexity
If a single beam is used for direct write, then the system structure is simpler, but the resolution is limited by the beam width and the process is vulnerable to vibrations during long exposure
Solution Approach 1:
The segmentation of light into multiple narrow parallel beams enables higher resolution patterning, as each beam can be focused to a smaller spot size. The array of segmented beams achieves superior resolution compared to a single wide beam, while the rapid exposure time reduces vulnerability to vibrations.
4Ease of manufacture
If mask-less direct write is used, then photomask costs are eliminated, but the production efficiency is extremely low due to long exposure times
Solution Approach 1:
By merging multiple laser beams into a parallel array system, the invention achieves mass production capability for mask-less photolithography. The combined action of multiple beams exposes entire substrates in minutes, enabling high-volume manufacturing while retaining the cost advantages of mask-less operation.
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 significantly reduces exposure time, improves efficiency, and enhances pattern resolution, allowing for faster and more reliable manufacturing of semiconductor substrates while minimizing the risk of damage.
Implementation Method 1
light beams are uniformly directed to the photomask, with light passing through holes or transparencies in the photomask and onto a photosensitive material on the surface of a substrate, thereby transmitting a pattern on the substrate corresponding to the transparent areas of the mask. The exposure of the photosensitive material on the surface of the substrate to light caused a chemical reaction
Data Source
AI summary
A system, device, and method for imparting or transferring a geometric pattern on the surface of a substrate. The device comprises, a housing forming at least a partially enclosed space, a light source body comprising an array of light emitters, a base disposed below the light source body and configured for supporting the substrate having a photoresist layer thereon, and a controller for activating a predetermined number of individual light emitters corresponding to the predetermined geometric pattern. Each individual light emitter within the array of light emitters is selectively activatable to emit a light. The array of light emitters comprises a plurality of light-emitting diodes, a plurality of quantum dots, or both.