Suspended Lens Layer for Semiconductor Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor devices with integrated lenses face challenges in accurate alignment and contamination during fabrication, and require complex assembly systems, which hinders the reduction of photonic semiconductor layer size and improves responsivity/emissivity and speed.
Innovation Solution
A semiconductor device with a substrate, photonic semiconductor layer, and a lens layer where the lens portion is suspended by a cavity in the insulator layer, allowing direct formation of the lens layer on the device and eliminating the need for separate molding and complex alignment systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a lens is separately molded and bonded to the substrate, then the lens can be formed with precise geometry, but the alignment complexity and contamination risk increase significantly
Solution Approach 1:
The patent merges the lens formation process with the semiconductor device fabrication process by depositing the lens layer directly on the device structure using CVD or PECVD. This integration eliminates the need for separate lens molding and bonding steps, thereby reducing alignment complexity and contamination risk while maintaining manufacturing precision through direct in-situ deposition
Solution Approach 2:
The lens layer is deposited preliminarily during the semiconductor fabrication process before final device assembly. By forming the lens structure early in the fabrication sequence on the insulator layer, the alignment is inherently determined by the fabrication lithography patterns, eliminating the need for complex post-fabrication alignment systems
2Manufacturing precision
If a lens is separately molded and bonded to the substrate, then the lens can be formed with precise geometry, but the contamination risk increases
Solution Approach 1:
The patent combines the lens formation with the semiconductor device fabrication in a single integrated process. The lens layer is deposited directly on the device structure using CVD or PECVD techniques within the same cleanroom environment, eliminating the need for separate lens molding and bonding operations that would expose the device to contamination risks from external handling and assembly
Solution Approach 2:
The lens structure is self-formed through direct deposition on the device, with its position and geometry automatically determined by the underlying device structure and lithography patterns. This self-alignment mechanism eliminates the need for external alignment systems and reduces contamination from manual handling and complex assembly procedures
3Area of stationary object
If a lens is used to focus light onto a smaller diode, then the surface area is reduced, but the lens integration complexity increases
Solution Approach 1:
The patent merges the lens layer with the semiconductor device fabrication process by depositing it directly on the insulator layer using CVD or PECVD. This integration allows the lens to be formed simultaneously with the device structure, enabling light focusing onto a smaller photodiode area without adding significant integration complexity
Solution Approach 2:
The lens structure automatically aligns itself with the photodiode through the underlying device geometry and lithography patterns. This self-alignment mechanism enables the lens to focus light onto a reduced photodiode surface area without requiring complex external alignment systems or increasing overall device integration complexity
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 accurate lens alignment without contamination, reduces the size of the photonic semiconductor layer, and enhances the device's responsivity/emissivity and speed by focusing light onto a smaller area, thereby improving performance.
Implementation Method 1
a lens of higher refractive index refracts more strongly and is able to focus light onto a smaller diode
Implementation Method 2
the first insulator layer includes a cavity coaxially aligned with the lens portion, wherein perimeter of the cavity is at least equal to perimeter of the lens portion
Data Source
AI summary
The present invention relates in one aspect to a semiconductor device (10), comprising a substrate (11), a photonic semiconductor layer (12), a first insulator layer (13) above the photonic semiconductor layer (12), and a lens layer (14) on top of the first insulator layer (13). A method for fabricating the semiconductor device is also disclosed. The method comprises the steps of forming a substrate, forming a photonic semiconductor layer on the substrate, forming a first insulator layer above the photonic semiconductor layer, and forming a lens layer on top of the insulator layer.