Bonded semiconductor light-receiving device and method for manufacturing bonded semiconductor light-receiving device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bonded semiconductor light-receiving devices face issues with mechanical strength due to thermal expansion coefficient mismatches between different materials, leading to delamination and breakage, especially in InP-based devices, which are also costly and brittle.
Innovation Solution
A bonded semiconductor light-receiving device with an epitaxial layer and a support substrate bonded via a bonding material layer, featuring an uneven pattern on the device-functional layer's bonding surface, enhancing bonding force and preventing delamination and breakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If different materials are bonded together to create functional substrates, then device functionality is improved, but thermal expansion coefficient mismatches cause delamination and breakage
Solution Approach 1:
The patent introduces an intermediate layer with specific physical properties (thermal expansion coefficient介于InP和Si之间, refractive index介于InP和封装材料之间) to bridge the parameter mismatch between InP device layer and Si support substrate. This parameter transition approach resolves the thermal expansion coefficient mismatch problem while maintaining device functionality.
Solution Approach 2:
The patent uses an intermediate layer as a mediator between the InP device-functional layer and Si support substrate. This intermediate layer acts as a buffer that compensates for the large difference in thermal expansion coefficients between InP and Si, preventing delamination and breakage during temperature changes.
2Strength
If InP substrate thickness is increased to improve mechanical strength, then device reliability is improved, but manufacturing cost increases significantly
Solution Approach 1:
The patent introduces a Si support substrate as an intermediate mechanical strength provider. The Si substrate with thickness of 50-200 μm provides the necessary mechanical strength and rigidity, allowing the InP device layer to be thin (1-10 μm) and reducing the need for expensive thick InP substrates.
Solution Approach 2:
The patent creates a composite structure combining InP device layer with Si support substrate and intermediate layer. This composite material approach leverages the advantages of both materials: InP for device functionality and Si for mechanical strength and cost-effectiveness.
3Productivity
If chip size is increased to improve light-receiving sensitivity, then device performance is improved, but mechanical strength decreases due to thin chip structure
Solution Approach 1:
The patent uses a composite structure where the Si support substrate provides mechanical strength to the overall chip, enabling larger chip sizes (50-200 μm thickness) without compromising structural integrity. This allows the InP device layer to be optimized for light-receiving sensitivity.
Solution Approach 2:
The Si support substrate acts as a mechanical mediator that provides the necessary strength and rigidity for large-area chips, decoupling the mechanical strength requirement from the thin InP device layer and enabling larger chip sizes for improved light-receiving sensitivity.
4Device complexity
If direct bonding between InP and Si is performed, then manufacturing process is simplified, but bonding fails due to large thermal expansion coefficient difference
Solution Approach 1:
The patent introduces an intermediate layer as a bonding mediator between InP and Si. This intermediate layer has thermal expansion properties that bridge the gap between InP and Si, enabling successful bonding without the large stress that would occur in direct bonding.
Solution Approach 2:
The patent uses an intermediate layer with intermediate thermal expansion coefficient to create a gradual parameter transition from InP to Si, avoiding the abrupt parameter change that causes bonding failure in direct bonding scenarios.
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 device exhibits excellent mechanical strength and suppresses light reflection at the bonding interface, maintaining high light-receiving efficiency.
Implementation Method 1
bonded to the epitaxial layer via a bonding material layer
Implementation Method 2
suppresses light reflection at the bonding interface
Data Source
AI summary
A bonded semiconductor light-receiving device including an epitaxial layer to serve as a device-functional layer, and a support substrate made of a material different from that of the device-functional layer and bonded to the epitaxial layer via a bonding material layer. The device-functional layer has a bonding surface with an uneven pattern formed thereon.