Semiconductor Laser Barrier Metal Layer for Uniform Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for fixing semiconductor laser chips on support substrates using scrubbing techniques often result in uneven reaction layers due to the interaction between bonding materials and electrode materials, leading to uneven stress distribution and variations in the polarization direction of laser light, which is undesirable for applications like DVDs.
Innovation Solution
A semiconductor laser device with a second barrier metal layer that does not react with the bonding material, ensuring a uniform reaction layer formation and reducing stress on the optical waveguide, thereby maintaining consistent polarization characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If scrubbing method is used to fix semiconductor laser chip on support substrate, then bonding strength is improved, but reaction layer uniformity deteriorates causing polarization characteristic degradation
Solution Approach 1:
A barrier metal layer is introduced as an intermediary between the electrode material and the bonding material. This barrier layer prevents direct reaction between the bonding material and electrode material, ensuring uniform reaction layer formation while maintaining strong bonding. The barrier metal layer acts as a mediator that controls the interaction between the two materials.
Solution Approach 2:
The electrode structure is designed as a composite material system with multiple layers including the barrier metal layer and the electrode material. This composite structure combines the advantages of different materials: the barrier metal layer provides reaction control and uniformity, while the electrode material provides electrical conductivity and bonding strength.
2Reliability
If bonding material reacts with electrode material to form reaction layer, then bonding is achieved, but stress distribution on optical waveguide becomes uneven
Solution Approach 1:
The barrier metal layer serves as a mediator that controls the reaction between bonding material and electrode material. By limiting the reaction to occur only at the interface between bonding material and barrier metal layer, the reaction layer thickness is uniformly controlled, resulting in even stress distribution on the optical waveguide while maintaining reliable bonding.
Solution Approach 2:
The thickness of the barrier metal layer is precisely controlled within a specific range (50-200 nm) to optimize the reaction layer formation. By adjusting this parameter, the reaction layer thickness is controlled to be within 100 nm, achieving uniform stress distribution while ensuring adequate bonding strength.
3Manufacturing precision
If barrier metal layer is added to control reaction, then reaction layer uniformity is improved, but device structure becomes more complex
Solution Approach 1:
The barrier metal layer thickness is optimized within a specific range (50-200 nm) to achieve the desired reaction layer uniformity. By controlling this parameter, the invention achieves uniform reaction layer formation without requiring excessively thick or complex multi-layer structures, thus limiting the increase in device complexity.
Solution Approach 2:
The electrode structure is designed as a composite material system with the barrier metal layer and electrode material. This composite structure integrates the barrier function and electrical conductivity function in a unified structure, avoiding the need for separate barrier structures and reducing overall device 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
The uniform reaction layer and reduced stress on the optical waveguide result in improved polarization characteristics with smaller variations in the direction of polarization, enhancing the performance of semiconductor laser devices.
Implementation Method 1
heat is applied, so that a junction layer is formed by interaction between the electrode material and the bonding material
Implementation Method 2
a junction layer is formed by interaction between the electrode material and the bonding material
Implementation Method 3
resonator (optical waveguide) for generating the laser
Data Source
AI summary
An opto-semiconductor device. An opto-semiconductor element includes a semiconductor substrate, a multilayered semiconductor layer formed on a first surface of the semiconductor substrate and having a resonator, a first electrode with multiple conductive layers formed on the multilayered semiconductor layer, and a second electrode formed on a second surface of the semiconductor substrate. A support substrate has a first surface formed with a fixing portion having a conductive layer for fixing the first electrode connected thereto through a bonding material. Bonding material and conductive layers forming the first electrode react to form a reaction layer. The difference in thermal expansion coefficient between semiconductor substrate and support substrate is not more than ±50%. A second barrier metal layer not reactive with bonding material is formed inside the first electrode uppermost conductive layer, while uppermost layer reacts with the bonding material to form the reaction layer.