Semiconductor Laser Device Epi Intermediate Layer Cleaving
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor laser devices face challenges in substrate breakage during chip separation due to process mesa grooves, particularly in regions of reduced thickness, which affects yield and high-temperature characteristics.
Innovation Solution
Incorporating an epi intermediate layer made of a compound semiconductor containing As, such as InGaAsP, AlGaInAs, or InGaAs, on the substrate to facilitate easy breakability along separating sections, thereby preventing substrate breakage during chip separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If process mesa grooves are formed by dry etching to improve yield, then manufacturing precision is improved, but substrate breakage occurs in reduced thickness portions during cleaving
Solution Approach 1:
The patent applies local quality by forming a thick buffer layer (5-20 μm) specifically in the separating sections where cleaving occurs, while maintaining the process mesa grooves in the laser element regions. This localized thickening provides mechanical support exactly where needed during substrate division, preventing breakage in reduced thickness portions without affecting the manufacturing precision of the process mesas.
Solution Approach 2:
The patent implements preliminary action by pre-forming the thick buffer layer in separating sections before the cleaving process. This advance preparation ensures that when cleaving occurs, the substrate has already been reinforced at critical locations, preventing unexpected breakage during the division process while maintaining the integrity of the laser element structures.
2Speed
If resonator length is shortened to 200 microns or less to increase relaxation-vibration frequency for high-speed response, then speed is improved, but substrate breakage risk increases due to reduced structural support
Solution Approach 1:
The patent applies local quality by strategically placing thick buffer layers only in the separating sections between laser elements, not throughout the entire substrate. This allows the laser elements to maintain short resonator lengths (200 μm or less) for high-speed response while the localized buffer layer reinforcement prevents substrate breakage during cleaving, resolving the contradiction between speed optimization and structural strength.
3Productivity
If chip size is shrunk to improve yield, then productivity is improved, but substrate breakage becomes more likely due to smaller margin for error
Solution Approach 1:
The patent implements local quality by forming thick buffer layers (5-20 μm) specifically in the separating sections, providing targeted reinforcement where cleaving occurs. This allows chip size to be reduced to improve yield while the localized reinforcement ensures substrate strength is maintained at critical points, preventing breakage even with smaller chips and reduced manufacturing margins.
Data Source
AI summary
A semiconductor laser device includes a substrate, a buffer layer provided on an upper surface of the substrate and formed of InP, a laser element having a ridge structure formed above the buffer layer, and an epi intermediate layer formed of a compound semiconductor containing As and exposed to the outside.