VCSEL Aperture Structure With Oxide Holes for Emitter Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional VCSEL manufacturing methods face challenges such as increased complexity, electrical disconnection risks, and emitter reliability issues due to trench formation and surface defects, which affect the performance and yield of vertical-cavity surface-emitting lasers.
Innovation Solution
The VCSEL design incorporates an insulation region formed by ion implantation, with oxidation holes in the isolation region to prevent defects from reaching the emitter, and a surface protection layer to insulate the upper mirror, active layer, and lower mirror, thereby preventing electrical disconnection and enhancing reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a ring-shaped trench is formed by etching mirror layers and the active layer to concentrate current, then current concentration in a small aperture is improved, but manufacturing complexity increases
Solution Approach 1:
The patent extracts the harmful trench structure from the device design and replaces it with an oxidation layer formed in a simplified manner. Instead of etching a ring-shaped trench through multiple layers, the invention uses an oxidation process that naturally forms an isolated post structure without requiring complex trench etching, thus maintaining current concentration while reducing manufacturing complexity
Solution Approach 2:
The patent changes the physical and chemical parameters of the device structure by forming an oxidation layer with specific properties (insulating characteristics, mechanical strength) that can serve multiple functions. This oxidation layer replaces the need for complex trench structures while achieving the same current concentration effect through parameter optimization rather than structural complexity
2Manufacturing precision
If a ring-shaped trench is formed to concentrate current, then current concentration is improved, but the risk of electrical disconnection increases
Solution Approach 1:
The patent replaces the permanent trench structure with a sacrificial oxidation layer that serves its purpose during manufacturing and then can be selectively removed or integrated. This approach eliminates the risk of electrical disconnection through trenches while maintaining current concentration, as the oxidation layer provides a controlled, reliable path for current management without creating weak points for disconnection
3Manufacturing precision
If a large area trench is formed around the emitter, then current concentration is achieved, but emitter reliability is adversely affected by surface defects
Solution Approach 1:
The patent applies local quality by forming an oxidation layer with specific properties only in the regions where current concentration is needed, rather than forming a large area trench. This localized oxidation provides the necessary current concentration while minimizing the affected area around the emitter, thus preventing surface defects from compromising emitter reliability
Solution Approach 2:
The oxidation layer acts as an intermediary structure that mediates between the requirement for current concentration and the need to protect emitter reliability. Instead of directly etching trenches that expose the emitter to surface defects, the oxidation layer provides a controlled intermediate structure that achieves current concentration while protecting the emitter from harmful surface effects
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 design effectively prevents electrical disconnection and emitter degradation by isolating the oxidation process, ensuring high reliability and improved manufacturing yield of vertical-cavity surface-emitting lasers.
Implementation Method 1
an insulation region formed by ion implantation
Implementation Method 2
including an oxidation layer and a window layer surrounded by the oxidation layer
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
A vertical-cavity surface-emitting laser (VCSEL) according to one embodiment of the present disclosure comprises: a lower mirror; an upper mirror; an active layer interposed between the lower mirror and the upper mirror; an aperture forming layer interposed between the upper mirror and the active layer and having an oxide layer and a window layer surrounded by the oxide layer; and a plurality of oxide holes penetrating through the upper mirror and the aperture forming layer, wherein the upper mirror comprises an insulating region formed by ion implantation and an isolated region surrounded by the insulating region, and the plurality of oxide holes are arranged in the isolated region.