VCSEL Toothed Top Contact for Emission Mode Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

As the density of VCSELs in an array increases, reducing the separation between them leads to inefficiencies in carrier injection and perturbations in electromagnetic energy distribution, affecting emission patterns, particularly in applications like 3D sensing and imaging systems.

Innovation Solution

A VCSEL configuration featuring a toothed top contact, implanted regions, or segmented top contact segments is used to control the current path and photon energy distribution, optimizing emission modes by constraining the current flow and limiting carrier flow to specific regions, thereby improving emission patterns.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If VCSEL density in array is increased, then productivity is improved, but carrier injection efficiency deteriorates and electromagnetic energy distribution is perturbed

Engineering Contradiction:

ImproveVCSEL array densityVSAvoidcarrier injection efficiency

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The top contact is segmented into multiple discrete contact regions (first, second, third contact regions) arranged in a triangular pattern, which divides the current injection paths and reduces interference between adjacent VCSELs. This segmentation allows higher VCSEL density while maintaining carrier injection efficiency by preventing carrier flow perturbation that would occur with continuous top contacts in high-density arrays.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the VCSEL structure are given different properties: the top contact has segmented regions with specific geometries, the oxide aperture has a defined diameter, and implanted regions are positioned at specific locations. These localized structural variations optimize current distribution and electromagnetic energy confinement in high-density arrays, resolving the contradiction between high VCSEL density and maintained injection efficiency.

Inventive Principle:

Principle #3Local quality

2Productivity

If VCSEL density in array is increased, then productivity is improved, but emission pattern stability deteriorates

Engineering Contradiction:

ImproveVCSEL array densityVSAvoidemission pattern stability

Core Design Contradiction:

ProductivityVSStability of the object's composition

Solution Approach 1:

The segmented top contact structure with triangular arrangement of contact regions stabilizes the emission pattern by creating symmetric current distribution paths. This segmentation prevents electromagnetic energy perturbation that would otherwise occur in high-density arrays, maintaining stable emission patterns even as VCSEL density increases for improved productivity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The triangular arrangement of the three contact regions creates a specific geometric asymmetry that, when combined with the oxide aperture confinement, produces stable radial emission patterns. This deliberate asymmetric geometry in the top contact structure compensates for the perturbations introduced by high VCSEL density, maintaining emission pattern stability.

Inventive Principle:

Principle #4Asymmetry

3Manufacturing precision

If top contact is configured with toothed shape or segments, then emission mode control is improved, but device complexity increases

Engineering Contradiction:

Improveemission mode controlVSAvoidtop contact structure

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The top contact is divided into three discrete contact regions arranged triangularly, which provides precise control over emission modes through defined current paths. While this segmentation increases structural complexity compared to a simple continuous contact, it enables precise emission mode control that is essential for high-quality VCSEL operation in imaging and sensing applications.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The top contact structure incorporates localized geometric features (triangular arrangement of contact regions) that provide precise emission mode control. This localized structural differentiation increases device complexity but enables the manufacturing precision required for controlled emission patterns in high-density VCSEL arrays.

Inventive Principle:

Principle #3Local quality

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 configuration enhances the emission patterns of VCSELs, achieving specific radial symmetries and improving the performance of systems that utilize VCSELs, such as imaging and communications systems, by reducing perturbations and optimizing current injection.

Implementation Method 1

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Implementation Method 2

A perturbation of a carrier distribution may alter an electromagnetic energy distribution, a photon distribution, and/or the like of the VCSEL, which may result in a change to an emission pattern

Methodology Applied

Scientific EffectElectromagnetic energy distribution:

Data Source

PatentUS11451009B2Vertical cavity surface emitting laser mode control

Publication Date: 2022.09.20 WELLS FARGO BANK NA

AI summary

A vertical cavity surface emitting laser (VCSEL) may include a top contact, wherein the top contact is associated with a particular shape, and wherein the particular shape is a toothed shape with a particular quantity of teeth. The VCSEL may include at least one implanted region. The VCSEL may include at least one top contact segment.