Surface-Emitting Laser Contact Layout for Single-Peak Beam Profiles

Solution Overview

Problem

Surface-emitting semiconductor lasers face challenges in improving beam radiation characteristics, particularly in achieving single-peak intensity distribution profiles and efficient current injection, leading to suboptimal oscillation modes and output power.

Innovation Solution

A surface-emitting semiconductor laser design with a contact region area smaller than the current injection region, enhancing current density at the center and facilitating low-order transverse mode oscillation, which includes a substrate, light reflection layers, an active layer, a current confining layer, and electrodes, with the contact region strategically sized to concentrate current density.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the contact region area is made smaller than the current injection region area, then current density at the center is increased and low-order transverse mode oscillation is facilitated, but the device complexity increases due to the need for precise area control

Engineering Contradiction:

Improvebeam radiation characteristicsVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The contact region is designed with a specific area that is smaller than the current injection region area, creating a localized quality difference. This local area reduction concentrates current density at the center of the current injection region, which facilitates low-order transverse mode oscillation and improves beam radiation characteristics without requiring complex overall structural changes

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention changes the geometric parameter of the contact region area relative to the current injection region area. By controlling the contact region area to be smaller than the current injection region area, the current density distribution is modified, shifting the oscillation mode to low-order transverse modes and improving beam radiation characteristics

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the contact region area is made smaller than the current injection region area, then single-peak intensity distribution profile is achieved, but manufacturing precision requirements increase

Engineering Contradiction:

Improvebeam radiation characteristicsVSAvoidarea control precision

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The contact region is designed with a specific area that is smaller than the current injection region area, creating a localized quality difference. This local area reduction concentrates current density at the center of the current injection region, which facilitates low-order transverse mode oscillation and improves beam radiation characteristics without requiring complex overall structural changes

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention changes the geometric parameter of the contact region area relative to the current injection region area. By controlling the contact region area to be smaller than the current injection region area, the current density distribution is modified, shifting the oscillation mode to low-order transverse modes and improving beam radiation characteristics

Inventive Principle:

Principle #35Parameter changes

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 improves beam radiation characteristics by enabling single-peak intensity distribution profiles and high output power while reducing the complexity of connecting multiple stacked structures, increasing yield and reliability, and allowing for flexible light output adjustment.

Implementation Method 1

the area of the contact region is smaller than the area of the current injection region. This makes it possible to increase current density around a center of the current injection region

Methodology Applied

Scientific EffectCurrent density concentration:

Implementation Method 2

a first light reflection layer provided over the substrate, a second light reflection layer provided over the substrate, with the first light reflection layer being interposed between the second light reflection layer and the substrate

Methodology Applied

Scientific EffectLight reflection: Reflection

Data Source

PatentUS12068581B2Surface-emitting semiconductor laser

Publication Date: 2024.08.20 SONY SEMICON SOLUTIONS CORP

AI summary

A surface-emitting semiconductor laser includes a substrate, a first electrode in contact with the substrate, a first light reflection layer over the substrate, a second light reflection layer over the substrate, with the first light reflection layer between the second light reflection layer and the substrate, an active layer between the second light reflection layer and the first light reflection layer, a current confining layer between the active layer and the second light reflection layer and includes a current injection region, a second electrode over the substrate, with the second light reflection layer between the second electrode and the substrate, at least a portion of the second electrode is at a position overlapping the current injection region, and a contact layer between the second electrode and the second light reflection layer and includes a contact region in contact with the second electrode.