Laser Diode Bar Selective Electrical Contacting

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The production of efficient laser diode bars based on nitride compound semiconductor materials is challenging due to higher defect densities, leading to inefficient emission and increased heating from non-contributory emitters.

Innovation Solution

A method involving the production of laser diode bars with selectively electrically contacted emitters, where only those with optical and electrical properties within a predetermined range are supplied with current, while defective emitters are excluded from the electrical connection to prevent current flow and heating.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If all emitters are electrically contacted and supplied with current, then the laser diode bar can operate, but defective emitters consume current and generate heat without contributing to radiation emission, reducing overall efficiency

Engineering Contradiction:

Improveenergy loss from defective emittersVSAvoidcomplexity of selective electrical contacting

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by testing optical and electrical properties of emitters before final electrical contacting. Emitters are tested during or after growth, and only those meeting specifications are subsequently electrically contacted. This prevents defective emitters from being connected to current supply, eliminating energy waste before operation begins.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements self-service by using the semiconductor structure itself to enable selective contacting. The current supply line is designed to automatically connect only to emitters that meet electrical specifications, allowing the system to self-select functional emitters without external intervention during operation.

Inventive Principle:

Principle #25Self-service

2Productivity

If emitters are tested for optical and electrical properties before electrical contacting, then only functional emitters are supplied with current improving efficiency, but the production process becomes more complex and time-consuming

Engineering Contradiction:

Improveefficiency of laser diode bar operationVSAvoidtime for testing and selective contacting

Core Design Contradiction:

ProductivityVSLoss of time

Solution Approach 1:

Testing of optical and electrical properties is performed during or immediately after the semiconductor layer growth process, before the structure is completed. This preliminary testing allows identification of functional emitters early, so that only those emitters receive final electrical contacting. This approach minimizes time loss by integrating testing into the production flow rather than adding a separate post-processing step.

Inventive Principle:

Principle #10Preliminary action

3Temperature

If defective emitters are electrically contacted, then current flows through them causing heating and reduced efficiency, but excluding them requires additional testing and selection steps

Engineering Contradiction:

Improveheating from defective emittersVSAvoidease of producing laser diode bar

Core Design Contradiction:

TemperatureVSEase of manufacture

Solution Approach 1:

Electrical properties such as threshold current are tested during or after growth to identify defective emitters before final electrical contacting. Emitters exceeding current specifications are identified early and excluded from the current supply line connection, preventing them from operating and generating heat. This preliminary identification simplifies manufacturing by avoiding the need for post-assembly defect detection and management.

Inventive Principle:

Principle #10Preliminary action

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 approach enhances the efficiency of the laser diode bar by reducing current consumption and improving radiation emission by ensuring only functional emitters contribute to the operation, thereby mitigating the effects of manufacturing defects and higher defect densities in nitride compound semiconductor materials.

Implementation Method 1

the emitters each including a semiconductor layer sequence having an active layer that generates laser radiation

Methodology Applied

Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentUS11581707B2Method of producing a laser diode bar and laser diode bar

Publication Date: 2023.02.14 AMS OSRAM INT GMBH

AI summary

A method of producing a laser diode bar includes producing a plurality of emitters arranged side by side, emitters each including a semiconductor layer sequence having an active layer that generates laser radiation, a p-contact on a first main surface of the laser diode bar and an n-contact on a second main surface of the laser diode bar opposite the first main surface, testing at least one optical and/or electrical property of the emitters, wherein emitters in which the optical and/or electrical property lies within a predetermined setpoint range are assigned to a group of first emitters, and emitters in which the at least one optical and/or electrical property lies outside the predetermined setpoint range are assigned to a group of second emitters, and electrically contacting first emitters, wherein second emitters are not electrically contacted so that they are not supplied with current during operation of the laser diode bar.