Infrared Optical Semiconductor Cell Layout for Carrier Injection Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical semiconductor elements designed for infrared light emission or reception face challenges in maintaining carrier injection/extraction efficiency and increasing light emission/receiving efficiency per unit area, particularly due to reduced efficiency when emitting or receiving light with wavelengths longer than 3 μm.
Innovation Solution
The optical semiconductor element features a substrate with multiple cells, each having an optical layer and semiconductor layers arranged in a rectangular shape, with electrical connections via wiring portions that surround the optical layer, allowing for efficient carrier injection/extraction and increased light emission/receiving efficiency per unit area. The cells are connected in series to manage current uniformly and reduce capacitance, with termination cells and dummy pad cells enhancing connectivity and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the element area is increased to improve light emission/receiving efficiency per unit area, then the light emission/receiving efficiency per unit area improves, but the carrier injection/extraction efficiency is reduced
Solution Approach 1:
The patent divides the semiconductor element into multiple independent cells, each with its own optical layer and contact structure. This segmentation allows each cell to maintain optimal carrier injection/extraction efficiency while collectively achieving high light emission/receiving efficiency per unit area through parallel operation of multiple cells.
2Productivity
If multiple cells are arranged to increase light emission/receiving efficiency per unit area, then the light emission/receiving efficiency per unit area improves, but the device complexity increases
Solution Approach 1:
The patent merges multiple cells into a single integrated element with shared substrate and coordinated contact structures. The contact structures are designed to extend between adjacent cells, creating a unified electrical connection system that simplifies the overall device architecture while maintaining the benefits of multiple cells.
3Ease of manufacture
If the contact structure is simplified to reduce device complexity, then the ease of manufacture improves, but the carrier injection/extraction efficiency is reduced
Solution Approach 1:
The contact structures serve multiple functions simultaneously: they provide electrical connection between adjacent cells, extend to surround portions of the optical layer to enhance carrier injection/extraction efficiency, and facilitate simplified fabrication through their continuous extended design. This multi-functionality resolves the contradiction between manufacturing simplicity and performance.
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 effectively suppresses reductions in carrier injection/extraction efficiency and enhances light emission/receiving efficiency per unit area, while minimizing current requirements and noise, and facilitates easier external circuit connections.
Implementation Method 1
a plurality of light emitting cells each having an active layer are formed on the substrate... the optical layer is the active layer that generates light having a central wavelength of 3 μm or more and 10 μm or less
Implementation Method 2
the optical layer is the absorption layer having a maximum sensitivity wavelength of 3 μm or more and 10 μm or less
Data Source
AI summary
An optical semiconductor element includes a substrate and a plurality of cells. Each cell includes an optical layer, a first semiconductor layer, and a second semiconductor layer. The plurality of cells include a first cell and a second cell. The second semiconductor layer of the first cell and the first semiconductor layer of the second cell are electrically connected to each other by a first connection portion of a first wiring portion. The first wiring portion has a first extending portion that extends from the first connection portion so as to surround four side portions of the optical layer of the first cell. The optical layer is an active layer that generates light having a central wavelength of 3 μm or more and 10 μm or less or an absorption layer having a maximum sensitivity wavelength of 3 μm or more and 10 μm or less.