High-Voltage LED Chip Structure for Better Light Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional high-voltage LED chips experience poor light-emitting efficiency due to light absorption by adjacent units and layers, limiting their performance in terms of brightness and efficiency.
Innovation Solution
The design includes a substrate with patterned structures and trenches between light-emitting units, featuring conductive structures and insulators to enhance light extraction and reduce internal reflections, with specific angles and shapes of side walls to improve electrical connectivity and light extraction efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If multiple light-emitting units are arranged adjacent to each other on a single substrate to achieve high voltage operation and compact size, then the chip can operate at low current and high voltage with large output power, but the light emitted from adjacent light-emitting units is absorbed by neighboring units or intermediate layers, resulting in poor light-emitting efficiency
Solution Approach 1:
The patent extracts the light extraction function from the conventional planar structure by introducing three-dimensional patterned structures (such as cones, pillars, or gratings) on the substrate surface and between light-emitting units. These extracted structures serve to refract and reflect light, reducing absorption by adjacent units and improving overall light extraction efficiency while maintaining the compact high-voltage chip design.
2Area of stationary object
If light-emitting units are arranged closely together to reduce chip size, then compactness is achieved, but light absorption by adjacent units increases, reducing light extraction efficiency
Solution Approach 1:
The patent transitions from a two-dimensional planar arrangement to a three-dimensional structure by introducing vertical patterned elements (cones, pillars, gratings) on the substrate surface. This dimensional change allows light to be redirected in multiple directions, reducing mutual absorption between closely spaced light-emitting units while maintaining compact chip footprint.
3Ease of manufacture
If conventional planar structures are used between light-emitting units, then manufacturing is simple, but light absorption by intermediate layers reduces light-emitting efficiency
Solution Approach 1:
The patent changes the geometric parameters of the substrate surface and intermediate structures from flat planar forms to three-dimensional patterns with specific dimensions, angles, and spacing. These parameter changes enable the structures to function as optical elements that refract and reflect light, reducing absorption by intermediate layers while remaining compatible with standard semiconductor manufacturing processes.
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 light extraction efficiency by refracting and reflecting light, reducing internal reflections, and ensuring reliable electrical connections between units, thereby improving the overall brightness and efficiency of the light-emitting device.
Implementation Method 1
a conductive structure, formed on the second side wall and electrically connecting the first light-emitting unit and the second light-emitting unit
Implementation Method 2
This configuration enhances light extraction efficiency by refracting and reflecting light
Implementation Method 3
This configuration enhances light extraction efficiency by refracting and reflecting light
Data Source
AI summary
A light-emitting device, includes a substrate, including an upper surface; a first light emitting unit and a second light emitting unit, formed on the upper surface, wherein each of the first light emitting unit and the second light emitting unit includes a lower semiconductor portion and an upper semiconductor portion; and a conductive structure electrically connecting the first light emitting unit and the second light emitting unit; wherein the lower semiconductor portion of the first light emitting unit includes a first sidewall and a first upper surface; and wherein the first side wall includes a first sub-side wall and a second sub-side wall, an obtuse angle is formed between the first sub-side wall and the first upper surface and another obtuse angle is formed between the second sub-side wall and the upper surface.