Semiconductor Light Emitting Device With Integrated ESD Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor light emitting devices face challenges in achieving uniform current distribution and high light emission efficiency, especially in large-area devices, and are susceptible to damage from electrostatic discharges (ESD) due to limitations in electrode design and separate diode packaging.
Innovation Solution
A semiconductor light emitting device structure is developed with an integrated ESD protection diode, featuring a semiconductor laminate divided into light emitting and protection regions by a separation groove, with contact holes and electrodes designed for efficient current distribution and ESD protection, and a support substrate for conductivity, allowing for improved light extraction and reduced electrode surface area.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a separate protection diode is added to protect against ESD, then reliability is improved, but device complexity increases and product size increases
Solution Approach 1:
The patent merges the protection diode function with the main light emitting device by forming the protection diode in the same semiconductor substrate. The n-type semiconductor layer and p-type semiconductor layer are shared between the main device and protection diode, eliminating the need for separate packaging and reducing device complexity while maintaining ESD protection capability.
Solution Approach 2:
The semiconductor substrate serves multiple functions: it acts as the base for the main light emitting device and simultaneously provides the structure for the integrated protection diode. The shared semiconductor layers (n-type and p-type) enable both light emission and ESD protection functions within a single device structure.
2Productivity
If electrode structure is added to achieve uniform current distribution in large-area devices, then productivity is improved, but light emission efficiency deteriorates due to light absorption by electrodes
Solution Approach 1:
The patent moves the electrode structure from the light emission surface to the opposite surface of the semiconductor laminate. By forming electrodes on the surface opposite to the light emission surface, the electrodes can provide current distribution uniformity without interfering with light extraction, thus eliminating the trade-off between productivity and light emission efficiency.
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
The integrated ESD protection diode enhances light emission efficiency and protects the device from high voltage events, while minimizing product size and electrode-related light loss, achieving uniform current distribution and increased output.
Implementation Method 1
an active layer able to emit light by the recombination of electrons and holes between and together with a p-type semiconductor and an n-type semiconductor
Implementation Method 2
A semiconductor light emitting device may be exposed to a momentary high voltage such as an electrostatic discharge (ESD) while operating the device
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A semiconductor light emitting device has a semiconductor laminate including first and second conductivity type semiconductor layers respectively providing first and second main surfaces and an active layer. The semiconductor laminate is divided into first and second regions. At least one contact hole is formed to pass through the active layer from the second main surface of the first region. A first electrode is formed on the second main surface to be connected to the first conductivity type semiconductor layer of the first region and the second conductivity type semiconductor layer of the second region. A second electrode is formed on the second main surface of the first region to be connected to the second conductivity type semiconductor layer of the first region and the first conductivity type semiconductor layer of the second region.