LED Current Blocking Patterns Prevent Electrode Edge Damage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Light emitting diodes (LEDs), particularly those with high driving voltage, are prone to damage due to current crowding at the edges of electrodes, leading to instability, especially in ultraviolet LEDs.
Innovation Solution
Incorporating current blocking patterns on the conductive semiconductor layers overlapping the edges of electrode pads, formed through techniques like ion implantation, to prevent current concentration and enhance stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If high driving voltage is used in ultraviolet LEDs, then light emission performance is improved, but current crowding damage at electrode edges occurs
Solution Approach 1:
A current blocking layer is introduced as an intermediary element between the electrode pad and the semiconductor layer. This layer acts as a mediator that redistributes the current flow, preventing direct current concentration at the electrode edges while maintaining the high driving voltage operation. The current blocking layer with controlled resistance value serves as a buffer that equalizes current distribution across the electrode-semiconductor interface.
Solution Approach 2:
The current blocking layer is selectively positioned only at critical regions where current crowding occurs, such as around the electrode pad edges. The layer's resistance value is specifically optimized for the local electrical conditions at the electrode-semiconductor interface. This localized application ensures that current redistribution occurs precisely where needed without affecting the overall device performance or requiring complete structural modification.
2Reliability
If current blocking patterns are added to prevent current crowding, then electrode stability is improved, but device complexity increases
Solution Approach 1:
The current blocking layer is implemented by modifying electrical parameters (resistance value) rather than fundamentally changing the device structure. By controlling the resistance value of the current blocking layer within specific ranges, the patent achieves current redistribution without adding complex multi-layer structures or sophisticated geometric patterns. This parameter-based approach simplifies manufacturing while effectively preventing current crowding.
3Stability of the object's composition
If current blocking layer with specific resistance is used, then current distribution is improved, but manufacturing precision requirements increase
Solution Approach 1:
The patent specifies optimal resistance value ranges for the current blocking layer that provide effective current redistribution while accommodating normal manufacturing variations. By defining broader acceptable ranges rather than requiring precise single-value control, the patent reduces manufacturing precision requirements. The resistance value is controlled within practical fabrication capabilities to achieve the desired current distribution effect.
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 implementation of current blocking patterns effectively prevents edge damage from current crowding, thereby improving the stability and longevity of high-voltage ultraviolet LEDs.
Implementation Method 1
the first current blocking pattern may be formed in the first conductive semiconductor layer and the second current blocking pattern may be formed in the second conductive semiconductor layer through an ion implantation scheme
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
Disclosed are a light emitting device (100) and a light emitting device package (700). The light emitting device (100) includes a light emitting structure (110) including a first conductive semiconductor layer (112), an active layer (114) on the first conductive semiconductor layer (112) and a second conductive semiconductor layer (116) on the active layer (114); a first electrode pad (151) on the first conductive semiconductor layer (112); a second electrode pad (152) on the second conductive semiconductor layer (116); and a current blocking pattern (161, 162) overlapping an edge of at least one of the first and second electrode pads (151, 152).