Radiation-Emitting Semiconductor Chip Layout for Uniform Current Spreading
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radiation emitting semiconductor chips face challenges in achieving homogeneous brightness and good quantum efficiency due to inhomogeneous current density and series resistances in the semiconductor layer sequences.
Innovation Solution
The semiconductor chip is designed with a specific structure that includes a carrier with epitaxial semiconductor layer sequences of different conductivity types, current spreading layers, a dielectric layer, a reflective layer, and electrically insulating layers to manage current density and radiation emission efficiently.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If conventional semiconductor chip structures are used, then manufacturing is simpler, but brightness homogeneity and quantum efficiency deteriorate due to inhomogeneous current density
Solution Approach 1:
The chip structure is segmented into multiple functional layers including a first current spreading layer, second current spreading layer, dielectric layer, reflective layer, and electrically insulating layer. Each layer performs a specific function in managing current distribution and enhancing light extraction, thereby achieving homogeneous brightness through structured segmentation rather than a monolithic design.
Solution Approach 2:
Different regions of the chip are assigned different material properties and functions. The current spreading layers have specific conductivity characteristics, the dielectric layer provides insulation and structural support, the reflective layer enhances light extraction in specific directions, and contact structures are positioned at optimized locations. This local differentiation of properties enables homogeneous current density distribution and improved brightness uniformity.
2Loss of energy
If conventional current spreading methods are used, then device complexity is lower, but quantum efficiency deteriorates due to series resistances
Solution Approach 1:
The current spreading function is divided between multiple specialized layers: a first current spreading layer in direct contact with the active region, a second current spreading layer, and a reflective layer. This segmentation allows each layer to be optimized for its specific function, reducing overall series resistance and improving quantum efficiency compared to a single-layer approach.
Solution Approach 2:
The dielectric layer and electrically insulating layer act as intermediaries between the current spreading layers and other chip components. These intermediary layers provide electrical insulation while maintaining thermal and mechanical stability, enabling efficient current management without introducing additional series resistance that would reduce quantum 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
This configuration results in a homogeneous current density and improved quantum efficiency, ensuring that the semiconductor chip emits electromagnetic radiation with enhanced brightness and efficiency.
Implementation Method 1
An active region may be arranged between the first semiconductor layer sequence and the second semiconductor layer sequence. The active region is configured to generate electromagnetic radiation emitted from the radiation exit surface during operation. The active region may have a pn junction for generating the electromagnetic radiation
Implementation Method 2
a reflective layer (10) arranged between the second current spreading layer (8) and the carrier (3)
Data Source
AI summary
A radiation emitting semiconductor chip may be configured to emit electromagnetic radiation from a radiation exit surface during operation. The chip may include a carrier on which a first epitaxial semiconductor layer sequence of a first conductivity type and a second epitaxial semiconductor layer sequence of a second conductivity type different from the first conductivity type are arranged, a first current spreading layer arranged between the first semiconductor layer sequence and the carrier, a second current spreading layer arranged between the first current spreading layer and the carrier, a dielectric layer arranged in regions between the first current spreading layer and the second current spreading layer, a reflective layer arranged between the second current spreading layer and the carrier, and an electrically insulating layer arranged in regions between the second current spreading layer and the reflective layer.