Optoelectronic Semiconductor Chip Codopant Activation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional activation methods for optoelectronic semiconductor chips, particularly for buried p-doped layers, are ineffective in achieving high p-type conductivity due to the diffusion barrier preventing codopant removal, leading to increased operating voltage in components like LEDs.
Innovation Solution
A method involving forming a semiconductor layer sequence with doped functional layers containing bonding complexes of dopants and codopants, where energy is introduced to break these complexes, allowing the codopant to remain and bond at different locations, thereby avoiding compensation and increasing free charge carriers without codopant removal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional thermal annealing is used to activate dopant, then electrical conductivity is improved, but codopant cannot be removed from buried layers due to diffusion barriers
Solution Approach 1:
The patent extracts the harmful codopant from the semiconductor layer by creating an opening in the diffusion barrier through a localized annealing process. This allows the codopant to be driven out from buried doped layers without requiring complete removal of the barrier structure, thereby resolving the contradiction between maintaining barrier integrity and enabling codopant removal.
Solution Approach 2:
The patent applies preliminary action by creating a localized opening in the diffusion barrier before performing the annealing process. This preparatory step enables subsequent codopant removal from buried layers that would otherwise be inaccessible, while the rest of the barrier remains intact to protect other regions.
2Reliability
If high temperature annealing is applied to activate buried p-doped layers, then dopant activation is improved, but crystal quality degradation occurs
Solution Approach 1:
The patent applies local quality by concentrating the high temperature annealing effect only in the localized region where the diffusion barrier opening exists. This allows dopant activation in the buried layer at the opening site while the rest of the crystal structure remains at lower temperature, preventing widespread crystal quality degradation.
Solution Approach 2:
The patent segments the annealing process into a localized region (at the diffusion barrier opening) and the surrounding areas. This spatial segmentation enables selective dopant activation where needed while preserving crystal quality in regions where high temperature would be harmful.
3Stability of the object's composition
If diffusion barrier is maintained intact to protect layer structure, then structural stability is improved, but codopant cannot be removed from buried layers
Solution Approach 1:
The patent performs preliminary action by creating a localized opening in the diffusion barrier before annealing. This allows codopant removal from buried layers to proceed while the majority of the diffusion barrier remains intact, maintaining structural stability in protected regions.
Solution Approach 2:
The patent applies local quality by modifying the diffusion barrier only in the specific location where codopant removal is needed. The localized opening provides a controlled pathway for codopant extraction while the rest of the barrier continues to provide structural protection and prevent unwanted diffusion.
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 method enhances the electrical conductivity of the semiconductor chip, reducing the operating voltage and enabling effective activation of previously unactivatable buried doped layers, such as those in LEDs.
Implementation Method 1
activating the dopant by breaking open the bonding complexes by introducing energy
Implementation Method 2
The electrical activation of such codoped semiconductor materials is usually achieved by the activation in the form of a purely thermal annealing step
Implementation Method 3
for the codopant to be able to be driven out from the doped semiconductor layer to a certain degree or completely, that is to say for example from 0.001% to 100%, by the thermal annealing step
Data Source
AI summary
An optoelectronic semiconductor chip includes a semiconductor layer sequence having at least one doped functional layer having at least one dopant and at least one codopant, wherein the semiconductor layer sequence includes a semiconductor material having a lattice structure, one selected from the dopant and the codopant is an electron acceptor and the other an electron donor, the codopant is bonded to the semiconductor material and/or arranged at interstitial sites, and the codopant at least partly forms no bonding complexes with the dopant.