Photovoltaic Absorber Layer Pulse Heating for Defect Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Photovoltaic devices degrade over time due to the formation of compensating defect complexes, leading to reduced efficiency and shortened lifespan, necessitating a method to enhance or recover performance.
Innovation Solution
A system and method involving rapid heating of the absorber layer in photovoltaic devices using high-intensity electromagnetic energy to induce chemical defect reactions, followed by rapid quenching, which dissociates compensating donor complexes and regenerates active charge carriers, thereby restoring the p-type doping and built-in electric field.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of moving object
If photovoltaic devices are operated in field conditions over time, then they generate electrical power continuously, but their performance degrades due to formation of compensating defect complexes
Solution Approach 1:
The patent applies preliminary action by performing a thermal treatment process on the absorber layer during or after device fabrication, before the device is deployed into field conditions. This pre-treatment modifies the defect chemistry and dopant distribution in advance, creating a more stable initial state that resists subsequent degradation from compensating defect complex formation during operation.
Solution Approach 2:
The patent utilizes parameter changes by applying controlled thermal energy to the absorber layer, changing the temperature parameter to induce defect reactions and dopant redistribution. This thermal parameter change modifies the defect chemistry and charge carrier concentration, creating a more stable operational state that maintains performance over time.
2Productivity
If dopant concentration is increased to improve charge carrier concentration, then power output increases, but compensating defect complexes form more readily causing degradation
Solution Approach 1:
The patent applies parameter changes by using thermal treatment to modify the distribution and activation state of dopants in the absorber layer. This controlled thermal parameter change optimizes the dopant concentration profile, increasing effective charge carrier concentration while simultaneously reducing the formation of compensating defect complexes, thus achieving both higher power output and improved stability.
Solution Approach 2:
The patent effectively creates a composite structure within the absorber layer by combining doped semiconductor material with controlled defect structures. The thermal treatment process creates a composite state where activated dopants and modified defect chemistry work together to provide both high charge carrier concentration and resistance to degradation from compensating defect complexes.
3Reliability
If thermal treatment is applied to modify defect chemistry, then charge carrier concentration increases, but excessive heating can cause material degradation
Solution Approach 1:
The patent applies dynamics by using time-dependent thermal treatment with controlled heating rates and specific duration. The dynamic thermal profile allows the system to progress through different defect reaction stages, achieving optimal dopant activation and defect modification while limiting the total thermal exposure time to prevent material degradation. The process dynamically balances beneficial defect chemistry changes against potential thermal damage.
Solution Approach 2:
The patent utilizes periodic action through pulsed or cyclic thermal treatment regimes. Instead of continuous heating, the process applies thermal energy in controlled periods or pulses, allowing beneficial defect reactions to occur during heating phases while providing cooling intervals that prevent cumulative thermal damage. This periodic thermal action achieves the desired charge carrier concentration increase without exceeding material thermal tolerance.
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 approach effectively recovers the performance of photovoltaic devices by increasing the effective charge carrier concentration and power output, extending the device's lifespan and maintaining high performance characteristics over time.
Implementation Method 1
directing electromagnetic energy to an energy side of the module... to heat at least a portion of the absorber layer
Implementation Method 2
heating at least a portion of the absorber layer of the photovoltaic device to a temperature in a range of 200 C to 1000 C
Implementation Method 3
promote at least one dopant chemical reaction in the absorber layer... dissociates compensating donor complexes and regenerates active charge carriers
Data Source
AI summary
According to embodiments provided herein, the performance of photovoltaic device can be improved by rapidly heating an absorber layer of a device in open-circuit to a high temperature for a short period of time followed by rapid quenching. The rapid heating may be accomplished by one or more pulses of high intensity electromagnetic energy. The energy may be visible light. The energy may be absorbed primarily in the absorber layer, such that the absorber layer is preferentially heated, promoting chemical reactions of dopant complexes. The dopant chemical reactions disrupt compensating defect complexes that have formed in the device, and regenerate active carriers.