Transparent Conductive Oxide Interconnection for Substrate Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of multilayer semiconductor, glass, or ceramic composites, such as multilayer photovoltaic cells, is limited by the incompatibility of lattice structures, leading to defects and reduced efficiency in converting light into electrical energy, restricting the number of active layers, wavelength optimization, and material usage due to lattice structure compatibility issues.
Innovation Solution
The method involves bonding substrates instead of growing layers, allowing for the production of layers with different properties by optimizing growth substrates for interconnection using transparent conductive oxides like ITO, with a direct bonding method and plasma activation, enabling electrically conductive and optically transparent interconnection layers that are durable and temperature-resistant.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If layers are grown directly on one another, then the lattice structure compatibility is required, but this limits the number of attainable active layers and material choices
Solution Approach 1:
The invention divides the layer structure into separate substrates that are bonded together. Each substrate can be grown independently on optimized growth substrates, allowing different materials and lattice structures without direct contact between incompatible layers. The substrates are segmented into first substrate with first layer, second substrate with second layer, and interconnection layer, enabling versatile material selection while maintaining structural integrity through bonding interfaces.
2Productivity
If direct layer growth is used, then lattice structure optimization is possible, but this reduces the number of attainable active layers to maximum two to three layers
Solution Approach 1:
The invention transitions from vertical direct growth to a multi-substrate bonding approach, adding the dimension of substrate separation. Multiple active layers can be stacked by bonding separate substrates together, enabling more than two to three layers while maintaining high quality through independent growth optimization on each substrate before bonding.
3Ease of manufacture
If substrates are bonded with conventional methods, then structural connection is achieved, but electrical conductivity and optical transparency are not simultaneously provided
Solution Approach 1:
The invention uses a composite interconnection layer comprising transparent conductive oxide (such as ITO - indium tin oxide) that simultaneously provides electrical conductivity and optical transparency. This composite material enables the bonding interface to fulfill multiple functions: mechanical connection, electrical conduction, and light transmission, allowing optimization for specific wavelength ranges while maintaining structural integrity.
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 allows for the efficient production of multilayer composites with improved efficiency, increased layer diversity, and the use of favorable materials like silicon or germanium, achieving high electrical conductivity and optical transparency while minimizing defects and enhancing the conversion of light into electrical energy.
Implementation Method 1
a direct bonding method with plasma activation
Data Source
AI summary
This invention relates to a method for bonding of a first contact area of a first at least largely transparent substrate to a second contact area of a second at least largely transparent substrate, on at least one of the contact areas an oxide being used for bonding, from which an at least largely transparent interconnection layer is formed with an electrical conductivity of at least 10e1 S/cm2 (measurement: four point method, relative to temperature of 300K) and an optical transmittance greater than 0.8 (for a wavelength range from 400 nm to 1500 nm) on the first and second contact area.