LASER Annealing Significantly Improves the Electronic Properties of ITO
Transparent conductive oxide (TCO) layers are an important component of semiconductors and can be found within many electronic devices including solar cells, touchscreens, and light emitting diodes. The ideal TCO exhibits no resistivity while also being completely transparent in the visible light. Currently, indium tin oxide (ITO) is consider the best TCO and is commonly used due its high electrical conductivity and high optical transparency. However, while ITO is very effective as a TCO, its electrical properties can be improved. Decreasing the resistivity of ITO would allow for production of thinner films capable of performing the same function. Thinner films are advantageous because they reduce the cost of production and increases the transparency. Therefore, a facile method to reduce the electrical resistance and increase the optical transparency is needed.
Researchers at ASU have developed a laser annealing process that improves the electrical properties of ITO-based semiconductors. Laser annealing, the process of heating and cooling to strengthen a material, saves time, conserves energy, and improves ITO functionality as compared to conventional 24-hour furnace annealing. laser annealing significantly enhances the electrical properties of ITO in comparison to conventional annealing. Specifically, this process lowers ITO resistivity resulting in lower-cost semiconductors with superior electrical performance. Furthermore, the annealing process is dependent upon the atmospheric composition. Variation of the atmospheric composition leads to subtle differences in resistivity and transparency, which can be tuned based on the application of the material.
• Light Emitting Diodes
• Optoelectronic Devices
• Smart Phone Screens
• Solar Cells
Benefits and Advantages
• Efficient – Laser annealing saves time and energy as compared to conventional furnace annealing.
• Innovative – Improved electrical resistance and overall effectiveness.
• Consistent – Unlike microwave or thermal based annealing laser based annealing results in a consistent improvement in the electrical resistance of the ITO.
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