SBIR Phase I: Low-Cost Monolithic Semiconductor Structures for Photovoltaic/Photoelectrolysis Splitting of Water for Hydrogen Generation

这个小型企业创新研究第一阶段项目将探索、演示和开发用于制氢的半导体单片光伏/光电化学（PV-PEC）设备的成本效益设计和生产技术。这项工作的动机是最近报道了一种在单晶砷化镓衬底上由金属有机化学气相沉积制成的12.5%效率的实验室装置。据估计，要使这项技术具有经济效益，成本必须降低一个数量级。这种方法是基于III-V型化合物半导体的选择性外延生长，通过简单的闭间隙蒸汽输运和溶液生长过程在大晶粒多晶硅片材料上。基于GaAs， InP， InGaP和GaN在多晶硅上异质外延的电池将被评估。与晶体管、光电二极管、激光器和led等其他半导体器件相比，PV-PEC电池结构简单，这使得所提出的选择性外延工艺在以低成本和高通量加工实现高材料质量方面具有特别优势。这种方法将在不显著牺牲性能的情况下降低所需的成本。这是一个中等到高风险的项目，寻求经济上可行的、清洁的、可再生的制氢过程。

This Small Business Innovative Research Phase I Project will explore, demonstrate, and develop cost-effective designs and production technologies for semiconductor monolithic photovoltaic/photoelectrochemical (PV-PEC) devices for hydrogen production. This work is motivated by the recent report of a 12.5% efficient laboratory device made by metalorganic chemical vapor deposition on a single-crystal GaAs substrate. It is estimated that an order of magnitude cost reduction is necessary to make this technology economic. This approach is based on selective epitaxial growth of III-V compound semiconductors by simple closed-spaced vapor transport and solution growth processes on a large-grain polycrystalline silicon sheet material. Cells based on heteroepitaxy of GaAs, InP, InGaP and GaN on polycrystalline silicon will be evaluated. The simple structure of PV-PEC cells relative to other semiconductor devices such as transistors, photodiodes, lasers, and LEDs, makes the proposed selective epitaxy process especially advantageous in achieving high material quality at low cost with high-throughput processing. This approach will yield the needed cost reductions without significantly sacrificing performance.This is a moderate- to high-risk payoff project that seeks an economically viable, clean, renewable process for hydrogen generation.