论文标题
通过湿蚀刻方法从散装块底物中的低于10微米厚的GE薄膜
Sub-10-micron thick Ge thin films from bulk-Ge substrates via a wet etching method
论文作者
论文摘要
低缺陷密度的GE薄膜在基于GE的光学设备（光学探测器，LED和激光器）中与SI电子设备集成的低成本，高度集成的光子电路至关重要。在这项工作中，通过表面形态，缺陷密度和可实现的厚度研究了用四种不同溶液制备的GE薄膜。基于纳米条的溶液（1：1：10）和基于HCl的溶液（1：1：5）都能够在53小时内将比10微米的GE薄膜湿润535微米厚的散装基板湿润。对于基于纳米的溶液的相应RMS表面粗糙度为32 nm，基于HCl的溶液为10 nm。根据HRXRD结果，在蚀刻过程之前和之后保留了批量质量的质量。在湿蚀刻的过程中保持了6000-7000 cm-2的低螺纹位错密度，而无需引入额外的缺陷。这种方法提供了一种廉价且方便的方法来制备低于10微米厚的GE薄膜，从而实现了对低缺陷密度基于GE的设备的未来研究，例如光电探测器，LED和激光器。
Low-defect-density Ge thin films are critical in Ge based optical devices (optical detectors, LEDs and Lasers) integrated with Si electronic devices for low-cost, highly integrated photonic circuits. In this work, Ge thin films prepared by wet etching with four different solutions were studied in terms of the surface morphology, defect density and achievable thickness. Both nanostrip-based solution (1:1:10) and HCl-based solution (1:1:5) were able to wet-etch 535 micron thick bulk-Ge substrates to Ge films thinner than 10 micron within 53 hours. The corresponding RMS surface roughness was 32 nm for the nanostrip-based solution and 10 nm for the HCl-based solution. The good quality of bulk-Ge was preserved before and after the etching process according to the HRXRD results. The low threading dislocation density of 6000-7000 cm-2 was maintained in the process of wet etching without introducing extra defects. This approach provides an inexpensive and convenient way to prepare sub-10-micron thick Ge thin films, enabling future studies of low-defect-density Ge-based devices such as photodetectors, LEDs, and lasers.
