Selective area formation of arsenic oxide-rich octahedral microcrystals during photochemical etching of n-type GaAs
Selective area formation of arsenic oxide-rich octahedral microcrystals during photochemical etching of n-type GaAs
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DOI：
10.1364/ome.8.000289
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发表时间：
2018-02
影响因子：
2.8
通讯作者：
Aditi Udupa;Xin Yu;Lonna Edwards;L. Goddard
中科院分区：
文献类型：
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作者：
Aditi Udupa;Xin Yu;Lonna Edwards;L. Goddard
我们展示了在硫酸快速数字投影光化学(PC)刻蚀过程中，如何在高掺杂n型GaAs衬底的选择区域内对八面体氧化砷微晶的形成进行空间定域。我们拍摄了一段时间推移的视频，显示这些类似晶体的八面体结构生长到不同的尺寸，从5微米到100微米。通过一系列不同的研究，我们确定了刻蚀速度、光照面积、酸类型和衬底质量是影响晶体形成的主要因素。特别是，我们观察到这些结构只在高刻蚀速率的晶片照明区形成。此外，它们只有在光照面积足够大的情况下才会形成。当使用盐酸时，这些结构形成，但随后部分溶解。最后，我们观察到了优质晶片的单个微晶的生长，但机械晶片的微晶网络的形成。
We demonstrate how to spatially localize the formation of octahedral arsenic oxide microcrystals in selective areas of highly doped n-type GaAs substrates during rapid digital projection photochemical (PC) etching with sulfuric acid. We captured a time lapse video that shows that these crystal-like octahedral structures grow to various sizes ranging from 5 µm to 100 µm. By conducting a series of different studies, we identified the etch rate, the area of illumination, the acid type, and the substrate quality as major factors that affect crystal formation. In particular, we observed that the structures only formed in the high etch rate illuminated regions of the wafer. Moreover, they only formed when the area of illumination was adequately large. The structures formed but then partially dissolved when hydrochloric acid was used. Lastly, we observed the growth of individual microcrystals for prime grade wafers but the formation of a network of microcrystalline features for mechanical grade wafers.