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The Wright Etch is a preferential etch for revealing defects in (100) and (111) oriented, p- and n-type silicon. It was developed by Margaret Wright Jenkins in 1976 while working in research and development at Motorola Inc. It was published in 1977.〔Margaret Wright Jenkins, Journal of the Electrochemical Society 124, 757- 759, (1977)〕 This etchant reveals clearly defined oxidation-induced stacking faults, dislocations, swirls and striations with minimum surface roughness or extraneous pitting. These defects are known causes of shorts and current leakage in finished semiconductor devices (such as transistors) should they fall across isolated junctions. A relatively low etch rate (~1 micrometre per minute) at room temperature provides etch control. The long shelf life of this etchant allows the solution to be stored in large quantities. The present report summarizes the highlights of the Wright etch. For a detailed discussion of observation and findings, please consult the original publication.〔Margaret Wright Jenkins, Journal of the Electrochemical Society 124, 757- 759, (1977)〕 ==Etch formula== The composition of the Wright etch is as follows: 60 ml conc. HF (hydrofluoric acid) 30 ml conc. HNO3 (nitric acid) 30 ml of 5 mole CrO3 (mix 1 gram of chromium trioxide per 2 ml of water; the numbers are suspiciously round because the molecular weight of chromium trioxide is almost exactly 100) 2 grams Cu (NO3)2 . 3H2O (copper nitrate) 60 ml conc. CH3COOH (acetic acid) 60 ml H2O (deionized water) In mixing the solution, the best results are obtained by first dissolving the copper nitrate in the given amount of water; otherwise the order of mixing is not critical. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Wright etch」の詳細全文を読む スポンサード リンク
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