Browsing by Author "Yang, Cheng-Hao"

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Effects of various ion-typed surfactants on silicon anisotropic etching properties in KOH and TMAH solutions
(Elsevier, 2005-03-28) Yang, Chii-Rong; Chen, Po-Ying; Yang, Cheng-Hao; Chiou, Yuang-Cherng; Lee, Rong-Tsong
Three ion-typed surfactants, including anionic SDSS, cationic ASPEG and non-ionic PEG, which are powerful wetting agents in electroforming, were added to 30 wt.% KOH and 10 wt.% TMAH solutions to evaluate the silicon anisotropic etching properties of the (1 0 0) silicon plane without agitation and no IPA additive. The results indicate that the surfactant ion-types are not the main determinants of the silicon anisotropic etching properties in KOH and TMAH solutions. The wetting capacity of the etchants causes the efficacies of the etchants on the roughness to follow the order anionic SDSS, cationic ASPEG, non-ionic PEG and pure solution in KOH solutions, and the order cationic ASPEG, non-ionic PEG, pure solution and anionic SDSS in TMAH solutions, especially at higher etching temperatures. Moreover, the chemical activities of etchants differ so that the etching rates follow the order anionic SDSS, pure solution, non-ionic PEG and cationic ASPEG in KOH solutions, and the order anionic SDSS, pure solution, cationic ASPEG and non-ionic PEG in TMAH solutions at a given etching temperature. Anionic SDSS has the highest etching rate of 5.4 μm/min and the lowest surface roughness of 7.5 nm, which are about 1.69 times higher and 7.87 times lower, respectively, than those obtained in pure KOH solution. The cationic ASPEG has a reasonable etching rate of 0.7 μm/min and the lowest surface roughness of 4 nm in TMAH solutions for etching temperature of 100 °C. Furthermore, the surfactants used here were demonstrated to allow the utilization of usual mask materials and anionic SDSS can even increase the selectivity of silicon dissolution toward silicon dioxide in KOH solutions. A drastic reduction of the undercutting of the convex corners is obtained in TMAH solutions with non-ionic PEG surfactant. This finding reveals that the addition of non-ionic PEG to TMAH solutions is ideal when accurate profiles are required without extremely deep etching.
Study on anisotropic silicon etching characteristics in various surfactant-added tetramethyl ammonium hydroxide water solutions
(IOP, 2005-09-20) Yang, Chii-Rong; Yang, Cheng-Hao; Chen, Po-Ying
Three ion-typed surfactants, including anionic sodium dihexyl sulfosuccinate (SDSS), cationic ammonium salt of poly(ethylene glycol) (ASPEG) and non-ionic poly(ethylene glycol) (PEG), were added to 10 wt% tetramethyl ammonium hydroxide water (TMAHW) solutions to evaluate the silicon anisotropic etching properties of the (1 0 0) silicon plane without agitation and no isopropyl alcohol (IPA) additive. The results indicate that the wetting capacity of the etchants cause the efficacies of the etchants on the roughness reduction to follow the order cationic ASPEG, non-ionic PEG, pure solution and anionic SDSS in TMAHW solutions, especially at high etching temperatures. Moreover, the chemical activities of the etchants cause the efficacies of the etchants on the etching rates to follow the order anionic SDSS, pure solution, cationic ASPEG and non-ionic PEG in TMAHW solutions at a given etching temperature. The cationic ASPEG has a reasonable etching rate of 0.7 µm min−1 and the lowest surface roughness of 4 nm in TMAHW solutions at an etching temperature of 100 °C. ASPEG and PEG in TMAHW solutions markedly affect aluminum passivation. The undercutting of the convex corners in PEG-added TMAHW solutions can be drastically reduced without using corner compensation; the undercutting ratio obtained using a PEG surfactant is about 45% lower than that obtained in pure TMAHW solution. This finding reveals that non-ionic PEG should be added to TMAHW solutions when accurate profiles are required without extremely deep etching. This study also demonstrated that non-ionic PEG is more appropriate than IPA for anisotropic silicon TMAHW etching.
柯慈小說中的書寫倫理：文學潛能與書寫責任
(2016) 楊承豪; Yang, Cheng-Hao
本論文探討南非小說家柯慈小說中的書寫倫理。在閱讀柯慈的作品時，大多數批評家將書寫和倫理視為二個獨立的概念，認為柯慈的作品具有倫理的面向是因為其作品討論了倫理議題。本論文批判此概念的謬誤。柯慈的書寫本身即是倫理的展現：文學無法被固化而具有重塑現實觀的潛能，而倫理挑戰我們重新思考自我與他者的關係，二者緊密結合。第一章透過閱讀《壞年頭日誌》討論文學的潛能如何去本體化。此文本特殊的結構──每頁分為三層並有三段的不同敘述同時進行──使其成為幾乎無法（以正常方式）閱讀的文本，然而此特殊的寫作結構揭露所有系統的“彷如”狀態 (the “as-if”)。第二章處理書寫責任的問題。責任應被理解成德希達所談的絕對責任。我將閱讀《聖彼得堡的文豪》和《伊莉莎白．卡斯特洛》二個文本，討論柯慈的書寫如何回應他者。第三章探討在《鐵器年代》中柯慈如何書寫無法言說和再現的受苦經驗。然而柯慈並不將受苦視為屬於他者的問題，受苦是全人類共有的經驗，受苦促使我們重新思索自我與他者的倫理關係。最後一章討論《耶穌的童年》中的記憶倫理問題。對柯慈來說，書寫本身就是見證，書寫的倫理性根植於見證歷史中被遺忘的他者和被遺忘的記憶。新的國家建立在和歷史的決裂，記憶歷史卻成為遺忘歷史。此文本促使我們思考，在處理歷史記憶時，是否能不被制式化和實證的價值標準所匡限，而能夠看到記憶最獨一的面向。