臺灣博碩士論文加值系統

本論文示範並驗證超薄單晶矽片或SiO2/Si上預先製作圖形化刻痕，再繼續使用KOH水溶液蝕刻後，可形成超薄的陰影遮罩；另外，我們也證實以KOH水溶液蝕刻超薄單晶矽片時，可照射光線以加強蝕刻速率。
實驗結果顯示，在超薄單晶矽片或SiO2/Si上先以小型研磨鑽頭加工約數微米刻痕後，繼續使用KOH水溶液蝕刻，可得到超薄的陰影遮罩。該陰影遮罩可用於硬式遮罩(hard mask)，在高溫的環境下可抵擋離子植入、X光、電漿蝕刻與化學蝕刻。
除此之外，實驗也發現，在150瓦鹵素燈距離樣本約20公分之內照射後，量測各種不同濃度KOH水溶液蝕刻矽晶片的薄片厚度；實驗中計算後發現，照光增強蝕刻率對於KOH 50%（50~60oC）達 +85.5%，對KOH 60%（50~60oC）也達 +52.4%。照光增強蝕刻率對於KOH 50%（90~100oC）僅增強 15.1%，對KOH 60%（90~100oC）也僅提升6.01%。我們認為高溫KOH因為蝕刻速率可能已經接近飽和值，因此照光能再提升的蝕刻率相對有限所致。
我們相信本論文所提出的技術未來可以持續開發，實際應用於半導體製程技術上。

This thesis demonstrates and verifies that ultra-thin single-crystal silicon wafers or SiO2/Si substrates can be pre-scratched to form engraved patterns and then etched with KOH to form ultra-thin shadow masks; in addition, we also confirmed that the etching rate of ultra-thin monocrystalline silicon with KOH can be enhanced by light illumination. The shadow mask can be used as a hard mask to resist ionization, X-ray, plasma etching and chemical etching in high temperature environments.
In addition, the experiment also found that after the 150W halogen lamp was irradiated within about 20 cm from the sample, the KOH etching rates on silicon substrate was apparently enhanced. The enhancement for 50% KOH solution (50~60oC) can reach 85.5%, the same for KOH 60% (50~60oC) also can reach +52.4%. Nevertheless, the enhancement gave only 15.1% for KOH 50% (90~100oC), and only 6.01% for KOH 60% (90~100oC). We believe that the etching rates of high temperature KOH solutions may have been very close to a saturation value, so the etching rates that can be further improved by illumination are relatively limited.
We believe that the technology proposed in the thesis can be continuously developed in the future and practically applied to semiconductor process technology.

致謝 II
摘要
Abstract IV
目錄 V
圖目錄 VII
表目錄 X
第一章 緒論 1
1.1 前言 1
1.2 文獻回顧 2
1.3 研究動機與目的 4
1.4 論文架構 5
第二章 基本原理 6
2.1 矽的材料特性 6
2.2 濕蝕刻與乾蝕刻 7
2.3 非等向性蝕刻與等向性蝕刻 8
2.4 KOH蝕刻矽的原理與特性 9
2.4.1 溫度與濃度對蝕刻速率的影響 9
2.4.2 KOH對矽不同晶面的蝕刻速率 10
第三章 實驗流程與量測儀器 12
3.1 基本單晶矽薄片的製備 12
3.2 薄片上雕刻後蝕刻形成陰影遮罩 13
3.3 直接利用鍍有二氧化矽的矽單晶刻畫製作陰影遮罩 13
3.4 照光對蝕刻速率的影響 13
第四章 結果與討論 14
4.1 預先雕刻圖形製作超薄矽陰影遮罩 14
4.1.1 實驗與結果 14
4.1.2 超薄陰影遮罩的製作機制 15
4.2 直接利用鍍有二氧化矽的矽單晶刻畫製作陰影遮罩 16
4.2.1 實驗與結果 16
4.2.2 可能的機制探討 17
4.3 照光對蝕刻速率的影響 18
4.3.1 雷射照光增強KOH蝕刻矽單晶 18
4.3.2 照光增強KOH蝕刻矽單晶 20
4.3.3 照光對增強KOH蝕刻矽的速率可能機制探討 21
第五章 結論 23
參考文獻 24

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