| 摘要: | 在矽晶圓製造流程中，經過切片(Slicing)、晶邊圓磨(Edge Contouring)的程序後，矽晶圓的表面會產生鋸痕(Saw Mark)及損傷層(Damaged Layer)而影響到後續的矽晶圓加工製作流程，因此本研究嘗試利用自行研發的熱熔膠研磨墊搭配游離碳化矽磨料對矽晶圓脆性材料進行研磨加工，使矽晶圓的表面品質光滑平整同時也降低次表面損傷層深度。在自行開發的熱熔膠研磨墊方面，製作材料是使用熱熔膠熱固性高分子材料 Ethylene-Vinyl Acetate(EVA) 球型顆粒，製造流程主要透過熱熔膠塗佈機加熱使熱熔膠熔融成液態再以高壓噴霧塗佈方式使 EVA 膠液透過孔徑 0.5 mm 的膠槍形成微米級纖維絲並塗佈碳化矽磨粒(#8000)在纖維絲上；另外熱熔膠研磨墊的優點除了原料成本便宜之外還具有彈性可以緩衝研磨墊與加工物之間的作用力；最後經由研磨墊特性分析得到較佳的研磨墊為塗佈距離 20 cm 所製成的研磨墊，另外發現在纖維絲與無塵布之間存在適當熱熔膠薄層，可以產生緊密貼合的效果而不會在加工中造成研磨墊的脫落。本實驗參數設定有進給速率、研磨荷重、磨輪轉速、磨料濃度、研磨道次，晶片經過加工之後利用 SEM、AFM、TEM 、拉曼(Raman)等精密儀器觀察晶片表面及分析次表面微觀結構。在矽晶圓表面品質及次表面損傷層方面，經由實驗結果得知，在進給速率 0.5 mm/sec、研磨荷重 50 g、磨輪轉速 8000 rpm、磨料濃度 15 %、研磨道次 3 cycle 的實驗參數下，其表面粗糙度可由 Ra：41.91 nm改善到 Ra：2.45 nm、次表面損傷層厚度可降低至 150 nm，最後利用拉曼分析驗證有非晶質層(Amorphous Layer)的存在且估算厚度約10 nm。 During the silicon wafer manufacture procedure , after slicing and edge contouring , silicon wafer surface results in saw mark and damaged layer and affects the following manufacture procedure . This research tries to combine new hot-melt adhesive pad with free SiC slurry to grind silicon wafer which makes silicon wafer surface quality smooth and reduces subsurface damaged layer. In hot-melt adhesive pad aspect , the pad is made from thermosetting plastic materials(Ethylene-Vinyl Acetate) . Manufacture procedure of the hot-melt adhesive pad is to use hot-melt adhesive spray machine to heat hot-melt adhesive materials which become molten state and then use spray gun of 0.5 mm aperture to form hot-melt adhesive fiber by the high-pressured method and finally spread SiC particles(#8000) on hot-melt adhesive fiber ; the advantage of hot-melt adhesive pad , moreover , the cost of hot-melt adhesive material is cheap and it’s elastic characteristic can cushion action force between pad and silicon sample ; finally , we can select the best pad to grind silicon sample by analyzing the hot-melt adhesive pad characteristic , and we find that hot-melt adhesive pad exist a suitable hot-melt adhesive layer to let pad sustain complete shape.The experiment parameters include feed rate , load , grinding speed , SiC concentration , grinding cycle , then use precision instrument (SEM , AFM , TEM , Raman) to examine silicon sample surface and analyze subsurface microscopic structure after grinding silicon sample . In silicon wafer surface quality and subsurface damaged layer aspect , according to the experimental result , when feed rate 0.5 mm/sec , load 50 g , grinding speed 8000 rpm , SiC concentration 15% , grinding cycle 3 times , surface roughness can be improved from Ra : 41.91 nm to Ra : 2.45 nm , and then subsurface damaged layer can be improved to about 150 nm , finally the silicon sample surface exists amorphous layer by using raman spectral analysis and computes it’s thickness about 10 nm . |
