不同破裂方式於光阻薄膜引發破裂波紋受加馬射線影響之探討

Different fracture approaches to induce ripple patterns on non-irradiated and irradiated photoresist film

李玥瑩(Yueh-Ying Lee)

指導教授 ： 李三保

國立清華大學/工學院/材料科學工程學系/碩士(2012年)

摘要

在此實驗中，我們將實驗結果主要分為兩個部份來探討。第一部分， 將mrI-8030E的光阻旋於已經清理乾淨的矽基板上，而後立即覆蓋上另一片同等大小的矽基板，以形成三明治結構試片。經過加熱加壓，確保光阻層與兩片矽基板呈現緊密接合，接著使用三種不同的實驗破裂方式，來引發規則且具週期性的破裂導致微結構。然後進一步探討與比較各個破裂波紋的圖形、空間波長、振幅等。在第一個破裂實驗中，我們將施力集中在矽基板上板的一點來分開三明治試片，結果會得到以施力點為中心的半圓形波紋。而在第二個實驗中，我們將三明治試片用單軸的拉伸力使之分離，即會出現與光阻薄膜邊界呈45°(或135°)的規則直線波紋。於第三種破裂實驗中，我們採用將刀片嵌入光阻薄膜內來造成破裂的方式，形成了與刀片嵌入方向平行(或垂直)的週期性破裂波紋。
在第二部分，我們運用於被鈷60輻射後的光阻，並依上述實驗步驟，針對輻射前後的光阻和不同輻射劑量所引發的破裂波紋做膜厚，波紋波長及振幅的探討。
最後，我們利用由表面能和殘留表面應力所組成的表觀表面應力理論來解釋表面波紋的形成，並研究輻射前後的光阻在破裂過程中所引發的表觀表面應力上的差異。

關鍵字

破裂波紋 ； 加馬射線 ； 光阻

並列摘要

The experiment results are divided into two parts. Part one: the photoresist thin film is first sandwiched by two rigid Si substrates. After heating and pressing, those sandwiched specimens are separated by three kinds of approaches to induce periodic cracked ripples on both the substrate surfaces. We compared the physical parameters of those induced surface undulations, like crack pattern, ripple wavelength and amplitude, and relation between each other. The first type of separation is applied a point force at the edge of top Si plate, and the semicircular crack pattern appeared spontaneously. The second one is applyied a uniaxial tensile loading on the sandwiched specimen, and the method can induce 45°(or 135°)-stripe cracks to the edge of photoresist film. The third one is inserted a razor blade into the middle layer of sandwiched specimen (photoresist thin film), to induce fracture, then, the appeared cracked ripples are parallel (or normal) to the inserted direction of the blade.
Part two: we examine the effect of gamma-irradiation at a dose rate 5 kGy/hr on mrI-8030E photoresist and the fracture-induced structure, including film thickness, molecular weight and those geometric parameters of the crack ripple.
Finally, we used the concept of apparent surface traction consisted of surface energy and residual surface stress to explain the formation of the surface morphology. Furthermore, we investigated the difference of apparent surface tractions before and after irradiation.

參考文獻

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