追求輕、薄、短、小的軟性電子元件近來備受矚目，價格便宜、質輕並可撓的高分子材料不遑多讓為其基材之首選。微奈米壓印技術不受光學繞射限制，非但降低設備成本，更大幅提升精微圖案的翻製速率、提高產率，結合連續滾輪設備又將翻製速度推上極致，如何快速、準確、精良地在塑膠基材上進行圖案轉移為當務之急，基於塑膠不耐高溫的材料本質，使現行的熱壓印製程大為受限。於塑膠基材上定義精微金屬圖案以利後續建構元件是軟性電子元件另一重點，半導體製程中普遍施用的黃光微影含有危害塑膠基材的顯影液，因此在摒棄黃光製程後，如何進行金屬圖形定義為其挑戰。

本研究以自製滾輪壓印機台控制阻劑厚度、壓印溫度、滾輪轉速、溶劑量進行溶劑輔助滾輪壓印，在商用PET塑膠基材上以低溫進行稜鏡片(prism sheet)微圖案快速翻製之研究；更以溶劑輔助金屬轉印法於塑膠基材上定義微米級金屬圖形。

在溶劑輔助滾輪壓印部分，PMMA高分子不足的厚度及使PMMA高分子軟化不足、缺少流動性的過低溫度，兩者皆會在壓印過程中造成的聚二甲基矽氧烷(Polydimethylsiloxane，簡稱PDMS)軟性模具壓縮變形，使最終複製的稜鏡片微圖形失真，過快的滾輪轉速產生過大的剪切力造成PDMS模具變形而使圖形複製失敗，過量或過少的溶劑將會使圖形再破壞或複製不完整。以大於25 μm充足的阻劑厚度及36 wt%乙醇溶劑含量，能以100~110 ℃遠低於一般熱壓印操作溫度(130~205 ℃)，進行轉速為7.5~8.5 mm．s-1的滾輪壓印，成功在PET基板上完整複製週期為50 μm、高度為25 μm、面積大小為2.5 cm x 3.5 cm的稜鏡片。

溶劑輔助金屬轉印部份，在PDMS軟性模具上沉積金膜，無需進入真空設備，即能藉由PET上旋佈的PMMA黏著層在低溫(60 ℃)條件下成功轉印線寬/線距為2.5 μm/10 μm週期為12.5 μm或4 μm/4 μm週期為8 μm的方形金屬圖形達2 cm x 2 cm面積大小，其片電阻值為7.3 Ω/□。最後更在紙質基材上利用溶劑輔助金屬轉印成功製作線寬/線距為20 μm/20 μm面積達1 cm x 1 cm的金屬圖案。

As the flexible electronics devices arise more and more attention, plastic substrates become popular due to their excellent flexibility, light weight, and low cost. The patterning of fine metal decals on flexible substrate allow the realization of many applications such as OLED, organic solar cell, OFET. How to fabricate and transfer pattern onto the plastic substrate not only precisely but also rapidly is one kind of tough topic. Additionally, the plastic and polymer substances are not high temperature endurable intrinsically. Moreover, the developer used in photolithography is often harmful to organic polymer. In short, for the plastic substrate, it is a challenge to replicate patterns in a low operating temperature and to define fine metal patterns without using aqueous chemicals which do severe harm to organic materials.

We do not only a detail research about the topic of Solvent-Assisted Roller Imprinting Lithography (SA-RIL) to replicate prism sheet by using a homemade roller imprinting machine but also study another topic about Solvent-Assisted Metal Transfer Printing (SA-MTP) both on commercial plastic substrate, PET, at a low operating temperature.

We can fabricate a prism sheet with a period of 50 μm, a height of 25 μm, and a total area of 2.5 cm x 3.5 cm onto plastic substrate at a temperate of 100~110 ℃, and a roller speed of 7.5~8.5 mm．s-1 by SA-RIL. We also transfer fine metal patterns onto PET substrate, the area is 2 cm x 2 cm with a line width of 2.5 μm, a space width of 10 μm, a period of 12.5 μm, or a line width of 4 μm, a space width of 4μm, a period of 8 μm at a low temperature of 60 ℃ by SA-MTP. Finally, we carry out SA-MTP process onto conventional paper and the area of 1 cm x 1 cm with a L/S of 20 μm/20 μm.

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