微機電製作快速加熱模具於晶圓級微射出成形之應用

MEMS Fabricated Rapid Heating Mold for Wafer-Level Injection Micromolding

指導教授 : 黃榮堂    研究生 : 何侑倫  製造科技研究所 91年


摘要

  本文旨在設計與製作一快速加熱模具,其主要特徵包括以一連貫的微機電與UV-LIGA製程技術,將微加熱器與溫度偵測器直接製作於模仁之背後,由於微加熱器提供模仁微結構微區局部的高溫,因此當塑料流經模仁微結構時,得以獲得良好的流動性並得到較完整的複製性,依本文之設計概念配合射出壓縮成形模具,最後以完成晶圓級微射出成形之目的。此快速加熱模具設計概念經ANSYS熱傳分析後顯示,微加熱器確實可以提供模仁局部的熱源,而且加熱效率較傳統電熱器加熱方式快上許多,約在20秒內可將模仁局部升溫至150℃以上。本文同時以微機電矽基製程與JSR THB系列負型厚膜光阻等不同方式,完成製作微結構電鑄鎳模仁,另外選擇白金(Pt)為主要材料,並同時以Lift-off方式製作微加熱器(Microheaters)與溫度偵測器(RTD)等元件,微加熱器透過不同阻值的設計經適當的功率調整後即可快速達到較高模溫所需之溫度(120-150℃),而溫度偵測器在工作溫度範圍內,其溫度與電阻的關係也近乎線性。而本文在最後以一模擬實際加熱情況之實驗來測量微結構模仁的加熱效率,經結果數據發現如此快速加熱模具之設計確實可獲得快速的模具升溫。

ABSTRACT

  This thesis is aim to design and fabricate a rapid heating mold which mainly provide a function of solving the poor replication for wafer-level injection micromolding. The rapid heating apparatus is composed of a metal or silicon mold-insert, microheaters and temperature sensing elements(RTD). Those elements are reasonably fit with the mold-insert utilizing well-defined MEMS and UV-LIGA process. The microheaters are employed to apply the local heat for microstructures of mold-insert during the molding process, and RTD are used for measuring the actual temperature of the electroplated mold-insert. The concept has successfully verified with finite element method, and the microheaters really provide a better efficiency for mold heating than conventional bar-type electric heaters. In terms of fabrication, two main methods, si-based dry etching and thick photoresist (PR), are used for fabricating the mold-insert with microstructures and the Platinum (Pt) is employed as the material of microheaters and RTD. The microheaters serve as the heating sources satisfied with the need of mold temperature, and the RTD element also provides a nearly linear over a range of the mold temperature. Finally, we set a simple experiment for realizing the heating efficient of Ni mold-insert and it really exhibits a good result.