SOI基板上利用簡單下壓方式組裝之微光學讀取頭

Abstract

近年來在半導體產業的發展之下，微機電製程技術有許多重大的發展。對於光學資料儲存系統而言，微光機電技術(Micro Optical Electro Mechanical System)正是提供製造更小更輕的光學資料儲存系統的一個好方法。 我們的目標是要製作一微光學資訊平台，此微光學平台是以數個三維斜面結構以及其他組裝於此平台上的光學元件所組成，因此採用應力幾乎為零且結構較厚的SOI (Silicon On Insulator)基板製作微鏡面，避免一般利用多晶矽製作時可能發生的翹曲現象。 本實驗室之前已提出利用下壓動作即可成功組裝45°微鏡面的設計，本論文將利用此下壓組裝方法，組裝4種不同角度的斜面鏡以證實此方法可用於任意角度的斜面鏡組裝，符合未來在光學平台應用中不同角度三維微結構的需求。本論文亦對於原始45°結構的誤差問題加以探討並提出改善方式，使得角度從45.9 ± 0.2° 改善為45.4 ± 0.2°。最後，本論文並且提出且成功製造出135° 三維微結構，平均角度為135.6 ± 0.2°，可應用在本論文中提出的光學讀取頭架構。此光學讀取頭的模擬結果以及設計原理在論文中有詳細的說明，是利用全像光學元件(HOE)來達到像散以及分光的功用，取代傳統光學讀取頭中利用體積較大的柱面鏡以及分光鏡，進而達到微型化的目的。此全像光學元件(HOE)以微機電製程的方法製造於光學平台的斜面結構上，它的表面輪廓以及光學特性在論文中都已經過實驗量測並驗證。完整的光學平台架構正處於製程的最後階段。

Recently, the Micro Electro Mechanical Systems (MEMS) technology has many important developments with the rapid progress in the semiconductor industry. The requirement of miniaturization and lightness pushes the development of smaller and lighter optical data storage systems. Micro optical pickup head fabricated by Micro-Opto-Electro-Mechanical System (MOEMS) technology is one of the methods to realize portable high-capacity optical storage systems. In this thesis, micro optical pickup head on an micro optical bench is composed of nonvertical micro mirrors and other optical components bonded on the optical bench. Silicon on insulator (SOI) wafers with almost zero stress are used to avoid stress-induced curvature for optical applications. In our previous study, 45° structures were assembled using a novel simple push operation. Micromirrors with four different angles were pushed up by probes to demonstrate the assembly method for arbitrary angles in this thesis. The angular deviation of the 45° structures was studied with different width of the support arms. The angles of 45° structures were improved from 45.9°±0.2° to 45.4°±0.2°. The design and assembly of 135° mirrors were verified and used in the proposed optical pickup head of this thesis. The devices were fabricated with an average angle of 135.6°± 0.2°. The simulation results and the design principle of the MEMS-based optical pickup head are present. A holographic optical element is used in the optical bench and fabricated on the nonvertical mirror. The surface profile and optical properties of the fabricated holographic were measured. The fabrication of the optical bench is in progress.