| 摘要: | 本研究主要目的在發展創新石英晶圓材料之連續流式線電化學放電加工(WECDM)以及線電泳沉積拋光法。本論文分為兩大部分，第一部分為超音波輔助連續流式線電化學放電加工研究，於加工石英晶圓時，線電極與石英晶圓試片加工間隙間可形成微小加工區域且密實之絕緣氣膜結構，以創造微區域線電化學放電環境，並採用脈衝電源與超音波輔助加工，可大幅降低不穩定放電現象及減少大型放電熱能產生，避免造成加工線電極容易斷線，導致線電極大量損耗等問題，並增進加工精度及加工速度，克服石英晶圓材料難以加工之困難點。本研究係採用KOH電解液進行參數實驗，探討加工參數如加工電壓、脈衝週期、衝擊係數、進給速度及超音波振幅對加工品質特性的影響，加工品質特性包括平均槽寬及表面形貌等，由實驗結果得知，在脈衝電源以及超音波振動輔助下，於放電電壓44V、放電週期時間100µs、衝擊係數40%、進給速度5µm/s以及超音波功率6段的加工參數組合時，可得到較小線電化學放電加工後槽寬0.208mm。
第二部分為超音波輔助電泳沉積拋光石英晶圓側壁之研究，係於超音波輔助連續流式線電化學放電加工後，利用在微小區域電泳沉積披覆線電極來進行加工後之槽道側壁拋光。實驗時係使用原線電化學放電加工機之機構，在WECDM切槽後更換治具進行槽道側壁之線電泳沉積拋光，並使用鍍鋅黃銅線當作工具電極，圓筒型黃銅做為輔助電極，採用具碳化矽(SiC)磨粒之NaOH電解液進行電泳披覆，再利用電泳披覆有SiC磨粒之線電極，透過捲線機構轉動對石英切槽後之側壁進行拋光，並探討加工參數如加工電壓、磨料濃度、進給速度、拋光次數及超音波功率對石英晶圓切槽側壁拋光品質特性的影響，加工品質特性包括表面粗糙度及表面形貌等，由實驗結果得知，於工作電壓12V、磨料濃度13wt.%、進給速度10μm/s、拋光次數4次及超音波功率2段時，可得到本研究之最低表面粗糙度值0.112μmRa，表面粗糙度改善率為87.2%。
;The main purpose of this study is to develop innovative continuous flow wire electrochemical discharge machining (WECDM) and wire electrophoretic deposition polishing methods for quartz wafer materials. This thesis is divided into two major parts. The first part focuses on the research of ultrasonic vibration assisted wire electrochemical discharge machining with continuous electrolyte flow. When processing quartz wafers, a micro area with a dense insulating gas film structure can be formed between the wire electrode and the quartz workpiece to create a micro area for WECDM. Unstable discharge phenomena and excessive heat generation can be significantly reduced by using pulse power sources and ultrasonic-assisted processing, which prevents wire electrode breakage and extensive electrode wear. Furthermore, it can also improve processing accuracy and cutting speed to overcome the challenges of processing quartz wafer materials. This study employs a KOH electrolyte for parameter experiments to investigate the impact of processing parameters, such as working voltage, duration time, duty factor, feed rate and ultrasonic power on processing quality characteristics. These quality characteristics include average slot width and surface morphology. Experimental results indicate that under the influence of pulse power and ultrasonic vibration, with the following combination of processing parameters: working voltage of 44V, duration time of 100µs, duty factor of 40%, feed rate of 5µm/s, and ultrasonic power of 2 level, a smaller slot width of 0.208mm can be achieved after WECDM.
The second part involves the study of ultrasonic-assisted electrophoretic deposition for polishing the sidewalls of quartz wafers. After ultrasonic-assisted WECDM with continuous electrolyte flow, the sidewall polishing of the slots is performed by a coated electrode using electrophoretic deposition in a confined area. In this experiments, the mechanism of the original WECDM machine was used. After slicing the slot with WECDM, the fixture was replaced to perform electrophoretic deposition and polishing on the slot sidewalls. Zinc-coated brass wire was used as the tool electrode, and a cylindrical brass structure was used as the auxiliary electrode. Electrophoretic deposition was performed using a NaOH electrolyte containing silicon carbide (SiC) particles. The quartz sidewalls after cutting were polished by rotating the winding mechanism to feed the wire electrode. The study investigates the effects of processing parameters, such as working voltage, SiC particle concentration, feed rate, polishing times and ultrasonic power level on the quality characteristics of polished sidewalls in quartz wafers. The quality characteristics include surface roughness and surface morphology. Experimental results show that the lowest surface roughness value of 0.112μmRa was achieved in this study when process with a working voltage of 12V, a SiC particle concentration of 13wt.%, a feed rate of 10μm/s, 4 polishing times, and ultrasonic power level of 2-stage. The surface roughness improvement rate was 87.2%. |
