高頻微機電探針卡製程設計與製作

Design and Fabrication of RF MEMS Probe Card

鄭誥廷(Gao-Ting Cheng)

指導教授 ： 黃榮堂 ； 林震

國立臺北科技大學/機電學院/機電整合研究所/碩士(2012年)

摘要

以目前半導體製程而言，所採用基底介質普遍為矽基底，雖然台灣在此種製程作法相當成熟，但當考慮到高頻所產生的寄生效應與高頻反射現象後，其效果仍是有待改善，之後為了進一步改善結構特性，將基底介質改為對於高頻傳輸特性有明顯提升的玻璃(Glass)作為基板，在未來與Through Glass Via (TGV) 技術結合將傳輸線接至結構背面，以利後方裝置連接。
目前為止，利用微機電技術所研製的探針有些許功能上的限制如低的探針接觸力、複雜的製作過程與操作於高頻時會有非常大的傳輸損失。換句話說，一般的微機電探針卡關鍵的問題，在於每根探針無法承受或產生足夠的力量來刺穿金屬氧化層並操作於高頻段環境。而本研究預計製作可應用於高頻傳輸的微機電探針，一開始利用模擬軟體Ansoft HFSS與Ansys Workbench得到其S11> -20dB、S12 > -1dB與模擬探針結構之應力、剪力及位移量，結構模擬完成後開始製造探針模穴，並以電鑄的方式沉積鎳使探針懸臂厚度增加來加強支撐懸臂的強度，之後利用研磨製程提升探針整體共面度，再與玻璃基板連接，藉由Lift-off技術釋放探針結構，並於最外層無電解電鍍上一層金，改善高頻傳輸時所產生的肌膚效應，以成功的製作出一體成型之微探針結構。
該探針結構設計為GSG形式，結構設計過程需要四道光罩相互對準，S端探針寬度50μm，G端探針寬度屬漸進式從400μm縮至50μm，間距為150μm，探針總長度為1900μm。

關鍵字

高頻 ； 探針卡 ； 微機電 ； 玻璃

並列摘要

For the recent development of Semiconductor process, the base substrate in general is the silicon. Although the silicon process is quite mature in Taiwan but the high frequency parasitic effects and reflection phenomenon of silicon still needs to be improved. In order to improve the characteristics of silicon structure, we change the substrate to glass because it has significant high frequency transmission characteristics. In the future, with Through Glass Via (TGV) technology, the probe on the front side of the glass substrate can be connected to the transmission line on the back, and further facilitate the connection to the other electronic devices.
The probe fabricated by MEMS technology has some functional limitations such as low probe contact force, complex production process and very large transmission loss when operate at high frequency. In other words, the main issue of MEMS probe card is that each probe can’t bear or generate enough forces to puncture the metal oxide layer and operating at the high frequency environment. In this research, we fabricated MEMS probe to apply for high frequency transmission. First we used the simulation software Ansoft HFSS/Ansys Workbench to simulate the probe in terms of S-parameter S11> -20dB, S12 > -1dB, structure stress, shear force and deflection. After finishing the structural simulation, we started to manufacture the probe cavity and electro-formed nickel. The purpose is to increase thickness of Probe cantilever to enhance its strength and used the polishing process to make the thickness of the probe uniform. After polishing the wafer, we used the Lift off technology to separate probe from cavity. Finally, we coat the gold around the probe in order to reduce the skin effect.
The probe structure design for the GSG type requires four masks aligned with each other under conditions as following: width of the S-end is 50μm, the end of the G width is progressive from 400μm reduced to 50μm, probe pitch is 150μm, and the length of the probe is 1900μm.

並列關鍵字

RF ； Probe Card ； MEMS ； Glass

參考文獻

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