以飛秒雷射製作氮化鋁基板微通孔之研究

Abstract

陶瓷材料的高熱傳導率和高電阻率使其成為三維積體電路中理想的中介層材料，但目前半導體產業用於製造矽通孔的蝕刻製程不適用於陶瓷材料上，而且由於陶瓷材料的高硬度，也不容易以微機械加工的方式在陶瓷材料上製作微通孔。飛秒雷射的極高尖峰功率特性，使其可對大多數的材料加工，而且不產生熱效應，故本論文利用飛秒雷射在氮化鋁基板上產生微通孔，研究不同雷射參數，如功率、偏振態、光斑大小、聚焦角度與位置，對微通孔結構的影響。結果顯示以10物鏡，光圈孔徑0.4 cm，雷射功率125 mW，鑽孔時間1 s，聚焦深度50 μm的圓偏光對氮化鋁基板進行鑽孔，能得到孔徑約10 μm，錐度約0.03 %的微通孔。

The ceramics with high thermal conductivity and high electrical resistivity are ideal interposer materials for three-dimensional integrated circuits. However, the current etching process utilized in the semiconductor industry for fabricating through silicon via cannot be applied to ceramic materials. In addition, because of the hardness, the microvias are difficultly fabricated by the traditional micromachining processes. Fortunately, the femtosecond laser pulses with high peak power are able to be applied to most materials without thermal effect. In this thesis, the femtosecond laser pulses with various parameters, such as average power, polarization, spot size, converging angle and focus position, are utilized to produce microvias on aluminum nitride substrates. The experimental results show that the microvias on an aluminum nitride substrate with an optimal diameter of approximately 10 μm and a taper of approximately 0.03 % can be reached through a 10 objective lens, a 0.4-cm iris aperture, 50-μm focusing depth, 1-s exposure time, and the femtosecond laser pulses with 125-mW output power and circular polarization.