High aspect ratio plasma etching of bulk lead zirconate titanate
High aspect ratio plasma etching of bulk lead zirconate titanate
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大块锆钛酸铅的高深宽比等离子蚀刻
DOI：
10.1117/12.657751
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
S. Tadigadapa
中科院分区：
文献类型：
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作者：
Srimath S. Subasinghe;A. Goyal;S. Tadigadapa
锆钛酸铅（PZT）是一种高能量密度的活性材料，具有良好的压电系数和机电耦合常数，非常适合微系统应用。在本文中，我们提出了一种快速各向异性的高深宽比蚀刻工艺，用于定义PZT微米尺寸的功能。我们使用了电感耦合等离子体反应离子蚀刻（ICP-RIE）系统，采用六氟化硫（SF6）和氩气（Ar）为基础的化学。将Au/Cr的种子层光刻图案化到精细研磨完成的PZT-4衬底上，然后在种子层上电沉积2-5 μm厚的镍，其在蚀刻过程中充当硬掩模。所展示的技术被用来蚀刻散装PZT陶瓷基板，从而打开散装PZT基板和结构集成到微系统的可能性。当ICP功率为2000 W，衬底功率为475 W，SF6气体为5 sccm，Ar气体为50 sccm时，PZT-4的最大刻蚀速率为19 μm/hr，PZT-5A的最大刻蚀速率为25 μm/hr。我们还展示了在3 μm特征尺寸上的高纵横比蚀刻（>5：1）。本文还详细分析了ICP功率、衬底功率、刻蚀气体成分对PZT刻蚀速率的影响。
Lead Zirconate Titanate (PZT) is a high energy density active material with good piezoelectric coefficient and electromechanical coupling constant making it highly suitable for microsystems applications. In this paper, we present a rapid anisotropic high aspect ratio etching process for defining micron size features in PZT. We used an inductively coupled plasma reactive ion etching (ICP-RIE) system employing sulfur hexafluoride (SF6) and argon (Ar) based chemistry. A seed layer of Au/Cr was lithographically patterned onto fine lap finished PZT-4 substrates followed by electrodeposition of a thick 2-5 μm nickel on the seed layer, which acts as a hard mask during the etching process. The demonstrated technique was used to etch bulk PZT ceramic substrates, thereby opening possibilities for integration of bulk PZT substrates and structures into microsystems. A maximum etch rate of 19 μm/hr on PZT-4 and 25 μm/hr for PZT-5A compositions was obtained using 2000 W of ICP power, 475 W of substrate power, 5 sccm of SF6, and 50 sccm of Ar on PZT substrate. We have also demonstrated a high aspect ratio etch (>5:1) on a 3 μm feature size. Detailed analysis of the effects of ICP power, substrate power, and the etch gas composition on the etch rate of PZT are also presented in this article.