Study of corner compensating structures and fabrication of various shapes of MEMS structures in pure and surfactant added TMAH
Study of corner compensating structures and fabrication of various shapes of MEMS structures in pure and surfactant added TMAH
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DOI：
10.1016/j.sna.2008.09.002
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发表时间：
2009-09-24
影响因子：
4.6
通讯作者：
Gosalvez, Miguel A.
中科院分区：
文献类型：
--
作者：
Pal, Prem;Sato, Kazuo;Gosalvez, Miguel A.
在这项研究中，我们已经研究了各种形状的角补偿结构，如三角形，正方形以及（110）和< 100 >定向光束用于纯和表面活性剂添加四甲基氢氧化铵（TMAH）的解决方案。在有和没有少量表面活性剂NC-200（蚀刻剂总体积的0.1%）的情况下使用10%、20%和25%的蚀刻剂浓度。该表面活性剂含有100%的聚氧乙烯-烷基-苯基-醚，具有疏水性头部'CH（3）（CH（2））（8）-C（6）H（4）'和亲水性尾部'O（CH（2）CH（2）O）（20）H'。由于当添加少量表面活性剂时纯TMAH的蚀刻特性（诸如蚀刻速率、凸角底切和蚀刻各向异性）发生显著变化，因此针对纯TMAH（或KOH）提出的所有设计不能被用于添加表面活性剂的TMAH。在所有的补偿设计中，三角形的几何形状被发现是最佳的选择，表面活性剂添加25%的TMAH溶液。优化设计成功地用于演示芯片隔离和梅萨结构的弯曲V形槽包围的有限的空间是可用于补偿图案的凹槽的制造。此外，添加25% TMAH的NC-200还用于制造微流体通道、具有圆形凹凸角的微结构以及具有光滑侧壁的45 °反射镜。(C)2008 Elsevier B. V.保留所有权利。
In this research, we have studied the various shapes of corner compensation structures such as triangles, squares as well as (110) and < 100 > oriented beams for use with pure and surfactant added tetramethyl ammonium hydroxide (TMAH) solutions. The etchant concentrations of 10%, 20% and 25% were used with and without a small amount of surfactant NC-200 (0.1% of the total volume of the etchant). This surfactant contains 100% polyoxyethylene-alkyl-phenyl-ether with a hydrophobic head 'CH(3)(CH(2))(8)-C(6)H(4)' and a hydrophilic tail 'O(CH(2)CH(2)O)(20)H'. As the etching characteristics (such as etch rate, convex corner undercutting and etching anisotropy) of pure TMAH change dramatically when a small amount of surfactant is added, all the designs proposed for pure TMAH (or KOH) cannot be adopted for surfactant added TMAH. Among all the compensating designs, the triangular shaped geometry is found to be the optimal choice for the surfactant added 25% TMAH solution. The optimized design is successfully used for demonstrating the fabrication of grooves for chip isolation and mesa structures surrounded by bent V-grooves where limited space is available for the compensating pattern. Furthermore, the NC-200 added 25% TMAH was also used to fabricate microfluidic channels, microstructures with rounded concave and sharp convex corners, and a 45, mirror with smooth sidewalls. (C) 2008 Elsevier B.V. All rights reserved.