Various shapes of silicon freestanding microfluidic channels and microstructures in one-step lithography
Various shapes of silicon freestanding microfluidic channels and microstructures in one-step lithography
复制标题
DOI：
10.1088/0960-1317/19/5/055003
复制
发表时间：
2009-05
影响因子：
2.3
通讯作者：
P. Pal;Kazuo Sato
中科院分区：
文献类型：
--
作者：
P. Pal;Kazuo Sato
在这项研究中，我们开发并演示了一种在一步光刻中形成各种形状的硅独立式微流控通道和微结构的制造方法。该制造工艺采用以氮化硅为中间层的硅片直接键合、硅局部氧化(LOCOS)工艺和湿法各向异性腐蚀。两种不同类型的腐蚀剂(添加非离子表面活性剂(Triton-X-100)和纯25wt%TMAH溶液)串联使用来进行硅各向异性腐蚀。添加表面活性剂的四甲基氢氧化铵(TMAH)被用来确定结构的形状，而纯TMAH由于其快速释放而被用来获得高的底切。考虑到湿法各向异性刻蚀的互补性金属氧化物半导体(CMOS)后处理问题，非离子表面活性剂是首选。在纯⟨溶液和添加表面活性剂的⟩溶液中，测量和分析了尖锐和圆形凹角处的底切，边缘沿TMAH 1 0 0方向排列。还提出了在制造所需形状和尺寸的结构时必须考虑的掩模设计问题。
In this research, we have developed and demonstrated a fabrication method for the formation of various shapes of silicon freestanding microfluidic channels and microstructures in one-step photolithography. The fabrication process utilizes the silicon direct wafer bonding with silicon nitride as an intermediate layer, local oxidation of the silicon (LOCOS) process and wet anisotropic etching. Two different types of etchants (non-ionic surfactant (Triton-X-100) added and pure 25 wt% TMAH solutions) are used in series to perform silicon anisotropic etching. Surfactant-added tetramethyl ammonium hydroxide (TMAH) is employed to define the shapes of the structures, while pure TMAH is used to get high undercutting for their fast releasing. The non-ionic surfactant is preferred considering the complementary metal-oxide semiconductor (CMOS) post process issue of wet anisotropic etching. The undercutting at sharp and rounded concave corners, edges aligned along ⟨1 0 0⟩ directions, is measured and analyzed in both pure and surfactant-added TMAH solutions. Mask design issues that must be taken into consideration for the fabrication of desired shape and size structures are also presented.