Deep reactive-ion etching

About: Deep reactive-ion etching is a research topic. Over the lifetime, 2113 publications have been published within this topic receiving 35932 citations.

Advanced silicon etching using high-density plasmas

Abstract: High density plasmas are beginning to dominate the market for advanced anisotropic silicon etching for MEMS applications. This paper looks at the reasons behind this dominance for high etch rate, deep anisotropic etching. A discussion of anisotropic etch mechanisms highlights the need for sidewall passivation to meet these requirements. Results are presented of a novel room temperature advanced silicon etch process: >= 2 micrometers /min; >= 70:1 selectivity to resist (and >= 150:1 to oxide); up to 30:1 aspect ratio; 500 micrometers depth capability; using a non-toxic, non-corrosive environmentally acceptable fluorine-based chemistry.

SU-8 as a structural material for labs-on-chips and microelectromechanical systems.

Abstract: Since its introduction in the nineties, the negative resist SU-8 has been increasingly used in micro- and nanotechnologies. SU-8 has made the fabrication of high-aspect ratio structures accessible to labs with no high-end facilities such as X-ray lithography systems or deep reactive ion etching systems. These low-cost techniques have been applied not only in the fabrication of metallic parts or molds, but also in numerous other micromachining processes. Its ease of use has made SU-8 to be used in many applications, even when high-aspect ratios are not required. Beyond these pattern transfer applications, SU-8 has been used directly as a structural material for microelectromechanical systems and microfluidics due to its properties such as its excellent chemical resistance or the low Young modulus. In contrast to conventional resists, which are used temporally, SU-8 has been used as a permanent building material to fabricate microcomponents such as cantilevers, membranes, and microchannels. SU-8-based techniques have led to new low-temperature processes suitable for the fabrication of a wide range of objects, from the single component to the complete lab-on-chip. First, this article aims to review the different techniques and provides guidelines to the use of SU-8 as a structural material. Second, practical examples from our respective labs are presented.

Novel interconnection technologies for integrated microfluidic systems

Abstract: A new approach to realize silicon based integrated microfluidic systems is presented By using a combination of silicon fusion bonding (SFB) and deep reactive ion etching (DRIE), multi-level fluidic `circuit boards' are fabricated and used to integrate microfluidic components into hybrid systems A multi-level laminating mixer and a manifold with multiple pressure sensors are presented as application examples To interface the microfluidic system to the macroscopic world, three types of DRIE-fabricated, tight-fitting fluidic couplers for standard capillary tubes are described One type of coupler is designed for minimal dead space, while another type reduces the risk of blocking capillaries with adhesive A third design demonstrates for the first time a silicon/plastic coupler combining DRIE coupler technology with injection-molded press fittings

Deep reactive ion etching of Pyrex glass using SF6 plasma

Abstract: Deep reactive ion etching of Pyrex glass has been characterized in sulfur hexafluoride plasma (SF6). High etch rate (∼0.6 μm/min) was demonstrated under a condition of low pressure (0.2 Pa) and high self-bias (−390 V) by using a magnetically enhanced inductively coupled plasma reactive ion etching. Vertical etch profile (taper angle ∼88°), high aspect ratio (>10) and through-wafer etching of Pyrex glass (200 μm in thickness) were achieved under the condition by using thick (20 μm) and vertical electroplated nickel film as mask. The vertical etch profile was achieved when the mask opening is narrower than 20 μm because the deposition of nonvolatile product on the sidewall is reduced. A novel etching technique “scoop-out etching” was demonstrated by using the present etching characteristics.

Wafer-scale patterning of sub-40 nm diameter and high aspect ratio (>50:1) silicon pillar arrays by nanoimprint and etching

Abstract: We demonstrate wide-area fabrication of sub-40 nm diameter, 1.5 µm tall, high aspect ratio silicon pillar arrays with straight sidewalls by combining nanoimprint lithography (NIL) and deep reactive ion etching (DRIE). Imprint molds were used to pre-pattern nanopillar positions precisely on a 200 nm square lattice with long range order. The conventional DRIE etching process was modified and optimized with reduced cycle times and gas flows to achieve vertical sidewalls; with such techniques the pillar sidewall roughness can be reduced below 8 nm (peak-to-peak). In some cases, sub-50 nm diameter pillars, 3 µm tall, were fabricated to achieve aspect ratios greater than 60:1.