Legrain Antoine, Berenschot Erwin J W, Tas Niels R, Abelmann Leon
MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands.
MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands; KIST Europe, Saarbrücken, Germany.
PLoS One. 2015 May 19;10(5):e0125891. doi: 10.1371/journal.pone.0125891. eCollection 2015.
We show elasto-capillary folding of silicon nitride objects with accurate folding angles between flaps of (70.6 ± 0.1)° and demonstrate the feasibility of such accurate micro-assembly with a final folding angle of 90°. The folding angle is defined by stop-programmable hinges that are fabricated starting from silicon molds employing accurate three-dimensional corner lithography. This nano-patterning method exploits the conformal deposition and the subsequent timed isotropic etching of a thin film in a 3D shaped silicon template. The technique leaves a residue of the thin film in sharp concave corners which can be used as an inversion mask in subsequent steps. Hinges designed to stop the folding at 70.6° were fabricated batchwise by machining the V-grooves obtained by KOH etching in (110) silicon wafers; 90° stop-programmable hinges were obtained starting from silicon molds obtained by dry etching on (100) wafers. The presented technique has potential to achieve any folding angle and opens a new route towards creating structures with increased complexity, which will ultimately lead to a novel method for device fabrication.
我们展示了氮化硅物体的弹性毛细管折叠，其折翼之间的精确折叠角度为(70.6±0.1)°，并证明了这种精确微组装最终折叠角度为90°的可行性。折叠角度由可停止编程的铰链定义，这些铰链是从采用精确三维角光刻技术的硅模具开始制造的。这种纳米图案化方法利用了在三维形状的硅模板中薄膜的共形沉积和随后的定时各向同性蚀刻。该技术在尖锐的凹角处留下薄膜残留物，可在后续步骤中用作反转掩膜。通过加工在(110)硅片中通过KOH蚀刻获得的V形槽，批量制造了设计用于在70.6°停止折叠的铰链；从通过在(100)硅片上进行干法蚀刻获得的硅模具开始，获得了90°可停止编程的铰链。所提出的技术有潜力实现任何折叠角度，并为创建更复杂的结构开辟了一条新途径，这最终将导致一种新颖的器件制造方法。
