Challier Michel, Sonusen Selda, Barfuss Arne, Rohner Dominik, Riedel Daniel, Koelbl Johannes, Ganzhorn Marc, Appel Patrick, Maletinsky Patrick, Neu Elke
Fachrichtung Physik, Universität des Saarlandes, 66123 Saarbrücken, Germany.
Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.
Micromachines (Basel). 2018 Mar 25;9(4):148. doi: 10.3390/mi9040148.
Many promising applications of single crystal diamond and its color centers as sensor platform and in photonics require free-standing membranes with a thickness ranging from several micrometers to the few 100 nm range. In this work, we present an approach to conveniently fabricate such thin membranes with up to about one millimeter in size. We use commercially available diamond plates (thickness 50 μ m) in an inductively coupled reactive ion etching process which is based on argon, oxygen and SF 6 . We thus avoid using toxic, corrosive feed gases and add an alternative to previously presented recipes involving chlorine-based etching steps. Our membranes are smooth (RMS roughness <1 nm) and show moderate thickness variation (central part: <1 μ m over ≈200 × 200 μ m 2 ). Due to an improved etch mask geometry, our membranes stay reliably attached to the diamond plate in our chlorine-based as well as SF 6 -based processes. Our results thus open the route towards higher reliability in diamond device fabrication and up-scaling.
单晶金刚石及其色心作为传感器平台以及在光子学领域的许多有前景的应用都需要厚度在几微米到几百纳米范围内的独立式薄膜。在这项工作中，我们提出了一种方便地制造尺寸达约一毫米的此类薄膜的方法。我们在基于氩气、氧气和六氟化硫的电感耦合反应离子蚀刻工艺中使用市售的金刚石板（厚度50μm）。因此，我们避免使用有毒、腐蚀性的进料气体，并为先前提出的涉及氯基蚀刻步骤的方法提供了一种替代方案。我们的薄膜很光滑（均方根粗糙度<1nm），并且显示出适度的厚度变化（中心部分：在约200×200μm²范围内<1μm）。由于蚀刻掩模几何形状的改进，我们的薄膜在基于氯的工艺以及基于六氟化硫的工艺中都能可靠地附着在金刚石板上。因此，我们的结果为提高金刚石器件制造的可靠性和扩大规模开辟了道路。
