Anisotropic diamond etching through thermochemical reaction between Ni and diamond in high-temperature water vapour

Abstract

Diamond possesses excellent physical and electronic properties, and thus various applications that use diamond are under development. Additionally, the control of diamond geometry by etching technique is essential for such applications. However, conventional wet processes used for etching other materials are ineffective for diamond. Moreover, plasma processes currently employed for diamond etching are not selective, and plasma-induced damage to diamond deteriorates the device-performances. Here, we report a non-plasma etching process for single crystal diamond using thermochemical reaction between Ni and diamond in high-temperature water vapour. Diamond under Ni films was selectively etched, with no etching at other locations. A diamond-etching rate of approximately 8.7 μm/min (1000 °C) was successfully achieved. To the best of our knowledge, this rate is considerably greater than those reported so far for other diamond-etching processes, including plasma processes. The anisotropy observed for this diamond etching was considerably similar to that observed for Si etching using KOH.

The surface hybridization of diamond with vertical graphene: a new route to diamond electronics

“…3c), making the carbon atoms of diamond break their sp 3 bond and reform to sp 2 bonded graphene. Due to the stability of the (111) plane 25,26 (demonstrated in wet etching at 1000 1C), 25 the transformation can be dominated by the diamond (111) plane from the surface, resulting in its inward propagation (arrows in Fig. 3d and e) which has been observed from the transformation of diamond to graphite at 1800 1C under a vacuum.…”

Single-Step Formation of Ni Nanoparticle-Modified Graphene–Diamond Hybrid Electrodes for Electrochemical Glucose Detection

“…Meanwhile, Ni thin film would gradually aggregate into Ni NPs with various sizes due to the dewetting phenomenon at high temperature [38]. During the cooling process, the supersaturated carbon atoms in the Ni NPs would precipitate to form graphene layers through an out-diffusion process [39]. As a result, a Ni NPs-modified graphene–diamond hybrid may have a larger specific active surface area and better electrocatalytic activity for further electrochemical detection.…”

Ni-mediated reactions in nanocrystalline diamond on Si substrates: the role of the oxide barrier

“…3 In recent demonstrations of highmobility graphene-based radio frequency eld-effect transistors, instead of SiO 2 , graphene was transferred on such an NCD dielectric layer to avoid charge traps, always present in SiO 2 hampering high performance of the device. 4 However, when graphene is directly synthesized by Ni-mediated graphitization of NCD, [5][6][7][8][9] actually, the graphitic layers are formed also in the bulk between the NCD nanocrystals. 10 In such case, the quality of SiO 2 interface, as we show here, can play an important role at the electronic transport.…”