Nucleation and Selective Deposition of Diamond Thin Films

Abstract

Diamond has great potential for electronic, optical, mechanical, chemical, and nuclear applications due to its superior properties. However, natural diamond is rare and expensive, being a metastable phase at normal pressure and temperature. The diamond synthesis at high temperatures and high pressures (HTHP), where diamond is a stable phase [l], was a breakthrough for large scale industrial applications. However, synthetic diamond is used mainly in abrasive and cutting tools industries [2], the crystals obtained by the HTHP method being too small and expensive for many applications in optics, electronics, or other industries [3].Polycrystalline as well as single-crystal films of diamond on single-crystal diamond substrates were first obtained in the seventies by the Russian team of Spitsyn, Bouilov, Derjaguin, and coworkers [4 to 101 by the gas chemical transport reaction (CTR) method. Crystals of several micrometers in size and polycrystalline films, grown on various foreign substrates (Cu, Au, Si, W, Mo), were reported by the same team [8].

Studies on nucleation process in diamond CVD: an overview of recent developments

“…Diamond nucleation on non-diamond surfaces can be enhanced by the surface pretreatments, with ultrasonic-scratching and biasing having the best efficacy on nucleation enhancement, followed by scratching, seeding, covering/coating, and ion implantation, etc., as summarized in Table 5. Nucleation on pretreated surfaces is observed to occur primarily on carbon-rich particles or defects, such as scratches, grain boundaries, particle boundaries, dislocations, electron bombardment damages, and edges of etch pits/craters [39,72,75,79]. Pulsed laser irradiation + coating a-C, WC, cBN layer enhancement [106] Carburization enhancement [31,70] As schematically depicted in Figure 4 [72], nucleation enhancement by scratching is attributed to (a) seeding effect [78,98,107], (b) minimization of interfacial energy on sharp convex surfaces [20,108], (c) breaking of a number of surface bonds or presence of a number of dangling bonds at sharp edges [100], (d) strain field effects [105], (e) rapid carbon saturation (fast carbide formation) at sharp edges [72,109], and (f) removal of surface oxides [39,100].…”

“…Surface nucleation densities and rates on non-diamond substrates vary from 10 3 to 10 11 cm -2 [24,39,40,41,[74][75][76][77][78], and from 10 3 to 10 8 cm -2 h -1 [79] (10 9 to 10 10 cm -2 h -1 , as estimated from the measured data in [40]), respectively, depending on substrate materials, surface pretreatment methods, and synthesis conditions.…”

Diamond Nucleation from Activated Vapor Phase

“…Good early reviews on nucleation and selective growth of diamond films have been presented in [15]. Today it is generally accepted that the nucleation and the following DF formation on carbide-forming substrates proceeds through six stages (Figure 2).…”

Patterned diamond particle films

“…Area selective diamond growth has been reported in the literature [3][4][5][6][7][8][9][10][11] as the practical alternative to removing undesired parts of a CVD diamond film by mechanical cutting or chemical means. The methods for patterning diamond films onto nondiamond substrates that have been reported in the literature [3][4][5][6][7][8][9][10][11] generally require a series of surface pretreatment steps involving, at some point, the use of a photoresist or a silk-screen mask.…”