Surface Morphology of the Interface Junction of CVD Mosaic Single-Crystal Diamond

Abstract

The diamond mosaic grown on the single-crystal diamond substrates by the microwave plasma chemical vapor deposition (MPCVD) method has been studied. The average growth rate was about 16–17 μm/h during 48 hours’ growth. The surface morphologies of the as-grown diamond layer were observed. It was found that the step flow was able to move across the substrates and cover the junction interface. Raman spectroscopic mapping in the central area of the junction revealed the high stress region movement across the junction interface from one substrate to the other for about 200–400 μm. High-resolution X-ray diffractometry (HRXRD) results proved that the surface step flow movement direction had nothing to do with the off-axis directions of the original substrates. It was found that the surface height difference of substrate was the main driving force for the step flow movement, junction combination and surface morphology changing. The mechanism of the mosaic interface junction combination and step flow transformation on the mosaic surface was proposed.

Diamonds in the Current: Navigating Challenges for the Integration of Diamond in Power Electronics

“…The result is 10-12 mm crystals, but unfortunately with too many defects; [41] b) Paving or mosaic. [42][43][44] This technique involves placing substrates close to each other in an attempt to join them by means of CVD growth recovery. Mosaic wafers measuring ½ inch are currently on the market, but still have a high dislocation density, particularly at the junctions.…”

Coessential-connection by microwave plasma chemical vapor deposition: a common process towards wafer scale single crystal diamond

“…Tallaire et al [53] prepared the mosaic diamond with 7 pieces, with the observation of polycrystallined junction with a strong fluorescence of blue light under UV emission, indicating the presence of stress and cracks at the interconnection. Raman spectrum scans crossing the junction revealed a broadening of the diamond peak and shift of its position that indicated a deterioration of the crystal structure around the junction [54][55][56]. Muchnikov et al [54] studied a mosaic diamond plate with four interfaces, with comprehensive measurements using Raman mapping for stress and defect distributions, X-ray diffraction and rocking curve for orientations, and secondary ion mass spectrometry (SIMS) for impurity content evaluation.…”

“…Muchnikov et al [54] studied a mosaic diamond plate with four interfaces, with comprehensive measurements using Raman mapping for stress and defect distributions, X-ray diffraction and rocking curve for orientations, and secondary ion mass spectrometry (SIMS) for impurity content evaluation. Wang et al [55] carried out a similar research, with more attention to surface morphology on the substrates and within junction. Shu et al [56] used Raman mapping on cross section of mosaic junction, from substrate to the top surface to trace the evolution of defective zone adjacent to the junction along with the deposition.…”

Surface Morphology and Microstructure Evolution of Single Crystal Diamond during Different Homoepitaxial Growth Stages

“…However, the dislocations [11][12][13][14] and stress [15,16] in diamond films are still a major issue in developing large and high-quality diamonds. In order to improve these phenomena, several techniques have been used [17][18][19][20][21][22][23][24]. The remarkable functional properties of diamonds depend not only on their physical and chemical properties but also on their surface morphology.…”