Multiple enlarged growth of single crystal diamond by MPCVD with PCD-rimless top surface  

作　　者：Ze-Yang Ren Jun Liu Kai Su Jin-Feng Zhang Jin-Cheng Zhang Sheng-Rui Xu Yue Hao 任泽阳;刘俊;苏凯;张金风;张进成;许晟瑞;郝跃(State Key Discipline Laboratory of Wide Band-Gap Semiconductor Technology, School of Microelectronics, Xidian University)

机构地区：[1]State Key Discipline Laboratory of Wide Band-Gap Semiconductor Technology,School of Microelectronics,Xidian University,Xi'an 710071,China

出　　处：《Chinese Physics B》2019年第12期352-357,共6页中国物理B（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(Grant Nos.2018YFB0406504 and 2016YFB0400105);the National Postdoctoral Program for Innovative Talents,China(Grant No.BX20190263)

摘　　要：We report the simultaneous enlarged growth of seven single crystal diamond(SCD) plates free from polycrystalline diamond(PCD) rim by using a microwave plasma chemical vapor deposition(MPCVD) system. Optical microscope and atomic force microscope(AFM) show the typical step-bunching SCD morphology at the center, edge, and corner of the samples. The most aggressively expanding sample shows a top surface area three times of that of the substrate. The effective surface expanding is attributed to the utilization of the diamond substrates with(001) side surfaces, the spacial isolation of them to allow the sample surface expanding, and the adoption of the reported pocket holder. Nearly constant temperature of the diamond surfaces is maintained during growth by only decreasing the sample height, and thus all the other growth parameters can be kept unchanged to achieve high quality SCDs. The SCDs have little stress as shown by the Raman spectra. The full width at half maximum(FWHM) data of both the Raman characteristic peak and(004) x-ray rocking curve of the samples are at the same level as those of the standard CVD SCD from Element Six Ltd. The nonuniformity of the sample thickness or growth rate is observed, and photoluminescence spectra show that the nitrogen impurity increases with increasing growth rate. It is found that the reduction of the methane ratio in the sources gas flow from 5% to 3% leads to decrease of the vertical growth rate and increase of the lateral growth rate. This is beneficial to expand the top surface and improve the thickness uniformity of the samples. At last, the convenience of the growth method transferring to massive production has also been demonstrated by the successful simultaneous enlarged growth of 14 SCD samples.We report the simultaneous enlarged growth of seven single crystal diamond(SCD) plates free from polycrystalline diamond(PCD) rim by using a microwave plasma chemical vapor deposition(MPCVD) system. Optical microscope and atomic force microscope(AFM) show the typical step-bunching SCD morphology at the center, edge, and corner of the samples. The most aggressively expanding sample shows a top surface area three times of that of the substrate. The effective surface expanding is attributed to the utilization of the diamond substrates with(001) side surfaces, the spacial isolation of them to allow the sample surface expanding, and the adoption of the reported pocket holder. Nearly constant temperature of the diamond surfaces is maintained during growth by only decreasing the sample height, and thus all the other growth parameters can be kept unchanged to achieve high quality SCDs. The SCDs have little stress as shown by the Raman spectra. The full width at half maximum(FWHM) data of both the Raman characteristic peak and(004) x-ray rocking curve of the samples are at the same level as those of the standard CVD SCD from Element Six Ltd. The nonuniformity of the sample thickness or growth rate is observed, and photoluminescence spectra show that the nitrogen impurity increases with increasing growth rate. It is found that the reduction of the methane ratio in the sources gas flow from 5% to 3% leads to decrease of the vertical growth rate and increase of the lateral growth rate. This is beneficial to expand the top surface and improve the thickness uniformity of the samples. At last, the convenience of the growth method transferring to massive production has also been demonstrated by the successful simultaneous enlarged growth of 14 SCD samples.

关 键 词：DIAMOND chemical vapour deposition crystal growth expanded top surface polycrystalline diamond rimless 

分 类 号：TG1[金属学及工艺—金属学]