Exposure of Tantalum Carbide, Silicon Nitride and Aluminum Nitride to Chlorine Trifluoride Gas

et al. 2019

Self Cite

The high-temperature cleaning of a silicon carbide chemical vapor deposition reactor was developed using chlorine trifluoride gas and purified pyrolytic carbon (PyC) as the susceptor coating material. The purified PyC could be exposed to the chlorine trifluoride gas without causing serious damage at temperatures up to 570°C, which was in the range providing a sufficiently high silicon carbide etching rate. The spontaneous temperature increase at the susceptor surface due to the exothermic reaction heat was moderated by means of adding nitrogen gas. Thus, the particle-type silicon carbide layer could be cleaned while preventing peeling of the purified PyC surface and obtaining a practical etching rate. Additionally, the peeled surface of the purified PyC could be recovered by annealing at 900°C in ambient nitrogen containing oxygen.

Section: Methodsmentioning

confidence: 99%

High-Temperature Reactor Cleaning Using Chlorine Trifluoride Gas for Silicon Carbide Chemical Vapor Deposition

Kurashima

Hayashi

et al. 2019

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“…4,22 Such corrosion can be further avoided by using a yttrium oxide coating film. 23 The rubber gasket made of a fluorocarbon, such as Viton ® , is safely used for the 1% chlorine trifluoride gas, in addition to the highly anticorrosive rubber gasket, such as Kalrez ® , which is necessary for the 100% condition. Thus, the overall chlorine trifluoride gas lower than 1% has various practical advantages, while the total Figure 7.…”

Section: Resultsmentioning

confidence: 99%

Lowest Concentration of Chlorine Trifluoride Gas for Cleaning Silicon Carbide Chemical Vapor Deposition Reactor

Takizawa

Hayashi

et al. 2022

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A dilute chlorine trifluoride gas at less than 1% was possible for the cleaning of a silicon carbide chemical vapor deposition (CVD) reactor. For 20 minutes, the chlorine trifluoride gas at the concentrations of 0.5 - 1 % in ambient nitrogen at atmospheric pressure could detach the 30-m-thick particle-type polycrystalline silicon carbide CVD film from the susceptor which had a coating film made of a purified pyrolytic carbon (PPyC). While the PPyC film had some damage due to the shallow fluorine diffusion, it could be recovered without any pit formation by annealing in ambient nitrogen containing a trace amount of oxygen at atmospheric pressure for 10 minutes at the temperature of 845°C.

“…After exposure to the ClF 3 gas, the Si-N is changed into the volatile species of SiF 4 and N 2 . 4 Thus, the position where the Si-N existed may become a shallow void to slightly change the surface morphology. Simultaneously, the C-C and C-O react to form C-F (Group II).…”

Section: Resultsmentioning

confidence: 99%

“…One of the effective ways is an anticorrosive coating which can be produced by thin films made of SiC, SiN, SiO 2 , SiON, SiCNO, etc. [1][2][3][4][5] Because a SiCNO material is expected to have properties consisting of the mixed advantages of SiC, SiN and SiO 2 , the SiCNO film was produced by a plasma-enhanced chemical vapor deposition (PECVD). [6][7][8][9][10] In a previous study 10 for evaluating the anticorrosive nature of the SiCNO film, a significantly strong etchant, such as ClF 3 gas at 100% and at atmospheric pressure, was used.…”

mentioning

confidence: 99%

Chemical Conditions of SiCNO Film Exposed to ClF₃ Gas

Hori

Kawakami

2021

Self Cite

A SiCNO film containing 28% nitrogen was formed by plasma-enhanced chemical vapor deposition with no heating assistance using SiH 3 CH 3 , N 2 and Ar gases. The 15 nm thick layer of the film was then etched off utilizing 10% ClF 3 gas at room temperature for 1 min. After etching, the fluorine and chlorine concentrations within the film did not increase but they became higher at the surface. The removal rate of Si-N component was considered to be faster than that of Si-C, Si-O and C-N components, based on the X-ray photoelectron spectroscopy results. Overall, the etching was considered to occur following the etching behavior of the components formed between four elements, that is, Si, C, N, and O.