Role of xenon additive in microwave plasma-assisted (H2+CH4) chemical vapor deposition of diamond thin film

Hosomi, Takeshi; Maki, Tetsuro; Kobayashi, Takeshi; Yoshizako, Yuji; Taniguchi, Michio; Sugiyo, Masato

doi:10.1063/1.368916

Cited by 9 publications

(5 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…About 50% increase in growth rate was observed in the presence of 1%Xe in the CH 4 and H 2 precursors using an MPCVD process. 167 A morphological change from the cubic to platelet grain structure was observed without degradation of the crystallinity. The favourable effects of Xe addition were attributed to its low dissociation and excitation energies (8 .…”

Section: R~imentioning

confidence: 93%

“…[156][157][158][159] The presence of an additive such as H 2 , N 2 , F 2 , Ar, Xe, H 2 S and PH 3 in the precursor gas also affected the diamond growth. [160][161][162][163][164][165][166][167][168][169] The enhanced nucleation and growth of diamond film was achieved by introducing CH 4 right from the beginning instead of introducing it after 5 min, at substrate temperature T S .700uC using the RF and HFCVD methods. 159 The film obtained was very smooth and the contamination from W filament was reduced to a large extent by preheating the filament in CH 4 and H 2 atmosphere and placing it close to the upper electrode.…”

Section: Effect Of Variation In Processing Conditions and Additives I...mentioning

confidence: 99%

See 1 more Smart Citation

A review of nucleation, growth and low temperature synthesis of diamond thin films

Das¹,

Singh²

2007

International Materials Reviews

149

View full text Add to dashboard Cite

Diamond thin films have outstanding optical, electrical, mechanical and thermal properties, which make these attractive for applications in a variety of current and future systems. In particular, the wide band gap, optical transparency and unusually high thermal conductivity of diamond thin films make them an ideal semiconductor for applications in current and future electronics. However, synthesis of diamond thin films with adequate quality remains a challenging task. Synthesis of diamond at low temperatures is even more challenging because of the difficulties in the nucleation and growth steps involved in diamond thin film deposition on a variety of substrates. Among the several deposition techniques for synthesising diamond films, plasma enhanced chemical vapour deposition is the most promising technique because of its potential for low temperature synthesis. Consequently, the first part of this paper reviews the current state of the nucleation and growth of diamond during chemical vapour deposition. A uniform and high nucleation density is a prerequisite for getting a good quality diamond film with significant growth rate. Also, since the process conditions for nucleation and growth steps are different, attempts are made in this review to identify the important parameters responsible for enhancing the nucleation and growth rates of diamond film. Describing the indispensable need for low temperature growth of diamond film, the second part of the paper reviews the research on the growth of diamond thin films at low temperatures. In spite of the slower kinetics at lower deposition temperatures, an attempt is made to identify the key processing conditions, which enhance the low temperature growth process. In addition, the mechanisms of diamond nucleation and growth are discussed based on the observations from in situ characterisation techniques such as Fourier transform infrared reflection absorption spectroscopy, real time spectroscopic ellipsometry and molecular beam mass spectroscopy.

show abstract

Section: R~imentioning

confidence: 93%

Section: Effect Of Variation In Processing Conditions and Additives I...mentioning

confidence: 99%

A review of nucleation, growth and low temperature synthesis of diamond thin films

Das¹,

Singh²

2007

International Materials Reviews

149

View full text Add to dashboard Cite

show abstract

“…[8] From an atomicscale computer simulation, [12] two-carbon-atom radicals are especially important to growth on (111) surfaces, while dominant CH 3 radicals are beneficial to the growth of (100) diamond planes. [13] Growth rate promptly decreases with decreasing filament temperature, as can be seen in Figure 4. The growth rate decreases from 3.2 to 0.057 lm/h when filament temperature decreases from 2000 to 1300 C. Sufficient hydrocarbon radical density is produced through the interaction of atomic hydrogen with methane, and methane itself is incompletely dissociated and atomic hydrogen concentration is low at a lower-than-normal filament temperature, which results in a low growth rate.…”

mentioning

confidence: 61%

Diamond Films Synthesized at Ultralow Filament Temperatures

Zhang¹,

Buck

2002

Adv. Eng. Mater.

View full text Add to dashboard Cite

In chemical vapor deposition of diamond films, a recent research challenge is to push the limits of boundary conditions. [1,2] These attempts may lead to the development of new deposition techniques and applications, and can also be expected to give insight into diamond growth mechanisms. In the hot-filament CVD method, it is known that filament and substrate temperature, chamber pressure, and gas concentration are the main quality control variables for diamond films. Typically, these parameters are 2000 C, 800 C, 40 mbar, and 1 % CH 4 in H 2 , respectively. Limiting deposition conditions have been investigated by many researchers. For example, the deposition pressure can be varied in either direction: higher up to nearly one atmosphere [3] to improve technical application, or lower to about 0.2 mbar [4] for basic research to reach conditions at which standard plasma deposition can be applied. The lowest substrate temperature is of special interest for many industrial applications: it is about 100 C. A high filament temperature of about 2890 C has been used to increase growth rate by using higher methane concentration. [5] Similarly, a question of common interest is the possibility of depositing diamond films at lower filament temperatures, because the growth of diamond films under these conditions might give a new insight into the deposition process. A lower filament temperature would have several advantages. Filaments would hold their shape better, resulting in stable deposition conditions. Moreover, filaments operating at a lower temperature would be better able to withstand mechanical disturbance and therefore have longer lifetimes.In the present study, diamond films were deposited in the low filament temperature range of 1300±1700 C. The synthesized diamond crystals were evaluated by X-ray diffraction (XRD) and scanning electron microscopy (SEM).The experiments were conducted in a typical hot-filament CVD system. The hot filament was made of a 0.5 mm diameter tantalum wire wound into 10 circles of inner diameter 2 mm. Si substrates were abraded with 0.1 lm diamond paste, then ultrasonically cleaned in acetone for 10 min before fixing to a boron nitride holder. During the deposition process, the total ambient pressure was kept at 40 mbar, while the flow rates of hydrogen and methane were controlled by mass flow controllers with 100 sccm total flow rate. The concentration of methane was fixed at 0.5 %. The temperatures of the filament and the substrate were 1300±1700 C and 650±950 C measured by an optical pyrometer and a K-type thermocouple, respectively. The distance between the filament and the substrate was 2±5 mm. Atomic hydrogen concentration, [H], as a function of filament temperature was measured by using the calorimetric method. [6] [H] was determined after calibration of the temperature difference DT measured by two thermocouples, one with a silver-coated tip and the other with a non-catalyzing quartz tip. The films produced under different filament temperature were characterized by SEM and by XRD usi...

show abstract

“…In PECVD reactor, noble gases like Ar help the ionization of working gas during the deposition of diamond films. Ar also increases the growth rate and modifies the surface morphology of the film 9. H 2 gas is used as a source of H and H + 10–11.…”

Section: Introductionmentioning

confidence: 99%

“…Ar also increases the growth rate and modifies the surface morphology of the film. [9] H 2 gas is used as a source of H and H þ . [10][11] H 2 , H, and H þ play an essential role in the destruction of polymeric carbon chain in surface etching of undesired species from surface, and help the production of activated radicals and ions by reacting with CH 4 and other hydrocarbons.…”

Section: Introductionmentioning

confidence: 99%

On the Plasma Chemistry of CH₄H₂Ar System Relevant to Diamond Deposition Process by Plasma Enhanced Chemical Vapor Deposition

Shokri

Yaghmaee

Sarani

2009

Plasma Processes & Polymers

View full text Add to dashboard Cite

Diamond films are extensively deposited using plasma enhanced chemical vapor deposition (PECVD). In this work, the most important non‐neutral plasma surface processes, which are needed to analyze the deposition mechanism of diamond films from plasma gas phase, are considered. Moreover, the role of ionic species, which is mostly neglected in deposition investigations, has been considered. To analyze the diamond deposition process, we use the reaction probability algorithm for different surface phenomena. Then, using different methods like Motz and Wise modified relation, the reaction probability is transformed to the mass action kinetic rate constant. Our results lead to the calculation of rate coefficients for non‐neutral gas‐surface reactions that take place during the diamond deposition from plasma in CH4H2Ar system.

show abstract

Role of xenon additive in microwave plasma-assisted (H2+CH4) chemical vapor deposition of diamond thin film

Cited by 9 publications

References 13 publications

A review of nucleation, growth and low temperature synthesis of diamond thin films

A review of nucleation, growth and low temperature synthesis of diamond thin films

Diamond Films Synthesized at Ultralow Filament Temperatures

On the Plasma Chemistry of CH₄H₂Ar System Relevant to Diamond Deposition Process by Plasma Enhanced Chemical Vapor Deposition

Contact Info

Product

Resources

About

Role of xenon additive in microwave plasma-assisted (H2+CH4) chemical vapor deposition of diamond thin film

Cited by 9 publications

References 13 publications

A review of nucleation, growth and low temperature synthesis of diamond thin films

A review of nucleation, growth and low temperature synthesis of diamond thin films

Diamond Films Synthesized at Ultralow Filament Temperatures

On the Plasma Chemistry of CH4H2Ar System Relevant to Diamond Deposition Process by Plasma Enhanced Chemical Vapor Deposition

Contact Info

Product

Resources

About

On the Plasma Chemistry of CH₄H₂Ar System Relevant to Diamond Deposition Process by Plasma Enhanced Chemical Vapor Deposition