Gas phase particulate formation in radiofrequency fluorocarbon plasmas

Buss, Richard J.; Hareland, W.A.

doi:10.1088/0963-0252/3/3/005

Cited by 20 publications

(14 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…What is perhaps more surprising is that there are sufficient densities of these small particulates in an etching discharge (as opposed to a deposition discharge like Si) to generate any DLLS signal at all in the first second of etching. In the case of a fluorocarbon etching discharge without a silicon substrate, Buss and Hareland [12] have reported substantially longer first appearance times (11 s) for polymeric CF x particles. With a wafer present in the discharge in this study, the DLLS measurements suggest initial particle growth is more akin to that observed by Boufendi and Bouchoule and points strongly to silicon etch products from the wafer surface playing a dominant role in initiating particle growth.…”

Section: Dynamic Laser Light Scattering In the Unm Reference Cellmentioning

confidence: 99%

Dusty Plasma Studies in the Gaseous Electronics Conference Reference Cell

Anderson¹,

Radovanov²

1995

J. Res. Natl. Inst. Stand. Technol.

View full text Add to dashboard Cite

Particle “dust” in processing plasmas is of critical concern to the semiconductor industry because of the threat particles pose to device yield. A number of important investigations into the formation, growth, charging, transport and consequences of particulate dust in plasmas have been made using the Gaseous Electronics Conference Reference Cell as the reactor test-bed. The greatest amount of work to date has been directed toward a better understanding of the role that electrostatic, ion drag, neutral fluid drag and gravitational forces play in governing the dynamic behavior of particle cloud motion. This has been accomplished by using laser light scattering (LLS) techniques to track the motion of suspended particle clouds in rf discharges. Also, statistical correlation’s in the fluctuation of scattered laser light intensity [dynamic laser light scattering (DLLS)] can be used to determine information about particle size, motion, and growth dynamics. These results are reviewed, along with recent work demonstrating that charged dust particles in a plasma can form a strongly coupled Coulomb liquid or solid. New results from DLSS experiments performed in the Reference Cell are presented that show process-induced dust particles confined in an electrostatic trap exhibit low-frequency oscillatory motion consistent with charge density wave (CDW) motion predicted for strongly coupled Coulomb liquids.

show abstract

Section: Dynamic Laser Light Scattering In the Unm Reference Cellmentioning

confidence: 99%

Dusty Plasma Studies in the Gaseous Electronics Conference Reference Cell

Anderson¹,

Radovanov²

1995

J. Res. Natl. Inst. Stand. Technol.

View full text Add to dashboard Cite

show abstract

“…the examples in [8] and in fluorocarbons such as CF 4 or C 2 F 6 (e.g. [8][9][10]). There is a significant number of publications dealing with polymerisation processes in such kind of plasmas.…”

Section: Introductionmentioning

confidence: 99%

Some Aspects of Reactive Complex Plasmas

Berndt¹,

Kovačević

Stefanović

et al. 2009

Contrib. Plasma Phys.

107

103

View full text Add to dashboard Cite

Reactive plasmas are nowadays widely used for technological applications. The spontaneous formation and growth of dust is a phenomenon frequently observed in such plasmas. The formation of dust particles has been observed in a great variety of different discharge types and in different kind of gases or gas mixtures. Due to the large variety of different phenomena that can be observed in reactive complex plasmas this article will address some selected (general) problems and examples that are specific for the physics and chemistry of such systems. These examples concern the formation and growth of dust particles in reactive plasmas, the mechanisms responsible for that growth processes, the spatial distribution of the dust particles within the discharge, the response of the plasma to the formation and growth of dust particles and some technological aspects.

show abstract

“…10,11 The onset time is the elapsed time from the ignition of the discharge until the light scattering signal from the particulates is first detected. The onset time was defined from the photodetector output signal which was recorded with the same amplification level as the time when the LLS signal begins to rise above the noise level ͑0.1 mV in our measuring system͒.…”

Section: Resultsmentioning

confidence: 99%

“…6 In this study, the effect of hydrogen addition on the particulate formation was examined in a RIE process of SiO 2 with a CF 4 /H 2 gas mixture. The particulate formation in plasma processes such as plasma enhanced chemical vapor deposition ͑PECVD͒, 7-9 etching, [10][11][12] and sputter deposition 13,14 has been widely studied by various groups from the viewpoint of the theoretical understanding of particulate transport, [15][16][17] the mechanism of formation in the plasma, 18,19 and suggestions to control the particulate contamination level. [20][21][22] The reduction of particulate formation level by the radio frequency ͑rf͒ power modulation method was reported by some groups [22][23][24] in the PECVD process of amorphous hydrogenated silicon with SiH 4 or SiH 4 /Ar plasmas.…”

Section: Introductionmentioning

confidence: 99%

Study of particulate formation and its control by a radio frequency power modulation in the reactive ion etching process of SiO2 with CF4/H2 plasma

Yeon

Whang

1997

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

View full text Add to dashboard Cite

Particulate formation in the reactive ion etching process of SiO2 with a CF4/H2 plasma was studied with the laser light scattering (LLS) method. The LLS onset time decreases drastically as the hydrogen percentage increases which indicates that the particulate formation was stimulated by the increase of the unsaturated fluorocarbon species as a result of the hydrogen addition. The onset time was also dependent on the substrate material. The measured onset time with a Si wafer was shorter than that with a SiO2 wafer. The onset time decreases very rapidly with the increase of the radio frequency (rf) power. A decrease of the LLS peak intensity was observed with the square wave modulation process of rf power. The change of the etch rate and the LLS peak intensity according to the change of the duty ratio shows that the optimal process condition, which satisfies high selectivity, high etch rate, and low particulate growth level, can be obtained with the rf modulation method. In the rf modulation process, both an increase in the off period and a decrease in the on period resulted in a decrease of the LLS signal in the particulate trap. It was observed that a change in the off period has a more pronounced effect on the change of the LLS signal intensity.

show abstract

Gas phase particulate formation in radiofrequency fluorocarbon plasmas

Cited by 20 publications

References 9 publications

Dusty Plasma Studies in the Gaseous Electronics Conference Reference Cell

Dusty Plasma Studies in the Gaseous Electronics Conference Reference Cell

Some Aspects of Reactive Complex Plasmas

Study of particulate formation and its control by a radio frequency power modulation in the reactive ion etching process of SiO2 with CF4/H2 plasma

Contact Info

Product

Resources

About