CW CO2 laser CVD of amorphous hydrogenated silicon (a-Si:H): influence of the deposition geometry

ABSTRACTAmorphous hydrogenated silicon (a-Si:H) films were deposited from disilane at substrate temperatures between 180 and 390 °C using a F2-laser (157 nm) in a parallel configuration. Material properties such as hydrogen content, SiH and SiH2 group concentration, photo-and dark conductivity, band-gap energy and the Urbach parameter were determined as a function of the deposition temperature. The material with the best optical and electronical properties was found for a substrate temperature of 260 °C. Using argon as the buffer gas instead of helium results in films of poor quality.

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Investigations on cw CO2-laser induced welding plasmas using differential interferometry

10.2351/1.5059248 ◽

1999 ◽

Cited By ~ 1

Author(s):

Henrik Schittenhelm ◽

Jürgen Müller ◽

Peter Berger ◽

Helmut Hügel

Keyword(s):

Co2 Laser ◽

Differential Interferometry ◽

Cw Co2 Laser

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Spatial temperature distribution in CW CO2 laser photosensitized reactions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19841354 ◽

1984 ◽

Vol 49 (6) ◽

pp. 1354-1359 ◽

Cited By ~ 1

Author(s):

Pavel Kubát ◽

Josef Pola

Keyword(s):

Temperature Distribution ◽

Chemical Reactions ◽

Co2 Laser ◽

Computational Procedure ◽

Heat Convection ◽

Inert Gas ◽

Spatial Temperature Distribution ◽

Cw Co2 Laser ◽

Spatial Temperature

The temperature distribution in gaseous SF6 and SF6-inert gas samples under irradiation with cw CO2 laser measured by a thermocouple technique is confronted with the results of a computational procedure neglecting heat convection. The results are helpful in understanding the effect of the inert gas on the distribution of temperature and the size of the reacting hot volume in the cw laser-photosensitized chemical reactions.

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Cw CO2 laser driven oxidation of some perhalogenocycloalkenes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19910398 ◽

1991 ◽

Vol 56 (2) ◽

pp. 398-405 ◽

Cited By ~ 2

Author(s):

Josef Pola ◽

Jaroslav Včelák ◽

Zdeněk Chvátal

Keyword(s):

Co2 Laser ◽

Total Pressure ◽

Diels Alder ◽

Title Reaction ◽

Consecutive Reactions ◽

Cw Co2 Laser

The title reaction of hexafluorocyclobutene, 1,2-dichloro-3,3,4,4-tetrafluorocyclobutene and decafluorocyclohexene studied at total pressure 13.3 and 16 kPa yield oxalyl halides COX.COX (X = F, Cl) and C2F4 that undergo consecutive reactions to COF2, CO and X2. The oxidation of decafluorocyclohexene is preceded by retro-Diels-Alder decomposition affording hexafluorocyclobutene and C2F4. Two alternative mechanisms for the oxidation of the cyclobutenes are presented, one involving a novel cleavage of intermediary bicyclic dioxetanes. The decomposition of oxalyl fluoride into COF2 and CO is favored over its oxidation.

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