Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Seksan Dheandhanoo is active.

Publication


Featured researches published by Seksan Dheandhanoo.


Applied Optics | 2005

Quantitative absorption spectroscopy of residual water vapor in high-purity gases: pressure broadening of the 1.39253-μm H 2 O transition by N 2 , HCl, HBr, Cl 2 , and O 2

Vasil Vorsa; Seksan Dheandhanoo; Suhas Narayan Ketkar; Joseph T. Hodges

We determined the respective pressure-broadening coefficients of HCl, HBr, Cl2, and O2 (expressed relative to that of the reference gas N2) for the (v1,v2,v3)J(Ka,Kc) = (0,0,0)3(0,3) --> (1,0,1)2(0,2) rovibrational transition of H2 16O that occurs at 1.39253 microm. The experiment used a continuous-wave cavity ring-down spectroscopy analyzer to measure the peak absorption losses as a function of added moisture concentration. The measured pressure-broadening coefficients for HCl, HBr, Cl2, and O2 are, respectively, 2.76, 2.48, 1.39, and 0.49 times that of the N2 pressure-broadening coefficient, and detection limits for water vapor range from 0.22 nmol mol(-1) for O2 matrix gas to 2.3 nmol mol(-1) for HBr matrix gas. The degradation of the detection limit (relative to the N2 matrix gas) is ascribed to a pressure-broadening-induced reduction in peak absorption cross section and to elevated background loss from the matrix gas.


Review of Scientific Instruments | 2000

Atmospheric pressure sample inlet for mass spectrometers

Seksan Dheandhanoo; Ralph J. Ciotti; Suhas Narayan Ketkar

An inlet for a mass spectrometer has been developed for direct sampling of gases over a wide range of pressure (1–760 Torr). The sample inlet is composed of two small orifices that form a pressure reduction region. These orifices are used to limit the flow of sample gas into the mass spectrometer. The pressure inside the pressure reduction region is regulated by a needle valve and a vacuum pump. The flow of gas through the orifices is viscous. The inlet is made of stainless steel and operated at high temperature to prevent surface adsorption and corrosion. Its adaptability to a wide range of pressures is very useful for monitoring process gases during manufacturing processes of microelectronic devices. This inlet can be used for effluent gas analysis at 760 Torr as well as for in situ monitoring of the semiconductor equipment at pressures less than 5 Torr. The inlet provides a fast response to changes in the constituents of gas samples without memory effects. The sample inlet has been tested extensively i...


Archive | 1996

Dynamic dilution system

Robert Gordon Ridgeway; Richard Vincent Pearce; Peter James Maroulis; Seksan Dheandhanoo; Suhas Narayan Ketkar


Archive | 2000

Method of improving the performance of an ion mobility spectrometer used to detect trace atmospheric impurities in gases

Suhas Narayan Ketkar; Seksan Dheandhanoo


Journal of the IEST | 1998

EMPIRICAL VALIDATION OF A GAS DISTRIBUTION SYSTEM MOISTURE DRYDOWN MODEL

Seksan Dheandhanoo; James Yang; Ralph J. Ciotti; David Yesenofski


Solid State Technology | 2001

Modeling the characteristics of gas system dry-down

Seksan Dheandhanoo; James Yang; Michael D. Wagner


Archive | 2001

Method for operating an ion mobility spectrometer used to detect trace atmospheric impurities in gases

Seksan Dheandhanoo; Suhas Narayan Ketkar


Archive | 2000

Apparatus for control of gas flow into a mass spectrometer using a series of small orifices

Seksan Dheandhanoo; Ralph J. Ciotti; Suhas Narayan Ketkar; Richard Vincent Pearce


Archive | 2001

Total impurity monitor for gases

Suhas Narayan Ketkar; Seksan Dheandhanoo


Archive | 2001

Verfahren zur Leistungssteigerung eines Ionenbeweglichkeitsspektrometers zur Detektion atmosphärischer Spurenverunreinigungen in Gasen A method to improve performance of an ion mobility spectrometer for the detection of atmospheric trace impurities in gases

Suhas Narayan Ketkar; Seksan Dheandhanoo

Collaboration


Dive into the Seksan Dheandhanoo's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar

Joseph T. Hodges

National Institute of Standards and Technology

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge