Determination of Neutral-Atom Density in a Highly Ionized Decaying Hydrogen Plasma

AbstractThe use of dry hydrogen plasma etching is evaluated for determination of GaN polarity and critically compared to wet etching in NaOH. It is shown that hydrogen plasma etching is effective in revealing inversion domains (IDs) and some types of dislocations. This is because the surface morphology is unchanged by the hydrogen treatment, and, hence, the surface reactivity is not masked.

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Determination of the imploded mass in laser-imploded shell targets

Laser and Particle Beams ◽

10.1017/s0263034600002184 ◽

1986 ◽

Vol 4 (3-4) ◽

pp. 507-514 ◽

Cited By ~ 3

Author(s):

S. Denus ◽

J. Farny ◽

M. Grudzień ◽

W. Mróz ◽

J. Wołowski ◽

...

Keyword(s):

Neutral Atom ◽

Neutral Particle ◽

Laser System ◽

Semiconductor Diode ◽

Velocity Spectrum ◽

Particle Detector ◽

Beam Laser ◽

Atom Flux ◽

Time Of Flight Method

A new method of experimental measurement of the imploded mass of laser-imploded shell targets is proposed. This method is based on simultaneous measurements of the velocity spectrum of the neutral atom flux emitted from the imploded part of the target, and the total energy carried by them. A semiconductor diode with a shallowly located p – n junction was used as the low energy neutral particle detector. By means of the time of flight method neutral atom fluxes with velocities υ ∼ (0·6 − 1·8) × 107cm/s were registered in experiments carried out on the 6-beam laser system “Delfin”.

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Spectrographic Determination of Indium and Gallium in Cadmium Telluride Using Alumina-Cup Electrode

Applied Spectroscopy ◽

10.1366/000370269774381067 ◽

1969 ◽

Vol 23 (2) ◽

pp. 115-120 ◽

Cited By ~ 3

Author(s):

Shigeru Ohtsuka

Keyword(s):

Cadmium Telluride ◽

Coefficient Of Variation ◽

Neutral Atom ◽

Low Voltage ◽

Approximate Determination ◽

Spectrographic Determination ◽

Suitable Amount ◽

Graphite Rod

A spectrographic technique using a specially designed cup electrode is proposed for the determination of indium and gallium in a solution of cadmium telluride. The electrode consists of an alumina cup which serves as a reservoir for the sample and a central tungsten rod supporting a graphite rod. It allows the excitation under low voltage over damped discharge. The method is especially useful for analysis of small quantities of material. The addition of a suitable amount of lithium has been found to enhance the intensity of the neutral atom lines of indium and gallium. Approximate determination limits for indium and gallium are 0.5 μg/ml, and the coefficient of variation for the determination is about 6% at the 5 μg/ml level.

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