Laser-induced breakdown spectroscopy of trisilane using infrared CO2 laser pulses

Abstract

Synthesis and photoluminescence of fluorinated graphene quantum dots Appl. Phys. Lett. 102, 013111 (2013) The luminescence characteristics of CsI(Na) crystal under α and X/γ excitation J. Appl. Phys. 113, 023101 (2013) Structural and optoelectronic properties of Eu2+-doped nanoscale barium titanates of pseudo-cubic form J. Appl. Phys. 112, 124321 (2012) Quantum yield of luminescence of Ag nanoclusters dispersed within transparent bulk glass vs. glass composition and temperature Appl. Phys. Lett. 101, 251106 (2012) Additional information on J. Appl. Phys. The plasma produced in trisilane ͑Si 3 H 8 ͒ at room temperature and pressures ranging from 50 to 10 3 Pa by laser-induced breakdown ͑LIB͒ has been investigated. The ultraviolet-visible-near infrared emission generated by high-power IR CO 2 laser pulses in Si 3 H 8 has been studied by means of optical emission spectroscopy. Optical breakdown threshold intensities in trisilane at 10.591 m for laser pulse lengths of 100 ns have been measured as a function of gas pressure. The strong emission observed in the plasma region is mainly due to electronic relaxation of excited atomic H and Si and ionic fragments Si + , Si 2+ , and Si 3+ . An excitation temperature T exc = 5600± 300 K was calculated by means of H atomic lines assuming local thermodynamic equilibrium. The physical processes leading to LIB of trisilane in the power density range 0.28 GW cm −2 Ͻ J Ͻ 3.99 GW cm −2 have been analyzed. From our experimental observations we can propose that, although the first electrons must appear via multiphoton ionization, electron cascade is the main mechanism responsible for the breakdown in trisilane.

On the use of laser induced breakdown spectroscopy to characterize the naturally existing crystal in Pakistan and its optical emission spectrum

“…A doublet due to the 3s 2 4p 2 P 1/2,3/2 → 3s3p 2 2 D 3/2,5/2 transitions at 385.71 and 386.37 nm, a strong doublet of Si II lines at 413 nm due to the 3s 2 4f 2 F 5/2,7/2 → 3s 2 3d 2 D 3/2,5/2 transitions, a doublet due to the 3s 2 4d 2 D 3/2,5/2 → 3s 2 4p 2 P 1/2,3/2 transitions at 504.24 and 505.74 nm and another doublet due to the 3s 2 4p 2 P 1/2,3/2 → 3s 2 4s 2 S 1/2 transitions at 634.89 and 637.31 nm which lies adjacent to the hydrogen Hα line at 656.28 nm. Camacho et al [16] reported the LIBS spectra of silicon using a CO 2 who observed a number of neutral silicon lines in addition to some lines due to singly and doubly ionized silicon ions. Four Si + doublets (see above) have been observed but two doublets reported by Camacho et al [16] around 596 nm and around 536 nm are absent; may be too weak to be observed under the present experimental conditions.…”

“…Camacho et al [16] reported the LIBS spectra of silicon using a CO 2 who observed a number of neutral silicon lines in addition to some lines due to singly and doubly ionized silicon ions. Four Si + doublets (see above) have been observed but two doublets reported by Camacho et al [16] around 596 nm and around 536 nm are absent; may be too weak to be observed under the present experimental conditions. In addition, not a single line due to doubly ionized silicon has been detected.…”

“…Liu et al [8] studied the silicon plasma generated by a nanosecond (ns) Nd:YAG laser at 266 nm and reported the plasma temperature in the range of 20,000-70,000 K whereas the electron density determined from the Stark broadening of the Si I line at 288. 16 nm was in the range of 10 18 -10 19 cm −3 . Milan and Laserna [9] observed the silicon ablation using a Nd:YAG laser (532 nm) and reported the electron temperature in the range of 6000-9000 K and the electron number density of the order of 10 18 cm − 3 .…”

“…The time resolved plasma properties for the double pulse laser induced breakdown spectroscopy of silicon was reported by Mao et al [15] using two laser pulses at 1064 nm and studied the plasma properties as a function of delay between the laser pulses and inferred an increase in the plasma properties and crater dimensions. Camacho et al [16] reported the laser induced breakdown spectroscopy of trisilane (Si 3 H 8 ) using infrared CO 2 laser pulses and observed strong emission due to Si and ionic fragments Si + , Si 2+ , and Si 3+ . The excitation temperature determined from the singly ionized silicon lines was 26,000 ± 3000 K and that from the hydrogen atomic lines as 5600 ± 300 K whereas the electron density around 1.44 × 10 16 cm −3 was estimated from the Stark broadened H β line profile.…”

Optical emission spectroscopic study of plasma plumes generated by IR CO2pulsed laser on carbon targets

“…For laser ablation of carbon, OES studies in different atmospheres are reported and these studies have yielded many interesting results . Detailed studies of laser-induced breakdown spectroscopy on N 2 and Si 3 H 8 in the gas phase have been recently made in our laboratory [32,33].…”