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15 Jul 1979

Volume 35, Issue 2, pp. 97-206

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Molecular beam epitaxial growth of low‐resistivity ZnSe films

Takafumi Yao, Yunosuke Makita, and Shigeru Maekawa

Appl. Phys. Lett. 35, 97 (1979); http://dx.doi.org/10.1063/1.91039 (2 pages) | Cited 28 times

Online Publication Date: 7 August 2008

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Single‐crystalline films of low‐resistivity ZnSe have been successfully grown by molecular beam epitaxy (MBE). The film shows good crystallinity, having a smooth and flat surface as revealed by RHEED and SEM investigations. The resistivity of as‐grown MBE ZnSe is low (typically ∼1 Ω cm) and the mobility of the film is relatively high (typically ∼300 cm2/V sec) at room temperature. The concentrations of the residual electrically active donor and acceptor centers are ND =8×1016 cm−3 and NA=6×1016 cm−3, respectively. The strong blue band‐edge photoluminescence peak is observed even at room temperature, and the luminescence intensity at longer wavelength is very weak.
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72.80.Ey III-V and II-VI semiconductors
73.61.Ng Insulators
78.55.-m Photoluminescence, properties and materials
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy

Observation of two‐dimensional electrons in LPE‐grown GaAs‐AlxGa1−xAs heterojunctions

D. C. Tsui and R. A. Logan

Appl. Phys. Lett. 35, 99 (1979); http://dx.doi.org/10.1063/1.91040 (3 pages) | Cited 23 times

Online Publication Date: 7 August 2008

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We have observed a two‐dimensional electron gas at the interface of asymmetrically doped GaAs‐AlxGa1−xAs heterojunctions grown by LPE. Our results demonstrate unequivocally that LPE can be used to grow GaAs‐AlxGa1−xAs heterojunctions with interfacial electrical properties comparable to those achieved by MBE.
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73.40.-c Electronic transport in interface structures
73.25.+i Surface conductivity and carrier phenomena
68.55.-a Thin film structure and morphology

Large‐angle acoustic‐beam steering in acoustically anisotropic crystal

E. G. Lean and W. H. Chen

Appl. Phys. Lett. 35, 101 (1979); http://dx.doi.org/10.1063/1.91055 (3 pages) | Cited 6 times

Online Publication Date: 7 August 2008

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We have demonstrated a unique scheme for electronically steering an acoustic beam over an angle large than 70° in a TeO2 crystal. The idea is based on the principle that the acoustic energy flow direction is always normal to the slowness curve in an acoustically anisotropic crystal. In the plane normal to the c axis of a TeO2 crystal and around the (110) axis, the shear wave acoustical energy flow directions can have a swing of more than 70° [from the (110) axis] by changing the wave‐vector direction only 3° from the (110) axis. Using a grating to diffract a shear wave propagation direction around the (110) axis, we have observed the wide‐angle acoustic‐beam steering effect by a laser probe.
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43.20.Fn Scattering of acoustic waves
43.60.-c Acoustic signal processing

Positive‐ion recovery scheme based on magnetic blocking of electrons

W. L. Stirling, J. Kim, H. H. Haselton, G. C. Barber, R. C. Davis, W. K. Dagenhart, W. L. Gardner, N. S. Ponte, C. C. Tsai, J. H. Whealton, and R. E. Wright

Appl. Phys. Lett. 35, 104 (1979); http://dx.doi.org/10.1063/1.91056 (3 pages) | Cited 4 times

Online Publication Date: 7 August 2008

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A method is described for making positive‐ion‐based neutral‐beam injection viable at energies of ≲100 keV per nucleon by recovering the energy of residual charged particles as electrical energy. The concept of transverse magnetic field blocking of electrons has been shown to be successful, and preliminary experimental results are presented.
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41.75.Ak Positive-ion beams
41.75.Cn Negative-ion beams
07.77.-n Atomic, molecular, and charged-particle sources and detectors

Observations consistent with self‐generated magnetic fields in CO2 laser‐produced plasmas

N. A. Ebrahim, M. C. Richardson, R. Fedosejevs, and U. Feldman

Appl. Phys. Lett. 35, 106 (1979); http://dx.doi.org/10.1063/1.91057 (3 pages) | Cited 8 times

Online Publication Date: 7 August 2008

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The spatial structure of extreme ultraviolet (XUV) line emission from plasmas produced by nanosecond CO2 laser pulses has been examined with a slitless normal‐incidence vacuum‐ultraviolet spectrograph in the 200–500‐Å spectral region. The anomalous structural behavior of these spectra is consistent with the existence of self‐generated magnetic fields. These fields could also explain the gross plasma structure observed through picosecond interferometry.
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52.50.Jm Plasma production and heating by laser beams (laser-foil, laser-cluster, etc.)
52.35.Fp Electrostatic waves and oscillations (e.g., ion-acoustic waves)

Surface analysis of field‐ion samples exposed to the plasma of the impurities studies experiment (ISX‐A) tokamak

G. L. Kellogg and R. E. Clausing

Appl. Phys. Lett. 35, 109 (1979); http://dx.doi.org/10.1063/1.91058 (3 pages) | Cited 2 times

Online Publication Date: 7 August 2008

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Measurements of the modifications to the surface of field‐emitter samples (tips) exposed to plasma discharges in the impurities studies experiment (ISX‐A) tokamak have been carried out for the first time in order to help further identify the physical processes occurring at the tokamak wall during machine operation. The specimen tips were exposed to 40 high‐power hydrogen discharges in ISX‐A at a position 5.0 cm back from the plasma edge defined by carbon and molybdenum limiters. In contrast to results obtained on silicon samples exposed at a similar location in ISX‐A using Rutherford ion backscattering analysis, field‐ion images of tungsten tips taken before and after exposure indicate that no structural rearrangement of the specimen near‐surface region occurred, even on an atomic scale. Contaminant films 60±10 Å thick, deposited on the specimen surfaces during exposure, were observed in the transmission electron microscope. Control tips, placed in the tokamak during the discharges but shielded from direct plasma exposure, remained free of such deposits. Imaging atom‐probe depth profiles into the exposed sample substrates revealed that neither plasma nor impurity species were implanted beyond the deposited surface films. The results from this study are compared with those from earlier analyses of samples exposed in the Princeton large torus (PLT) using similar techniques and also with the results of analyses of macroscopic samples exposed at the same ISX‐A location using other surface‐sensitive techniques.
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79.70.+q Field emission, ionization, evaporation, and desorption
72.30.+q High-frequency effects; plasma effects
52.90.+z Other topics in physics of plasmas and electric discharges (restricted to new topics in section 52)

Very‐low‐noise silicon avalanche photodiodes made by the channeling of aluminum in 〈110〉 silicon

E. T. J. M. Smeets and J. Politiek

Appl. Phys. Lett. 35, 112 (1979); http://dx.doi.org/10.1063/1.91059 (2 pages)

Online Publication Date: 7 August 2008

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A silicon n+pπp+ reach‐through avalanche photodiode is described, where the p region is made by the channeling of aluminum atoms in 〈110〉 silicon. Effective noise factors of about 0.01 have been realized. The influence of the channeling on device parameters is discussed.
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72.70.+m Noise processes and phenomena
42.79.Sz Optical communication systems, multiplexers, and demultiplexers
85.60.Gz Photodetectors (including infrared and CCD detectors)

Metastable 75As concentrations formed by scanned cw e‐beam annealing of 75As‐implanted silicon

J. L. Regolini, T. W. Sigmon, and J. F. Gibbons

Appl. Phys. Lett. 35, 114 (1979); http://dx.doi.org/10.1063/1.91060 (3 pages) | Cited 16 times

Online Publication Date: 7 August 2008

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The incorporation of 75As into substitutional lattice sites in silicon in excess of 1021 cm−3 is reported. This has been accomplished by both a scanned cw e‐beam and a scanned cw laser operating with dwell times in the range of milliseconds. Both electron concentration (using differential van der Pauw) and atom location measurements (using MeV ion channeling) are reported. Standard thermal processing indicates that these layers are metastable.
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61.72.U- Doping and impurity implantation
78.40.Fy Semiconductors
72.80.Ey III-V and II-VI semiconductors
81.40.Ef Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization

Time‐dependent voltage measurement of pulsating AlxGa1−xAs double‐heterostructure lasers

J. P. van der Ziel

Appl. Phys. Lett. 35, 116 (1979); http://dx.doi.org/10.1063/1.91061 (3 pages) | Cited 7 times

Online Publication Date: 7 August 2008

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The optical pulsations in the output of semiconductor lasers are accompanied by a time variation of the diode voltage. During the optical pulse the voltage decreases by ≈2.5 mV, corresponding to a decrease in carrier population. In the interval between pulses the voltage recovers exponentialy with a 1.3±0.2‐nsec time constant to its prepulse value as a result of carrier injection into the active region.
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42.55.Px Semiconductor lasers; laser diodes
42.60.Fc Modulation, tuning, and mode locking
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Two‐dimensional average concentration measurements in a jet flow by Raman scattering

Bruce F. Webber, Marshall B. Long, and Richard K. Chang

Appl. Phys. Lett. 35, 119 (1979); http://dx.doi.org/10.1063/1.91042 (3 pages) | Cited 7 times

Online Publication Date: 7 August 2008

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A multipass cell arrangement and a low‐light‐level television camera were used to obtain a simultaneous digitized two‐dimensional concentration profile of CH4 flowing from an axisymmetric jet by measuring the spontaneous Raman radiation. Because the Raman technique is species selective, the concentration profile of the N2 contained in the surrounding gas (air) was also determined for CH4 and SF6 jets under the same conditions. Comparison is made with the concentration profiles determined by Mie scattering in seeded jets.
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47.80.-v Instrumentation and measurement methods in fluid dynamics
47.27.-i Turbulent flows
47.27.T- Turbulent transport processes

Photoacoustic characterization of cw argon‐ion laser irradiation of Ge

J. F. McClelland and R. N. Kniseley

Appl. Phys. Lett. 35, 121 (1979); http://dx.doi.org/10.1063/1.91043 (4 pages) | Cited 8 times

Online Publication Date: 7 August 2008

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Photoacoustic detection has been used to characterize cw argon‐ion laser irradiation of Ge. Laser‐induced heating, damage, and melting are studied. The heating process is seen to be nonlinear with incident laser power until close to melting. Two laser‐induced‐damage time constants are obtained associated with thermal etching and oxidation. An incident power level of 2.24 W is estimated to initiate the melting of an undamaged Ge surface under the experimental conditions described.
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79.20.Ds Laser-beam impact phenomena
42.62.-b Laser applications
81.40.Tv Optical and dielectric properties related to treatment conditions
68.35.-p Solid surfaces and solid-solid interfaces: structure and energetics

The photon avalanche: A new phenomenon in Pr3+‐based infrared quantum counters

Jay S. Chivian, W. E. Case, and D. D. Eden

Appl. Phys. Lett. 35, 124 (1979); http://dx.doi.org/10.1063/1.91044 (2 pages) | Cited 124 times

Online Publication Date: 7 August 2008

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Studies of laser‐pumped Pr3+ infrared quantum counters have led to the discovery of a new photon avalanche region, occurring when pump flux exceeds a certain critical value. Infrared output near 4.5 μm is associated with the large visible output, and pump power is strongly absorbed. Critical pump power density is in the range 1.2–12.2 W/cm2.
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32.50.+d Fluorescence, phosphorescence (including quenching)
42.62.-b Laser applications
42.50.Md Optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals, optical nutation, and self-induced transparency
78.90.+t Other topics in optical properties, condensed matter spectroscopy and other interactions of particles and radiation with condensed matter (restricted to new topics in section 78)

Kinetics and fusion laser potential for the terbium chloride–aluminum chloride vapor complex

Ralph R. Jacobs and William F. Krupke

Appl. Phys. Lett. 35, 126 (1979); http://dx.doi.org/10.1063/1.91045 (3 pages) | Cited 5 times

Online Publication Date: 7 August 2008

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Fluorescence responses of the Tb3+ : 5D3 and 5D4 metastable levels are presented for the terbium chloride–aluminum chloride vapor complex excited by pulsed KrF laser radiation. Assuming unit quantum yield, excited‐state densities as high as 3×1016 cm−3 (10 J/l) are inferred for the experimental conditions and maintained for times ≳10 μs.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
31.70.Hq Time-dependent phenomena: excitation and relaxation processes, and reaction rates
28.52.-s Fusion reactors

A high‐power CO2 waveguide laser

G. M. Carter and S. Marcus

Appl. Phys. Lett. 35, 129 (1979); http://dx.doi.org/10.1063/1.91046 (2 pages) | Cited 7 times

Online Publication Date: 7 August 2008

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A CO2 waveguide laser from which 39.5 W (51 W/m) has been obtained is described. These values are greater than any previously reported. Data on the temperature dependence of the output power are presented and discussed. An analysis was performed from which the small‐signal gain (0.22 cm−1) and saturation power (35 W) at conditions of maximum power output were obtained. It is shown that the assumption of distributed loss gives a better fit to the observed laser output than does that of concentrated loss at the mirrors.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Single‐mode fiber multiterminal star directional coupler

S. K. Sheem and T. G. Giallorenzi

Appl. Phys. Lett. 35, 131 (1979); http://dx.doi.org/10.1063/1.91047 (3 pages) | Cited 5 times

Online Publication Date: 7 August 2008

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We report the first single‐mode multiterminal star coupler in which fibers are grouped into sets of three fibers. The three fibers in each set were than braided over some length before one or more of the fibers of each set are interchanged with their counterparts in other sets. We utilized the encapsulated etching technique reported earlier to overcome the peculiar geometric problems associated with single‐mode fibers. Excellent output uniformity and very low throughput loss have been achieved in these devices because of our new designs. We also present coupled‐mode theoretical analysis which can be used to describe these new single‐mode star couplers.
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42.81.-i Fiber optics
42.79.Sz Optical communication systems, multiplexers, and demultiplexers
42.79.Gn Optical waveguides and couplers

Efficient XeF laser excited by a proton beam

J. G. Eden, J. Golden, R. A. Mahaffey, J. A. Pasour, and R. W. Waynant

Appl. Phys. Lett. 35, 133 (1979); http://dx.doi.org/10.1063/1.91048 (4 pages) | Cited 4 times

Online Publication Date: 7 August 2008

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The efficient generation of stimulated emission from XeF at 351 and 353 nm has been achieved by pumping RG/Xe/NF3 gas mixtures (RG=argon, neon, or helium) with an intense (∼10 A cm−2) beam of ∼200‐keV protons. For an active medium (T=300 °K) consisting of Ar, Xe, and NF3 at a total pressure of 1 atm and 30% cavity output coupling, the volumetric output, efficiency, and threshold pump power for the laser were determined to be 5–10 J/liter amagat, 1.7±0.7%, and 1.5 MW cm−3, respectively. Much lower efficiencies were obtained for neon and helium diluent mixtures.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
29.25.Lg Ion sources: polarized
29.25.Ni Ion sources: positive and negative

Annihilation of frozen‐in point defects in GaP by thermal and recombination‐induced processes

C. Werkhoven, J. H. T. Hengst, and C. van Opdorp

Appl. Phys. Lett. 35, 136 (1979); http://dx.doi.org/10.1063/1.91049 (3 pages) | Cited 10 times

Online Publication Date: 7 August 2008

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Minority‐carrier‐lifetime measurements on heat‐treated rapidly cooled LEC‐grown GaP reveal strong nonradiative recombination at frozen‐in point defects. Cathodoluminescence line scan studies show that during slow cooling the point defects introduced during heating are removed by diffusion to dislocations and microdefects; the intensity of the resulting luminescence halos around the dislocations depends on heat treatment, due to variations in minority‐carrier lifetime. Alternatively, frozen‐in point defects can also be annihilated by photon excitation and by electron‐beam excitation. In these cases, phonons liberated during nonradiative recombination at the point defects excite defect motions which result in annihilation reactions; these are probably recombination reactions between Frenkel pairs.
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72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
72.80.Ey III-V and II-VI semiconductors
78.40.Fy Semiconductors
78.60.Hk Cathodoluminescence, ionoluminescence

Chemically pumped iodine laser

R. J. Richardson and C. E. Wiswall

Appl. Phys. Lett. 35, 138 (1979); http://dx.doi.org/10.1063/1.91050 (2 pages) | Cited 46 times

Online Publication Date: 7 August 2008

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A chemically pumped iodine‐atom laser is described based on electronic energy transfer to atomic iodine from chemically generated O2(1Δ). The total extracted power (10 W) is approximately 3% of the power contained in the O2(1Δ) flow.
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42.55.Ks Chemical lasers
78.60.Ps Chemiluminescence
82.30.Hk Chemical exchanges (substitution, atom transfer, abstraction, disproportionation, and group exchange)

Soft x‐ray and vacuum‐ultraviolet spectroscopy of ion‐beam‐heated thin targets

E. J. T. Burns, D. J. Johnson, A. V. Farnsworth, G. W. Kuswa, G. A. Doschek, and U. Feldman

Appl. Phys. Lett. 35, 140 (1979); http://dx.doi.org/10.1063/1.91051 (3 pages) | Cited 2 times

Online Publication Date: 7 August 2008

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XUV spectroscopy utilizing a 1‐m grazing incidence spectrograph and photoelectric diodes is used to determine the response of approximately one‐proton‐range‐thick planar targets to an intense beam of hydrogen and carbon ions. Electron temperature, brightness temperature, and total radiated power are then compared with radiation‐hydrodynamic calculations to determine the ion‐beam energy deposition and incident current density. Incident current densities of 25–35 kA/cm2 with 80% proton current and 20% singly ionized carbon ion current are consistent with the spectroscopic measurements.
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78.40.-q Absorption and reflection spectra: visible and ultraviolet
78.90.+t Other topics in optical properties, condensed matter spectroscopy and other interactions of particles and radiation with condensed matter (restricted to new topics in section 78)
41.75.Ak Positive-ion beams
41.75.Cn Negative-ion beams

Stability enhancement in electron‐beam‐sustained excimer laser discharges

Robert T. Brown and William L. Nighan

Appl. Phys. Lett. 35, 142 (1979); http://dx.doi.org/10.1063/1.91052 (3 pages) | Cited 5 times

Online Publication Date: 7 August 2008

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Techniques are described for prolonging the duration of stable e‐beam‐controlled excimer laser discharges, including: temporal tailoring of either the discharge voltage or the ionization source and kinetics modification by way of additives. Theoretical and experimental results are presented for KrF∗ laser discharges.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
52.35.Py Macroinstabilities (hydromagnetic, e.g., kink, fire-hose, mirror, ballooning, tearing, trapped-particle, flute, Rayleigh-Taylor, etc.)
52.80.-s Electric discharges

Modified balanced‐bridge switch with two straight waveguides

Osamu Mikami and Sakae Zembutsu

Appl. Phys. Lett. 35, 145 (1979); http://dx.doi.org/10.1063/1.91053 (3 pages) | Cited 5 times

Online Publication Date: 7 August 2008

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A new balanced‐bridge‐switch configuration is presented. This configuration has two 3‐dB couplers and an electro‐optic phase shifter formed only by two parallel straight waveguides. That is, these three regions were directly interconnected through no extra waveguides. The phase shifter was realized by unsynchronizing the phase of two adjacent waveguides by loading a high‐index film on one of them. The modified balanced‐bridge switch was fabricated in c‐plate LiNbO3 using Ti‐diffused waveguides and a Se‐S–based chalcogenide glass film. Waveguide dimensions were 8‐μm width, 5‐μm gap, and 16‐mm interaction length. Switch characteristics at 1.15‐ μm wavelength were 3.3 V half‐wave voltage, 8.7‐dB crosstalk, and 4.2‐dB insertion loss.
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42.79.Gn Optical waveguides and couplers
42.60.Fc Modulation, tuning, and mode locking

Selection of high‐power nanosecond pulses from large‐aperture CO2 oscillators

V. V. Apollonov, P. B. Corkum, and R. S. Taylor

Appl. Phys. Lett. 35, 147 (1979); http://dx.doi.org/10.1063/1.91054 (3 pages) | Cited 3 times

Online Publication Date: 7 August 2008

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A high‐contrast 6‐J 3‐ns pulse has been obtained from an injection mode‐locked TEA CO2 oscillator using an extracavity SF6‐He saturable absorber to suppress the prepulse energy to <1 μJ and an intracavity semiconductor transmission switch to suppress postpulses. The techniques described in this paper will allow the frequency and transverse‐mode control of an oscillator to be maintained to much higher powers than are presently possible.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.By Design of specific laser systems

Four‐wave interactions in acoustoelectric integrating correlators

R. W. Ralston and E. Stern

Appl. Phys. Lett. 35, 150 (1979); http://dx.doi.org/10.1063/1.91062 (3 pages)

Online Publication Date: 7 August 2008

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Four‐wave acoustoelectric interactions have been observed in an integrating correlator which provide both significantly improved device performance over that achieved with three‐wave interactions and make possible a unique signal‐processing function: triple‐product correlation. These interactions involve the differential delay, mixing, and time integration of two (ω1, ω2) surface acoustic waves (SAW’s) counterpropagating on a LiNbO3 delay line in the presence of a uniform (ω3=ω1+ω2) pump applied to a PtSi diode array and a stationary wave of charge stored in the diode array. A narrow (∼350 nm) air gap provides coupling of the array to the evanescent rf fields accompanying the SAW’s; thus, the silicon nonlinearities provide local mixing of the three rf fields and a fourth field, at dc, which accompanies the stored charge pattern. Two four‐wave interactions have been cascaded (the first creates the stored charge, the second scans the charge pattern) to demonstrate the correlation of a waveform with a time‐bandwidth product in excess of 10 000.
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72.50.+b Acoustoelectric effects
43.35.-c Ultrasonics, quantum acoustics, and physical effects of sound
73.50.Rb Acoustoelectric and magnetoacoustic effects
77.65.Dq Acoustoelectric effects and surface acoustic waves (SAW) in piezoelectrics
43.60.Gk Space-time signal processing, other than matched field processing
72.20.Ht High-field and nonlinear effects

Visible photoabsorption by noble‐gas trimer ions

H. H. Michels, R. H. Hobbs, and L. A. Wright

Appl. Phys. Lett. 35, 153 (1979); http://dx.doi.org/10.1063/1.91063 (3 pages) | Cited 37 times

Online Publication Date: 7 August 2008

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A study of the electronic structure and photoabsorption characteristics of noble‐gas trimer ions has been carried out using quantum mechanical methods. This study includes detailed density functional calculations of the potential energy surfaces for a prototype system, Ar+3, an analysis of the spectroscopic properties of the ground state of this ion, and prediction of the strong absorption bands. Studies in D3h, C2v, and D∞h symmetries were carried out. The lowest state of Ar+3 corresponds to the degenerate 2E′ symmetry with an indicated dissociation energy of 0.17 eV relative to Ar+2 (A 2Σ+u)+Ar (1S0). This trimer ion exhibits a small Jahn‐Teller distortion which does not significantly alter our conclusions concerning the ground‐state stability or absorption characteristics. A strong and very broad photoabsorption band (λ=480–670 nm) is predicted for the 2E′→2A′1 transition of this trimer ion. This suggests that such species may be important in the analysis of loss mechanisms in visible excimer lasers operating under high‐pressure conditions with mixtures containing the noble gases.
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33.20.Kf Visible spectra
31.15.-p Calculations and mathematical techniques in atomic and molecular physics
31.50.Df Potential energy surfaces for excited electronic states

Laser‐irradiation effects on unencapsulated GaAs studied by capacitance spectroscopy

Yoshihiko Yuba, Kenji Gamo, Kouichi Murakami, and Susumu Namba

Appl. Phys. Lett. 35, 156 (1979); http://dx.doi.org/10.1063/1.91041 (3 pages) | Cited 7 times

Online Publication Date: 7 August 2008

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The effect of Q‐switched ruby‐laser irradiation on unencapsulated unimplanted bulk GaAs has been investigated by means of deep‐level transient spectroscopy (DLTS) and C‐V carrier profiling. It was found that the concentration of a deep‐level center (Ec−0.83 eV) assigned to the A center decreases considerably as a result of laser irradiation, and that no deep levels (electron traps) more than 3×1013/cm3 are induced by the laser irradiation on the uncapped surface at a power level suitable for the recrystallization of an amorphous layer produced by ion implantation. No significant change in the free‐carrier profile at a depth deeper than 1500 Å from the surface was observed after the laser irradiation.
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79.20.Ds Laser-beam impact phenomena
78.40.Fy Semiconductors
81.40.-z Treatment of materials and its effects on microstructure, nanostructure, and properties
61.72.U- Doping and impurity implantation
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