Temperature Dependence of Compositional Disordering of Gaas-Alas Superlattices During Mev Kr Irradiation

1990 ◽  
Vol 198 ◽  
Author(s):  
R. P. Bryan ◽  
L. M. Miller ◽  
T. M. Cockerill ◽  
J. J. Coleman ◽  
J. L. Klatt ◽  
...  
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Chemical Vapor ◽  
Miscibility Gap ◽  
Enhanced Diffusion ◽  
Specimen Temperature ◽  
Radiation Enhanced Diffusion ◽  
Increasing Temperature ◽  
Secondary Ion

ABSTRACTThe influence of the specimen temperature during MeV Kr irradiation on the extent of compositional disordering in GaAs-AlAs superlattices (SLs) has been determined. We have investigated whether radiation-enhanced diffusion (RED) could be employed to reduce the dose required to completely disorder a SL by ion implanation. Metalorganic chemical vapor deposition grown GaAs-AlAs SLs were implanted with 0.75 MeV Kr to a dose of 2×1016 cm−2 at various sample temperatures ranging from 133 K to 523 K. The extent of disordering induced by the irradiations was determined by Rutherford backscattering spectrometry and secondary ion mass spectrometry. For low temperature irradiations (133 K to 233 K), complete intermixing of the SL is observed. However, the extent of intermixing of the SL decreases with increasing specimen temperature between room temperature and 523 K. We propose two possible explanations to interpret these results: (i) that the amount of ion beam mixing decreases with increasing temperature; and (ii) that the RED coefficient is negative which suggests the existence of a miscibility gap in the GaAs-AlAs SL system.

scholarly journals Growth and Device Performance of GaN Schottky Rectifiers

1999 ◽  
Vol 4 (1) ◽  
Author(s):  
Jen-Inn Chyi ◽  
C. -M. Lee ◽  
C.C. Chuo ◽  
G. C. Chi ◽  
G. T. Dang ◽  
...  
Keyword(s):  
Breakdown Voltage ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Vapor ◽  
Negative Temperature ◽  
Organic Chemical ◽  
Schottky Rectifiers ◽  
Metal Organic ◽  
Increasing Temperature ◽  
Organic Chemical Vapor Deposition ◽  
Secondary Ion

Undoped, 4µm thick GaN layers grown by Metal Organic Chemical Vapor Deposition were used for fabrication of high stand off voltage (356 V) Schottky diode rectifiers. The figure of merit VRB2/RON, where VRB is the reverse breakdown voltage and RON is the on-resistance, was ~ 4.53 MW-cm−2 at 25°C. The reverse breakdown voltage displayed a negative temperature coefficient, due to an increase in carrier concentration with increasing temperature. Secondary Ion Mass Spectrometry measurements showed that Si and O were the most predominant electrically active impurities present in the GaN.

Calibration Method for Elemental Quantification

2000 ◽  
Vol 6 (S2) ◽  
pp. 536-537
Author(s):  
C. B. Vartuli ◽  
F. A. Stevie ◽  
L. A. Giannuzzi ◽  
T. L. Shofner ◽  
B. M. Purcell ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Peak Concentration ◽  
Energy Dispersive Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Rutherford Backscattering Spectrometry ◽  
Calibration Method ◽  
High Dose ◽  
High Concentration ◽  
Borophosphosilicate Glass ◽  
Secondary Ion

Energy Dispersive Spectrometry (EDS) is generally calibrated for quantification using elemental standards. This can introduce errors when quantifying non-elemental samples and does not provide an accurate detection limit. In addition, variations between analysis tools can lead to values that differ considerably, especially for trace elements. By creating a standard with an exact trace composition, many of the errors inherent in EDS quantification measurements can be eliminated.The standards are created by high dose ion implantation. For ions implanted into silicon, a dose of 1E16 cm-2 results in a peak concentration of approximately 1E21 cm-3 or 2% atomic. The exact concentration can be determined using other methods, such as Rutherford Backscattering Spectrometry (RBS) or Secondary Ion Mass Spectrometry (SIMS). For this study, SIMS analyses were made using a CAMECA IMS-6f magnetic sector. Measurement protocols were used that were developed for high concentration measurements, such as B and P in borophosphosilicate glass (BPSG).

Effects of Concurrent Co or Ti Silicidation on Transient Diffusion and End-of-Range Damage in Phosphorus Implanted Silicon

1992 ◽  
Vol 262 ◽  
Author(s):  
J.W. Honeycutt ◽  
J. Ravi ◽  
G. A. Rozgonyi
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Complete Removal ◽  
Dislocation Loops ◽  
Enhanced Diffusion ◽  
Depth Profiles ◽  
Enhanced Dissolution ◽  
Implantation Damage ◽  
Transmission Electron ◽  
Defect Behavior ◽  
Secondary Ion

ABSTRACTThe effects of Ti and Co silicidation on P+ ion implantation damage in Si have been investigated. After silicidation of unannealed 40 keV, 2×1015 cm-2 P+ implanted junctions by rapid thermal annealing at 900°C for 10–300 seconds, secondary ion mass spectrometry depth profiles of phosphorus in suicided and non-silicided junctions were compared. While non-silicided and TiSi2 suicided junctions exhibited equal amounts of transient enhanced diffusion behavior, the junction depths under COSi2 were significantly shallower. End-of-range interstitial dislocation loops in the same suicided and non-silicided junctions were studied by planview transmission electron microscopy. The loops were found to be stable after 900°C, 5 minute annealing in non-silicided material, and their formation was only slightly effected by TiSi2 or COSi2 silicidation. However, enhanced dissolution of the loops was observed under both TiSi2 and COSi2, with essentially complete removal of the defects under COSi2 after 5 minutes at 900°C. The observed diffusion and defect behavior strongly suggest that implantation damage induced excess interstitial concentrations are significantly reduced by the formation and presence of COSi2, and to a lesser extent by TiSi2. The observed time-dependent defect removal under the suicide films suggests that vacancy injection and/or interstitial absorption by the suicide film continues long after the suicide chemical reaction is complete.

Chromium implantation in silica glass

1996 ◽  
Vol 11 (1) ◽  
pp. 229-235 ◽  
Author(s):  
E. Cattaruzza ◽  
R. Bertoncello ◽  
F. Trivillin ◽  
P. Mazzoldi ◽  
G. Battaglin ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Photoelectron Spectroscopy ◽  
Silica Glass ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Secondary Ion Mass Spectrometry ◽  
Rutherford Backscattering Spectrometry ◽  
X Ray ◽  
Chromium Silicide ◽  
Secondary Ion

Silica glass was implanted with chromium at the energy of 35 and 160 keV and at fluences varying from 1 × 1016 to 11 × 1016 ions cm−2. In a set of chromium-implanted samples significant amounts of carbon were detected. Samples were characterized by x-ray photoelectron spectroscopy, x-ray-excited Auger electron spectroscopy, secondary ion mass spectrometry, and Rutherford backscattering spectrometry. Chromium silicide and chromium oxide compounds were observed; the presence of carbon in the implanted layers induces the further formation of chromium carbide species. Thermodynamic considerations applied to the investigated systems supply indications in agreement with the experimental evidences.

Effects of As Doping on Properties of ZnO Films

2001 ◽  
Vol 692 ◽  
Author(s):  
K. S. Huh ◽  
D. K. Hwang ◽  
K. H. Bang ◽  
M. K. Hong ◽  
D. H. Lee ◽  
...  
Keyword(s):  
Optical Properties ◽  
Secondary Ion Mass Spectrometry ◽  
Annealing Treatment ◽  
Zno Films ◽  
X Ray Diffraction ◽  
Electrical And Optical Properties ◽  
As Doping ◽  
Dopant Atoms ◽  
Increasing Temperature ◽  
Secondary Ion

AbstractA series of ZnO thin films with various deposition temperatures were prepared on (100) GaAs substrates by radio-frequency magnetron sputtering using ZnO target. The ZnO films were studied by field emission scanning electron microscope(FESEM), x-ray diffraction(XRD), photoluminescence(PL), cathodoluminescence(CL), and Hall measurements. The structural, optical, and electrical properties of the films were discussed as a function of the deposition temperature. With increasing temperature, the compressive stress in the films was released and their crystalline and optical properties were improved. From the depth profile of As measured by secondary ion mass spectrometry(SIMS), As doping was confirmed, and, in order to activate As dopant atoms, post-annealing treatment was performed. After annealing treatment, electrical and optical properties of the films were changed.

Te Induced AlAs/GaAs Superlattice Mixing

1988 ◽  
Vol 126 ◽  
Author(s):  
P. Mel ◽  
S. A. Schwarz ◽  
T. Venkatesan ◽  
C. L. Schwartz ◽  
E. Colas
Keyword(s):  
Mass Spectrometry ◽  
Activation Energy ◽  
Diffusion Coefficient ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Vapor ◽  
Temperature Range ◽  
The Relationship ◽  
Secondary Ion

ABSTRACTTe enhanced mixing of AlAs/GaAs superlattice has been observed by secondary ion mass spectrometry. The superlattice sample was grown by organometallic chemical vapor deposition and doped with Te at concentrations of 2×1017 to 5×1018 cm−.3 In the temperature range from 700 to 1000 C, a single activation energy for the Al diffusion of 2.9 eV was observed. Furthermore, it has been found that the relationship between the Al diffusion coefficient and Te concentration is linear. Comparisons have been made between Si and Te induced superlattice mixing.

scholarly journals Measurements of the Diffusion of Iron and Carbon in Single Crystal NiAl using Ion Implantation and Secondary Ion Mass Spectrometry

1998 ◽  
Vol 527 ◽  
Author(s):  
R. J. Hanrahan ◽  
S. P. Withrow ◽  
M. Puga-Lambers
Keyword(s):  
Mass Spectrometry ◽  
Ion Implantation ◽  
Single Crystal ◽  
Secondary Ion Mass Spectrometry ◽  
Tracer Diffusion ◽  
Dynamic Strain ◽  
Enhanced Diffusion ◽  
Ion Mass Spectrometry ◽  
Impurity Elements ◽  
Secondary Ion

ABSTRACTClassical diffusion measurements in intermetallic compounds are often complicated by low diffusivities or low solubilities of the elements of interest. Using secondary ion mass spectrometry for measurements over a relatively shallow spatial range may be used to solve the problem of low diffusivity. In order to simultaneously obtain measurements on important impurity elements with low solubilities we have used ion implantation to supersaturate a narrow layer near the surface. Single crystal NiAl was implanted with either 12C or both 56Fe and 12C in order to investigate the measurement of substitutional (Fe) versus interstitial (C) tracer diffusion and the cross effect of both substitutional and interstitial diffusion. When C alone was implanted negligible diffusion was observed over the range of times and temperatures investigated. When both Fe and C were implanted together significantly enhanced diffusion of the C was observed, which is apparently associated with the movement of Fe. This supports one theory of dynamic strain aging in Fe alloyed NiAl.

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