Ion Implantation Monitoring of GaAs Using Thermal Waves

1993 ◽  
Vol 316 ◽  
Author(s):  
R. Garcia ◽  
E. J. Jaquez ◽  
R.J. Culbertson ◽  
C. D'Acosta ◽  
C. Jasper
Keyword(s):  
Activation Energy ◽  
Thermal Properties ◽  
Ion Implantation ◽  
Diffusion Process ◽  
Thermal Wave ◽  
Room Temperature ◽  
Implantation Dose ◽  
Thermal Waves ◽  
Crystal Imperfections ◽  
Logarithmic Decay

ABSTRACTLaser modulated thermoreflectivity, also called thermal wave technology, has been used in recent years to monitor ion implantation dose by monitoring the damage due to implantation. The thermal properties which are affected by lattice perturbations and other crystal imperfections are tracked by this technique. A gauge capability study was performed on the Thermawave TP300 for monitoring ion implantation of GaAs wafers. The results are presented. In order to determine the sensitivity of the technique to changes in dose, a matrix of GaAs and Si wafers was measured. During this study a downward trend was observed in the repeatability of our results. It is shown that damage to a sample during implantation will relax to a certain degree at room temperature. This damage relaxation can take up to 80 hours at room temperature and can be observed using thermal waves. It is shown that “hot wafer decay” follows a logarithmic decay which is indicative of a diffusion process. At 180°C the decay lasts less than 1 minute which indicates that the defects causing this phenomenon have a low activation energy.

Effects of the Subsequent Ion Irradiation on the Formation Process of β-SiC from Si-C Mixtures Fabricated on Si by Ion Implantation

1987 ◽  
Vol 97 ◽  
Author(s):  
Tadamasa Kimura ◽  
Hiroyuki Yamaguchi ◽  
Shigemi Yugo ◽  
Yoshio Adachi
Keyword(s):  
Activation Energy ◽  
Ion Implantation ◽  
Infrared Absorption ◽  
Formation Process ◽  
Room Temperature ◽  
Ion Irradiation ◽  
Infrared Absorption Spectroscopy ◽  
Energetic Ions ◽  
Mixed Layers ◽  
Post Implantation

ABSTRACTThe β-SiC formation process through post-implantation annealing of Si-C mixtures fabricated on Si by C-ion implantation at room temperature is studied by means of infrared absorption spectroscopy. It is shown that the formation of B-SiC from the Si-C mixtures is greatly enhanced by the subsequent irradiation of other energetic ions prior to the thermal annealing. The continuous amorphization of the Si-C mixed layers is considered to be the dominant cause for the enhancement of the B-SiC formation. The activation energy of the β-SiC formation process which is 5.3 eV without irradiation is reduced to 4.0 eV by the irradiation of 150 keV, 1 × 1017/cm2 Ar ions.

GaN P-N Structures Fabricated by Mg ION Implantation

1998 ◽  
Vol 537 ◽  
Author(s):  
E.V. Kalinina ◽  
V.A. Solov'ev ◽  
A.S. Zubrilov ◽  
V.A. Dmitriev ◽  
A.P. Kovarsky
Keyword(s):  
Ion Implantation ◽  
Room Temperature ◽  
Implantation Dose ◽  
Electrical Characteristics ◽  
Scattered Electron ◽  
Current Voltage ◽  
Capacitance Voltage ◽  
Electron Beam Induced Current ◽  
P Type ◽  
Secondary Ion

AbstractIn this paper we report on the first GaN p-n diodes fabricated by Mg ion implantation doping of n-type GaN epitaxial layers. Ion implantation was performed at room temperature. Implantation dose ranged from 1013 to 2 × 1016 cm2. After implantation samples were annealed for 10-15 s at a wide temperature interval from 600°C to 1200°C in flowing N2 to form p-type layers. Secondary ion mass spectroscopy, scanning electron microscopy with electron beam induced current and back scattered electron modes as well as current-voltage and capacitance-voltage measurements were used to study structural and electrical characteristics of the Mg implanted p-n structures.

Formation and Effects of Secondary Defects in Ion implanted Silicon

1980 ◽  
Vol 2 ◽  
Author(s):  
Jack Washburn
Keyword(s):  
Activation Energy ◽  
Electron Microscope ◽  
Low Temperature ◽  
Ion Implantation ◽  
Room Temperature ◽  
Laser Annealing ◽  
Subsequent Annealing ◽  
Interface Migration ◽  
Kinetics Of ◽  
Ion Implanted

ABSTRACTThe clustering of isolated interstitial silicon, implanted atoms, and vacant lattice sites produced by low temperature and room temperature ion implantation during subsequent annealing is reviewed. An electron microscope method for studying the kinetics of the amorphous to crystalline transformation in silicon is described. The technique is applied to measurement of the activation energy for interface migration and the formation of microtwins for different growth directions. A very brief review of the effects of laser annealing after ion implantation is included.

Measuring the Changes in InP Morphological and Electrical Specifications Caused by Oxygen Ion Implantation

2011 ◽  
Vol 264-265 ◽  
pp. 1312-1317
Author(s):  
A.H. Ramezani ◽  
M.R. Hantezadeh ◽  
M. Ghoranneviss ◽  
A.H. Sari
Keyword(s):  
Surface Roughness ◽  
Ion Implantation ◽  
Room Temperature ◽  
Implantation Dose ◽  
Force Microscopy ◽  
Oxygen Ions ◽  
Oxygen Ion ◽  
Atomic Force ◽  
Before And After ◽  
Oxygen Ion Implantation

This paper is the results of oxygen ion implantation on morphological and electrical properties of indium phosphate (InP) semiconductor wafers. The oxygen ions were implanted at 30 keV and various doses in the range between 5×10 15 to 5×10 17 ions/cm2 and at nearly room temperature. The changes in surface roughness and resistivity before and after the implantation is studied using atomic force microscopy (AFM) and four-point probes technique, respectively. The results show that the resistivity is depend on the ion implantation dose. In addition, the RMS roughness of implanted samples dramatically increases by accumulation of oxygen ion dose.

Thermal wave imaging of microelectronics

2016 ◽  
Vol 138 (2) ◽  
Author(s):  
Miguel Goni ◽  
Aaron J. Schmidt
Keyword(s):  
Thermal Properties ◽  
Surface Temperature ◽  
Thermal Wave ◽  
High Frequency ◽  
Low Frequency ◽  
Thermal Response ◽  
Glass Layer ◽  
Thermal Waves ◽  
Frequency Wave ◽  
Thermal Penetration Depth

Thermal waves can reveal thermal properties of different layers forming a multilayer structure. If the thickness of each layer is known, specific ranges of thermal wave frequencies can be implemented to study the thermal response of a specific number of layers and eventually extract the thermal properties of individual layers. As a first approach this idea can be simplified by means of the thermal penetration depth parameter, δ. The thermal penetration depth is defined as, δ=k/πCf, where k and C are respectively the thermal conductivity and volumetric heat capacity of the material carrying the thermal wave and f is the frequency of the thermal wave. From this expression it can be seen how it is possible to constrain the material thermal response to a desired depth by controlling the frequency. Thus, using high enough frequencies, the top layer properties would be measured first. Decreasing the thermal wave frequency by an appropriate amount would include the next layer in the thermal response. Since the properties of the first layer are now known, it would be possible to extract the properties of the current layer. The measurement would continue in a similar fashion for the remaining layers. Frequency domain thermoreflectance (FDTR) can be used to generate thermal waves. In this technique, a periodically modulated continuous wave laser (red pump beam) provides the periodic heat flux input into the material while a second laser (green probe beam) monitors the surface temperature through a proportional change of the surface reflectivity. The measured value is the phase lag (degrees) between the incoming thermal wave and the surface temperature response. In this study, an FDTR system was used in conjunction with a piezo stage to obtain thermal images of two different multilayer structures. The first one consisted of a CPU chip formed mainly by layers of SiO2 and Cu. The second case consisted of a TFT LCD screen from a mobile device. Regarding the CPU chip, the low frequency thermal wave travelled well past the second layer of Cu wires and provided thermal information about the bottom layers of the chip. In contrast, the high frequency wave could not penetrate through the second layer, which resulted in a more sensitive response upon the Cu wires close to the surface. A similar phenomenon occurred with the LCD screen. In this case the top layer was a glass layer used to sandwich the liquid crystal and the second layer is composed of the ITO electrodes that provide the electric field. It can be observed how the high frequency wave did not penetrate through the top glass layer providing no thermal information about the bottom layer as opposed to the low frequency wave, which clearly shows the ITO electrodes. The estimated thermal penetration depths displayed on top of each image were calculated using the equation provided before with known thermal properties of SiO2, Cu and ITO.

scholarly journals GaN p-n Structures Fabricated by Mg Ion Implantation

1999 ◽  
Vol 4 (S1) ◽  
pp. 751-756 ◽  
Author(s):  
E.V. Kalinina ◽  
V.A. Solov’ev ◽  
A.S. Zubrilov ◽  
V.A. Dmitriev ◽  
A.P. Kovarsky
Keyword(s):  
Ion Implantation ◽  
Room Temperature ◽  
Implantation Dose ◽  
Electrical Characteristics ◽  
Scattered Electron ◽  
Current Voltage ◽  
Capacitance Voltage ◽  
Electron Beam Induced Current ◽  
P Type ◽  
Secondary Ion

AbstractIn this paper we report on the first GaN p-n diodes fabricated by Mg ion implantation doping of n-type GaN epitaxial layers. Ion implantation was performed at room temperature. Implantation dose ranged from 1013 to 2×1016 cm−2. After implantation samples were annealed for 10-15 s at a wide temperature interval from 600°C to 1200°C in flowing N2 to form p-type layers. Secondary ion mass spectroscopy, scanning electron microscopy with electron beam induced current and back scattered electron modes as well as current-voltage and capacitance-voltage measurements were used to study structural and electrical characteristics of the Mg implanted p-n structures.

Photothermal examination of buried layers

1986 ◽  
Vol 64 (9) ◽  
pp. 1291-1292 ◽  
Author(s):  
J. Baumann ◽  
R. Tilgner
Keyword(s):  
Thermal Properties ◽  
Heat Source ◽  
Thermal Wave ◽  
Diffusion Length ◽  
Thermal Waves ◽  
Layer Sample ◽  
Buried Layer ◽  
Buried Layers ◽  
Periodic Illumination

The influence of a buried layer within a sample on the propagation of thermal waves is determined by measuring the phase and amplitude of the photothermal signal during periodic illumination. The results are in agreement with the calculation that follows a thermal-wave approach involving a three-layer sample and a Lambert–Beer-like distribution of the heat source in the covering layer. In this way determination of the thickness or thermal properties of buried layers even much thinner than their thermal-diffusion length is possible.

scholarly journals In-Situ and Ion Implantation Nitrogen Doping on Near Stoichiometric a-SiC:H Films

2004 ◽  
Vol 1 (2) ◽  
pp. 26-30
Author(s):  
A. R. Oliveira ◽  
M. N. P. Carreño
Keyword(s):  
Activation Energy ◽  
Electrical Conductivity ◽  
Ion Implantation ◽  
Nitrogen Doping ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Dark Conductivity ◽  
Implantation Technique ◽  
Electrical Conductivities

In this work we study the nitrogen n-type electrical doping of a-Si0.5C0.5:H films obtained by plasma enhanced chemical vapor deposition (PECVD) utilizing and comparing two doping techniques: in-situ (during the material growth) and ion implantation. The in-situ doped a-SiC:H films were obtained adding different amounts of N2 to the precursor gas mixture. For ion implantation four different nitrogen implanted concentrations were studied (between 1018 and 1021 atoms/ cm3) using multiple energies and doses to define a homogeneously doped layer. The doping experiments are carried out on a-SiC:H samples that present different structural order. The results show that high levels of electrical conductivity can be obtained with ion implantation technique. For in-situ technique the doping effect is also observed but must be improved in order to attain higher electrical conductivities. In the best case the room temperature dark conductivity for the sample implanted with 1021 nitrogens/cm3 was ~10-7 (Ω.cm)-1 and the activation energy was 0.2 eV. For in-situ doping the electrical dark conductivity reached values near 10-10 (Ω.cm)-1 at high temperatures and the activation energy was ~0.6 eV. Despite of the apparent low values of the electrical conductivity, these results are promising because we are dealing with a wide gap material and the doping processes are still not optimized.

On the use of Ozawa/Flynn/Wall method to determine aging activation energy for elastomers

2021 ◽  
pp. 009524432110203
Author(s):  
Sudhir Bafna
Keyword(s):  
Mechanical Properties ◽  
Activation Energy ◽  
Weight Loss ◽  
Oxygen Consumption ◽  
Dwell Time ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Degradation Mechanism ◽  
Kinetics Of ◽  
Wall Method

It is often necessary to assess the effect of aging at room temperature over years/decades for hardware containing elastomeric components such as oring seals or shock isolators. In order to determine this effect, accelerated oven aging at elevated temperatures is pursued. When doing so, it is vital that the degradation mechanism still be representative of that prevalent at room temperature. This places an upper limit on the elevated oven temperature, which in turn, increases the dwell time in the oven. As a result, the oven dwell time can run into months, if not years, something that is not realistically feasible due to resource/schedule constraints in industry. Measuring activation energy (Ea) of elastomer aging by test methods such as tensile strength or elongation, compression set, modulus, oxygen consumption, etc. is expensive and time consuming. Use of kinetics of weight loss by ThermoGravimetric Analysis (TGA) using the Ozawa/Flynn/Wall method per ASTM E1641 is an attractive option (especially due to the availability of commercial instrumentation with software to make the required measurements and calculations) and is widely used. There is no fundamental scientific reason why the kinetics of weight loss at elevated temperatures should correlate to the kinetics of loss of mechanical properties over years/decades at room temperature. Ea obtained by high temperature weight loss is almost always significantly higher than that obtained by measurements of mechanical properties or oxygen consumption over extended periods at much lower temperatures. In this paper, data on five different elastomer types (butyl, nitrile, EPDM, polychloroprene and fluorocarbon) are presented to prove that point. Thus, use of Ea determined by weight loss by TGA tends to give unrealistically high values, which in turn, will lead to incorrectly high predictions of storage life at room temperature.

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