DLTS studies of defects produced in n-type silicon by hydrogen implantation at low temperature

2002 ◽  
Vol 744 ◽  
Author(s):  
Takahide Sugiyama ◽  
Masayasu Ishiko ◽  
Shigeki Kanazawa ◽  
Yutaka Tokuda
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Room Temperature ◽  
Reverse Bias ◽  
Thermal Emission ◽  
Sample Temperature ◽  
Zero Bias ◽  
Type Silicon ◽  
Projected Range ◽  
Hydrogen Implantation

ABSTRACTMetastable defects are discovered in hydrogen-implanted n-type silicon. Hydrogen implantation was performed with the energy of 80 keV to a dose of 2×10 cm- at 109 K. After implantation, the sample temperature was raised to room temperature. DLTS measurements were carried out in the temperature range 80–290 K for fabricated diodes. When the sample is reverse-biased at 10V for 10 min at room temperature and then is cooled down to 80 K, three new peaks labeled EM1, EM2 and EM3 appear around 150, 190 and 240 K, respectively. The introduction of metastable defects is found to be characteristic of low temperature implantation. We have evaluated properties of EM1 in detail. EM1 with thermal emission activation energy of 0.29 eV has a peak in concentration around the depth of 0.64 μ m, which corresponds to the projected range of 80 keV hydrogen. EM1 is regenerated with the reverse bias applied around 270 K and is removed with the zero bias around 220 K.

Layer Transfer of Hydrogen-Implanted Silicon Wafers by Thermal-Microwave Co-Activation

2006 ◽  
Vol 913 ◽  
Author(s):  
Y. Y. Yang ◽  
C. H. Huang ◽  
Y. -K. Hsu ◽  
S. -J. Jeng ◽  
C. -C. Tai ◽  
...  
Keyword(s):  
Thin Film ◽  
Low Temperature ◽  
Silicon On Insulator ◽  
Hydrogen Ions ◽  
Silicon Thin Film ◽  
Projected Range ◽  
Hydrogen Molecules ◽  
Bonded Interface ◽  
Hydrogen Implantation ◽  
Short Time

AbstractSilicon on insulator (SOI) substrate is a key materials for nano-scaling IC device and the requirement for its crystal structure and quality is really high. Nanothick silicon thin film can be transferred onto a handle wafer from a donation wafer to form a SOI wafer after this process including hydrogen implantation of donation wafer, wafer bonding, and thermal treatment at moderately high temperatures of 400 to 600 degree centigrade. The expansion of the hydrogen molecular evolving from the implanted hydrogen ions interacting with silicon dangling bonds and trapped inside the microcavities located near the ion projected range resulted in exfoliation of the silicon thin film in the final heating step. The hydrogen molecules inside the microcavities tend to expand along the bonded interface rather than radially to form individual blisters. Finally, the fracture failure of ion implanted area parallel to the bonded interface near the projected ion range is formed by the sideway expansion of the cavities due to the diffusion supply of implanted hydrogen excited by thermal energy. Microwave processing can lower the activity energy to speed the chemical reaction so that it leads the format of microcavities occurring at low temperature by directly exciting the implanted hydrogen ions by microwave energy and also results in decreasing the critical dosage for layer splitting. However, microwave irradiation alone at room temperature causes the formation of lots of nucleus sites of micro-voids filled by hydrogen molecule which is immobility in silicon resulting in the issue of uniformity of transferred layer. In this study, the hydrogen implanted silicon substrate was irradiated by microwave at low temperature (200 degree centigrade) rather than microwave alone to co-activate the implanted hydrogen ions in silicon to increase not only kinetic energy but also mobility to successfully achieve a completely transferred layer in a short time.

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.

Formation of NiSi-Silicided p + n Shallow Junctions Using Implant Through Silicide and Low Temperature Furnace Annealing

2003 ◽  
Vol 765 ◽  
Author(s):  
Chao-Chun Wang ◽  
Chiao-Ju Lin ◽  
Mao-Chieh Chen
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Thermal Annealing ◽  
Reverse Bias ◽  
Reverse Current ◽  
Furnace Annealing ◽  
Silicide Layer ◽  
Shallow Junctions ◽  
Higher Temperature ◽  
Temperature Furnace

AbstractNiSi-silicided p+n shallow junctions are fabricated using BF2+ implantation into/through thin NiSi silicide layer (ITS technology) followed by low temperature furnace annealing (from 550 to 800°C). The NiSi film agglomerates following a thermal annealing at 600°C, and may result in the formation of discontinuous islands at a higher temperature. The incorporation of fluorine atoms in the NiSi film can retard the formation of film agglomeration and thus improve the film's thermal stability. A forward ideality factor of about 1.02 and a reverse current density of about 1nA/cm2 can be attained for the NiSi(310Å)/p+n junctions fabricated by BF2+ implantation at 35 keV to a dose of 5×1015cm-2 followed by a 650°C thermal annealing; the junction formed is about 60nm measured from the NiSi/Si interface. Activation energy measurements show that the reverse bias junction currents are dominated by the diffusion current, indicating that most of the implanted damages can be recovered after annealing at a temperature as low as 650°C.

scholarly journals Room temperature synthesis and characterization of novel lead-free double perovskite nanocrystals with a stable and broadband emission

2021 ◽  
Vol 9 (1) ◽  
pp. 158-163
Author(s):  
Yingying Tang ◽  
Leyre Gomez ◽  
Marco van der Laan ◽  
Dolf Timmerman ◽  
Victor Sebastian ◽  
...  
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Room Temperature ◽  
Double Perovskite ◽  
Lead Free ◽  
Synthesis And Characterization ◽  
Temperature Synthesis ◽  
Perovskite Nanocrystals ◽  
Broadband Emission

We demonstrated the synthesis of ultra small and stable Cs3BiBr6 nanocrystals, ∼1.5–3 nm, via a room-temperature antisolvent method. Red-shift of bandgap was observed in low temperature PL measurements with an activation energy of ∼41 meV.

On the Diffusion Behaviour in Stressed Ni-Zr Couples

1991 ◽  
Vol 230 ◽  
Author(s):  
G. Mazzone ◽  
A. Montone ◽  
M. Vittori Antisari
Keyword(s):  
Activation Energy ◽  
Plastic Deformation ◽  
Solid State ◽  
Low Temperature ◽  
Amorphous Phase ◽  
Temperature Regime ◽  
Applied Load ◽  
Sample Temperature ◽  
Solid State Reactions ◽  
Diffusion Behaviour

AbstractSolid state reactions at the interface of bulk Ni-Zr couples have been induced at several temperatures by compressive plastic deformation. The reaction product is an amorphous phase whose thickness increases with applied load and sample temperature. In addition, similar samples have been thermally reacted in order to measure the thermal interdiffusion coefficent in the same conditions. Measurements on stressed couples show that the interdiffusion coefficent (several orders of magnitude larger than the corresponding thermal value) follows a dual regime Arrhenius behaviour. The activation energy is independent of load and of the order of 0.2 eV in the low temperature regime extending up to 550 K. A different behaviour characterized by a single value of the activation energy in the whole temperature range has been observed in thermally treated samples.

Survival of mouse blastocysts after low-temperature preservation under high pressure

2004 ◽  
Vol 52 (4) ◽  
pp. 479-487 ◽  
Author(s):  
Cs. Pribenszky ◽  
M. Molnár ◽  
S. Cseh ◽  
L. Solti
Keyword(s):  
Phase Transition ◽  
Hydrostatic Pressure ◽  
Low Temperature ◽  
High Hydrostatic Pressure ◽  
Room Temperature ◽  
Freezing Point ◽  
Significant Loss ◽  
Embryo Cryopreservation ◽  
Subzero Temperatures ◽  
Survival Capacity

Cryoinjuries are almost inevitable during the freezing of embryos. The present study examines the possibility of using high hydrostatic pressure to reduce substantially the freezing point of the embryo-holding solution, in order to preserve embryos at subzero temperatures, thus avoiding all the disadvantages of freezing. The pressure of 210 MPa lowers the phase transition temperature of water to -21°C. According to the results of this study, embryos can survive in high hydrostatic pressure environment at room temperature; the time embryos spend under pressure without significant loss in their survival could be lengthened by gradual decompression. Pressurisation at 0°C significantly reduced the survival capacity of the embryos; gradual decompression had no beneficial effect on survival at that stage. Based on the findings, the use of the phenomena is not applicable in this form, since pressure and low temperature together proved to be lethal to the embryos in these experiments. The application of hydrostatic pressure in embryo cryopreservation requires more detailed research, although the experience gained in this study can be applied usefully in different circumstances.

Pt-Pd Nanoalloy for the Unprecedented Activation of Carbon-Fluorine Bond at Low Temperature

2019 ◽  
Author(s):  
Raghu Nath Dhital ◽  
keigo nomura ◽  
Yoshinori Sato ◽  
Setsiri Haesuwannakij ◽  
Masahiro Ehara ◽  
...  
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Dft Calculations ◽  
Bond Activation ◽  
Mild Conditions ◽  
Selective Transformation ◽  
Rate Determining Step ◽  
Highly Active ◽  
Harsh Conditions ◽  
Reaction Profile

Carbon-Fluorine (C-F) bonds are considered the most inert organic functionality and their selective transformation under mild conditions remains challenging. Herein, we report a highly active Pt-Pd nanoalloy as a robust catalyst for the transformation of C-F bonds into C-H bonds at low temperature, a reaction that often required harsh conditions. The alloying of Pt with Pd is crucial to activate C-F bond. The reaction profile kinetics revealed that the major source of hydrogen in the defluorinated product is the alcoholic proton of 2-propanol, and the rate-determining step is the reduction of the metal upon transfer of the <i>beta</i>-H from 2-propanol. DFT calculations elucidated that the key step is the selective oxidative addition of the O-H bond of 2-propanol to a Pd center prior to C-F bond activation at a Pt site, which crucially reduces the activation energy of the C-F bond. Therefore, both Pt and Pd work independently but synergistically to promote the overall reaction

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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