Simultaneous Implant Activation and Isolation Formation in GaAs in a Single High-Temperature Anneal

1992 ◽  
Vol 262 ◽  
Author(s):  
Kei-Yu Ko ◽  
S. Chen ◽  
G. Braunstein ◽  
L.-R. Zheng ◽  
S.-T. Lee
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
High Temperatures ◽  
Active Regions ◽  
High Resistivity ◽  
Thermally Stable ◽  
Electrical Isolation ◽  
Device Processing ◽  
High Temperature Anneal ◽  
Thermal Stability Of

ABSTRACTUsing void-related compensation in Al-implanted GaAs, high-resistivity isolation regions that are thermally stable to high temperatures (> 700 °C) are demonstrated. The high-temperature thermal stability of the isolation regions allows the simplification of device processing in which a single high-temperature anneal (e.g., at 900 °C) can be used to activate the implant dopants in the device-active regions, and simultaneously to convert the Al-implanted regions highly resistive for electrical isolation. Other advantages of using void-related isolation will also be discussed.

scholarly journals The Thermal Stability of the Naphthalene Sulfonic Acids Under Geothermal Conditions

2021 ◽  
Author(s):  
◽  
Lucjan Sajkowski
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
High Temperatures ◽  
Solid Phase ◽  
Atmospheric Oxygen ◽  
Pure Water ◽  
Pressure Vessels ◽  
Geothermal Reservoirs ◽  
Flow Through ◽  
Thermal Stability Of

<p>A primary goal of this thesis was to obtain kinetic data on the breakdown and isomerisation reactions of naphthalene disulfonate (NDS) and naphthalene sulfonate (NSA) compounds under geothermal conditions. A secondary aim of this study was to investigate NDS/NSA isomerisation transformations as well as to study their kinetics and identify products of thermal disproportionation. Because of their apparent thermal stability, naphthalene disulfonate solutions have been frequently injected into active geothermal reservoirs and their subsequent detection (“recovery”) in nearby wells/bore holes used as an indicator of well connectivity and local permeability. The results obtained in this thesis will enable a more insightful interpretation of field injection results and fluid flow in active geothermal reservoirs. The studies presented in this thesis were designed to determine the thermal stability of aqueous NDS and NSA at high temperatures from 100 to 400°C in pure water and different salt solutions (i.e. NaCl +/- Na2SO4 and Na2S) at saturated vapour pressure. The stabilities and isomerisation transformations of NDS and NSA were also studied in the presence of solid materials (i.e. quartz, greywacke, pumice) which may occur in the host geological environment of hydrothermal/geothermal reservoirs in the Earth’s crust. Dilute aqueous solutions of NDS and NSA were contained in sealed silica glass ampoules (purged of atmospheric oxygen) and placed in stainless steel pressure vessels and heated for varying times to the desired high temperatures. Additional experiments were also conducted in which dilute NDS and NSA solutions were pumped from a de-oxygenated reservoir container through a flow-through autoclave containing different rock and mineral phases at temperatures up 400°C. The resulting NDS and NSA isomers were then analysed using HPLC and GC-MS methodologies. The 1,5-naphthalene disulfonate isomer (1,5-NDS) was found to be the least stable at pHt = 3 - 8 and readily transformed to 1-naphthalene sulfonate (1-NSA) at t ≥ 200°C. The 2-NSA was found to be the most stable isomer but disappeared at t ≥ 300°. The experimental data indicated that the stabilities of all the NDS and NSA studied as a function of temperature, pH and salt (NaCl) concentration were in the sequence: 1,5-NDS < 1,6-NDS < 2,6-NDS ≈ 2,7-NDS < 2-NSA. The presence of dissolved salts was shown to slow down the decomposition rates. Results from flow-through autoclave experiments suggest that between 100 and 250°C, the stabilities of 2,6-NDS, 2,7-NDS, 1,5-NDS and 1,6-NDS are mainly controlled by solution pH, while at t ≥ 300°C, temperature is the main stability controlling factor. Additionally, no adsorption of NDS/NSA on the surface of minerals was observed. A new high-performance liquid chromatography (HPLC) method combined with solid-phase extraction (SPE) was developed to enable detection of NDS/NSA breakdown products at t ≥ 300°C. In hydrothermal solutions at temperatures greater than 300°C, all the naphthalene sulfonate isomers become unstable with the formation naphthalene (NAP) and the two naphthol isomers, 1-naphthol (1-NAP) and 2-naphthol (2-NAP), as confirmed by both the new HPLC/SPE method and GC-MS (gas chromatography–mass spectroscopy). In addition, 1-chloronaphthalene was also detected (using GC-MS) as a high temperature reaction product NDS/NSA disproportionation in 0.05 m NaCl solutions. The results of the experiments carried out during this thesis indicate that the stabilities the naphthalene mono- and disulfonates are a function of temperature, pH and salt concentration. The naphthalene sulfonates transform to different isomers and the kinetics of these isomerisation reactions have been determined. At temperatures ≥ 300°C, the NDS and NSA compounds disproportionate to the naphthalene “backbone” molecule as well as to the two stable naphthols and 1-chloronaphthalene (in chloride containing solutions). The application of naphthalene sulfonates to determine well connectivity and local permeabilities in active geothermal reservoirs is thus rather more complicated than previously appreciated. An understanding of the various isomer transformations and their kinetics is required. Furthermore, naphthalene sulfonates injected into high temperature geothermal reservoirs are unstable and breakdown to naphthalene, naphthols and probable halogenated naphthalene compounds, none of which have been considered in the interpretation of NDS/NSA recovery data in active geothermal reservoirs. The thermal stabilities of NAP, 1- and 2-NAP and 1-chloronaphthalene indicate that these compounds may also be employed as connectivity tracers in high temperature (t ≥ 300°C) systems.</p>

Implantation-Induced Voids for Thermally Stable Electrical Isolation in GaAs

1991 ◽  
Vol 240 ◽  
Author(s):  
K. Y. Ko ◽  
Samuel Chen ◽  
S. Tong ◽  
G. Braunstein
Keyword(s):  
High Temperatures ◽  
Point Defects ◽  
High Resistivity ◽  
Thermally Stable ◽  
Electrical Isolation ◽  
Isolation Techniques ◽  
Lattice Damage ◽  
High Processing

ABSTRACTMicroscopic voids, formed from the condensation of supersaturated vacancy point defects, were recently discovered in implanted and annealed GaAs. These defects have been shown to suppress carrier concentrations. Since voids are formed only at relatively high temperatures (> 650 °C), the possibility exists that voids can be used for thermally stable implant isolation. In this paper, we report on the formation of highly resistive layers in GaAs, created by Al+ implantation and annealing in the 700–900 °C range. In samples containing voids, their sheet resistivities increased by about six orders of magnitude from the as-grown value. Formation of these thermally stable, high resistivity regions is different from the conventional H or O implant isolation techniques, which use lattice damage to create the isolation characteristics. However, since lattice damage is annealed out between 400–700 °C, this type of isolation becomes ineffective at high processing temperatures. By contrast, voids are stable at high processing temperatures, and potential advantages of using such defects for device isolation in GaAs are pointed out.

Stability Improvement of Nickel Silicide with Co Interlayer on Si, Polysilicon and SiGe

2001 ◽  
Vol 670 ◽  
Author(s):  
Jer-shen Maa ◽  
Douglas J. Tweet ◽  
Yoshi Ono ◽  
Lisa Stecker ◽  
Sheng Teng Hsu
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Sheet Resistance ◽  
Nickel Silicide ◽  
Formation Temperature ◽  
Facet Structure ◽  
High Temperature Anneal ◽  
Lower Temperature ◽  
Co Addition ◽  
Thermal Stability Of

ABSTRACTThermal stability of nickel silicide is improved by adding a thin Co interlayer at Ni/Si interface. After high temperature anneal, the low sheet resistance of silicide and the low junction leakage of the ultra-shallow junction show the lack of film degradation. The transformation to disilicide phase occurred at a lower temperature. At 850°C, interface shows the truncated facet structure extended 100° to 200° below silicide/Si interface. With Co addition, nickel silicide formed on polysilicon and on SiGe films also show improved thermal stability and low sheet resistance. Formation temperature of disilicide phase occurred at lower temperature in all these cases.

The Thermal Stability of Monosulfidic Crosslinks in Natural Rubber

1983 ◽  
Vol 56 (2) ◽  
pp. 337-343 ◽  
Author(s):  
G. P. McSwkeeney ◽  
N. J. Morrison
Keyword(s):  
Thermal Stability ◽  
Stearic Acid ◽  
Natural Rubber ◽  
High Temperatures ◽  
Zinc Stearate ◽  
Thermally Stable ◽  
Thermal Stability Of

Abstract (1) Networks containing mainly monosuifidic crosslinks at methylene sites in the polyisoprene chains of natural rubber are expected to be more thermally stable than existing efficiently vulcanized networks. (2) Certain zinc-accelerator species promote the decomposition of crosslinks at high temperatures, but may be deactivated by complexation with zinc stearate (which is formed from stearic acid during vulcanization).

scholarly journals The Thermal Stability of the Naphthalene Sulfonic Acids Under Geothermal Conditions

2021 ◽  
Author(s):  
◽  
Lucjan Sajkowski
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
High Temperatures ◽  
Solid Phase ◽  
Atmospheric Oxygen ◽  
Pure Water ◽  
Pressure Vessels ◽  
Geothermal Reservoirs ◽  
Flow Through ◽  
Thermal Stability Of

<p>A primary goal of this thesis was to obtain kinetic data on the breakdown and isomerisation reactions of naphthalene disulfonate (NDS) and naphthalene sulfonate (NSA) compounds under geothermal conditions. A secondary aim of this study was to investigate NDS/NSA isomerisation transformations as well as to study their kinetics and identify products of thermal disproportionation. Because of their apparent thermal stability, naphthalene disulfonate solutions have been frequently injected into active geothermal reservoirs and their subsequent detection (“recovery”) in nearby wells/bore holes used as an indicator of well connectivity and local permeability. The results obtained in this thesis will enable a more insightful interpretation of field injection results and fluid flow in active geothermal reservoirs. The studies presented in this thesis were designed to determine the thermal stability of aqueous NDS and NSA at high temperatures from 100 to 400°C in pure water and different salt solutions (i.e. NaCl +/- Na2SO4 and Na2S) at saturated vapour pressure. The stabilities and isomerisation transformations of NDS and NSA were also studied in the presence of solid materials (i.e. quartz, greywacke, pumice) which may occur in the host geological environment of hydrothermal/geothermal reservoirs in the Earth’s crust. Dilute aqueous solutions of NDS and NSA were contained in sealed silica glass ampoules (purged of atmospheric oxygen) and placed in stainless steel pressure vessels and heated for varying times to the desired high temperatures. Additional experiments were also conducted in which dilute NDS and NSA solutions were pumped from a de-oxygenated reservoir container through a flow-through autoclave containing different rock and mineral phases at temperatures up 400°C. The resulting NDS and NSA isomers were then analysed using HPLC and GC-MS methodologies. The 1,5-naphthalene disulfonate isomer (1,5-NDS) was found to be the least stable at pHt = 3 - 8 and readily transformed to 1-naphthalene sulfonate (1-NSA) at t ≥ 200°C. The 2-NSA was found to be the most stable isomer but disappeared at t ≥ 300°. The experimental data indicated that the stabilities of all the NDS and NSA studied as a function of temperature, pH and salt (NaCl) concentration were in the sequence: 1,5-NDS < 1,6-NDS < 2,6-NDS ≈ 2,7-NDS < 2-NSA. The presence of dissolved salts was shown to slow down the decomposition rates. Results from flow-through autoclave experiments suggest that between 100 and 250°C, the stabilities of 2,6-NDS, 2,7-NDS, 1,5-NDS and 1,6-NDS are mainly controlled by solution pH, while at t ≥ 300°C, temperature is the main stability controlling factor. Additionally, no adsorption of NDS/NSA on the surface of minerals was observed. A new high-performance liquid chromatography (HPLC) method combined with solid-phase extraction (SPE) was developed to enable detection of NDS/NSA breakdown products at t ≥ 300°C. In hydrothermal solutions at temperatures greater than 300°C, all the naphthalene sulfonate isomers become unstable with the formation naphthalene (NAP) and the two naphthol isomers, 1-naphthol (1-NAP) and 2-naphthol (2-NAP), as confirmed by both the new HPLC/SPE method and GC-MS (gas chromatography–mass spectroscopy). In addition, 1-chloronaphthalene was also detected (using GC-MS) as a high temperature reaction product NDS/NSA disproportionation in 0.05 m NaCl solutions. The results of the experiments carried out during this thesis indicate that the stabilities the naphthalene mono- and disulfonates are a function of temperature, pH and salt concentration. The naphthalene sulfonates transform to different isomers and the kinetics of these isomerisation reactions have been determined. At temperatures ≥ 300°C, the NDS and NSA compounds disproportionate to the naphthalene “backbone” molecule as well as to the two stable naphthols and 1-chloronaphthalene (in chloride containing solutions). The application of naphthalene sulfonates to determine well connectivity and local permeabilities in active geothermal reservoirs is thus rather more complicated than previously appreciated. An understanding of the various isomer transformations and their kinetics is required. Furthermore, naphthalene sulfonates injected into high temperature geothermal reservoirs are unstable and breakdown to naphthalene, naphthols and probable halogenated naphthalene compounds, none of which have been considered in the interpretation of NDS/NSA recovery data in active geothermal reservoirs. The thermal stabilities of NAP, 1- and 2-NAP and 1-chloronaphthalene indicate that these compounds may also be employed as connectivity tracers in high temperature (t ≥ 300°C) systems.</p>

Formation of a Thermally Stable NiSi FUSI Gate Electrode by a Novel Integration Process

2006 ◽  
Vol 958 ◽  
Author(s):  
Shiang Yu Tan ◽  
Hsien-Chia Chiu ◽  
Chun-Yen Hu
Keyword(s):  
Thermal Stability ◽  
Electrical Properties ◽  
Process Integration ◽  
Measurement Techniques ◽  
Nickel Silicide ◽  
High Resistivity ◽  
Thermally Stable ◽  
Integration Process ◽  
Gate Electrode ◽  
Thermal Stability Of

ABSTRACTNickel silicide is promising to be the choice material as contact to the source, drain, and gate for sub-65 nm and 45 nm CMOS devices. However, the thermal stability of NiSi is worse as the high resistivity phase of NiSi2 nucleates at about 750 °C and film agglomeration occurs even at a temperature as low as 600 °C. The process integration issues and formation thermally stable NiSi are needed to be understood and addressed. In order to obtain a thermally stable Ni-FUSI gate electrode, we introduced a novel integration process by using a two-step anneal process associating with properly tuned thickness of the initial Ni film and implant BF2 atoms during the poly-gate formation. As results, push the transformation of NiSi2 to a higher temperatures at about 900 °C. Several measurement techniques such as XRD, TEM, SEM and Resistivity are carried out to demonstrate its physical and electrical properties.

Gelation Kinetics and Performance Evaluation of an Organically Crosslinked Gel at High Temperature and Pressure

SPE Journal ◽  
2008 ◽  
Vol 13 (03) ◽  
pp. 337-345 ◽  
Author(s):  
Ghaithan A. Al-Muntasheri ◽  
Hisham A. Nasr-El-Din ◽  
Pacelli L.J. Zitha
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Gelation Time ◽  
Polymer Gels ◽  
Water Production ◽  
Thermally Stable ◽  
Covalent Bonds ◽  
Pressure Drops ◽  
Gelation Kinetics ◽  
Thermal Stability Of

Summary Organically crosslinked gels have been used to control water production in high temperature applications. These chemical systems are based on the crosslinking of a polyacrylamide-based polymer/copolymer with an organic crosslinker. Polyethyleneimine (PEI) has been used as an organic crosslinker for polyacrylamide-based copolymers to provide thermally stable gels. Literature reported that PEI can form aqueous gels with polyacrylamide (PAM) at room temperature. In this paper, we show for the first time the possibility of crosslinking polyacrylamide with PEI at temperatures up to 140°C (285°F) and pressures up to 30 bars (435 psi). This paper reports data both in bulk and in porous media. The gelation time of the PAM crosslinked with PEI at high temperatures up to 140°C (285°F) and pressures up to 435 psi (30 bars) was measured. The effects of polymer concentration, crosslinker concentration, temperature, salinity, initial pH value, and the initial degree of hydrolysis of the polymer on the gelation time were examined in detail. All measurements were conducted in the steady shear mode. 13C Nuclear Magnetic Resonance Spectroscopy (13C NMR) was used to relate the gelation time to changes in the structure of the polymer and hence explain the variation in the gelation time in terms of the gelling system chemistry. In bulk, thermally stable gels were obtained by crosslinking PAM with PEI at 130°C (266°F) for at least 8 weeks. The performance of the PAM/PEI system in sandstone cores at a temperature of 90°C (194°F) and pressure drops of 68.95 bars (1,000 psi) was examined. The system was found to be stable for 3 weeks, where the permeability was reduced by a factor of 100%. Introduction Water production is a serious problem in petroleum-producing operations. Additional costs are imposed by processing, treating, and disposing unwanted water. Of the available remediation techniques, chemical methods using polymer gels have been widely applied. The success rate of these chemical treatments depends, among other factors, on the understanding of gelation kinetics, gelant's compatibility with reservoir fluids, and thermal stability of the final gel. Polymer gels have been used to reduce water production through the disproportionate permeability reduction (DPR) (Zaitoun and Kohler 1988; Liang et al. 1995). In DPR, the relative permeability to water is reduced to a greater extent than that to oil (or gas). Polymer gels were also used to totally block the pore space of the water producing zones in both matrix (Vasquez et al. 2003) and fractures (Alqam et al. 2001). Polymer gels are generally classified into two categories based on the nature of polymer/crosslinker bonding chemistry. The first type is inorganic gel systems based on the crosslinking of the carboxylate groups on the partially hydrolyzed polyacrylamide chain (PHPA) with a trivalent cation like Cr(III) (Sydansk 1990; Lockhart 1994). This crosslinking is believed to rely on coordination covalent bonding. It should be mentioned that Cr(III)-carboxylate/acrylamide-polymer gels (CC/AP) were reported to be stable at temperatures up to 148.9°C (300°F) in Berea cores under pressure drops of 68.95 bars (1,000 psi) (Sydansk and Southwell 2000). The second class of polymer gels is based on covalent bonds between the crosslinker and the acrylamide-based polymer (Morgan et al. 1998; Moradi-Araghi 2000). High temperature applications require the use of thermally stable covalently bonded systems. However, these covalent bonds do not guarantee long-term stability. Literature reports (Moradi-Araghi 2000) highlight the importance of using a thermally stable polymer to produce thermally stable gels. Polyacrylamide-based polymers are known to hydrolyze at high temperatures causing gel syneresis (expulsion of water out of the gel structure due to over crosslinking) (Moradi-Araghi 2000), especially in brines with high contents of Mg+2 and Ca+2, where polymer precipitation may also occur (Moradi-Araghi and Doe 1984). Therefore, more thermally stable monomers are copolymerized with the acrylamide polymer to minimize excessive hydrolysis (Moradi-Araghi et al. 1987; Doe et al. 1987) and enhance thermal stability of the produced gel.

High-Temperature Dielectric Materials from Atomically-Thin Perovskites

2016 ◽  
Vol 2016 (CICMT) ◽  
pp. 000164-000168
Author(s):  
Minoru Osada ◽  
Takayoshi Sasaki
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
High Temperatures ◽  
Electronic Materials ◽  
Dielectric Materials ◽  
Layered Compound ◽  
Layer By Layer ◽  
High K ◽  
Thermal Stability Of

Abstract The search of new electronic materials for high-temperature applications has been a significant challenge in recent years. In automotive industries, for example, cutting-edge technology requires electronic components operable at high temperatures (&gt; 200 °C). The absence of suitable capacitors is one of the major barriers to meet this goal. Here we provide a solution to these issues by using an atomically-thin perovskite nanosheet (Ca2Nb3O10), a two-dimensional material derived from the exfoliation of a layered compound. Through in-situ characterizations, we found a robust thermal stability of Ca2Nb3O10 nanosheet even in a monolayer form (~ 2 nm). Furthermore, layer-by-layer assembled nanocapacitors retained both size-free high-εr characteristic and high insulation resistance at high temperatures up to 250 °C. The simultaneous improvement of εr and thermal stability in high-k nanodielectrics is of critical technological importance for the use of high-temperature capacitors.

Nickel nanoparticles individually encapsulated in densified ceramic shells for thermally stable solar energy absorption

2019 ◽  
Vol 7 (7) ◽  
pp. 3039-3045 ◽  
Author(s):  
Dawei Ding ◽  
Kai Liu ◽  
Qikui Fan ◽  
Bitao Dong ◽  
Yang Zhang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Solar Energy ◽  
Energy Absorption ◽  
Nickel Nanoparticles ◽  
Thermal Conversion ◽  
Solar Thermal ◽  
Thermally Stable ◽  
Spectrally Selective ◽  
Thermal Stability Of

Encapsulation of nickel nanoparticles in densified silica nanoshells enhances the thermal stability of spectrally selective absorbers for high-temperature solar-thermal conversion systems.

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