Properties and Effects of Hydrogen in GaN

1999 ◽  
Vol 595 ◽  
Author(s):  
S.J. Pearton ◽  
H. Cho ◽  
F. Ren ◽  
J.-I. Chyi ◽  
J. Han ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Heterojunction Bipolar Transistors ◽  
Bipolar Transistors ◽  
Residual Hydrogen ◽  
Diffusion Characteristics ◽  
Significant Difference ◽  
Device Structures ◽  
The Status ◽  
The Difference ◽  
Thermal Stability Of

AbstractThe status of understanding of the behavior of hydrogen in GaN and related materials is reviewed. In particular, we discuss the amount of residual hydrogen in MOCVD-grown device structures such as heterojunction bipolar transistors, thyristors and p-i-n diodes intended for high power, high temperature applications. In these structures, the residual hydrogen originating from the growth precursors decorates Mgdoped layers and AlGaN/GaN interfaces. There is a significant difference in the diffusion characteristics and thermal stability of implanted hydrogen between n- and p-GaN, due to the stronger affinity of hydrogen to pair with acceptor dopants and possibly to the difference in H2 formation probability.

scholarly journals Properties and Effects of Hydrogen in GaN

2000 ◽  
Vol 5 (S1) ◽  
pp. 540-550 ◽  
Author(s):  
S.J. Pearton ◽  
H. Cho ◽  
F. Ren ◽  
J.-I. Chyi ◽  
J. Han ◽  
...  
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Bipolar Transistors ◽  
Residual Hydrogen ◽  
Diffusion Characteristics ◽  
Significant Difference ◽  
Device Structures ◽  
The Status ◽  
The Difference ◽  
Thermal Stability Of ◽  
Mg Doped

The status of understanding of the behavior of hydrogen in GaN and related materials is reviewed. In particular, we discuss the amount of residual hydrogen in MOCVD-grown device structures such as heterojunction bipolar transistors, thyristors and p-i-n diodes intended for high power, high temperature applications. In these structures, the residual hydrogen originating from the growth precursors decorates Mg-doped layers and AlGaN/GaN interfaces. There is a significant difference in the diffusion characteristics and thermal stability of implanted hydrogen between n- and p-GaN, due to the stronger affinity of hydrogen to pair with acceptor dopants and possibly to the difference in H2 formation probability.

Novel Multi-Finger Power HBTs with Non-Uniform Segmented Emitter for Thermal Stability Enhancement

2012 ◽  
Vol 229-231 ◽  
pp. 832-836 ◽  
Author(s):  
D.Y. Jin ◽  
D. Lu ◽  
W.R. Zhang ◽  
Q. Fu ◽  
Y.J. Zhang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Heterojunction Bipolar Transistors ◽  
Heat Dissipation ◽  
Current Density Distribution ◽  
Bipolar Transistors ◽  
Electrical Model ◽  
Collector Current ◽  
The Difference ◽  
Stability Enhancement ◽  
Thermal Stability Of

With the aid of a two-dimensional thermal-electrical model, the thermal stability of multi-finger power heterojunction bipolar transistors (HBTs) with uniform segmented emitter, and non-uniform segmented emitter are studied. It shows that both of them could lower the peak temperature and improve the non-uniformity of the collector current density distribution, and thus improve the thermal stability, compared with an HBT which has traditional non-segmented emitter structure. At the same time, the improvement capability of thermal stability for HBT with non-uniform segmented emitter is superior to that of HBT with uniform segmented emitter, ascribing to selectively divide the emitter fingers into various segments according to the difference of heat dissipation capability in emitter fingers. Furthermore, the improvement capability of thermal stability for HBT with non-uniform segmented emitter is enhanced exponentially as segment spacing increases. However, for HBT with uniform segmented emitter, the ability is less sensitive to the increasing of the segment spacing as it exceeds 6μm. Therefore, the technique of non-uniform segmented emitter is a better method for enhancing the thermal stability of power HBTs.

Characteristics of μc-Si:H for Si Heterojunction Bipolar Transistors

1989 ◽  
Vol 164 ◽  
Author(s):  
H. Fujioka ◽  
M. Ito ◽  
K. Takasaki
Keyword(s):  
Thermal Stability ◽  
Hydrogen Concentration ◽  
Heterojunction Bipolar Transistors ◽  
Bipolar Transistors ◽  
Carbon Doping ◽  
Thermally Stable ◽  
Fluorine Doping ◽  
Hydrogen Atoms ◽  
Thermal Stability Of ◽  
Crystalline Growth

AbstractTo improve the thermal stability of the Si heterojunction bipolar transistors (HBTs), we studied the effect of carbon and fluorine doping on μc-Si:H characteristics. We found that carbon doping suppresses crystalline growth and increases the hydrogen concentration in the film, and that fluorine atoms are more thermally stable than hydrogen atoms. We confirmed that carbon or fluorine doping is promising for use with the μc-Si:H HBT.

Microstructural Characterization of High-Pressure Oxidized Si1-x Gex /Si Heterolayers

1992 ◽  
Vol 280 ◽  
Author(s):  
N. David Theodore ◽  
Gordon Tam
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Atmospheric Pressure ◽  
High Pressures ◽  
Microstructural Characterization ◽  
Bipolar Transistors ◽  
Pure Silicon ◽  
Device Structures ◽  
Microstructural Behavior ◽  
Very High

ABSTRACTSiGe alloys have recently been of interest for fabrication of heterojunction bipolar transistors using pre-existing or modified silicon-processing technology. These devices are faster than devices using pure silicon. Because of the interest in developing SiGe device structures, various elements of processing relevant to fabrication of the devices are being investigated. One such element has been the use of thermal oxidation for isolation of SiGe devices. Utilization of the technique requires an understanding of oxidation behavior of SiGe layers under a variety of oxidation conditions. Past studies in the literature have investigated the oxidation of SiGe at atmospheric pressure or at very high pressures (∼650–1300 atmospheres). The present study investigates the wet-oxidation of SiGe structures at intermediate pressures (∼25 atmospheres) and temperatures (∼750°C). Unlike atmospheric oxidation, most of the Ge (from SiGe) remains in the oxidized silicon (SiO2) in the form of GeO2. Occasional segregation of Ge to the oxidizing interface is noted. The microstructural behavior of partially and entirely oxidized structures is presented.

Synthesis and Characterization of Some Functional Luminol Derivatives with Aromatic Substituted Groups

2011 ◽  
Vol 197-198 ◽  
pp. 606-609 ◽  
Author(s):  
Ti Feng Jiao ◽  
Yuan Yuan Xing ◽  
Jing Xin Zhou ◽  
Wei Wang
Keyword(s):  
Molecular Structure ◽  
Thermal Stability ◽  
Molecular Structures ◽  
Synthesis And Characterization ◽  
Functional Material ◽  
Aromatic Substituent ◽  
The Difference ◽  
Imide Group ◽  
Thermal Stability Of

Some functional luminol derivatives with aromatic substituted groups have been designed and synthesized from the reaction of the corresponding aromatic acyl chloride precursors with luminol. It has been found that depending on the size of aromatic groups, the formed luminol derivatives showed different properties, indicating distinct regulation of molecular skeletons. UV and IR data confirmed commonly the formation of imide group as well as aromatic segment in molecular structures. Thermal analysis showed that the thermal stability of luminol derivatives with p-phthaloyl segment was the highest in those derivatives. The difference of thermal stability is mainly attributed to the formation of imide group and aromatic substituent groups in molecular structure. The present results have demonstrated that the special properties of luminol derivatives can be turned by modifying molecular structures of objective compounds with proper substituted groups, which show potential application in functional material field and ECL sensor.

Characterization of Ni- and Ni(Pt)-Silicide Formation on Narrow Polycrystalline Si Lines by Raman Spectroscopy

1999 ◽  
Vol 591 ◽  
Author(s):  
P. S. Lee ◽  
D. Mangelinck ◽  
K. L. Pey ◽  
J. Ding ◽  
T. Osipowicz ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Raman Spectroscopy ◽  
Raman Mapping ◽  
Silicide Formation ◽  
Nucleation Sites ◽  
The Difference ◽  
The Stability ◽  
Non Destructive ◽  
Thermal Stability Of

ABSTRACTThe formation and thermal stability of Ni- and Ni(Pt) silicide on narrow polycrystalline Si (poly-Si) lines have been investigated using the non-destructive micro-Raman technique. The presence of Ni or Ni(Pt)Si on poly-Si lines with linewidths ranging from 0.5 gtm to 0.25 μm has been monitored by a distinct Raman peak at around 215 cm−1. Ni(Pt)Si was clearly identified to be present up to a RTA temperature of 900°C on narrow poly-Si lines as compared to pure NiSi which was found only up to 750°C. Raman scattering from the 100×100 μm2 poly-Si pads showed the formation of NiSi2 at 750°C for pure Ni-salicidation and 900°C for Ni(Pt)-salicidation respectively. The difference in the stability of NiSi on the poly-Si pads and lines is discussed in terms of agglomeration, inversion and/or nucleation of NiSi2that could be due to difference in nucleation sites and/or stress. In addition, a correlation between the line sheet resistance and the presence of Ni silicide was found using micro-Raman mapping along single poly-Si lines.

scholarly journals Synthesis and Properties of Bulk Metallic Glasses in Pd-Ni-P and Pd-Cu-P Alloys

1996 ◽  
Vol 455 ◽  
Author(s):  
Y. He ◽  
R. B. Schwarz
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Metallic Glasses ◽  
Amorphous Alloys ◽  
Composition Range ◽  
Wide Composition Range ◽  
Upper Limit ◽  
Ternary Alloy Systems ◽  
The Difference ◽  
Thermal Stability Of

ABSTRACTBulk amorphous Pd-Ni-P and Pd-Cu-P alloy rods with diameters ranging from 7 to 25 mm have been synthesized over a wide composition range using a fluxing technique. For most bulk amorphous Pd-Ni-P alloys, the difference ΔT = Tx - Tg between the crystallization temperature Tx and the glass transition temperature Tg is larger than 90 K, while for bulk amorphous Pd-Cu-P alloys, ΔT varies from 27 to 73 K. Pd40Ni40P20 has the highest glass formability, and 300-gram bulk amorphous cylinders, 25 mm in diameter and 50 mm in length, can be easily produced. This size, however, is not an upper limit. The paper presents the glass formation ranges for both ternary alloy systems and data on the thermal stability of the amorphous alloys, as well as their specific heat, density, and elastic properties.

Thermal Aging Analysis of Rubber Used for Fabric Expansion Joints

2013 ◽  
Vol 807-809 ◽  
pp. 2718-2721
Author(s):  
Li Na Ma ◽  
Yu Zeng Zhao ◽  
Hong Hua Ge ◽  
Kuai Ying Liu
Keyword(s):  
Thermal Stability ◽  
Thermal Aging ◽  
Inert Atmosphere ◽  
Expansion Joints ◽  
Chemical Structures ◽  
Before And After ◽  
The Difference ◽  
Ethylene Propylene Diene Terpolymer ◽  
Thermal Stability Of ◽  
Accelerated Thermal Aging

Several kinds of rubbers used for fabric expansion joints were studied by Thermogravimetric analysis under inert atmosphere before and after artificial accelerated thermal aging. The results showed that because of the difference of the chemical structures, the rubber aging is different. And the thermal stability of Polytetrafluoroethylene (PTFE) was obviously higher than that of other two kinds of rubbers, ethylene-propylene-diene-terpolymer rubber (EPDM) and fluororubber.

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