The Interplay of Thermo-Mechanical Properties in the Growth and Processing of III-V Materials

1991 ◽  
Vol 226 ◽  
Author(s):  
A. S. Jordan ◽  
V. Swaminathan
Keyword(s):  
Mechanical Properties ◽  
Shear Stress ◽  
Dislocation Density ◽  
Semiconductor Device ◽  
Electronic Devices ◽  
Device Fabrication ◽  
Device Performance ◽  
Bulk Crystals ◽  
Dislocation Generation ◽  
Critical Resolved Shear Stress

AbstractThe thermo-mechanical properties of III-V semiconductors, in general, and of GaAs and InP in particular, are reviewed. They play an important role in many aspects of semiconductor device fabrication starting from the growth of bulk crystals. Dislocation generation in GaAs and InP are discussed with the emphasis on the theoretical and experimental aspects of reducing the dislocation density in these materials. Such mechanical properties as glide systems, critical resolved shear stress and impurity hardening are covered. The effects of dislocations on device performance are illustrated with examples from photonic and electronic devices. Finally, the effect of thermomechanical stresses in the degradation and reliability of GaAs/AlGaAs and InP/InGaAsP based opto-electronic devices is considered.

scholarly journals Enhanced lattice distortion, yield strength, critical resolved shear stress, and improving mechanical properties of transition-metals doped CrCoNi medium entropy alloy

RSC Advances ◽  
2021 ◽  
Vol 11 (38) ◽  
pp. 23719-23724
Author(s):  
Md. Lokman Ali
Keyword(s):  
Mechanical Properties ◽  
Shear Stress ◽  
Transition Metals ◽  
Yield Strength ◽  
Lattice Distortion ◽  
Critical Resolved Shear Stress

The effect of transition-metals (TM) addition on the mechanical properties of CrCoNi medium entropy alloys (MEAs) was investigated.

Influence of Moisture-Uptake on Mechanical Properties of Polymers Used in Microelectronics

1998 ◽  
Vol 511 ◽  
Author(s):  
R. Buchhold ◽  
A. Nakladal ◽  
G. Gerlach ◽  
K. Sahre ◽  
K.-J. Eichhorn ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Polymer Films ◽  
Semiconductor Device ◽  
Mechanical Stability ◽  
Climatic Conditions ◽  
Device Fabrication ◽  
Film Stress ◽  
Moisture Uptake ◽  
Out Of Plane ◽  
The Impact

ABSTRACTPolymers are currently considered as a possible alternative to silicon dioxide in the fabrication of interlevel dielectrics. To penetrate mainstream semiconductor device fabrication polymers have to meet a number of requirements regarding their long-term stability. One aspect is the mechanical stability of integrated polymer films under changing climatic conditions. In the present work, the impact of ambient moisture on the mechanical properties of thin polymer films (PI, BCB, and PFCB) was investigated. The sorption of water molecules in these materials typically causes an anisotropic volume expansion, resulting in increased mechanical film stress if the film is physically constrained by adjacent inorganic structures. Especially polyimides show both considerable moisture uptake and large changes in the mechanical film stress, while BCB and PFCB are virtually insensitive to ambient moisture. In the paper, experimental data (water uptake, in-plane swelling, out-of-plane swelling) are presented and discussed in detail.

Impact of n-Type versus p-Type Doping on Mechanical Properties and Dislocation Evolution during SiC Crystal Growth

2007 ◽  
Vol 556-557 ◽  
pp. 259-262 ◽  
Author(s):  
Peter J. Wellmann ◽  
Philip Hens ◽  
Sakwe Aloysius Sakwe ◽  
Desirée Queren ◽  
Ralf Müller ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Crystal Growth ◽  
Dislocation Density ◽  
Basal Plane ◽  
Critical Shear Stress ◽  
Lattice Relaxation ◽  
Dislocation Generation ◽  
Basal Plane Dislocation ◽  
Donor Nitrogen ◽  
P Type

The origin of dislocation evolution during SiC crystal growth is usually related to lattice relaxation mechanisms caused by thermal stress. In this paper we discuss dislocation generation and dislocation propagation related to doping and suppression of basal plane dislocations, the latter being of particular interest for bipolar electronic devices. We have prepared alternating p-/n-/pdoped SiC crystals using the donor nitrogen and the acceptors aluminum or boron. In addition we determined the mechanical properties of n-type and p-type SiC; in particular we measured the critical shear stress by nano-indentation on c-plane and a-plane 6H-SiC surfaces. A considerably lower basal plane dislocation density is found in aluminum as well as in boron doped p-type SiC compared to nitrogen doped n-type SiC. It is concluded that the explanation of the reduced basal plane dislocation density in p-type SiC needs the consideration of electronic as well as mechanical effects.

scholarly journals Influences of Mo addition on mechanical properties and deformation behavior of β-type Ti alloys

2020 ◽  
Vol 321 ◽  
pp. 05001
Author(s):  
K. Cho ◽  
R. Morioka ◽  
H.Y. Yasuda
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Shear Stress ◽  
Tensile Properties ◽  
Deformation Behavior ◽  
Deformation Twinning ◽  
Compression Tests ◽  
Β Phase ◽  
Ti Alloys ◽  
Critical Resolved Shear Stress

The influences of Mo addition on the tensile properties and deformation behavior of β-type Ti-Mn alloys were investigated with particular focus on {332}<113> deformation twinning. We found that Ti-7Mn and Ti-5Mo-3Mo alloys exhibit completely different tensile properties, despite having the same microstructure and stability of the β phase. The Ti-5Mn-3Mo alloy demonstrates higher tensile strength and larger ductility than the Ti-7Mn alloy due to its strong work hardening, caused by {332} <113> deformation twinning. The critical resolved shear stress (CRSS) for {332}<113> deformation twinning in these alloys was measured by compression tests using single crystals. It was thereby found that Mo addition is effective in decreasing the CRSS for {332}<113> deformation twinning in Ti-Mn alloys.

Etch pit dislocation density and the critical resolved shear stress of lead

1971 ◽  
Vol 8 (1) ◽  
pp. 205-212 ◽  
Author(s):  
R. Engelen ◽  
J. van der Planken
Keyword(s):  
Shear Stress ◽  
Dislocation Density ◽  
Etch Pit ◽  
Critical Resolved Shear Stress

Microstructural evaluation of reactive ion etched - regrown GaAs

1990 ◽  
Vol 48 (4) ◽  
pp. 724-725
Author(s):  
M.W. Cole ◽  
M. Dutta ◽  
J. Rossabi ◽  
J.L. Lehman
Keyword(s):  
Quantum Well ◽  
Semiconductor Device ◽  
Microstructural Characterization ◽  
Device Fabrication ◽  
Optical Methods ◽  
Device Performance ◽  
Major Drawback ◽  
Process Step ◽  
Dry Process ◽  
Crystal Damage

Reactive ion etching (RIE) is a preferred dry process step for fabrication of submicron III-V semiconductor device structures. This kinetically assisted chemical dry etch process offers several important advantages over other etching methods, namely etch anisotropy, etch rate control, selectively, accuracy, uniformity across the wafer and reproducibility. As a result of these desirable characteristics, a number of semiconductor device designs involve REE in their device fabrication process. Some of the more novel designs involve lateral quantum well arrays, whereby fabrication requires molecular beam epitaxial (MBE) regrowth on RIE semiconductors.A major drawback of RIE is the potential lattice damage introduced by energetic ion bombardment and contamination. This material damage may lead to deterioration of device performance. It is important to identify and understand this RIE induced damage in order to develop and refine the RIE process, i.e. minimize crystal damage and thus optimize device performance. This study identifies and analyzes the damage associated with various RIE parameters used for quantum well fabrication. Microstructural characterization via TEM is used to identify the nature of lattice defects, their distribution, and density. Optical methods, Photoluminescence and Raman spectroscopy are used to evaluate the crystal damage and serve as a reliable comparators for the TEM results.

Etch Pit Dislocation Density and the Critical Resolved Shear Stress of Lead

1971 ◽  
pp. 205-212
Author(s):  
R. Engelen ◽  
J. Van Deb Planken
Keyword(s):  
Shear Stress ◽  
Dislocation Density ◽  
Etch Pit ◽  
Critical Resolved Shear Stress

Effects of Mo Addition on Deformation Behavior of Metastable Beta-Type Ti-Mn Single Crystals

2018 ◽  
Vol 941 ◽  
pp. 1360-1365 ◽  
Author(s):  
Ryota Morioka ◽  
Ken Cho ◽  
Hiroyuki Y. Yasuda
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Shear Stress ◽  
Ultimate Tensile Strength ◽  
Single Crystals ◽  
Deformation Behavior ◽  
Deformation Structures ◽  
Critical Resolved Shear Stress ◽  
Metastable Beta ◽  
First Time

In this study, to clarify the effects of Mo addition on deformation behavior of Ti-Mn alloys, the mechanical properties and the deformation structures of the alloys were investigated using Ti-Mn and Ti-Mn-Mo alloys polycrystals and single crystals. We found that the elongation of Ti-Mn alloys are improved from approximately 5% to 30% by Mo addition, with maintaining ultimate tensile strength of 900 MPa. The excellent strength-ductility balance of Ti-Mn-Mo alloys is caused by {332}<113> twinning, which is unique twinning for metastable β-type titanium alloys. Additionally, the deformation behavior of Ti-Mn and Ti-Mn-Mo alloys was investigated in detail by using single crystals focusing on a critical resolved shear stress (CRSS). As a result, we found for the first time that CRSS for {332}<113> twinning in Ti-Mn-Mo alloy was lower than that in Ti-Mn alloy. Moreover, in Ti-Mn-Mo alloy, CRSS for {332}<113> twinning was lower than that for {112}<111> slip. These results suggest that CRSS for {332}<113> twinning in Ti-Mn alloys is decreased by Mo addition.

THE EFFECT OF ORIENTATION AND IMPURITIES ON THE MECHANICAL PROPERTIES OF MOLYBDENUM SINGLE CRYSTALS

1967 ◽  
Vol 45 (2) ◽  
pp. 1063-1074 ◽  
Author(s):  
D. F. Stein
Keyword(s):  
Mechanical Properties ◽  
Shear Stress ◽  
Single Crystals ◽  
Tensile Axis ◽  
Zone Melting ◽  
Hydrogen Gas ◽  
Axis Orientation ◽  
Stereographic Triangle ◽  
Tension And Compression ◽  
Critical Resolved Shear Stress

Molybdenum single crystals containing less than 10 p.p.m. of carbon, 5 p.p.m. of nitrogen, and 5 p.p.m. of oxygen have been prepared by zone melting and hydrogen gas purification. The mechanical properties of the crystals have been measured in tension and compression over a range of temperature from 20 to 298 °K. It was found that the critical resolved shear stress and the temperature dependence of the critical resolved shear stress decreased with increasing purity. It was found that at all test temperatures the CRSS law fails. The critical resolved shear stress is a minimum in the (100) tension axis orientation and reaches a maximum with the tensile axis along the (110)(111) line of the stereographic triangle. It was also found that the ductility of molybdenum single crystals was not improved by purification.

Sign in / Sign up

Export Citation Format

Share Document