2,060,328 research outputs found
Fabrication and characterisation of novel Ge MOSFETs
No full textAs high-k dielectrics are introduced into commercial Si CMOS (Complimentary Metal Oxide Semiconductor) microelectronics, the 40 year channel/dielectric partnership of Si/SiO2 is ended and the door opened for silicon to be replaced as the active channel material in MOSFETs (Metal Oxide Semiconductor Field Effect Transistor). Germanium is a good candidate as it has higher bulk carrier mobilities than silicon. In addition, Si and Ge form a thermodynamically stable SiGe alloy of any composition, allowing Ge to be implemented as a thin layer on the surface of a standard Si substrate. This thesis is a practical investigation on several aspects of Ge CMOS technology.
High-k dielectric Ge p-MOSFETs are electrically characterised. A large variation in interface state densities is demonstrated to be responsible for a threshold voltage shift and this is proportional to reciprocal peak mobility due to the Coulomb scattering of carriers by charged states. A theoretical mobility is fitted to that measured at 4.2 K and confirms that interface states are the main source of interface charged impurities.
The model demonstrates a reduction in the interface charged impurity density in p-MOSFETs that underwent a PMA (Post Metallisation Anneal) in hydrogen atmosphere and that the anneal also reduces the RMS (Root Mean Square) dielectric/semiconductor interface roughness, from an average of 0.60 nm to 0.48 nm.
High-k strained Ge p-MOSFETs are electrically characterised and have peak mobilities at 300 K (470 cm2 V-1 s-1) and 4.2 K (1780 cm2 V-1 s-1) far in excess of those measured for the unstrained Ge p-MOSFETs (285 cm2 V-1 s-1,785 cm2 V-1 s-1 respectively). Strained Ge n-MOSFETs perform significantly worse than standard Si P, - MOSFETs primarily due to a high source/drain resistance.
A 10 nm thick SiGe-01 (On Insulator) layer with a Ge composition of 58% is obtained from a 55 nm Si0_88Ge1o2. initial layer on 100 nm Si-Ol substrate via the germanium condensation technique. For the first time, germanium is demonstrated to diffuse through the BOX (Buried OXide) during Ge-condensation and into the underlying Si substrate. An order of magnitude increase in the calculated ITOX (Internal Thermal OXidation) rate of the BOX in the final stages of Ge-condensation is hypothesised to be responsible for stopping this diffusion
Carol, Ruby and Ralph Meiling
No full textThe children of Curtis W. and Adeline Meiling are from left, Carol, Ruby and Ralph
Ge-conservación Nº26
No full textGe-conservación es una publicación periódica del GEIIC, cuyo objetivo es contribuir al desarrollo científico, a la difusión y al intercambio de los conocimientos en materia de conservación y restauración del Patrimonio Cultural
Interview of Richard L. Meiling by Robert B. Sutton
No full textPresident Novice Fawcett: (pp. 1, 3, 5, 9, 1-a, 8-a, 11-a, 14-a, 20-a) --
Senator Bricker: (p. 1) --
General Dargusch: (p. 1) --
Dr. Doan: (pp. 1, 3, 5, 29-a) --
Margaret Colburn: secretary (p. 2) -- Mrs. Frame: secretary (p. 2) --
Jake Taylor: (p. 2) --
President Bevis: (pp. 2, 11-a) --
Mr. and Mrs. Ressler: (p. 5) --
Bremmer Foundation: (p. 5) --
Dr. Wiseman: (pp. 5, 11-a, 29-a) --
President Ed Jennings: (pp. 5, 22-a) --
Dr. Greg Trzebiatowski: (p. 6) --
Dr. Lloyd Evans: (pp. 7, 8-a) --
Dr. Prior: (pp. 8, 7-a) --
John Corbally: (pp. 9, 15-a) --
Dr. Carl Caassen: (p. 10) --
Chauncey Leake: (p. 10) --
Mr. Willlet: stain glass artist (p. 10) --
James Rhodes: (pp. 11, 5-a, 11-a, 13-a, 14-a) --
Dr. Vernon Dodd: (p. 1-a) --
Al Garrett: (p. 1-a) --
Dr. Stillson: (p. 3-a) --
Dr. Strughold of Wurtzberg: (p. 3-a) --
Dr. Wattman: (p. 4-a) --
Dan Carmichael: (architect) (p. 4-a) -- John Herrick: (p. 4-a) --
Stan Meechum: (pp. 5-a, 13-a) --
Frank McClure: (p. 5-a) --
Dick Kraybaugh: (p. 5-a) --
Dr. Newton: (p. 6-a) --
Inscoe: (p. 7-a) --
Gordon Carson (p. 8-a) --
Mrs. Bevis: (p. 11-a) --
Kitty: (Pres. Bevis’s Secretary) (p. 11-a) --
Roy Kottman: (pp. 12-a, 14-a) --
Helen Rhodes: (p. 13-a) --
Harry Truman: (p. 14-a) --
Ed Moulton: (p. 16-a) --
Henry Cramblett: - (pp. 17-a, 22-a) --
Harold Enarson - pp. 20-22-a) --
Dr. Steelman: (p. 21-a) -
- General Marshal: (p. 21-a) --
Mr. Lackner: (p. 21-a) --
Mr. Sam Porter: (lawyer) (p. 22-a) --
Mr. Eiland (Asst. Attorney General): (p. 22-a) --
Dr. Tzagournis: (p. 22-a) --
Dr. Lynn: (p. 23-a) --
Dr. Burke: (p. 23-a) --
Congressman Carl Vincent: (p. 23-a) --
Dr. Curtis: (p. 29-a) --
Mrs. R. Meiling: (p. 29-a) --
Drs. Means, Hamilton, Zollinger, Copeland: (p. 29-a)Vice president Emeritus for Medical Affairs, Dean of the College of Medicine and Professor of Obstetrics and Gynecology, The Ohio State University. Includes oral history interview with Meiling from 1983. Includes correspondence, scrapbooks, biographical materials and reprints of articles; also includes oral history interview with Robert Sutton, from Nov. 1983
College of Medicine Administration Center (Meiling Hall)
No full textEntry created by John H. Herrick June 17, 1976John H. Herrick Archives: Documenting Structures at The Ohio State UniversityThe University Archives has determined that this item is of continuing value to OSU's history.College of Medicine Administration Center (Meiling Hall) is located at 370 West 9th Avenue (originally 350 West 9th Avenue). Never officially named by Board of Trustees action. Alternate names include: "Medical College Administration Building", "Medical Administration Building". Built as the Administrative Unit of the Medical Basic Science Building. The Board of Trustees on September 7, 1984 changed the name of this building to "Richard Lewis Meiling Hall.
Curtis and Adeline Meiling Family
No full textCurtis W. and Adeline Meiling are pictured with their children. Children are listed from left, Carol, Ruby and Ralph. Curtis owned Ideal Garage and also was a driver for the government star mail route
Transport properties for pure strained Ge quantum well
No full textModulation doped heterostructures consisting of a strained Ge (sGe) quantum well on a Si0.2Ge0.8 virtual substrate have been used to study enhancement of the transport properties of holes in the sGe channel due to the effective reduction of impurity scattering by placing the doping layer away from the channel.
Electrical and structural analysis was performed for sGe heterostructures produced with a range of growth parameters. The highest hole mobility was 1.34×106 cm2 /Vs at 0.5 K for a sGe quantum well in a 'normal' structure (i.e. doped above the channel) at a sheet density of 2.9×1011 cm-2, which is the largest hole mobility reported in Ge to date. 'Inverted' structures (doping layer under the channel) were also studied for different sample parameters such as channel thickness, spacer thickness, doping and different temperature growth, with a hole
mobility as high as 5.08×105 cm2 /Vs at a sheet density of 5.14×1011 cm-2 at 90 mK.
Simulations of the scattering limited mobility for inverted and normal structures were performed and showed that at low sheet density background impurity scattering limits the low temperature hole mobility. However, as the sheet density increases interface roughness scattering becomes the mobility limiting process, especially in the case of inverted structures where the resistivity and mobility anisotropy is more pronounced.
Magnetotransport measurements revealed the lowest reported effective mass for holes in Ge of 0.063±0.001 m0 for the normal structure and 0.07±0.002 m0 & 0.063±0.003 m0 for two inverted structures, and highest Dingle factors of α=78 and 33 for the normal and inverted structures, respectively. The low level of background impurities, high structural quality, and pure Ge channel revealed by structure characterisation are believed to be responsible for these exceptionally high values of mobility
Contact analysis and mathematical modeling of traveling wave ultrasonic motors
No full textAn analysis of the contact layer and a mathematical modeling of traveling wave ultrasonic motors (TWUM) are presented for the guidance of the design of contact layer and the analyses of the influence of the compressive force and contact layer on motor performance. The proposed model starts from a model previously studied but differs from that model in that it adds the analysis of the contact layer and derives the steady-state solutions of the nonlinear equations in the frequency domain, rather than in the time domain, for the analyses of vibrational responses of the stator and operational characteristics of the motor. The maximum permissible compressive force of the motor, the influences of the contact layer material, the thickness of the contact layer, and the compressive force on motor performance have been discussed. The results show that by using the model, one can understand the influence of the compressive force and contact layer material on motor performance, guide the choice of proper contact layer material, and calculate the maximum permissible compressive force and starting voltage.IEEE Transaction on Ultrasonics, Ferroelectrics and Frequency Contro
Electrodeposited Ni/Ge and germanide schottky barriers for nanoelectronics applications
No full textIn recent years metal/semiconductor Schottky barriers have found numerous applications in nanoelectronics. The work presented in this thesis focuses on the improvement of a few of the relevant devices using electrodeposition of metal on Ge for Schottky barrier fabrication. This low energy metallisation technique offers numerous advantages over the physical vapour deposition techniques. Electrical characteristics of the grown diodes show a high quality rectifying behaviour with extremely low leakage currents even on highly doped Ge. A non-Arrhenius behaviour of the temperature dependence is observed for the grown Ni/Ge diodes on lowly doped Ge that is explained by a spatial variation of the barrier heights. The inhomogeneity of the barrier hights is explained in line with an intrinsic surface states model for Ge. The understanding of the intrinsic surface states will help to create ohmic contacts for doped n-MOSFETs. NiGe were formed single phase by annealing. Results reveal that by using these high-quality germanide Schottky barriers as the source/drain, the subthreshold leakage currents of a Schottky barrier MOSFET could be minimised, in particular, due to the very low drain/body junction leakage current exhibited by the electrodeposited diodes. The Ni/Ge diodes on highly doped Ge show negative differential conductance at low temperature. This effect is attributed to the intervalley electron transfer in Ge conduction band to a low mobility valley. The results show experimentally that Schottky junctions could be used for hot electron injection in transferred-electron devices. A vertical Co/Ni/Si structure has been fabricated for spin injection and detection in Si. It is shown that the system functions electrically well although no magnetoresistance indicative of spin injection was observed
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