Degradation and Recovery of Si1−xGex Devices by Irradiation

1995 ◽  
Vol 379 ◽  
Author(s):  
H. Ohyama ◽  
J. Vanhellemont ◽  
Y. Takami ◽  
K. Hayama ◽  
T. Kudo ◽  
...  
Keyword(s):  
Neutron Irradiation ◽  
Heterojunction Bipolar Transistors ◽  
Radiation Source ◽  
Bipolar Transistors ◽  
Isochronal Annealing ◽  
Device Performance ◽  
Absorbed Energy ◽  
Strained Si ◽  
Germanium Content ◽  
Recovery Behavior

ABSTRACTResults are presented of a study on the degradation and recovery behavior of strained Si 1−xGex diodes and heterojunction bipolar transistors (HBTs) by electron and neutron irradiation. The degradation of device performance and the generation of lattice defects are reported as a function of germanium content and radiation source. Isochronal annealing is performed to study the recovery behavior of the irradiated devices. The radiation source dependence of the degradation is discussed taking into account the absorbed energy dunng irradiation.

The Use of Low Temperature AlInAs and GalnAs Lattice Matched to InP in the Fabrication of HBTs and HEMTs

1991 ◽  
Vol 241 ◽  
Author(s):  
R. A. Metzger ◽  
A. S. Brown ◽  
R. G. Wilson ◽  
T. Liu ◽  
W. E. Stanchina ◽  
...  
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Normal Growth ◽  
High Electron Mobility Transistors ◽  
Bipolar Transistors ◽  
Device Performance ◽  
High Electron ◽  
High Electron Mobility ◽  
Temperature Range ◽  
Electron Mobility Transistors ◽  
Lattice Matched

ABSTRACTAlInAs and GaInAs lattice matched to InP and grown by MBE over a temperature range of 200 to 350°C (normal growth temperature of 500°C) has been used to enhance the device performance of inverted (where the donor layer lies below the channel) High Electron Mobility Transistors (HEMTs) and Heterojunction Bipolar Transistors (HBTs), respectively. We will show that an AlInAs spacer grown over a temperature range of 300 to 350°C and inserted between the AlInAs donor layer and GaInAs channel significantly reduces Si movement from the donor layer into the channel. This produces an inverted HEMT with a channel charge of 3.0×1012 cm−2 and mobility of 9131 cm2/V-s, as compared to the same HEMT with a spacer grown at 500 °C resulting in a channel charge of 2.3×1012 cm−2 and mobility of 4655 cm2/V-s. We will also show that a GaInAs spacer grown over a temperature range of 300 to 350°C and inserted between the AlInAs emitter and GalnAs base of an npn HBT significantly reduces Be movement from the base into the emitter, thereby allowing higher Be base dopings (up to 1×1020 cm−3) confined to 500 Å base widths, resulting in an AlInAs/GaInAs HBT with an fmax of 73 GHz and ft of 110 GHz.

Study of The Transversal Electron Mobility in Heterojunction Bipolar Transistors with Strained SI1−x Gex-Base

1992 ◽  
Vol 281 ◽  
Author(s):  
J. Poortmans ◽  
M. Caymax ◽  
A. Van Ammel ◽  
M. Libezny ◽  
J. Nijs
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Electron Mobility ◽  
Doping Level ◽  
Theoretical Calculations ◽  
Bipolar Transistors ◽  
Effective Density ◽  
Collector Current ◽  
Strained Si ◽  
Strained Layers ◽  
B Doping

ABSTRACTThe effective transversal mobility of the minority carrier electrons in asymmetrically strained p-type Si1−x Gex -layers, grown on a Si (100) substrate, is studied as a function of boron doping concentration and Ge-content x. The experiments are based on the temperature dependence (290 to 400K) of the collector current enhancement of heterojunction bipolar transistors with a pseudomorphic Si1−x Gex-base. The interpretation of these results is based on new insights about the effective density of states in the valence band of these strained layers [1]. We will present first experimental evidence of the theoretical calculations in [1]. From this we will derive then the value of the NcNv -product for the strained Si1−x Gex-alloy. This allows to extract the ratio of the electron mobility in Si and strained Si1−xGex. We found an enhancement of the mobility when the B-doping level is around 1018 cm−3 and 0.08<x<0.16. At higher values of the Ge-content and the doping level, the enhancement is reduced again.

Low Frequency Noise in Strained Si Heterojunction Bipolar Transistors

2011 ◽  
Vol 58 (12) ◽  
pp. 4196-4203
Author(s):  
M. Fjer ◽  
S. Persson ◽  
E. Escobedo-Cousin ◽  
A. G. O'Neill
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Low Frequency ◽  
Bipolar Transistors ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Strained Si

Self-Aligned Process For Emitter- And Base- Regrowth GaN HBTs And BJTs

2000 ◽  
Vol 639 ◽  
Author(s):  
K. P. Lee ◽  
A. P. Zhang ◽  
G. Dang ◽  
F. Ren ◽  
J. Han ◽  
...  
Keyword(s):  
Contact Area ◽  
Heterojunction Bipolar Transistors ◽  
Series Resistance ◽  
Dry Etching ◽  
Bipolar Transistors ◽  
Fabrication Process ◽  
Device Performance ◽  
Bipolar Junction Transistors ◽  
Dielectric Spacer ◽  
Base Contact

ABSTRACTThe development of a self-aligned fabrication process for small emitter contact area (2×4 um2) GaN/AlGaN heterojunction bipolar transistors and GaN bipolar junction transistors is described. The process features dielectric-spacer sidewalls, low damage dry etching and selected-area regrowth of p-GaAs(C) on the base contact or n-GaN/AlGaN on the emitter contact. Series resistance effects are still found to influence the device performance.

Effects of neutron irradiation on GaAs/AlGaAs heterojunction bipolar transistors

1989 ◽  
Vol 36 (6) ◽  
pp. 2155-2160 ◽  
Author(s):  
Y. Song ◽  
M.E. Kim ◽  
A.K. Oki ◽  
M.E. Hafizi ◽  
W.D. Murlin ◽  
...  
Keyword(s):  
Neutron Irradiation ◽  
Heterojunction Bipolar Transistors ◽  
Bipolar Transistors

FABRICATION TECHNIQUES FOR SELF-ALIGNED GaAs-BASED HBTs AND SUBMICRON GATE LENGTH FETs

1994 ◽  
Vol 08 (16) ◽  
pp. 2221-2243
Author(s):  
F. REN
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Ohmic Contact ◽  
Field Effect Transistors ◽  
Bipolar Transistors ◽  
Device Performance ◽  
Gate Length ◽  
Active Devices ◽  
Etching Selectivity ◽  
Gate Recess ◽  
Wet Etch

Process technologies for self-aligned AlGaAs/GaAs and InGaP/GaAs heterojunction bipolar transistors (HBTs) as well as gate definition and dry etching fabrication schemes for submicron gate length AlGaAs/GaAs-based field effect transistors (FETs) are presented. Multiple energy F + and H + ions were used to isolate the active devices for HBTs. The resistance of test wafers at 200° C showed no change over periods of more than 50 days. Highly selective dry and wet etch techniques for InGaP/GaAs and AlGaAs/GaAs material systems were used to uniformly expose heterojunctions. Reliability of the alloyed ohmic contact and feasibility of the nonalloyed ohmic contact metallizations for both p and n type GaAs layers will be discussed. The reproducible gate recess etching is one of the critical steps for AlGaAs/GaAs-based FETs. The etching selectivity, damage, pre- and post-clean procedures were studied in terms of device performance. A simple low temperature SiN x deposition and an etch-back process with optical stepper were used to demonstrate 0.1 µm Y-shape gate feature.

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