SiGe Heteroepitaxy for High Frequency Circuits

1998 ◽  
Vol 525 ◽  
Author(s):  
B. Tillack ◽  
D. Bolze ◽  
G. Fischer ◽  
G. Kissinger ◽  
D. Knoll ◽  
...  
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
High Frequency ◽  
Defect Density ◽  
Process Capability ◽  
Chemical Vapor ◽  
Bipolar Transistors ◽  
Capability Indices ◽  
Data Points ◽  
B Doping ◽  
The Stability

ABSTRACTWe have determined the process capability of Low Pressure (Rapid Thermal) Chemical Vapor Deposition (LP(RT)CVD) of epitaxial Si/SiGe/Si stacks for heterojunction bipolar transistors (HIBTs). The transistor parameters primarily influenced by the epitaxial characteristics were measured for 600 identically processed 4” wafers. The results demonstrate that it is possible to control accurately the epitaxial process for a 25 nm thick graded SiGe base profile with 20 % Ge and very narrow B doping (5 nm). The pipe limited device yield of about 90 % for an emitter area of 104 μm2 indicates a very low defect density in the epitaxial layer stack. The process capability indices determined from about 40,000 data points demonstrate the stability and capability of the LP(RT)CVD epitaxy with regard to manufacturing requirements.

Integration of Si-MBE and Device Processing

1991 ◽  
Vol 220 ◽  
Author(s):  
D. J. Gravesteijn ◽  
G. F. A. Van De Walle ◽  
A. Pruijmboom ◽  
A. A. Van Gorkum
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Detrimental Effect ◽  
Defect Density ◽  
Bipolar Transistors ◽  
Current Gain ◽  
Gain Enhancement ◽  
Transient Diffusion ◽  
Device Processing ◽  
Background Doping ◽  
The Stability

ABSTRACTA review is given of the requirements on MBE-grown layers as far as processing is concerned. Aspects that are considered are: defect density, particulates, background doping and metallic contamination. The stability of the grown layers against thermal anneals is considered. It is shown that normal thermal diffusion in HBT structures is not important, other effects, like transient diffusion following ion implantation, have drastic effects on the grown profiles. As an example the processing of mesa-isolated heterojunction bipolar transistors is treated. It is shown that all-Si transistors can be grown with ideal Gummel plots. The Gummel plots of SiGe HBTs show small non-idealities. The current gain enhancement of the HBTs with respect to the all-Si transistors is shown to be as large as 200 times. Due to transient diffusion, parasitic barriers are formed, that have a detrimental effect on the AC and DC performance.

TEM evaluation of graded SixGe1-x heterolayers

1991 ◽  
Vol 49 ◽  
pp. 894-895
Author(s):  
N. David Theodore ◽  
Mamoru Tomozane ◽  
Ming Liaw
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Gas Flow ◽  
Field Effect Transistors ◽  
Chemical Vapor ◽  
Dark Field ◽  
Bipolar Transistors ◽  
Structural Quality ◽  
Weak Beam ◽  
Transmission Electron ◽  
And Behavior

There is extensive interest in SiGe for use in heterojunction bipolar transistors. SiGe/Si superlattices are also of interest because of their potential for use in infrared detectors and field-effect transistors. The processing required for these materials is quite compatible with existing silicon technology. However, before SiGe can be used extensively for devices, there is a need to understand and then control the origin and behavior of defects in the materials. The present study was aimed at investigating the structural quality of, and the behavior of defects in, graded SiGe layers grown by chemical vapor deposition (CVD).The structures investigated in this study consisted of Si1-xGex[x=0.16]/Si1-xGex[x= 0.14, 0.13, 0.12, 0.10, 0.09, 0.07, 0.05, 0.04, 0.005, 0]/epi-Si/substrate heterolayers grown by CVD. The Si1-xGex layers were isochronally grown [t = 0.4 minutes per layer], with gas-flow rates being adjusted to control composition. Cross-section TEM specimens were prepared in the 110 geometry. These were then analyzed using two-beam bright-field, dark-field and weak-beam images. A JEOL JEM 200CX transmission electron microscope was used, operating at 200 kV.

High-frequency output characteristics of AlGaAs/GaAs heterojunction bipolar transistors

1990 ◽  
Vol 26 (25) ◽  
pp. 2058 ◽  
Author(s):  
J. Chen ◽  
G.B. Gao ◽  
M.S. Ünlü ◽  
H. Morkoç
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
High Frequency ◽  
Bipolar Transistors ◽  
Frequency Output ◽  
Output Characteristics

Growth and Characterization of High-Speed Carbon-Doped-Base InP/InGaAs Heterojunction Bipolar Transistors by Metalorganic Chemical Vapor Deposition

1996 ◽  
Vol 35 (Part 1, No. 6A) ◽  
pp. 3343-3349 ◽  
Author(s):  
Hiroshi Ito ◽  
Shoji Yamahata ◽  
Naoteru Shigekawa ◽  
Kenji Kurishima ◽  
Yutaka Matsuoka
Keyword(s):  
Chemical Vapor Deposition ◽  
Heterojunction Bipolar Transistors ◽  
Vapor Deposition ◽  
High Speed ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Bipolar Transistors ◽  
Carbon Doped ◽  
Metalorganic Chemical

Fabrication of Boron Compensated Hydrogenated Amorphous Silicon Films with Significantly Improved Stability Using Plasma Enhanced Chemical Vapor Deposition Technique

1995 ◽  
Vol 377 ◽  
Author(s):  
Mohan K. Bhan
Keyword(s):  
Chemical Vapor ◽  
Short Term ◽  
Term Stability ◽  
Long Term Stability ◽  
Vapor Deposition Technique ◽  
Improved Stability ◽  
Donor Acceptor ◽  
B Doping ◽  
The Stability

ABSTRACTWe have systematically investigated the effects of addition of sub-ppm levels of boron on the stability of a-Si:H films and p-i-n devices, deposited by PE-CVD technique. The films thus produced with appropriate amounts of boron, show a significant improvement in stability, when soaked under both AM 1.5 (short-term) as well as 10×sun (long-term) illumination conditions. The opto-electronic properties of the films are quite respectable It is concluded that boron compensates the native impurities by forming donor-acceptor pairs, which reduces the “fast” defects and hence the initial degradation of the films. It is also speculated that boron may also be improving the short-term stability, by reducing the recombination of light generated electrons and holes, by converting D° into D+ states. The long-term stability appears to get affected by hydrogen dilution which seems to reduce the amount of “slow” defects. As a result of B doping of i-layer, the initial conversion efficiency of the devices decreases. It is presumed that our devices may contain an enhanced level of boron impurity, than expected, making them as worse material and to degrade less.

High frequency Si/Si/sub 1-x/Ge/sub x/ heterojunction bipolar transistors

2003 ◽  
Author(s):  
T.I. Kamins ◽  
K. Nauka ◽  
L.H. Camnitz ◽  
J.B. Kruger ◽  
J.E. Turner ◽  
...  
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
High Frequency ◽  
Bipolar Transistors
Sign in / Sign up

Export Citation Format

Share Document