An analytical and experimental investigation of the cutoff frequency f/sub T/ of high-speed bipolar transistors

1988 ◽  
Vol 35 (7) ◽  
pp. 1021-1028 ◽  
Author(s):  
M. Nanba ◽  
T. Shiba ◽  
T. Nakamura ◽  
T. Toyabe
1994 ◽  
Vol T54 ◽  
pp. 136-138
Author(s):  
M Andersson ◽  
P Kuivalainen ◽  
Z Xia ◽  
H Pohjonen ◽  
H Ronkainen

Author(s):  
N. David Theodore ◽  
Donald Y.C Lie ◽  
J. H. Song ◽  
Peter Crozier

SiGe is being extensively investigated for use in heterojunction bipolar-transistors (HBT) and high-speed integrated circuits. The material offers adjustable bandgaps, improved carrier mobilities over Si homostructures, and compatibility with Si-based integrated-circuit manufacturing. SiGe HBT performance can be improved by increasing the base-doping or by widening the base link-region by ion implantation. A problem that arises however is that implantation can enhance strain-relaxation of SiGe/Si.Furthermore, once misfit or threading dislocations result, the defects can give rise to recombination-generation in depletion regions of semiconductor devices. It is of relevance therefore to study the damage and anneal behavior of implanted SiGe layers. The present study investigates the microstructural behavior of phosphorus implanted pseudomorphic metastable Si0.88Ge0.12 films on silicon, exposed to various anneals.Metastable pseudomorphic Si0.88Ge0.12 films were grown ~265 nm thick on a silicon wafer by molecular-beam epitaxy. Pieces of this wafer were then implanted at room temperature with 100 keV phosphorus ions to a dose of 1.5×1015 cm-2.


2012 ◽  
Vol 43 (4) ◽  
pp. 481-496 ◽  
Author(s):  
Valeriy Ivanovich Zapryagaev ◽  
Nikolay Petrovich Kiselev ◽  
Dmitriy Andreevich Gubanov

2004 ◽  
Vol 14 (03) ◽  
pp. 625-631 ◽  
Author(s):  
J. W. LAI ◽  
W. HAFEZ ◽  
M. FENG

We have fabricated the high-speed InP/InGaAs -based single heterojunction bipolar transistors (SHBTs) with current gain cutoff frequency, fT from 166GHz to over 500GHz by the approach of vertical scaling. Collector thickness is reduced from 3000Å to 750Å and the peak current density is increased up to 1300kA/cm2. In this paper, device rf performance has been compared with respect to materials with different vertical dimensions. The scaling limitation is also studied by analytical approach. The extracted physical parameters suggest that the parasitic emitter resistance is the major limit on further enhancing ultra-scaled HBT intrinsic speed due to the associated RECBC delay. The cut-off frequency of a 500Å collector SHBT has been measured and the results indicate a dramatic drop on fT, supporting the conclusion projected by model analysis. It is also commented that for deeply downscaled HBTs, impact ionization could be another degrading mechanism limits device bandwidth.


2001 ◽  
Vol 36 (9) ◽  
pp. 1390-1398 ◽  
Author(s):  
J.C.J. Paasschens ◽  
W.J. Kloosterman ◽  
R.J. Havens ◽  
H.C. de Graaff

2013 ◽  
Vol 420 ◽  
pp. 47-50
Author(s):  
Ying Yang ◽  
Jing Hua Dai

Under high and super-high speed, oil film of the journal bearing is easy to crack and then becomes cavitation. The existence of cavitation has an important effect on the work characteristics of the shaft. On the journal bearing experiment rig the cavitation characteristics of the three-groove journal beaing were studied. The influences of the shaft rotating speed and supply pressure on cavitation shape were investigated. The results show that rotating speed and supply pressure have a clear effect on the cavitation shape, and the number of cavitation strip in the rupture zone decreases when the supply pressure increases.


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