Heavily Doped Ultra-Shallow Junctions Formed by an ArF Excimer Laser

1988 ◽  
Vol 129 ◽  
Author(s):  
S. Yoshioka ◽  
J. Wada ◽  
H. Saeki ◽  
S. Matsumoto
Keyword(s):  
Excimer Laser ◽  
High Surface ◽  
Single Crystal Silicon ◽  
Surface Concentration ◽  
Crystal Silicon ◽  
Ultrashallow Junctions ◽  
High Surface Concentration ◽  
Heavily Doped ◽  
Ultra Shallow Junctions ◽  
Argon Fluoride

ABSTRACTBoron doping of single crystal silicon using an argon fluoride excimer laser with diborane gas has been performed. Diborane gas has an absorption at 193nm, which leads to gas phase photodecomposition of the diborane. Utilizing the photolyic effect, we obtained high surface concentration and ultrashallow junctions of 5×1020 cm−3 and 0.1 µm, respectively. The photolytic effect enhances the incorporation of the dopant species.

Fabrication of Ultra-Shallow P+-N and N+-P Junctions by Diffusion From Selectively Deposited, Ion-Implanted and In-Situ Doped Si0.7Ge0.3

1993 ◽  
Vol 303 ◽  
Author(s):  
D.T. Grider ◽  
M.C. ÖztÜrk ◽  
J.J. Wortman ◽  
G.S. Harris ◽  
D.M. Maher
Keyword(s):  
High Surface ◽  
Chemical Vapor ◽  
Surface Concentration ◽  
Shallow Junctions ◽  
High Surface Concentration ◽  
Diffusion Source ◽  
Ultra Shallow Junctions ◽  
P Type ◽  
Ion Implanted

ABSTRACTSelectively deposited Si0.7Ge0.3 has been investigated as a potential diffusion source for fabricating ultra-shallow junctions in Si. Rapid thermal chemical vapor deposition (RTCVD) was used to selectively deposit Si0.7Ge0.3 on Si using SiH2C12, GeH4, and H2. Both ionimplanted and in-situ doped Si0.7Ge0.3 were considered as a diffusion source for fabricating ultra-shallow junctions. In-situ doping was achieved with B2H6 and PH3 for p-type and n-type doping, respectively. Boron and phosphorus diffusion in ion-implanted Si0.7Ge0.3 was investigated and modeled using SSUPREM4. Diffusion from implanted and in-situ doped Si0.7Ge0.3 in Si was also studied and modeled. Boron diffusivities in Si0.7Ge0.3 were found to be approximately 10 times greater than in Si, while phosphorus diffusivities were over 100 times greater in Si0.7Ge0.3. The faster dopant diffusivities in Si0.7Ge0.3 allow high surface concentration, abrupt diffusion profiles to be formed in Si. Gated, p-n junction diodes with junction depths as shallow as 140Å were fabricated and tested to study the quality of the diffusions from Si0.7Ge0.3.

A Steady-State Model for Coupled Defect Impurity Diffusion in Silicon

1989 ◽  
Vol 163 ◽  
Author(s):  
F. F. Morehead ◽  
R. F. Lever
Keyword(s):  
Steady State ◽  
High Surface ◽  
Local Equilibrium ◽  
Surface Concentration ◽  
Extended Model ◽  
High Concentration ◽  
Steady State Model ◽  
High Surface Concentration ◽  
Phosphorus In Silicon ◽  
Diffusion Profiles

AbstractWe extend our earlier model which was proposed to explain tails in the diffusion profiles of high concentration boron and phosphorus in silicon. Our quasi-steady-state approach is generalized here to include both vacancies (V) and interstitials (I) at equivalent levels. I-V recombination is regarded as near local equilibrium, occurring through reactions of the defects with defect-impurity pairs. This approach leads to the well-known plateau, kink and tail in high surface concentration P diffusions in Si and to the less well recognized tails in B as well. Our extended model, in its simplest form, allows a more complete and less restrictive treatment of Au diffusion in Si. An important advantage is the direct inclusion of these defect-impurity interactions and the resulting gradients in the defect concentrations.

Effect of Microalloying with Ti or Cr on the Corrosion Behavior of Al-Ni-Y Amorphous Alloys

CORROSION ◽  
10.5006/2451 ◽  
2017 ◽  
Vol 74 (1) ◽  
pp. 66-74 ◽  
Author(s):  
L.M. Zhang ◽  
A.L. Ma ◽  
H.X. Hu ◽  
Y.G. Zheng ◽  
B.J. Yang ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Photoelectron Spectroscopy ◽  
Amorphous Alloys ◽  
Diffusion Mechanism ◽  
High Surface ◽  
Control Sample ◽  
Surface Concentration ◽  
Passive Films ◽  
High Surface Concentration

The effect of microalloying with Ti or Cr on the corrosion behavior of Al-Ni-Y amorphous alloys in 0.1 M NaCl solution was studied by potentiodynamic polarization, Mott-Schottky, and x-ray photoelectron spectroscopy techniques. Microalloying with Ti or Cr could greatly improve the corrosion resistance of Al-Ni-Y amorphous alloys. A high surface concentration of Ti or Cr in the passive films was detected, which should be responsible for the improved corrosion resistance compared to the control sample. The possible process of Ti or Cr involved in the passive films was proposed in terms of the point defect model and the vacancy diffusion mechanism. Furthermore, the effect of Ti was stronger than Cr because of the higher film resistance as well as the higher surface concentration. The different passivation abilities and atomic radiuses between Ti and Cr were presented to explain the better microalloying effect of Ti compared to Cr.

A New Model of Tail Diffusion of Phosphorus and Boron in Silicon

1985 ◽  
Vol 52 ◽  
Author(s):  
Frederick F. Morehead ◽  
R. F. Lever
Keyword(s):  
Concentration Profile ◽  
Process Simulation ◽  
Low Temperatures ◽  
High Surface ◽  
Surface Concentration ◽  
Transient Effects ◽  
Phosphorus Diffusion ◽  
High Surface Concentration ◽  
Conventional Models ◽  
Normal Processing

ABSTRACTIt is well known that high surface concentration phosphorus diffusion leads to deeply penetrating “tails” in its concentration profile. At 700 °C the tail diffusivity exceeds that of low concentration phosphorus by a factor of a thousand. Less spectacular, but very significant tailing also affects tioron, making the conventional models contained in commonly available process simulation programs quite inaccurate for boron diffusions with high surface concentrations. We show that the observed tailing can be accounted for by a model whose central assumption is the local equality of dopant and oppositely directed defect fluxes. As predicted by the model, the effect is greatest for normal processing at low temperatures for high surface concentrations. It is minimal for the high temperatures of rapid thermal annealing and unrelated to transient effects.

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