Rapid thermal annealing of in situ phosphorus-doped polysilicon emitters

1992 ◽  
Vol 70 (10-11) ◽  
pp. 1109-1111 ◽  
Author(s):  
Gary F. Mackay ◽  
Brendon M. Manning ◽  
N. Garry Tarr

Rapid thermal annealing of in situ phosphorus-doped polysilicon emitter transistors in the temperature range 850–1000 °C greatly reduces the emitter resistance RE at the cost of a slight increase in hole back injection, seen as a decrease in emitter Gummel number GE. Annealing at 1000 °C for 5 s gives low emitter resistance (RE ≈ 100 Ω μm2) while maintaining good suppression of back injection (GE ≥ 1014 scm−4). Annealing at temperatures below 1000 °C fails to reduce RE sufficiently for use in high-speed devices.

1989 ◽  
Vol 67 (4) ◽  
pp. 179-183 ◽  
Author(s):  
E. P. Keyes ◽  
N. G. Tarr

The effect of 900 °C furnace annealing on transistors with in situ phosphorus-doped polysilicon emitters has been investigated. For devices with chemically grown interfacial oxides, annealing is essential to give acceptable emitter resistance and emitter Gummel numbers. For devices lacking an intentionally grown interfacial oxide, annealing is necessary to reduce the emitter resistance to a tolerable level, but it simultaneously lowers the emitter Gummel number.


1994 ◽  
Vol 375 ◽  
Author(s):  
C. Cabral ◽  
L. A. Clevenger ◽  
G. B. Stephenson ◽  
S. Brauer ◽  
G. Morales ◽  
...  

AbstractIt has been demonstrated, using synchrotron radiation, that at rapid thermal annealing rates (3°C/s) the formation of CoSi2 shifts to higher temperatures when a thin Ti interlayer is placed between Co and polycrystalline Si. It has also been shown that the Ti interlayer reduces the temperature range between the start of CoSi formation and CoSi2 formation (i.e. the range over which CoSi is present). 13 nm of Co deposited by physical vapor deposition on polycrystalline Si with and without either a 2 nm or 3.4 nm interlayer of Ti was analyzed in-situ by monitoring x-ray diffraction (XRD) peak intensity as a function of temperature using monochromatic radiation from a synchrotron beam line and by monitoring resistivity as a function of temperature in a rapid thermal annealing (RTA) system. The XRD analysis indicates that the phase formation proceeds from CoSi to CoSi2 in a temperature range that decreases from about 200°C to 140°C to 115°C with pure Co, Co/2 nm Ti and Co/3.4 nm Ti films respectively. The onset of the CoSi formation increases by about 135°C and 160° for Co/ 2 nm Ti and Co/3.4 nm Ti compared to pure Co. The CoSi temperature range decreases from about 75°C in pure Co to less than 50°C in Co/Ti. In-situ RTA resistance along with in-situ XRD analysis indicates that the onset formation temperatures for CoSi are about 440°C, 575°C and 600°C and the temperatures for the completion of CoSi2 formation are about 640°C, 715°C and 715°C for Co, Co / 2 nm Ti and Co / 3.4 nm Ti films respectively. The results are consistent with the Ti interlayer acting as a diffusion barrier during the initial stages of the Co-Si reaction.


1995 ◽  
Vol 402 ◽  
Author(s):  
L. A. Clevenger ◽  
C. Cabral ◽  
R. A. Roy ◽  
C. Lavoie ◽  
R. Viswanathan ◽  
...  

AbstractA detailed in situ study of silicide reactions during rapid thermal annealing of patterned structures was performed to determine the effects of linewidth (0.2 to 1.1 μm), dopants (arsenic, boron or phosphorus) and silicon substrate type (poly-Si or <100>-Si) on the C49 to C54-TiSi2 transformation. A synchrotron x-ray source and a high speed position sensitive detector were used to collect x-ray diffraction patterns of the reacting phases on a millisecond time scale, in situ, during annealing. We demonstrate that most patterned C49-TiSi2 structures (0.2 to 1.1 μm in width, 2 to 4 μm2 in area) will incompletely transform into C54-TiSi2 during rapid thermal annealing. The C49 to C54 transformation ends at about 900°C and further annealing to higher temperatures does not force the remaining C49 to transform into C54. We also observed that the C54 formation temperature increases as the linewidth of the silicide structure decreases. These results are explained by a low density of C54 nuclei in C49 which leads to a one-dimensional growth of C54 grains along the length of the patterned lines. Finally the incorporation of a Mo implant into either poly-Si or <100>-Si before the deposition of titanium is shown to increase the percentage of C49 that transforms into C54 and also to lower the C54 formation temperature.


1999 ◽  
Vol T79 (1) ◽  
pp. 318 ◽  
Author(s):  
W. Kaplan ◽  
J. Pejnefors ◽  
M. Linder ◽  
M. Sand?n ◽  
T. E. Karlin ◽  
...  

1987 ◽  
Vol 102 ◽  
Author(s):  
M. Cerullo ◽  
Julia M. Phillips ◽  
M. Anzlowar ◽  
L. Pfeiffer ◽  
J. L. Batstone ◽  
...  

ABSTRACTA new in-situ rapid thermal annealing (RTA) apparatus which can be used to anneal entire wafers in an ultra high vacuum environment has been designed to be used in conjunction with the epitaxial growth of heterostructures. Drastic improvement in the crystallinity of CaF2/Si(100) can be achieved with RTA, and our results suggest that RTA can be used as an on-line processing technique for novel epitaxial structures.


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