Semiconductor device manufacturing: process – Making field effect device having pair of active regions... – On insulating substrate or layer
Reexamination Certificate
1993-07-23
2001-08-07
Booth, Richard (Department: 2812)
Semiconductor device manufacturing: process
Making field effect device having pair of active regions...
On insulating substrate or layer
C438S308000
Reexamination Certificate
active
06271066
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor material, e.g., containing silicon as the major component. More particularly, the present invention relates to a thin film silicon semiconductor material improved in properties and a process for fabricating the same. The semiconductor material according to the present invention enables fabrication of thin film semiconductor devices such as thin film transistors having excellent device characteristics.
2. Description of the Prior Art
Non-crystalline semiconductor materials (the so-called amorphous semiconductors) and polycrystalline semiconductor materials have been heretofore used for the fabrication of thin film semiconductor devices such as thin film field effect transistors and the like. The term “amorphous materials” as referred herein signifies not only the materials having a structural disordering in the strict sense of atomic level, but also includes those having a short range ordering for a distance of about several nanometers. More concretely, “amorphous materials” include silicon materials having an electron mobility of 10 cm
2
/V·s or lower and materials having a carrier mobility lowered to 1% or less of the intrinsic carrier mobility of the corresponding semiconductor material.
The use of an amorphous semiconductor such as amorphous silicon (a-Si) and amorphous germanium (a-Ge) in the fabrication of a semiconductor device is advantageous in that the process can be conducted at a relatively low temperature of 400° C. or even lower. Thus, much attention is paid now to a process using an amorphous material, because such a process is regarded as promising for the fabrication of liquid crystal displays and the like, to which a high temperature process cannot be applied.
However, a pure amorphous semiconductor has an extremely low carrier mobility (electron mobility and hole mobility). Thus, pure amorphous semiconductors are seldom applied as they are, for example, to channel-forming areas of thin film transistors (TFTs). In general, the pure amorphous semiconductor materials are subjected to the irradiation of a high energy beam such as a laser beam or a light emitted from a xenon lamp, so that they may be once molten to recrystallize and thereby be modified into a crystalline semiconductor material having an improved carrier mobility. Such a treatment of high energy light beam irradiation is referred hereinafter collectively to as “laser annealing”. It should be noted, however, that the high energy beam not necessary be a laser beam, and included in the high intensity beam is, for example, a powerful light emitted from a flash lamp which has a similar effect on the semiconductor material as the laser beam irradiation.
Generally, however, the semiconductor materials heretofore obtained by laser annealing are still low in the carrier mobility as compared with those of single crystal semiconductor materials. In the case of a silicon film, for example, the highest reported electron mobility is 200 cm
2
/V·s at best, which is a mere one seventh of the electron mobility of a single silicon, 1350 cm
2
/V·s. Moreover, the semiconductor characteristics (mainly mobility) of the semiconductor material thus obtained by the laser annealing process suffers poor reproducibility and also scattering of the mobility values over the single film. Those disadvantages lead to a low product yield of semiconductor devices having a plurality of elements fabricated on a single plane.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a semiconductor material having a high mobility and a method for forming the same with excellent reproducibility. More specifically, an object of the present invention is to provide a process in which the problems of the conventional laser annealing process are overcome, and to provide, accordingly, a practically feasible thin film semiconductor material improved in characteristics.
REFERENCES:
patent: 4266986 (1981-05-01), Benton et al.
patent: 4727044 (1988-02-01), Yamazaki
patent: 4766477 (1988-08-01), Nakagawa et al.
patent: 4959700 (1990-09-01), Yamazaki
patent: 5091334 (1992-02-01), Yamazaki et al.
patent: 5210050 (1993-05-01), Yamazaki et al.
patent: 5272361 (1993-12-01), Yamazaki
patent: 5278093 (1994-01-01), Yonehara
patent: 5306651 (1994-04-01), Masumo et al.
patent: 5313077 (1994-05-01), Yamazaki
patent: 5315132 (1994-05-01), Yamazaki
patent: 5543636 (1996-08-01), Yamazaki
patent: 0178447 (1986-04-01), None
patent: 420516 (1991-04-01), None
patent: 53-027483 (1978-03-01), None
patent: 56-23748 (1981-03-01), None
patent: 56-137642 (1981-10-01), None
patent: 56-137641 (1981-10-01), None
patent: 57-115856 (1982-07-01), None
patent: 58-199564 (1983-11-01), None
patent: 60-58675 (1985-04-01), None
patent: 60-245124 (1985-12-01), None
patent: 60-245173 (1985-12-01), None
patent: 62-104117 (1987-05-01), None
patent: 63-25913 (1988-02-01), None
patent: 63-288010 (1988-11-01), None
patent: 64-53553 (1989-03-01), None
patent: 1-241862 (1989-09-01), None
patent: 2-81424 (1990-03-01), None
patent: 2-170522 (1990-07-01), None
patent: 2-239615 (1990-09-01), None
patent: 2-238617 (1990-09-01), None
patent: 2-226718 (1990-09-01), None
patent: 3-109717 (1991-05-01), None
patent: 3-246973 (1991-11-01), None
patent: 4-180617 (1992-06-01), None
patent: 4-186635 (1992-07-01), None
Wolf et al., “Silicon Processing for the VLSI Era vol. 1: Process Technology”, Lattice Press, pp. 179-180 1986.*
Yuki et al., “A Full-Color LCD Addressed by Poly-Si TFT's Fabricated Below 450oC”, IEEE Transactions on Electron Devices, vol. 36, No. 9, pp. 1934-1937 Sep. 1989.*
Masumo et al., “Low Temperature Fabrication of Poly-Si TFT by Laser Induced Crystallization of a-Si”, Journal of Non-Crystalline Solids, vol. 115, pp. 147-149, 1989.*
Pressley, “Excimer Laser Processing of Semiconductors”, Lasers & Applications, May 1985, pp. 93-98.*
Pummer, “Commercial Excimer Lasers”, Scientific and Engineering Applications of Commerical Laser Devices, 1986, pp. 38-42.*
Wolf et al., “Silicon Processing for the VLSI Era vol. I: Process Technology”, pp. 303-308, 1986.*
Sera et al., “High-Performance TFT's Fabricated by XeCl Excimer Laser Annealing of Hydrogenated Amporphous-Silicon Film”, IEEE, Transactions on Electron Devices, 36 (1989), pp. 2868-2872.*
Kiang et al, “Modification of Semiconductor Device Characteristics by Lasers”, IBM, 1982, pp. 171-176.*
Sameshima et al., “XeCl Excimer Laser Annealing used to fabricate poly-Si TFT's”, Mat. Res. Soc. Symp. vol. 71, 1986, pp. 435-440.*
Sameshima et al., “XeCl Excimer Laser Annealing used to fabricate poly-Si TFT's”, Japanese Journal of Applied Physics, vol. 28, No. 10, 1989, pp. 1789-1793.*
Iwamatsu et al., “Silicon-on Sapphire MOSFETS fabricated by back-surface laser-anneal technolgy”, Electronics Letters, vol. 15, No. 25, pp. 827-828, Dec. 1979.*
Tonouchi et al., “Characterization of &mgr;c-Si:H Films Prepared by H2Sputtering”, Japanese Journal of Applied Physics, vol. 29, No. 3, pp. L385-L387 (1990).
Sun et al., “Growth Temperature of &mgr;c-Si:H Films Sputtered by Hydrogen Gas” Japanese Journal of Applied Physics, vol. 29, No. 7, pp. L1029-L1032 (1990).
SOI Structure Formation Technique, pp. 108-109, Oct. 23, 1987 (translation attached).
Kunii et al., The 29thSpring Meeting, The Japanese Society of Applied Physics and Related Societies, 4p-P-11, Apr. 1982, p. 593.
Masumo et al., “Low Temperature Polysilicon TFTs by Non-Mass-Separated Ion Flux Doping Technique”, Extended Abstracts of the 22nd(1990 International) Conference on Solid State Devices and Materials, pp. 975-978.
Sameshima et al., “XeCl Excimer Laser-Induced Amorphization and Crystallization of Silicon Films”, Extended Abstracts of the 22nd(1990 International) Conference on Solid State Devices and Materials, pp. 967-970.
Hirose, Flat Panel Display, 1991, pp. 156-159, Published Nov. 26, 1990.
Auvert et al., “Influence of CW Laser Scan Speed in Solid-Phase Crystallization of Amorphous Si Film on Si3N4/glass Substrate”, Appl. Phys. Lett. vol. 38, No. 8,
Kusumoto Naoto
Takemura Yasuhiko
Yamazaki Shunpei
Zhang Hongyong
Booth Richard
Costellia Jeffrey L.
Nixon & Peabody LLP
Semiconductor Energy Laboratory Co,. Ltd.
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