Coating processes – Direct application of electrical – magnetic – wave – or... – Chemical vapor deposition
Reexamination Certificate
2002-08-01
2004-08-24
Pianalto, Bernard (Department: 1762)
Coating processes
Direct application of electrical, magnetic, wave, or...
Chemical vapor deposition
C427S252000, C427S255180, C427S255280, C427S255310, C427S255320, C427S255340, C427S255360, C427S255391, C427S255393, C427S344000, C427S397700
Reexamination Certificate
active
06780476
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to formation of a dielectric thin film to be used for various electric elements such as an insulated-gate type field-effect transistor and a thin film capacitor having a laminated structure of metal-insulator-metal. More particularly, it relates to a material for use in chemical vapor deposition (CVD), a method of forming a high dielectric constant thin film by CVD and a CVD apparatus for deposition of the high dielectric constant thin film.
2. Description of the Background Art
With advancement in miniaturization of semiconductor devices, materials employed as dielectric thin films to be used for various electric elements in semiconductor devices are being changed. Recent years, requests have been made for improved storage charge density, for example. Accordingly, the use of a dielectric material having a higher dielectric constant is now under study, instead of a silicon oxide film which has conventionally been employed as a dielectric thin film.
For instance, study is being made as to employment of a high dielectric thin film in a silicon CMOS (Complementary Metal Oxide Semiconductor) logic device instead of a conventional silicon oxynitride film. This is because a next-generation MOSFET is required to ensure high mutual conductance. This is discussed by Wen-Jie Qi et al. in “Performance of MOSFETs with ultra thin ZrO
2
and Zr-silicate gate dielectrics”, 2000 Symposium on VLSI Technology Digest of Technical Papers (2000) (pp. 40-41), for example.
For the purpose of miniaturization of a high frequency device represented by a GaAs MMIC (Microwave Monolithic IC), miniaturization and integration of an electric element such as a bypass capacitor is now under study. In this study, it is considered to use a thin film capacitor in which a high dielectric constant thin film is employed instead of a conventional silicon nitride film or the like. This is discussed by S. Nagata et al. in “A GaAs MMIC Chip-Set for Mobile Communications Using On-Chip Ferroelectric Capacitors”, 1993 IEEE International Solid-State Circuits Conference (1993) (p. 285), for example.
In order to improve storage charge density of a memory cell in a memory device such as DRAM (Dynamic Random Access Memory), the use of a memory cell capacitor using a high dielectric constant thin film is now under study, instead of a stacked structure of a conventional silicon oxide film and a conventional silicon nitride film.
As a high dielectric constant thin film suitable for these applications, attention is now being directed particularly to a dielectric film including a silicate compound for its high chemical stability. The aforementioned document by Wen-Jie Qi et al., for example, shows that, in the case where a ZrSiO
4
film as a kind of a silicate compound is directly formed on a silicon substrate, heat treatment at about 700° C. does not cause significant mutual diffusion between the silicon substrate and the ZrSiO
4
film. The document also ascertains the operation of a MOSFET in which an ultra thin ZrSiO
4
film is used.
As has been described, a silicate compound is useful for a high dielectric constant film used for various electric elements integrated in a semiconductor device. Among methods of forming such a silicate compound, a sputtering method, a method utilizing heat reaction between ZrO
2
and Si and the like are in the mainstream under present circumstances.
In an application of a silicate compound to the actual manufacture of LSI, however, it is desirable to form a high dielectric constant film by CVD in view of smoothness and coverage of a step difference in a finished film.
Nevertheless, materials suitable for achieving film deposition of good quality or combination of such materials in forming a high dielectric constant film including a silicate compound have not been clarified. Further, it has not been clarified what treatment should be given to films deposited by CVD to obtain a high dielectric constant film of good quality.
Particularly, in film formation using a plurality of materials, reaction between the materials often causes generation of dust in the vapor phase, adhesion of deposits to a supply conduit and the like. Therefore, there arise problems such as that the supply of materials becomes unstable, resulting in frequent occurrence of variations in the deposition speed each time of film formation. There are no findings at the moment that can contribute to solution of such instability in film formation of a silicate compound which is a high dielectric constant film.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a liquid material for CVD, a method of forming a film by CVD and a CVD apparatus, capable of achieving film formation of a silicate compound of good quality.
An aspect of the present invention is directed to a method of forming a film using chemical vapor deposition, wherein a liquid material for chemical vapor deposition including an organometallic compound, a siloxane compound and an organic solvent for dissolving the organometallic compound and the siloxane compound is vaporized to form one of a film and a precursor film.
The method allows stable deposition of a good quality film in film formation of a silicate compound using CVD. Further, film formation using the liquid material is suitable for the manufacture in light of the ease of material supply.
These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
REFERENCES:
patent: 367745 (1887-08-01), Durst
patent: 677317 (1901-06-01), MacDonald
patent: 5249554 (1993-10-01), Tamor et al.
patent: 6060406 (2000-05-01), Alers et al.
patent: 6563182 (2003-05-01), Horikawa
patent: 6566147 (2003-05-01), Basceri et al.
patent: 7-193147 (1995-07-01), None
patent: 8-255792 (1996-10-01), None
patent: 11-135774 (1999-05-01), None
patent: 11-330070 (1999-11-01), None
patent: 2000-12840 (2000-01-01), None
patent: 2000-219970 (2000-08-01), None
patent: 3095727 (2000-10-01), None
W.J. Ol, et al., 2000 Symposium on VLSI Technology Digest of Technical Papers, pps. 40-41, “Performance of MOSFETs With Ultra Thin ZrO2And Zr Silicate Gate Dielectrics,” 2000, no month avail.
S. Nagata, et al., 1993 IEEE International Solid-State Circuits Conference, pp. 285, “A GaAs MMIC Chip-Set For Mobile Communications Using On-Chip Ferroelectric Capacitors,” 1993, no month avail.
Pianalto Bernard
Renesas Technology Corp.
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