Coating apparatus – Gas or vapor deposition – With treating means
Reexamination Certificate
2000-06-19
2001-05-08
Mills, Gregory (Department: 1763)
Coating apparatus
Gas or vapor deposition
With treating means
C118S7230AN, C156S345420
Reexamination Certificate
active
06227141
ABSTRACT:
TECHNICAL FIELD
This invention relates to RF powered plasma enhanced chemical vapor deposition reactors and methods of effecting plasma enhanced chemical vapor deposition.
BACKGROUND OF THE INVENTION
Semiconductor processing often involves the deposition of films or layers over or on a semiconductor substrate surface which may or may not have other layers already formed thereon. One manner of effecting the deposition of such films or layers is through chemical vapor deposition (CVD). CVD involves a chemical reaction of vapor phase chemicals or reactants that contain the desired constituents to be deposited on the substrate or substrate surface. Reactant gases are introduced into a reaction chamber or reactor and are decomposed and reacted at a heated surface to form the desired film or layer.
There are three major CVD processes which exist and which may be utilized to form the desired films or layers. These are: atmospheric pressure CVD (APCVD), low pressure CVD (LPCVD), and plasma enhanced CVD (PECVD). The former two processes (APCVD and LPCVD) are characterized by their pressure regimes and typically use thermal energy as the energy input to effect desired chemical reactions. The latter process (PECVD) is characterized by its pressure regime and the method of energy input.
In PECVD systems, rather than relying on thermal energy to initiate and sustain chemical reactions, RF-induced glow discharge is used to transfer energy to the reactant gases. Such allows the substrate to remain at a lower temperature than the APCVD and LPCVD systems. Lower substrate temperatures are desirable in some instances because some substrates do not have the thermal stability to accept coating by the other methods. Other desirable characteristics include that deposition rates can be enhanced and films or layers with unique compositions and properties can be produced. Furthermore, PECVD processes and systems provide other advantages such as good adhesion, low pinhole density, good step coverage, adequate electrical properties, and compatibility with fine-line pattern transfer processes.
One problem, however, associated with deposition processing including PECVD processing stems from non-uniform film or layer coverage which can result especially in high aspect ratio topographies. For example, a problem known as “bread-loafing” or cusping can typically occur in deposition processing. Such normally involves undesirable non-uniform build-up of deposited material forming what appear as key hole spaces between features on a substrate. One prior art solution has been to conduct multiple depositions of very thin layers with intervening plasma etching treatments. The intervening plasma etching serves to remove or cut away the cusps to form a more uniformly applied layer. Thereafter, repeated depositions and etchings are conducted until the desired coverage is achieved. It is desirable to improve upon the quality of film or layer deposition in PECVD processes and reactors.
Another problem associated with PECVD reactors stems from the use of the high frequency RF power which is utilized to develop the desired plasma environment. Such high frequency RF power typically develops a high frequency power loop which tends to interfere in an undesirable way with the operation of other reactor components. For example, often times a thermocouple link is established with one or more of the electrodes to monitor the subject electrode temperature during processing operations. The high frequency loop can and often does render the readings taken by the thermocouple link inaccurate. Thus, it is desirable to improve upon the manner in which high frequency RF power is utilized in PECVD reactors.
This invention grew out of concerns associated with improving PECVD processing systems and methods. This invention also grew out of concerns associated with improving the advantages and characteristics associated with PECVD systems, including those advantages and characteristics mentioned above.
SUMMARY OF THE INVENTION
Plasma enhanced chemical vapor deposition (PECVD) reactors and methods of effecting the same are described. In a preferred implementation, a PECVD reactor includes a processing chamber having a first electrode therewithin. A second electrode is disposed within the chamber and is configured for supporting at least one semiconductor workpiece for processing. A first RF power source delivers RF power of a first frequency to the first electrode. A second RF power source delivers RF power of a second frequency to the second electrode. Preferably the first and second frequencies are different from one another, and even more preferably, the first frequency is greater than the second frequency. The preferred reactor includes a thermocouple which provides temperature information relative to one of the electrodes. According to a preferred implementation, the power loop developed by the first RF power source is grounded interiorly of the chamber in a manner which reduces if not eliminates interference with other reactor components, including the thermocouple.
REFERENCES:
patent: 4585516 (1986-04-01), Corn et al.
patent: 5039388 (1991-08-01), Miyashita et al.
patent: 5052239 (1991-10-01), Vakerlis et al.
patent: 5102523 (1992-04-01), Beisswenger et al.
patent: 5147493 (1992-09-01), Nishimura et al.
patent: 5230931 (1993-07-01), Yamazaki et al.
patent: 5260236 (1993-11-01), Petro et al.
patent: 5261962 (1993-11-01), Hamamoto et al.
patent: 5272417 (1993-12-01), Ohmi
patent: 5433786 (1995-07-01), Hu et al.
patent: 5439524 (1995-08-01), Cain et al.
patent: 5468296 (1995-11-01), Patrick et al.
patent: 5567267 (1996-10-01), Kazama et al.
patent: 5605637 (1997-02-01), Shan et al.
patent: 5607542 (1997-03-01), Wu et al.
patent: 5656123 (1997-08-01), Salimian et al.
patent: 5665167 (1997-09-01), Deguchi et al.
patent: 5716534 (1998-02-01), Tsuchiya et al.
patent: 5863339 (1999-01-01), Usami
patent: 5865937 (1999-02-01), Shan et al.
patent: 5900103 (1999-05-01), Tomoyasu et al.
patent: 5919332 (1999-07-01), Koshiishi et al.
patent: 5942075 (1999-08-01), Nagahata et al.
patent: 0 552 491 A1 (1993-07-01), None
patent: 0 641 150 A1 (1995-03-01), None
patent: 0 678 903 A1 (1995-10-01), None
patent: 0 686 708 A1 (1995-12-01), None
patent: 742 577 A2 (1996-11-01), None
patent: 776 991 A1 (1997-06-01), None
patent: 831 679 A1 (1998-03-01), None
patent: 2 663 806 (1991-12-01), None
patent: 5-175163 (1993-07-01), None
patent: WO 89/02695 (1989-03-01), None
patent: WO 95/32315 (1995-11-01), None
patent: WO 98/32154 (1999-11-01), None
Sandhu Gurtej S.
Sharan Sujit
Smith Paul
Hassanzadeh P.
Micro)n Technology, Inc.
Mills Gregory
Wells, St. John, Roberts Gregory & Matkin P.S.
LandOfFree
RF powered plasma enhanced chemical vapor deposition reactor... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with RF powered plasma enhanced chemical vapor deposition reactor..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and RF powered plasma enhanced chemical vapor deposition reactor... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2532837