Coating apparatus – Gas or vapor deposition – Running length work
Reexamination Certificate
2000-07-26
2002-09-10
Dang, Thi (Department: 1763)
Coating apparatus
Gas or vapor deposition
Running length work
C118S7230ER, C427S569000
Reexamination Certificate
active
06447612
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a film-forming apparatus for forming a functional deposited film on a substrate. The present invention also relates to a vacuum processing apparatus and a vacuum processing method for vacuum-processing an object. Still more particularly, the present invention relates to a roll-to-roll type continuous film-forming apparatus having a plurality of vacuum chambers communicated with each other, which enables one to continuously form a functional deposited film on an elongated substrate such as a substrate web by continuously transporting the substrate in the longitudinal direction to sequentially pass through said plurality of vacuum chambers while forming a desired functional deposited film in each vacuum chamber. The film-forming apparatus is suitable particularly for continuously forming a semiconductor element such as a photovoltaic element including a solar cell.
2. Related Background Art
For the continuous formation of a functional deposited film on a substrate which is suitable for use in the production of a photovoltaic element including a solar cell, there are a number of proposals in which a plurality of deposition chambers are provided such that they are communicated with each other, and an elongated substrate (a substrate web) is continuously moved to sequentially pass through said plurality of deposition chambers while forming a desired functional deposited film on the substrate by each deposition chamber. For instance, U.S. Pat. No. 4,400,409 (hereinafter referred to document 1) and U.S. Pat. No. 5,510,151 (hereinafter referred to as document 2) disclose a method and an apparatus for continuously forming a photovoltaic element on an elongated substrate, i.e., a substrate web by way of a roll-to-roll film-forming process. Particularly, these documents 1 and 2 describe that using a film-forming apparatus comprising a plurality of vacuum vessels capable of being vacuumed and a plurality of film-forming chambers having a discharge region each provided in one of said plurality of vacuum vessels wherein said plurality of vacuum vessels are communicated with each other, a substrate web having a desired width is transported in the longitudinal direction and along a prescribed pathway for the substrate web to be moved to sequentially pass through the film-forming chambers each provided in the vacuum vessel while forming a desired deposited film on the substrate web by each film-forming chamber, whereby an element having a semiconductor junction can be continuously formed on the substrate web. Specifically, the film-forming apparatus described in documents 1 and 2 is structured such that the vacuum vessels each having the film-forming chamber provided therein can be evacuated to maintain their inside at a reduced pressure and the substrate web can transported while being held so as to serve as an upper wall of each film-forming chamber. In each of the film-forming chambers each provided in one of the vacuum vessels, a raw material gas and an electric power(such as a high frequency power) for exciting or decomposing said raw material gas are introduced therein to form a desired deposited film on the substrate web by way of plasma CVD, sputtering or the like.
Incidentally, in the film-forming apparatus comprising a plurality of vacuum vessels capable of being vacuumed and a plurality of film-forming chambers having a discharge region each provided in one of said plurality of vacuum vessels wherein said plurality of vacuum vessels are communicated with each other, a substrate web having a desired width is transported in the longitudinal direction and along a prescribed pathway for the substrate web to be moved to sequentially pass through the film-forming chambers each provided in the vacuum vessel while forming a desired deposited film on the substrate web by each film-forming chamber, it is known, as disclosed, for instance, in Japanese Unexamined Patent Publication No. 181005/1977, that each film-forming chamber is provided with a slit-like opening at each of its opposite sides through which the substrate web is moved, and an opening-adjusting member having a slit which allows the substrate web to pass through is provided at the slit-like opening for determining the width of the slit-like opening, wherein the slit-like opening provided at one film-forming chamber is communicated with a passage way for the substrate web which is communicated with another slit-like opening provided at the other film-forming chamber which is situated adjacent to said film-forming chamber. The opening-adjusting member also serves to restrict the extent of a region for the substrate web to be exposed to a plasma or the like in the film-forming chamber, namely, the area of a film-forming region in the film-forming chamber in order to control the thickness or property of a film deposited on the substrate web in the film-forming chamber.
The opening-adjusting member further serves to prevent a raw material gas and excited species thereof and a high frequency power for exciting said raw material gas in the film-forming chamber from being leaked outside the film-forming chamber.
In the present invention, attention is focused on the functions of the opening-adjusting member to allow the substrate web to pass therethrough into the film-forming chamber while preventing the raw material gas, the excited species thereof, and the high frequency power in the film-forming chamber from being leaked outside the film-forming chamber.
By the way, the height of the slit of the opening-adjusting member, that is, the clearance of the opening-adjusting member is usually extremely narrowed to an extent of several millimeters. In order to improve the characteristics of an element to be formed on the substrate web, it is necessary to adequately change particularly the inner pressure in each film-forming chamber upon film formation, and in the case where the electric power introduced into a given film-forming chamber is increased, it is necessary to have a due care so that the plasma is confined within the film-forming chamber. In this connection, it is desired that the slit-like opening is made have a cross section which is as smaller as possible and its length in the transportation direction of the substrate web is prolonged.
As the substrate web, it is usually use a substrate web which has a thickness which is sufficiently thin with respect to the width and a sufficiently long length and which has a substantially flat surface at room temperature where no external pressure is applied thereon. In the case where the film-forming chamber is shaped in a rectangular form whose upper side is open while maintaining the substrate web in a plane state by applying a prescribed tensile force thereto in the longitudinal direction, the substrate web is transported such that it serves to establish a upper wall for the film-forming chamber.
Incidentally, the above described film-forming technique have such disadvantages as will be described below.
That is, a prescribed heater is provided in each film-forming chamber in order to heat the substrate web to a desired temperature. Because of this, there is an occasion in that the substrate web heated by the heater is spontaneously deformed in a bow or wave form to have a flexture.
As one of the causes of occurring such flexture for the substrate web, there is known a situation such that in the case where the substrate web which is transported in the longitudinal direction of the film-forming apparatus is heated in the film-forming chamber, the substrate web is sometimes partially thermally expanded in its width direction, and other portion of the substrate web is shrunk by being cooled, where displacement is occurred at the substrate web in a direction perpendicular to the surface of the substrate web, whereby a portion of the substrate web which corresponds the thermally expanded portion in the width direction is relaxed and as a result, the substrate web is deformed as above described. As another cause,
Hori Tadashi
Kanai Masahiro
Koda Yuzo
Moriyama Koichiro
Canon Kabushiki Kaisha
Dang Thi
Fitzpatrick ,Cella, Harper & Scinto
LandOfFree
Film-forming apparatus for forming a deposited film on a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Film-forming apparatus for forming a deposited film on a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Film-forming apparatus for forming a deposited film on a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2867328