This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-190594, filed Jun. 26, 2000, the entire contents of which are incorporated herein by reference.
The present invention relates to a single-substrate-processing apparatus for performing a semiconductor process, such as oxidation, diffusion, film formation, or annealing. The term xe2x80x9csemiconductor processxe2x80x9d used herein includes various kinds of processes which are performed to manufacture a semiconductor device or a structure having wiring layers, electrodes, and the like to be connected to a semiconductor device, on a target substrate, such as a semiconductor wafer or an LCD substrate, by forming semiconductor layers, insulating layers, and conductive layers in predetermined patterns on the target substrate.
In the process of manufacturing semiconductor devices, several types of heat-processing apparatuses are used for subjecting target substrates, such as semiconductor wafers, to a semiconductor process, such as oxidation, diffusion, film formation, or annealing. A single-substrate-processing apparatus, which handles wafers one by one, is known as one of these heat-processing apparatuses. The single-substrate-processing apparatus generally includes an airtight process chamber, and a worktable disposed in the process chamber for mounting a target substrate.
Jpn. Pat. Appln. KOUKOKU Publication No. 6-28258 and Jpn. Pat. Appln. KOKAI Publication No. 10-189490 disclose a structure in which a ceramic worktable with a built-in resistance heater is supported by a ceramic pedestal. Since the worktable and the pedestal are made of a ceramic, they can provide a heat source, which withstands a high temperature of, e.g., 500xc2x0 C. or more, while not contaminating a target substrate, such as a wafer.
However, the present inventors have found that the structure described above causes the following problems in relation to the installation of the worktable in the process chamber. First, ceramics do not have a high mechanical strength, and thus connected portions of the pedestal tend to break easily. In addition, when the pedestal is attached to or detached from the process chamber, the worktable is an obstacle to the operation, thereby deteriorating ease of use.
An object of the present invention is to provide a single-substrate-processing apparatus for a semiconductor process, which allows a worktable to be installed in a process chamber with a high mechanical strength, and also allows the worktable to be easily attached and detached.
According to a first aspect of the present invention, there is provided a single-substrate-processing apparatus for performing a semiconductor process, comprising:
an airtight process chamber;
a supply section configured to supply a process gas into the process chamber;
an exhaust section configured to vacuum-exhaust the process chamber;
a worktable having a mount face configured to horizontally support a target substrate within the process chamber, the worktable having a table body consisting essentially of a ceramic;
a heater configured to heat the target substrate through the mount face, the heater comprising a resistance heater embedded in the table body;
a pedestal configured to stand upright in the process chamber and support the worktable, the pedestal having a pedestal body consisting essentially of a ceramic, and the pedestal body having a flange at a bottom end;
a flange holder configured to attach the flange to a bottom of the process chamber, the flange holder comprising an upper frame that pushes the flange toward the bottom of the process chamber; and
a fixing member configured to detachably fix the flange holder to the bottom of the process chamber from outside the process chamber, the fixing member penetrating the bottom of the process chamber and engaging with the flange holder.
According to a second aspect of the present invention, there is provided a single-substrate-processing apparatus for performing a semiconductor process, comprising:
an airtight process chamber having a bottom provided with an opening formed therein,
a supply section configured to supply a process gas into the process chamber;
an exhaust section configured to vacuum-exhaust the process chamber;
a worktable having a mount face configured to horizontally support a target substrate within the process chamber, the worktable having a table body consisting essentially of a ceramic;
a heater configured to heat the target substrate through the mount face, the heater comprising a resistance heater embedded in the table body;
a pedestal configured to stand upright in the process chamber and support the worktable, the pedestal extending from the worktable to the bottom of the process chamber and having an internal hollow portion communicating with the opening, the pedestal having a pedestal body consisting essentially of a ceramic, and the pedestal body having a flange at a bottom end;
an electrical cable connected to the resistance heater and led out to an outside of the process chamber through the internal hollow portion and the opening;
a flange holder configured to attach the flange to a bottom of the process chamber, the flange holder comprising an upper frame that pushes the flange toward the bottom of the process chamber, and a lower frame disposed between the upper frame and the bottom of the process chamber, such that the flange is sandwiched between the upper and lower frames, and the upper frame comprising a plurality of parts separated from each other by radial separating lines; and
a fixing member configured to detachably fix the flange holder to the bottom of the process chamber from outside the process chamber, the fixing member penetrating the bottom of the process chamber and engaging with the flange holder, the fixing member comprising a plurality of fixing bolts, and the flange holder having a plurality of female thread portions that respectively engage with the fixing bolts.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.