Substrate processing apparatus and substrate processing method

Abstract

A wafer processing apparatus includes a common path, extending in a Y-axis direction, in which one wafer or a plurality of wafers are conveyed, a plurality of process units stacked on both sides of the common path to constitute multi-stage structures, a main handler moved in the common path in the Y-axis direction and rotated about a Z axis at an angle theta to load / unload the wafer into / from the process units, an arm section arranged to move in the main handler in the Z-axis direction, a plurality of holding arms arranged in the arm section to constitute a multi-stage structure so as to respectively hold the wafers, each holding arm being advanced and retreated on an X-Y plane from the arm section, an optical sensor, arranged in the arm section, for detecting a holding state of the wafer in each of the plurality of holding arms, and a controller for controlling an operation of the main handler, an operation of the arm section, and operations of the plurality of holding arms on the basis of a detection result from the optical sensor, wherein the controller advances or retreats each holding arm while operating at least one of the main handler and the arm section, and causes the optical sensor to detect the holding state of the wafer by each holding arm before the holding arm reaches a corresponding one of the process units.

Description

BACKGROUND OF THE INVENTION1. Field of the InventionThe present invention relates to substrate processing apparatus and a substrate processing apparatus for processing a substrate such as a semiconductor wafer.2. Description of the Related ArtIn a photolithography process in manufacturing a semiconductor device, a resist coating process for coating a resist on a wafer and a developing process for developing a coated resist after an exposure process. These processes are simultaneously performed by using a composite process system described in, e.g., U.S. Pat. No. 5,339,128. This system comprises a main handler for conveying a wafer, and is designed such that a wafer W is loaded by the main handler from a cassette station into a process section, the wafer W are exchanged between process chambers in the process section, and the above processes are performed.A conventional handler has an arm section driven by three axes (Y axis, Z axis, and .theta. rotation axis), and the arm section a ...

AI Technical Summary

Benefits of technology

It is an object of the present invention to provide a substrate processing apparatus and a substrate processing method in which a substrate can be conveyed as a whole within a short time without causing an excessive load to act on each drive mechanism to increase a throughput and to suppress generation of particles.

In each of all the operations, a time required to convey a wafer is shorter than that in the conventional sequential operations. A whole convey time can be adjusted to a longer one of a time required for Z-axis direction moving and a time required for .theta. rotation. In this manner, the wafer can be rapidly conveyed at a rated moving speed within a time shorter than a time required in the conventional operation. Furthermore, an amount of particle generation can be suppressed.

When the holding arms are advanced and retreated while the main handler moves in the Z-axis direction, it can be detected and checked whether the substrate is held by the holding arms. On an early stage before the next step, so that held wafer can be checked in advance. A trouble can be prevented.

In the process (b), a holding state of the substrate by the holding arm is preferably changed depending on the type of a process in one process unit, and a convey speed at which the substrate is conveyed from the process unit into another process unit is preferably changed. In the step (b), an acceleration and a deceleration at which the substrate is moved is preferably changed depending on a moving distance of the substrate. In addition, in the step (c), when the substrate is transferred from the holding arm onto a mounting table in the process unit, the downward moving speed of the arm section is preferably decreased.

Problems solved by technology

However, since the 4-axis drive operations in the X-axis direction, Y-axis direction, Z-axis direction, and .theta.-rotation-axis direction are independently performed in the conventional main handler, the speed of the main handler operation is limited to a certain speed.

Therefore, a time from when the main handler reaches a target point to when the main handler receive a wafer is too long so that it is very difficult to increase the throughput.

In addition, when each drive system employs a high-speed drive mechanism to more increase the operation of the main handler, an excessive load acts on the mechanism, its durability and reliability may be degraded.

In addition, when the operation speed of each drive system is increased, a noticeable amount of particle is generated, the wafer is contaminated by attaching particle on the wafer, and a yield may be decreased.

When the residual resist is attached to the holding arms of the main handler, the wafer W is easily removed from the holding arms, and the wafer W cannot be smoothly conveyed.

In a process using a resist solution having a low viscosity, it may be impossible to perform a side rinse process.

In this manner, the wafer is contaminated by the particles, and a production yield is decreased.

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