JP2003249539A - Position-detecting mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive and simple position-detecting mechanism which is operable at high temperatures so that high-temperature baking, indispensable to vacuum processing equipment, can be performed with ease. <P>SOLUTION: Wafer-processing equipment comprises a chamber, having a stage for subjecting a workpiece such as a wafer to predetermined processing in vacuum; and a chamber having a wafer transport mechanism. The wafer- processing equipment is so constituted that a wafer is transported to the stage and placed thereon by the wafer transport mechanism or a substrate on the stage, is held and transferred to another place. With respect to detection of the position of the arm of the substrate transfer mechanism, a proximity sensor is constituted of an electric wire-like sensor electrode, which is a non-active part and a moving electrode, placed on the arm which is a non-active part, and sensing operation can be made by nonactive constitution. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer transfer apparatus, and more particularly to detection of the position of a transfer arm in a vacuum container.

[0002]

2. Description of the Related Art Conventionally, since a wafer exchange operation is performed between a plurality of chambers, as shown in FIGS.
A retractable arm, a sensor that detects the rotation angle of the arm, and a sensor that detects the retracted position of the arm are provided at the arm operating point of each chamber.

When a sensor for detecting the expansion / contraction position is installed on the arm, it is necessary to pull out an electric wire for driving / detecting the sensor from the rotating arm. Alternatively, when arranging the sensors on the fixed side of the chamber body or the like, it is necessary to install the required number of sensors at locations corresponding to the respective chamber positions. Usually, in order to avoid dust generation in the chamber, these sensors often use a sensor composed of an active element such as a light emitting diode instead of the sensor utilizing a mechanical contact.

[0004]

In a vacuum container, when an active sensor is used to perform a baking operation at a temperature of a few hundreds of degrees in order to reduce the residual gas and released gas of the components, the baking is performed during the baking. Either cooled the sensor to protect it from destruction, or installed a transparent window in the chamber for external sensing. When the sensor is cooled, the sensor is not baked, and the gas released from the sensor causes a decrease in the degree of vacuum in the chamber. The detection from the outside has problems such as limitation of the detection position and installation of an expensive transparent window.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a position detecting mechanism which can operate at high temperature and which can easily perform a high temperature baking operation essential for a vacuum processing apparatus, at low cost and simply. To provide.

[0006]

To achieve the above object, the present invention has a chamber having a stage for performing a predetermined process on a workpiece such as a wafer in a vacuum, and a chamber having a wafer transfer mechanism. In a wafer processing apparatus configured to transfer and arrange a wafer to the stage by the wafer transfer mechanism or to hold a substrate on the stage and transfer it to another place, an arm portion of the substrate transfer mechanism is provided. The position detection is characterized by configuring a proximity sensor with a wire-shaped sensor electrode that is an inactive component and a movable electrode installed on an arm, and enables a sensing operation in the inactive configuration.

Here, it is preferable that the electrode is made of a material whose gas generated from the electrode does not affect the degree of vacuum required for the treatment, for example, SUS type, refractory metal type or aluminum type metal.

Further, by covering the electrodes with an insulator made of an inorganic material such as ceramics, it is possible to minimize damage to the electrodes and the control unit due to an unexpected short circuit (for example, discharge ions during sputtering). .

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a diagram showing an example in which the present invention is applied to a multi-process chamber.

A wafer transfer arm having a rotation / expansion / contraction mechanism is installed in the load lock chamber, and a sensor electrode K for detecting arm position is incorporated in the arm. Further, a sensor wire 2 for detecting an arm storage position (arm rotatable position) and a sensor wire 1 for detecting an arm extension position (wafer transfer position) are arranged in the load lock chamber.

Each of the electric wires is arranged and adjusted at a position corresponding to the arm extending / contracting position of each chamber.

The work transfer work from the input chamber to the work chamber 1 is as follows. At the arm storage position, the transfer arm is rotated to the loading chamber position, the gate valve of the loading chamber is opened, and then the transfer arm is extended to the work transfer position (sensor wire 1) in the loading chamber. Here, when the sensor electrode K and the sensor electric wire 1 come close to each other, the control unit detects the electrostatic capacitance value, thereby detecting the position of the arm and stopping the arm. Here, the work is received, and after confirming the completion of the delivery, the arm is retracted to the arm storage position. At this time, when the sensor electrode K and the sensor electric wire 2 are close to each other, the control unit detects the value of the electrostatic capacitance, thereby detecting the position of the arm and stopping the arm.

After closing the gate valve of the charging chamber, the working chamber 1 is rotated to the delivery position. The gate valve 1 of the work chamber 1 is opened, and the transfer arm is extended to the work transfer position (sensor wire 1) in the work chamber. Here, when the sensor electrode K and the sensor electric wire 1 come close to each other, the control unit detects the electrostatic capacitance value, thereby detecting the position of the arm and stopping the arm. The work is handed over here, and after confirming the completion of the delivery, the arm is retracted to the arm storage position. At this time, the sensor electrode K
When the sensor electric wire 2 comes close to the sensor electric wire 2, the control unit detects the value of the electrostatic capacity, thereby detecting the position of the arm and stopping it. Next, the gate valve 1 is closed and a series of work transfer work is completed.

The term "wafer" used in the present specification includes all kinds of wafers such as liquid crystal substrates other than the literal semiconductor wafers, which must be transported in a vacuum. Further, although the hexagonal load lock chamber is illustrated in the illustrated example, other polygonal vacuum vessels can of course be realized.

[0016]

As is apparent from the above description, according to the present invention, it is possible to inexpensively provide a position detecting mechanism which can be operated at high temperature and which can easily perform the high temperature baking work essential for the vacuum processing apparatus.
By simply providing it, it is possible to realize a vacuum container that realizes a high vacuum with less residual gas and the like.

Further, the position of the transfer arm can be detected with the minimum number of parts even in the multi-process chamber structure which has been widely used these days.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a conventional technique.

FIG. 3 is a diagram showing a conventional technique.

[Explanation of symbols]

1 Road lock room 2 Input chamber 3 Working chamber 1 4 Working chamber N 5 gate valve 6 Gate valve 1 7 Gate valve N 8 Transfer arm 9 Sensor wire 1 10 Sensor wire 2 11 Sensor electrode K 12 angle sensor 13 Arm drive shaft 14 Drive / control unit 21 load lock room 22 Input chamber

Continued front page    F term (reference) 2F063 AA03 BA30 BD15 BD17 CA31                       CA40 DA01 DA05 DD06 HA05                       HA16 PA01 PA04                 3C007 AS24 KS36 KV08 KW06 KX07                       KX19 NS12 NS13                 5F031 CA02 CA05 GA36 GA47 JA09                       JA22 MA30 NA09

Claims (5)

[Claims] 1. A chamber having a stage for performing a predetermined process on a workpiece such as a wafer in a vacuum, and a chamber having a wafer transfer mechanism, wherein the wafer transfer mechanism transfers the wafer to the stage and arranges the wafer. Or a wafer processing apparatus configured to grip a substrate on the stage and transfer it to another place, the position detection of the arm portion of the substrate transfer mechanism is a wire-like sensor electrode and arm that are inactive parts. A position detection mechanism characterized in that a movable electrode installed on the upper part constitutes a proximity sensor to enable sensing operation in an inactive structure. 2. The position detection mechanism according to claim 1, wherein the electrode is made of a material whose gas generated from the electrode does not affect the degree of vacuum required for the processing. 3. The position detecting mechanism according to claim 1, wherein the material is stainless alloy, aluminum, titanium, or an alloy thereof. 4. The position detecting mechanism according to claim 1, wherein the electrodes are covered with an insulator made of an inorganic material such as ceramics. 5. The position detection according to claim 1, wherein the wire-shaped sensor electrode is arranged in a rotation range of an arm portion of the substrate transfer mechanism to cope with position detection of the arm portion in a multi-chamber configuration. mechanism.