JPS5879734A - Table position controller detecting existence of wafer - Google Patents

Abstract

PURPOSE:To effect an accurate positioning of a wafer while eliminating noises as well as to make it possible to detect the existence of a wafer independently of the surface condition of the wafer, by a method wherein a position control is effected by means of a laser beam passed through a half-mirror, and the existence of a wafer is detected according to whether a refracted laser beam is received or not. CONSTITUTION:A part of the laser beam from a laser oscillator 20 is passed through a half-mirror 28 and is reflected by a mirror 30 obliquely mounted on a driving shaft 18. The reflected laser beam enters a reflected-laser receiver 35 having two light-receiving elements provided on the right and left of the light- receiving surface thereof. A position control is effected by rotating a table 19 through a driving device 12 until the quantities of light received by the light- receiving elements equal each other. Thereafter, the existence of a wafer on the table 19 is detected according to whether the laser beam refracted by a mirror 28 is incident on a refracted laser beam receiver 34.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wafer presence/absence determination table position control device, and in particular, to a device for determining the presence/absence of a wafer on a table in semiconductor manufacturing equipment and controlling the table position from t-1 laser oscillators. The present invention relates to a wafer presence/absence determination table position control device suitable for performing laser light determination.

A wafer presence/absence determination table position control device applied to a conventional semiconductor manufacturing apparatus will be explained with reference to FIG. M1.

In Fig. jli1, processing fi14 is provided with a laser beam passage hole lO and a window 11 as a laser passageway on the upper wall, and a shield *13 with a drive unit Wl12 inside the lower wall,
A fixed electrode plate 16 in which a laser passage hole 15 is formed at a position opposite to the laser beam passage hole 1O and the window 11, and a drive plate on which a wafer 17 is placed and which is installed inside the shield chamber 13. A table 19 rotatably connected to the device holder and a drive shaft 18 is disposed inside the device so as to face each other in the vertical direction. A laser oscillator is installed on the outside of the upper wall of the processing 1i 114, facing the laser beam passage hole 10, and similarly, a reflected laser beam receiver n connected to the wafer presence/absence determination device 5121 receives the light emitted from the laser oscillator m. The laser beam is reflected on the surface of the wafer 17, and the laser beam passing holes ts, to and the window 11t are provided on the traveling axis of the reflected laser beam. A disc with a slit is attached to the drive shaft tin installed in the shield chamber 13 so as to be able to rotate integrally with the drive shaft cover.
A photosensor 5 is attached close to the edge of the slitted disc and connected to a table position control device connected to a drive device. Further, a light absorbing body temperature is provided in the table W at the position where the wafer 17 is placed on the table 19 and on the traveling axis of the laser beam emitted from the laser oscillator section, and the high frequency power source 4 is connected to the fixed electrode plate 16 and the table 19. are connected to each.

In this case, the determination of the presence or absence of a wafer on the table w and the position control of the table (2) are performed as follows.

First, before determining the presence or absence of a wafer on the table, make sure that the wafer placement position on the table is at a predetermined position, and that the light absorber grave is on the traveling axis of the laser beam emitted from the laser oscillation 1i20. Table 19. The table 19 is controlled to an appropriate position by detecting the slit of the slitted disk device which rotates integrally with the drive shaft using the 7-point sensor 6, and appropriately rotating the drive device using the table position control device 124. Thereafter, whether the laser beam emitted from the laser oscillator is reflected by the surface of the wafer 17 or absorbed by the light absorber portion is determined by the reflected laser beam receiver 4° and the wafer presence/absence determination device [21]. The presence/absence of way I on the storage table 19 is determined.

Such a wafer presence/absence determination table position control device has the following drawbacks.

(1) The surface state of Quano® after the treatment is completed or progressed is no longer a mirror state and the laser beam is reflected diffusely, so the amount of reflected laser light received by the reflected laser light receiver becomes uneven, and therefore, The wafer presence/absence judgment device cannot properly judge the presence or absence of a wafer/S. (2) When the high frequency output from the high frequency output power source increases, the electrical signal system built into the 7 Otosensor is affected by the noise caused by this. , the table position control device cannot properly control the table position.

Note that when controlling the table position, the table position may be controlled using a laser beam emitted from a laser oscillator in order to avoid being affected by noise from the high-frequency output power source. However, in this case, one additional laser There was a drawback that an oscillator had to be installed, which increased the cost of the device.

The present invention aims to eliminate the above-mentioned drawbacks, and has a laser oscillator installed outside the processing chamber and the shield chamber, facing the shield chamber, and on the traveling axis of the laser light emitted from the laser oscillator. , a laser beam partial refractor, a laser beam passage hole drilled in the shield chamber, and a laser beam reflection mirror mounted at an angle and rotatable integrally with the drive shaft are arranged in a row, and the laser beam On the propagation axis of the refracted laser beam refracted by the partial refractor, there is a refracted laser beam passage provided in the lower wall of the treatment chamber, facing the laser beam passage hole bored in the fixed electrode plate, and an axillary refractor. a refractive laser beam passage hole bored in the table facing the laser beam passage; a laser beam passage hole bored in the fixed electrode plate; a laser beam passage provided in the upper wall of the processing chamber; A refracting laser beam receiver is provided outside facing the laser beam passageway and connected to a wafer presence/absence determination device, and is connected to a table position control device connected to a drive device. A reflected radar light receiver is installed on the traveling axis of the reflected laser light that is reflected by the laser light reflector and passed through the laser light passage hole drilled in the shield chamber, and the laser light emitted from one laser oscillator is The presence/absence of a wafer on the table can be appropriately determined using the wafer presence/absence determination device regardless of the surface condition of the Quano.
The present invention provides a table position control device for determining the presence or absence of a wafer, which allows the table position control device to properly position the table without being affected by noise from a high frequency power source.

An example of the present invention! This will be explained in Figure 2. In Fig. 2, parts of the device that are the same as those in Fig. N1 are indicated by the same reference numerals, and their explanations will be omitted.

In FIG. 2, a laser oscillator is installed outside the processing chamber 14 and the shield chamber 13, facing the shield chamber, and is installed on a fixed electrode plate 16 on the traveling axis of the laser beam emitted from the laser oscillator Zenbi. Processing 1i! facing the laser beam passage hole 15! 14, a laser beam partial refractor provided outside the shield chamber 13, for example, a half mirror row, a laser beam passage hole 4 drilled in the side wall of the shield chamber 13, and a drive shaft that rotates integrally. A laser beam reflector, for example, a mirror I, which is installed at an angle and possible, is arranged in a row, and is bored in the fixed electrode plate 16 on the traveling axis of the refracted laser beam refracted by the half mirror path. A refraction laser beam passageway provided in the lower wall of the processing chamber 14 facing the laser beam passage hole J, for example, a refraction radar beam passage hole J and a window cover, and a refraction laser beam passageway bored in the table 19 facing these. a refracted laser beam passage hole;
A radar light passage hole formed in the fixed electrode plate 16 and a laser light passage provided in the upper wall of the processing chamber 14, for example,
A laser beam passage hole 1O, a window 11, and a refractive laser beam receiver iris provided on the outside facing these and connected to the wafer presence/absence determination device 4' are arranged in a row, and a driving device side and a The traveling axis of the reflected laser beam reflected by the reflected laser beam receiver Agami t-ao connected to the connected table position control device Sae' and passed through the laser beam passage hole 4 drilled in the side wall of the shield chamber 13. is placed above.

In such a wafer presence/absence determination table position control device, determination of the presence or absence of a wafer on the table and table position control are performed as follows.

First, the position of the table is controlled. In this case, the laser beam emitted from the laser oscillation @'l:) partially passes through the half-mirror row, passes through the laser beam passage hole 4, and passes through the laser beam passing hole 4.
-30. The reflected laser beam reflected by the mirror (equipment) is tilted and installed directly in front of the drive shaft, so the axis of travel of the laser beam emitted from the laser oscillation Zenbi forms a certain angle, and the laser beam passes through the four holes. The reflected laser beam passes through and enters the receiver. At least two light-receiving elements (not shown) are installed on the left and right sides of the light-receiving surface of the reflected laser beam receiver. If the amount of reflected laser light received by each light-receiving element is different, the table position Control device[
24' rotate the drive device until the amount of reflected laser light received by each light receiving element becomes equal. In this way, the Quaeno 1 is placed at a predetermined position on the table 19. In addition, the refracted laser beam passage hole drilled in the table 19 (and the laser beam emitted from the laser oscillation Zenbi partially) is made so that the traveling axis of the refracted laser beam refracted by the -7 mirror 2B coincides with the In this case, the position of the table 19 is properly controlled.Next, the presence or absence of the wafer 17 on the table m is determined by determining whether the laser beam emitted from the laser oscillator Zenbi is This is done depending on whether or not the refracted laser beam partially refracted by the half mirror is incident on the refracted laser beam receiver. When the wafer is placed and emitting through the refracted laser beam passage hole 3!I, the refracted laser beam does not enter the refracted laser beam receiver irises. If the Quaeno-17 is not placed at the wafer placement position on the table W, the refracted laser beam will pass through the laser refracted beam passage hole, the laser beam passage hole, and the laser beam passage hole L.
Since the light passing through the light receiving surface and the window 11 enters the refracted laser light receiving device equipped with at least one light receiving element (not shown), the /% presence/absence determination device 5121' determines that there is no Waeno 17. Judgment is made clear.

As in this embodiment, a laser beam emitted from a laser oscillator and partially passed through a half mirror is reflected by a mirror that rotates integrally with the table, and the angle of incidence of the reflected laser beam on the reflected laser beam receiver is The position on the table is controlled by the fV table position control device, and the position on the table is determined by whether or not the refracted laser beam, which is the laser beam emitted from the laser oscillator partially refracted by the nof mirror, is incident on the refracted laser beam receiver. If the presence or absence of a wafer is determined by a wafer presence/absence determination device, a laser beam emitted from one laser oscillator is used, and the angle at which the reflected laser beam reaches the reflected laser beam receiver is determined by a high-frequency power source. Since it is not affected by noise, it is possible to properly control the position of the table, and since it does not use the reflected light of the laser beam on the surface of the wafer 71, it is possible to determine the presence or absence of a wafer on the table regardless of the state of the surface of the wafer 71. It can be done properly.

As described above, the present invention is applied to semiconductor manufacturing equipment, in which the presence or absence of a wafer on a table is determined by a wafer presence determination device (using laser light emitted from a laser oscillator), and the position of the table is controlled by a wafer presence determination device. In a wafer presence/absence determination table position control device performed by a control device, a laser oscillator is installed outside the processing chamber and the shield chamber facing the shield chamber, and the laser beam is partially refracted on the traveling axis of the laser beam emitted from the laser oscillator. A laser beam passing hole drilled in the shield chamber, and a laser beam reflector that can rotate integrally with the drive shaft and are mounted at an angle are arranged in a row, and the laser beam is refracted by the laser beam partial refractor. A refracted laser beam passage is provided on the lower wall of the processing chamber, facing the laser beam passage hole formed in the fixed electrode plate, on the traveling axis of the refracted laser beam, and a refracted laser beam passage is provided opposite to the refracted laser beam passage. A refracted laser beam passage hole drilled in the table, a laser beam passage hole drilled in the fixed electrode plate, a laser beam passage path provided in the upper wall of the processing chamber, and a mosquito laser beam passage hole. A refracting laser beam receiver is provided facing outside and connected to a wafer presence/absence determining device, and a reflective laser beam receiver is connected to a table position control device connected to a driving device. The refracted laser beam is provided on the axis of travel of the reflected laser beam that is reflected by a laser beam reflector and passed through a laser beam passage hole bored in the shield chamber. By controlling the position of the table and adjusting the angle of incidence of the reflected laser beam onto the receiver, the presence or absence of a wafer on the table can be determined regardless of the surface condition of the wafer. This has the advantage that the determination can be made properly and the position of the table can be controlled properly without being affected by noise from the high frequency output power source. Furthermore, since it is sufficient to install only one laser oscillator, there is also the effect of suppressing an increase in the cost of the device.

[Brief explanation of the drawing]

Figure w41 is for explaining a conventional wafer presence/absence determination table position control device M, and FIG. 1 is a cross-sectional view of a semiconductor manufacturing apparatus to which a Ueno 1 presence/absence determination table position control device according to the present invention is applied, illustrating one embodiment.

Claims (1)

[Claims] 1. In a processing chamber equipped with a shield chamber in which a laser beam passage is provided in the upper wall and a drive device is installed in the lower wall, a position opposite to the laser beam passage provided in the upper wall of the processing chamber. The wafer is placed on a table, which is an electrode plate that is vertically opposed to a fixed electrode plate in which a laser beam passage hole is bored, and that is rotatably connected to a drive device via a drive shaft. A wafer presence/absence judgment table that is applied to semiconductor manufacturing equipment that processes on-board processing, uses a laser beam emitted from a laser oscillator to determine the presence or absence of a wafer on the table using a quafer presence/absence judgment device, and uses a table position control device to control the position of the table. In the position control device, the laser oscillator is installed outside the processing chamber and the shield chamber to face the shield chamber, and on the traveling axis of the laser beam emitted from the laser oscillator, there is a laser beam partially refracted odor and a shield. A laser beam passing hole drilled in the chamber and a laser beam reflector that is rotatable integrally with the drive shaft and attached at an angle are arranged in a row, and a refracting laser that is partially refracted by the laser beam is refracted by the odor. A refracted laser beam passage provided on the lower wall of the processing chamber opposite to the laser beam passage hole formed in the fixed electrode plate on the propagation axis of the light; a refracted laser beam passage hole formed in the table, a laser beam passage hole formed in the fixed electrode plate, the laser beam passage provided in the upper wall of the processing chamber, and the laser beam passage hole. and a refracting laser beam receiver provided outside facing and connected to the wafer presence/absence determination device, and connected to the table position control device connected to the drive device. A Quafer presence/absence determination table position characterized in that a reflected laser beam receiver is provided on the traveling axis of the reflected laser beam reflected by a laser beam reflector and passed through a laser beam passage hole drilled in a shield chamber. Control device.