KR20190070266A - Work detection apparatus, film formation apparatus and work detection method - Google Patents

Abstract

The objective of the present invention is to provide a work detecting apparatus capable of detecting an abnormality in a position of a work having a warpage or the like by a common detection means without depending on the surface properties of the work, a film forming apparatus and a work detecting method. The work detecting apparatus comprises: a first setting unit (42) for setting a first area (S1) of a predetermined size; a second setting unit (43) for setting a second area (S2) which is larger than the first area (S1) and in which the first area (S1) is entirely filled; a detecting unit (44) for detecting a value corresponding to an area of a region in which an image of reflected light from a photographed wafer (W) housed in a holder (H) overlaps a region between the first area (S1) and the second area (S2); and a determining unit (45) for determining whether there is an abnormality in the position of the wafer (W) with respect to the holder (H) based on whether or not the value detected by the detecting unit (44) exceeds a threshold value.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work detection apparatus, a film formation apparatus,

The present invention relates to a work detection apparatus, a film formation apparatus, and a work detection method.

A plurality of films may be laminated and formed on a work such as a wafer or a glass substrate in a manufacturing process of various semiconductor devices. As a film forming apparatus for forming a plurality of films, there is a so-called multi-chamber type film forming apparatus provided with a plurality of depressurizable chambers. In each chamber, a target made of a film forming material is disposed. An inert gas is introduced into the chamber, a voltage is applied to the target to plasmaize the inert gas to generate ions, and the ions are collided with the target. The film formation is performed by sputtering in which particles of the material protruding from the target are deposited on the work.

Patent Document 1: JP-A-2008-244078

The work for film formation by sputtering is transported to the film formation apparatus while being placed in the holder. The position and the inclination of the work disposed in the holder may not be constant but may be pushed out of the holder. In a work having a large degree of pushed out from the holder, the distance between the target and the plasma is not constant within the film formation plane, and uniform film formation processing can not be performed.

In order to cope with this, a method of detecting the position of the work, such as the outer circumference, by means of a laser sensor or the like, and judging an abnormality of the position from the displacement from the reference position is considered. However, the workpiece has different surface properties depending on its material. For example, semiconductor wafers differ in light transmittance or reflectance depending on whether the material is silicon (Si), silicon carbide (SiC), whether a pattern is formed, whether or not a film is formed, and the like. If a plurality of types of wafers having different surface properties are to be detected by, for example, a common sensor, a value such as sensitivity optimum for detection of each wafer differs, and therefore, the value must be changed each time the wafer is changed. In addition, there are cases where it is difficult to know a value such as sensitivity optimum for detection of each wafer. In order to cope with this problem, it is not practical to provide a sensor suitable for each of the wafers having different surface properties, because the cost becomes high.

Therefore, an arbitrary image reflected on the wafer is picked up by the camera, and the center position of the image of the picked-up arbitrary image is obtained. From this center position and the shift amount of the center position which is a preset reference, (See Patent Document 1).

However, a very thin wafer exists. For example, in the field of power devices, an electronic circuit such as a MOS-FET is formed in advance in a power device field, and then the aluminum is processed into a very thin film by cutting the back surface, do. Such a thin wafer may be warped or distorted. Since the manner of warping and warping is different for each wafer, even if the wafer is of the same diameter, or even if the wafer is in the correct position, the center position is not constant. For this reason, it is not easy to set the center position of the reference wafer, and it is difficult to determine the shift amount based on the set center position.

The object of the present invention is to provide a work detection device, a film formation apparatus, and a work detection method capable of detecting an abnormality in the position of a work having a warp or the like without being influenced by the surface property of the work by the common detection means do.

In order to achieve the above object, a work detection apparatus of the present invention comprises a first setting section for setting a first area of a predetermined size, and a second area which is larger than the first area and into which the first area is entirely set A detector configured to detect a value corresponding to an area of an area where the image of the reflected light from the work received and held in the holder overlaps with the area between the first area and the second area; And a determination unit that determines whether or not the position of the work with respect to the holder is abnormal based on whether or not the value detected by the detection unit exceeds a threshold value.

The first area may be of such a size that an image of reflected light from a work at a normal position accommodated in the holder enters. The first region and the second region may be concentric.

An input unit for instructing the setting of the first area by the first setting unit; and the second setting unit may set the second area in accordance with the setting of the first area by the input unit.

And a display unit for displaying information corresponding to the area. The display unit may display information indicating the abnormality.

A single light source for irradiating the work with light and an imaging section for imaging the reflected light from the work.

Further, the film forming apparatus of the present invention has the film forming section that performs film forming on the work detection device and a work determined by the work detection device to be abnormal in position.

According to the present invention, there is also provided a method of detecting a work, comprising: a first setting process of setting a first area of a predetermined size; and a second setting process of setting a second area larger than the first area, A detection process of detecting a value corresponding to an area where the image of the reflected light from the work overlaps with an area between the first area and the second area; Based on whether the value exceeds a threshold value or not, whether or not the position of the work with respect to the holder is abnormal.

According to the present invention, it is possible to detect an abnormality in the position of a workpiece having a warp or the like without being influenced by the surface property thereof by the common detecting means.

Fig. 1 is a plan view (A) and a side view (B) schematically showing a wafer with warpage.
2 is a plan view (A) and AA sectional view (B) showing a holder for accommodating a wafer.
3 is a plan view schematically showing the configuration of the film forming apparatus according to the embodiment.
Fig. 4 is a cross-sectional view taken along line BB of Fig. 3, which schematically shows the structure of the detection mechanism.
5 is a cross-sectional view showing the wafer receiving state of the detection mechanism in Fig.
Fig. 6 is a cross-sectional view showing a wafer arrangement state of the detection mechanism of Fig. 4;
7 is a bottom view showing a camera and a light source of the imaging unit.
8 is an explanatory view showing an example of a display screen of the reflected light image, the first area, and the second area.
9 is a cross-sectional view schematically showing the structure of a deposition chamber.
10 is a cross-sectional view showing a holder arrangement state of the deposition chamber shown in Fig.
11 is a block diagram showing a control device.
12 is an explanatory view showing the size of the image of the reflected light, the first area, and the second area.
13 is an explanatory view showing an aspect of the position of the wafer with respect to the holder.
Fig. 14 is an explanatory diagram showing an aspect of stranding of a wafer with respect to a holder. Fig.
15 is a graph showing the relationship between the landing amount and the detection value.
16 is a flowchart showing the processing procedure of the embodiment.

Embodiments of the present invention will be described in detail with reference to the drawings.

(wafer)

In the present embodiment, an example of using a semiconductor wafer W as shown in Fig. 1 is described as a work to be film-formed. A circuit is formed on the surface of the wafer W before the film forming process, and the back surface is ground. In recent years, due to the tendency of thinning due to high integration, the wafer W is ground to a level of several tens of micrometers in thickness. As described above, since the wafer W is formed to be very thin, warpage and warpage occur. In the film forming step, a film is formed on the ground surface.

(holder)

In the present embodiment, a holder H is used as a member on which the wafer W to be formed is placed, as shown in Fig. The holder H is a bottomed cylindrical member having a rectangular cross section cut by the A-A cut surface and has a receiving portion Hs sized to receive the wafer W therein. At the bottom of the holder H, an opening H0 having a diameter smaller than that of the wafer W is formed. Therefore, the outer periphery of the surface of the wafer W can be supported by the bottom of the peripheral edge of the opening H0. The opening H0 is of a size that allows the lifting plate 232 and the lifting shaft 233 to be inserted and ejected (see Fig. 5).

(Film forming apparatus)

(summary)

As shown in Fig. 3, the film forming apparatus 100 of the present embodiment has a standby loader 200, a film forming unit 300, and a control device 400. Fig.

The waiting loader 200 is a constituent part for placing the wafer W in the holder H and bringing the wafer W into the film forming section 300. The film forming unit 300 is a component that performs film formation by sputtering on the wafer W placed on the holder H. [ The control device 400 is an apparatus for controlling each section of the film formation apparatus 100. [ The details of each part of the film forming apparatus 100 will be described below.

(Standby loader)

The standby loader 200 has a holder supply section 210, a wafer supply section 220, and a detection mechanism 230. The holder supplying section 210 has a holder cassette and a carrying arm, not shown, in which a plurality of holders H are stacked and housed. The wafer supply unit 220 has a wafer cassette and a transfer arm in which a plurality of wafers W are stacked and accommodated. The detection mechanism 230 is a component for capturing an image of the wafer W placed on the holder H. [

The holder H taken out by the carrying arm from the holder cassette of the holder supplying section 210 is set on the detecting mechanism 230. [ The wafer W taken out of the wafer cassette of the wafer supplying section 220 is placed in the receiving section Hs of the holder H set on the detecting mechanism 230. [ The wafer W is carried into the film forming unit 300 while being placed on the holder H by a transfer arm (not shown).

4, the detecting mechanism 230 has a supporting table 231, a lifting plate 232, an elevating shaft 233, a strut 234, and an image pickup unit 235. As shown in Fig. The support table 231 is a base on which the holder H is disposed. The support 231 is provided with an opening 231a corresponding to the opening H0 of the holder H. [ The lift steel plate 232 is a plate-like member that can move in the vertical direction through the opening 231a and the opening H0 from the lower side of the support table 231.

The lifting shaft 233 is a rod-shaped member whose one end is connected to the lifting plate 232. The other end of the lifting shaft 233 is connected to a driving source (not shown). The driving source moves the lifting shaft 233 up and down. As the driving source, for example, an air cylinder can be used.

5, the lifting plate 232 which has entered from the opening 231a of the support table 231 and the opening H0 of the holder H and is further lifted by the lifting shaft 233 is lifted up by the holder H, The wafer W is transferred to the upper side of the wafer W. 6, the lifting plate 232 is lowered to accommodate the wafer W in the accommodating portion Hs of the holder H. As shown in Fig. The column 234 has two columnar members installed upright from both sides of the support table 231 so as to be parallel to the diameter of the holder H and to be attached with a beam arranged over the support table 231 Member.

The image pickup section 235 has a camera 21 and a light source 22. As shown in Fig. 7, the camera 21 has an image pickup device having an optical member such as a lens and an image sensor as a light receiving element such as CMOS or CCD, and outputs a signal corresponding to light detected by the light receiving element through the optical member to be. The light source 22 is an illumination device such as an LED that irradiates light onto the wafer W. In the present embodiment, as shown in Fig. 7, one light source 22 is provided at a position adjacent to the optical member of the camera 21. Fig. The light source 22 may illuminate the whole wafer W, but it is not necessarily required to illuminate the entire wafer W. For example, in the present embodiment, light having a diameter of about 10 mm is irradiated onto the wafer W.

The image of the reflected light from the wafer W picked up by the camera 21 is displayed on the screen of the display unit 49, which will be described later, as shown in Fig. The image of the reflected light from the wafer W refers to the reflected light from the image formed by detecting the light reflected by the light source 22 from the light source 22 and reflected by the light receiving element or the outline corresponding to the outer edge of the wafer W As shown in FIG. Hereinafter, an image of the reflected light from the wafer W is referred to as a reflected light image Sw. Both the total reflection, the transparent and the semitransparent wafers W, the outline corresponding to the outer edge of the reflected light can be picked up with brightness that can be discriminated from the background. Therefore, an area having a light quantity greater than a preset threshold value can be extracted as the image Sw of the reflected light.

(Film forming portion)

3, the film forming unit 300 includes a plurality of chambers 30 arranged along respective side surfaces of the vacuum transfer chamber 310 with the hexagonal column type vacuum transfer chamber 310 as the center And has a multi-chamber configuration. At least one of the plurality of chambers 30 is a film formation chamber for performing film formation on the wafer W. The number of deposition chambers is determined depending on the number of films formed on the wafer W, and is not limited to a specific number. Any of the chambers 30 may be a chamber other than the film forming process such as a cooling chamber, a heating chamber, and an etching chamber.

In this embodiment, as an example, the chamber 30 is made up of five film deposition chambers 321 to 325 and one load-lock chamber 326. The shape of the vacuum transport chamber 310 is not limited to a hexagonal columnar shape, and may be a polygonal shape corresponding to the number of the film deposition chambers 321 to 325 required, or a cylindrical shape.

The load lock chamber 326 is a thread for carrying the holder H from the standby loader 200 from the outside and for taking out the holder H that has completed the film forming process to the standby loader 200. One side of the load lock chamber 326 is connected to the vacuum conveyance chamber 310 via the vacuum gate valve 326a and the other side is connected to the standby loader 200 through the standby gate valve 326b have. By opening and closing the vacuum gate valve 326a, it is possible to switch the communication and blocking with respect to the vacuum transport chamber 310. By opening and closing the standby gate valve 326b, the communication with the standby loader 200 can be switched off.

In the inside of the load lock chamber 326, a holding portion (not shown) for holding the loaded wafer W is provided. Further, an unillustrated exhaust device and a pressure gauge are provided in the load lock chamber 326, so that the pressure can be reduced to a desired pressure.

The vacuum transfer chamber 310 is a chamber for loading and unloading the wafers W carried into the load lock chamber 326 into the respective deposition chambers 321 to 325. Further, an evacuating device and a pressure gauge (not shown) are provided in the vacuum transport chamber 310, so that it is possible to reduce the pressure to a desired pressure.

A transfer arm 311 is provided at the center of the vacuum transfer chamber 310 for transferring the wafer W. The transfer arm 311 extends into the load lock chamber 326 and the film deposition chambers 321 to 325 to take out the wafers W from the respective chambers and carry them into the vacuum transport chamber 310, Take it to another room.

The plurality of film formation chambers 321 to 325 open the respective vacuum gate valves 321a to 325a for loading and unloading. At the time of processing, the vacuum gate valves 321a to 325a are closed to seal the inside of the respective chambers. In each of the deposition chambers 321 to 325, film formation is performed on the wafer W. The respective film formation chambers 321 to 325 may be configured identically or differently.

Here, the structure of the film formation chamber 321 will be described as an example with reference to Figs. 9 and 10. Fig. The deposition chamber 321 has a chamber 30, a stage 31, a lifting mechanism 32, and a sputter source 33. The chamber 30 is a container which can be vacuumed inside. In the chamber 30, a pressure gauge 30a and an evacuating device (not shown) are provided. The inside of the chamber 30 is always evacuated by the evacuating device and is controlled to be in a predetermined reduced pressure state. Further, the chamber 30 is provided with a gas introducing portion 30b. The sputter gas can be introduced into the chamber 30 from the gas introducing portion 30b. As the sputter gas, for example, an inert gas such as argon may be used.

The stage 31 is a member provided in the vicinity of the inner bottom of the chamber 30 and in which the holder H accommodating the wafer W is disposed. The stage 31 has a disk shape and is connected to and supported by a shaft 31a extending from the bottom surface of the chamber 30. [ The shaft 31a hermetically penetrates the bottom surface of the chamber 30 and communicates with the outside.

The stage 31 has a convex shape in cross section due to the projection of the central portion. The upper surface of the central portion enters from the opening H0 of the holder H, and becomes a flat arrangement surface on which the wafer W is arranged. This arrangement surface constitutes an electrostatic chuck 31b. The electrostatic chuck 31b is composed of a metal base member and a ceramic dielectric member. The placement surface of the wafer W is the upper surface of the dielectric.

An electrode is provided inside the dielectric, and when a voltage is applied to the electrode, an electrostatic force is generated between the placement surface and the wafer W disposed thereon, and the wafer W is adsorbed and fixed on the upper surface of the dielectric. A cable is connected to a power supply (not shown) provided outside the chamber 30 through the inside of the shaft 31a of the stage 31 to supply electric power to the electrode inside the dielectric. A cooling mechanism (not shown) is provided on the stage 31 so as to cool the stage 31 by a cooling mechanism.

The lifting mechanism (32) is provided near the bottom of the chamber (30). The lifting mechanism 32 has a rod 32a, a table 32b, and a pin 32c. The rod 32a hermetically penetrates the bottom of the chamber 30 and is connected to a driving mechanism (not shown) such as a cylinder device or a motor, outside the chamber 30. [ By driving the driving mechanism, the rod 32a ascends and descends inside the chamber 30. [

The table 32b is attached to the upper end of the rod 32a. The table 32b is, for example, in the form of a disk and is arranged substantially parallel to the stage 31 on the lower side of the stage 31. [ A through hole is formed at the center of the table 32b. The shaft 31a of the stage 31 penetrates the through hole. The table 32b is moved up and down relative to the stage 31 and the shaft 31a by the lifting and lowering of the rod 32a.

A plurality of pins 32c are vertically installed on the upper surface of the table 32b. In the stage 31, a guide hole penetrating in the vertical direction of the chamber 30 is formed corresponding to the number of the pins 32c, though not shown. Each of the pins 32c is inserted through these guide holes and moves up and down in accordance with the upward and downward movement of the table 32b.

As shown in Fig. 9, the pins 32c are lifted to thereby receive and hold the holder H carried in from the vacuum transport chamber 310 by the transport arm 311. As shown in Fig. 10, The wafer W placed on the holder H is transferred to the electrostatic chuck 31b which is the upper surface of the stage 31. [ Therefore, the pin 32c is set to rise from the carrying arm 311 to the receiving position at which the holder H is received. The upper end of the pin 32c is set to be lowered at least to the same position as the upper surface of the guide hole of the stage 31. [ The upper surface of the stage 31 is a film formation position where film formation is performed on the wafer W.

The sputter source 33 is a supply source of a film forming material that is deposited on the wafer W and becomes a film. The sputter source 33 is disposed at an upper portion of the chamber 30. [ The sputter source 33 is composed of a target 33a, a backing plate 33b, and a conductive member 33c.

The target 33a is attached, for example, to the upper surface of the chamber 30, and the surface of the target 33a is disposed so as to face the stage 31 provided in the vicinity of the bottom of the chamber 30. [ The target 33a is made of a film forming material, and any well-known film forming material can be used. For example, titanium, silicon, or the like can be used. The shape of the target 33a is, for example, a columnar shape. However, other shapes such as an elliptical columnar shape and a prismatic shape may be used.

The backing plate 33b is a member that holds the surface of the target 33a opposite to the stage 31. [ The conductive member 33c is a member for applying electric power from the outside of the chamber 30 to the target 33a through the backing plate 33b. The sputtering source 33 is provided with a magnet, a cooling mechanism, and the like as required.

A power source 34 is connected to the sputter source 33. The power source 34 plasmatizes the sputter gas introduced around the target 33a by applying electric power to the target 33a. The power source 34 in the present embodiment is, for example, a DC power source for applying a high voltage. In the case of a device for performing high-frequency sputtering, an RF power source may be used.

A sputter gas is introduced into the chamber 30 and a DC voltage is applied from the power source 34 to the target 33a. By the application of the DC voltage, the sputter gas is converted into plasma, and ions are generated. When the generated ions collide with the target 33a, the material of the target 33a protrudes as particles. The protruding particles are deposited on the wafer W placed on the stage 31, so that a thin film is formed on the wafer W.

The control device 400 is a device for controlling each part of the standby loader 200 and the film forming part 300 described above. The control device 400 can be constituted by, for example, a dedicated electronic circuit or a computer operated by a predetermined program. The control device 400 is programmed with control contents of each part and is executed by a processing device such as a PLC or a CPU. Accordingly, it is possible to cope with various film forming specifications.

The configuration of the control device 400 will be described with reference to Fig. 11 which is a virtual functional block diagram. That is, the control device 400 includes a mechanism control section 40, a display processing section 41, a first setting section 42, a second setting section 43, a detection section 44, a determination section 45, (46), and an input / output control unit (47).

The mechanism control unit 40 is a processing unit for controlling the mechanisms of the respective units. The driving mechanism of the elevation shaft 233 of the conveying arm and the detection mechanism 230, the camera 21 of the image pickup unit 235, The vacuum source valve 22, the vacuum gate valves 321a to 325a and 326a and the waiting gate valve 326b, the vacuum transfer chamber 310, the film deposition chambers 321 to 325 and the load lock chamber 326, A gas supply portion 30b of the film forming chambers 321 to 325, a power source 34 and a lifting mechanism 32 of the chamber 310,

The display processing section 41 performs display processing of an image picked up by the image pickup section 235. That is, as shown in Figs. 8A and 8B, the display unit 49 displays the image Sw of the reflected light captured by the imaging unit 235 on the display screen of the display unit 49. Fig. The display processing unit 41 also controls display of the first area S1, the second area S2, and the detection area D, which will be described later.

The first setting unit 42 sets a first area S1 of a predetermined size as shown in Fig. 8A. The predetermined size is, in this embodiment, the size at which the image Sw of the reflected light enters. In the present embodiment, the first area S1 is circular. The size of the reflected light image Sw is equal to or larger than the size of the image Sw of the reflected light and the wafer W is stranded in the receiving portion Hs as shown in Fig. By displacing the position, the image Sw of the reflected light actually taken may be deviated from the first area S1. The first setting unit 42 sets the position where the reflected light from the wafer W at the normal position enters each time the wafer W to be processed is replaced with a wafer W having a different material or a different pattern The first area S1 is set. The fact that the wafer W is stranded indicates that a part of the outer periphery of the wafer W comes into contact with the side surface of the accommodating portion Hs or the upper surface of the holder H, For example, states such as (B), (D), (E), and (F) The state of stranded in the receptacle Hs indicates a state as shown in (B) and (D).

In addition, depending on the state of warping of the wafer W, there is a possibility that the offset amount of the position of the image Sw of the reflected light caused by the reflection of light may become large. Therefore, It is preferable to set it slightly larger than the wafer W.

The second setting unit 43 sets a second area S2 that is larger than the first area S1 and into which the first area S1 is entirely set. In the present embodiment, the second region S2 is a concentric circle having a larger diameter than the first region S1. 12, assuming that the diameter of the image Sw of the reflected light is?, The diameter of the first region S1 is?, And the diameter of the second region S2 is?,? do.

The detection unit 44 detects a value corresponding to the area of the area where the image of the reflected light Sw overlaps with the area between the first area S1 and the second area S2. The region thus detected is referred to as a detection region (D). That is, the detecting unit 44 extracts an area of a light amount equal to or larger than a preset threshold value as an image Sw of reflected light, and extracts the image of the extracted reflected light Sw from the first area S1 and the second area S2 As a detection area D. [0041] As shown in Fig. The value corresponding to the area of the detection area D can be obtained by adding the number of pixels in the part overlapping with the area between the first area S1 and the second area S2, for example. The value corresponding to the area is a value that increases or decreases in proportion to the area, and may be a value of the number of pixels itself or a value of an area calculated based on the number of pixels. The area value may be an area value on the screen or a real area value calculated based on the number of pixels and the scale of the imaging area.

The determining section 45 determines whether or not the position of the wafer W relative to the holder H is abnormal based on whether or not the value detected by the detecting section 44 exceeds a threshold value. The area of the detection region D differs depending on the amount of landing of the wafer W. [ Variation in the area of the detection area D occurs when a shift occurs due to the kind of the wafer W, for example, the difference in surface property. Therefore, the threshold value for discriminating whether the detection region D is normal or abnormal is different from the area of the detection region D.

For example, as shown in Fig. 13, (A) to (D) show a case in which the wafer W is not pushed out of the accommodating portion Hs, The wafer W is pushed out. (A), (B) and (E) show a case where the wafer W has convex curls downward, and (C), (D) . In the present embodiment, it is permitted to be OK, that is, normal, in the case of (A) to (D), NG in the case of (E), (F)

There is a possibility that the wafer W can not be sucked by the electrostatic chuck 31b when the wafer W is transported to the stage 31 in the states (E) and (F) of Fig. The portion of the wafer W not in contact with the stage 31 is not sufficiently cooled from the stage 31 because the wafer W is disposed in a state deviated from the normal position of the stage 31 even if it is adsorbed It is heated up. In addition, there is a possibility that a film to be formed adheres to the upper surface of the stage 31 on which the wafer W is not disposed.

14, the area of the detection area D varies depending on the type of the wafer W even if the grounding amount p of the wafer W is the same. This is because the reflectance or the like of light differs depending on the surface property of the wafer W, and thus the outline is sharp or faint, and the size of the image Sw of the reflected light to be imaged is not constant. For example, FIG. 15 shows the relationship between the landing amount of the wafer W and the value detected by the detecting unit 44. In FIG. The circular, square, and triangular markers in Fig. 15 represent wafers W having different surface properties.

For each wafer W, a detection value that is a value detected by the detection unit 44 is obtained as follows. The wafer W is placed on the holder H in a predetermined amount of landing and set on the support 231 of the detection mechanism 230. [ Then, the holder H is rotated 360 degrees by 30 degrees, and 12 images of the reflected light image Sw are captured. A detection value that is a value corresponding to the area of the detection area D is obtained from the image Sw of the each reflected reflected light.

The detected values of the wafers W indicate the upper limit values of the detected values of the wafers W by the respective markers in the stranding amounts a and b. In the stranding amount c, the lower limit value of the detection value of each wafer W is indicated by each marker. The distribution of the detection values in the same wafer W is represented by an error. In FIG. 15, the distribution of all detected values in a certain amount of stranding is indicated by an error bar because the error bars of the wafers W are overlapped. These error bars are referred to as error bars EB1, EB2, and EB3.

The detection values of the wafers W indicated by the markers are different from each other when the ground weights a, b, and c are compared with each other. This is presumably because the surface properties are different. In addition, there is variation in the detection value of the same wafer W as well. This is presumably because the wafer W is warped.

For example, in the case of the stranding amount c or more (or more), when it is judged that it is pushed out of the holder H, that is, it is judged to be abnormal, a value larger than the upper limit value , And a value smaller than the lower limit value (square value) of the detection values of the error bar EB3 is set as the threshold value Th1.

If a value larger than the upper limit value of the error bar EB2 is set as the threshold value Th1, processing is performed as if the wafer W is contained in the accommodating portion Hs when the detected value is Th1 or less. Accordingly, it is possible to prevent a decrease in productivity due to frequent stopping processing, even though it is not pushed out of the holder H, and is judged to be abnormal. When the threshold value Th1 is set as a value smaller than the lower limit value among the detection values of the error bar EB3, the possibility that the wafer W pushed out of the holder H is carried into the deposition unit 300 is reduced The safety can be secured. This is suitable when the difference between the upper limit value of the error bar EB2 and the lower limit value of the error bar EB3 is large.

When the difference between the upper limit value of the error bar EB2 and the lower limit value of the error bar EB3 is small, a value within a range of the error bar EB2, for example, a square marker value may be set as the threshold value Th2. In this case, even though the holder H does not come out of the holder H, it is judged to be abnormal and the stopping process occurs, but the safety is ensured.

The storage unit 46 is a configuration unit that stores information necessary for the control of the present embodiment. This information includes the timing of imaging the camera 21 of the image pickup section 235, the light quantity of the light source 22, the setting conditions of the first area S1 set by the first setting section 42, A setting condition of the second area S2 set by the setting section 43, a detection value by the detection section 44, a threshold value of the determination by the determination section 45, and a determination result. The setting condition of the second area S2 includes a difference value between the diameter of the first area S1 and the diameter of the second area S2. Based on the information stored in the storage unit 46, the mechanism control unit 40 generates and outputs control signals for the respective units.

The storage unit 46 can be constituted by, for example, various memories, hard disks, and the like. A storage medium used as a temporary storage area is also included in the storage unit 46. [ VRAM for image display and the like can also be recognized as the storage unit 46. [ The input / output control unit 47 is an interface for controlling conversion and input / output of signals between the respective units to be controlled.

An input unit 48 and a display unit 49 are connected to the control device 400. [ The input unit 48 is an input device such as a switch, a touch panel, a keyboard, and a mouse for an operator to operate the deposition apparatus 100 through the control apparatus 400. [ An instruction to set the first region S1 by the first setting section 42, a difference value between the diameter of the second region S2 and the diameter of the first region S1, The threshold value and the like can be input from the input unit 48. The second setting unit 43 sets the second area S2 on the basis of an instruction to set the first area S1 from the input unit 48 and a setting condition of the second area S2.

The display unit 49 is an output device such as a display, a lamp, and a meter for making information for confirming the state of the apparatus visible to an operator. The display displays information indicating the area of the detection area D on the display screen. The information indicating the area of the detection area D may be an image representing the detection area D, a numerical value of the area of the detection area D, or both.

For example, as shown in Fig. 8A, when the operator designates an arbitrary point outside the image Sw of the normal reflected light on the display screen by the input unit 48, the first setting unit 42 sets, The first area S1 is set such that the image Sw of the reflected light enters the locus passing through the designated point. Further, the second setting unit 43 sets, as the second area S2, a concentric circle having a diameter larger by the length set in the setting condition with respect to the diameter of the first area S1.

Thus, the display of the display unit 49 displays the image of the reflected light Sw, the first area S1, and the second area S2 on the display screen. As shown in Fig. 8B, the detection area D is an area overlapping the area between the first area S1 and the second area S2 in the image Sw of the reflected light. The display also displays the determination result of the determination section 45. [ For example, when it is determined as abnormal, the detection area D is distinguished from other areas by color distinguishing display. It is also possible to provide an output device for notifying of the abnormality by voice.

[action]

Next, the operation of the deposition apparatus 100 according to the present embodiment will be described. A detection method for detecting an abnormality in the position of the wafer W by the following procedure is also an aspect of the present invention. That is, the holder H taken out from the holder supply portion 210 by the carrier arm is disposed on the support 231 of the detection mechanism 230, as shown in Fig. On the other hand, the wafer W taken out of the wafer supply unit 220 by the transfer arm is transferred to the upper side of the holder H arranged on the support table 231.

The lifting plate 232 is lifted to receive the wafer W from the carrier arm as shown in Fig. The lifting plate 232 is lowered and the wafer W is placed in the housing portion Hs of the holder H. [ The processing for detecting the deviation of the wafer W placed on the holder H in this manner will be described with reference to the flowchart of FIG. 16 in addition to the above-described drawings.

(Area setting processing)

Processing for setting the first area S1 and the second area S2 will be described. First, light from a light source 22 is irradiated onto a wafer W at a normal position with respect to the holder H, and the reflected light is picked up by the camera 21 (step 101). The image of the picked-up wafer W is displayed on the display screen of the display as shown in Figs. 8A and 8B (step 102).

The operator looks at the image of the wafer W displayed on the display and specifies the outside of the outline of the wafer W (step 103). Then, the first setting unit 42 sets a circle in which the image of the wafer W enters beyond the designated point as the first area S1 (step 104). The second setting unit 43 sets the concentric circle in which the first area S1 enters as the second area S2 (step 105). The set first area S1 and the set second area S2 are displayed on the display.

(Detection processing)

Next, processing for detecting an abnormality in the position of the wafer W based on the set first region S1 and the second region S2 will be described. As described above, the light source 22 irradiates light onto the wafer W housed in the housing Hs of the holder H, and the reflected light is picked up by the camera 21 (step 106).

The image Sw of the reflected light of the picked-up wafer W is superimposed on the first area S1 and the second area S2 and displayed on the display (step 107). The detecting unit 44 detects a value corresponding to the area of the area where the image of the reflected light captured by the camera 21 overlaps with the area between the first area S1 and the second area S2 (Step 108).

The judging unit 45 judges whether or not the detected value exceeds the threshold value (step 109). The threshold value is determined by preparing the graph shown in FIG. 15 from the experiment of the dictionary. When the threshold value is exceeded (YES in step 109), it is judged that the amount of deviation is large and the amount of pushed out from the accommodating section Hs is large (step 110). If it is judged to be abnormal, the display displays information indicating an abnormality (step 111), and the standby loader 200 and the film forming section 300 stop the operation (step 112).

In this case, the operator corrects the position of the wafer W on the holder H, and then starts the operation of the standby loader 200 and the film forming unit 300. Alternatively, the wafer W on the holder H is taken out. If the threshold value is not exceeded (NO in step 109), the detection processing is terminated. This detection processing is performed sequentially with respect to the holder H disposed in the detection mechanism 230.

(Film forming process)

Next, the film forming process for the wafer W whose position has been corrected or the wafer W at the normal position as described above will be described. The standby gate valve 326b is opened and the holder H in which the wafer W is placed is carried into the load lock chamber 326 by the transfer arm.

At this time, the load lock chamber 326 is under atmospheric pressure, and the vacuum gate valve 321a on the vacuum transfer chamber 310 side is closed. When the transfer arm carrying the wafer W retracts from the load lock chamber 326, the standby gate valve 326b is closed. Subsequently, the load lock chamber 326 is evacuated to reduce the pressure to a predetermined pressure. When the pressure reduction is completed, the vacuum gate valve 321a of the load lock chamber 326 is opened and communicated with the vacuum transfer chamber 310. In addition, the vacuum transport chamber 310 is previously decompressed.

The transfer arm 311 of the vacuum transfer chamber 310 enters the load lock chamber 326. The carrying arm 311 holds the holder H and brings it into the vacuum transport chamber 310. When the transfer is completed, the vacuum gate valve 321a connecting the load lock chamber 326 and the vacuum transfer chamber 310 is closed.

Next, the vacuum gate valve 321a of the deposition chamber 321 adjacent to the load lock chamber 326 is opened, and the transfer arm 311 holding the holder H enters the chamber 30. As shown in Fig. 9, the lifting mechanism 32 of the film deposition chamber 321 raises the plurality of pins 32c to the receiving position in accordance with the arrival timing of the carrier arm 311. [

The carrying arm 311 places the holder H holding it on the upper end of the pin 32c. The transfer arm 311 is retracted from the film formation chamber 321 and the vacuum gate valve 321a connecting the vacuum transport chamber 310 and the film formation chamber 321 is closed.

When the vacuum gate valve 321a is closed, the lifting mechanism 32 is operated to lower the pin 32c to the stage 31. [ Thus, the holder H is disposed on the stage 31. [ 10, the placing surface of the stage 31 enters from the opening H0 of the holder H, and contacts the wafer W. As shown in Fig. Since static electricity is applied to the electrostatic chuck 31b on the placement surface by energization, the wafer W is attracted and fixed on the upper surface of the electrostatic chuck 31b.

When the inside of the chamber 30 is depressurized to a predetermined pressure, the sputter gas is introduced into the film formation chamber 321 from the gas introduction portion 30b. A direct current voltage is applied from the power source 34 to the target 33a to plasmaize the sputter gas. The ions generated from the plasma collide with the target 33a and the particles of the film forming material of the collided target 33a protrude and are deposited on the wafer W disposed on the stage 31. [ As a result, a thin film is formed on the wafer W.

When the film formation is completed, the voltage application to the electrodes inside the electrostatic chuck 31b is stopped, and the chucking of the wafer W by the electrostatic chuck 31b is released. The lifting mechanism 32 lifts the pin 32c and lifts the wafer W from the stage 31. Then, The pin 32c is raised to the receiving position. The vacuum gate valve 321a of the film deposition chamber 321 is opened and the transfer arm 311 of the vacuum transfer chamber 310 is introduced into the chamber 30.

The wafer W is held by the transfer arm 311 and is taken out of the chamber 30. When the wafer W is taken out, the vacuum gate valve 321a of the film formation chamber 321 is closed. Subsequently, the vacuum gate valve 322a of the deposition chamber 322 adjacent to the deposition chamber 321 is opened and the wafer W is carried into the chamber 30. In this manner, the wafer W is carried into the plurality of film deposition chambers 321 to 325 sequentially to perform necessary film formation processing.

[effect]

(1) As described above, the film forming apparatus 100 of the present embodiment includes a first setting section 42 for setting a first region S1 of a predetermined size, A second setting section 43 for setting a second area S2 in which the first area S1 is entirely placed and a second setting section 43 for setting the image of the reflected light of the wafer W, A detection unit 44 for detecting a value corresponding to an area of an area overlapping with an area between the first area S2 and the second area S2 based on whether or not the value detected by the detection unit 44 exceeds a threshold value And a determining section 45 for determining whether or not the position of the wafer W with respect to the holder H is abnormal.

Thus, by using the image Sw of the reflected light of the picked-up wafer W, the abnormality of the position of the wafer W having different surface properties can be detected by using the common detection means. The detection area D, which is an area overlapping the area between the first area S1 and the second area S2, varies in area depending on the amount of stranding of the wafer W, It is possible to accurately determine an abnormality of the position even if the wafer W has warp or warp.

(2) The first area S1 is a size into which the image Sw of the reflected light from the wafer W in the normal position accommodated in the holder H enters. Therefore, it is easy to determine the degree of stranding according to the amount pushed out from the first area S1.

(3) The first area S1 and the second area S2 are concentric circles. Since the distance between the concentric circles is uniform in the 360 占 direction, it is possible to determine whether the wafer W is stranded in any direction in the holder H by judging the abnormality by the overlapping area between the concentric circles.

(4) An input section 48 for instructing the setting of the first area S1 by the first setting section 42 and the second setting section 43 has an input section 48 for setting the first area S1 by the input section 48, The second area S2 is set. When the first area S1 is set according to the instruction of the input unit 48, the second area S2 is also set. Therefore, when the wafers W of different sizes are processed, 2 area S2 can be easily changed.

(5) The display section 49 displays information corresponding to the area where the image Sw of the reflected light overlaps with the area between the first area S1 and the second area S2. Therefore, the operator can visually recognize the degree of stranding of the wafer W. [

(6) The display unit 49 displays information indicating the above. Therefore, the operator can visually recognize the abnormality of the position of the wafer W, and can cope early.

(7) A single light source 22 for irradiating the wafer W with light, and a camera 21 for imaging the reflected light from the wafer W. Thus, halation by the plurality of light sources 22 is suppressed, and the wafer W can capture an accurate image. Therefore, it is possible to accurately determine an abnormality in the position of the wafer W with a simple structure.

[Other Embodiments]

(1) The present invention is not limited to the above-described embodiment, and the constituent elements can be suitably modified within a range not departing from the gist of the present invention. Furthermore, a plurality of components disclosed in the above-described embodiments may be appropriately combined. For example, some of the constituent elements may be deleted from the constituent elements described in the above embodiments, and the constituent elements extending over different embodiments may be appropriately combined.

(2) The size of the accommodating portion Hs of the holder H should be such that the wafer W can be accommodated. However, when the holder H is lifted from the stage 31 to the pins 32c after the film formation, the wafer W may be splashed. This is considered to be caused, for example, by the fact that the electrostatic chuck 31b remains in the electrostatic force. At this time, if the depth of the accommodating portion Hs is shallow, the depth dp (see Fig. 14) is required to some extent in the accommodating portion Hs because it may be stranded as it is pushed out from the holder H. On the other hand, when the depth dp of the accommodating portion Hs is increased, the film forming material protruding from the target at the time of film formation is shielded by the holder H so that the film thickness of the outer periphery of the wafer W becomes larger It becomes thinner. As a result of intensive studies, the inventor has found that it is preferable that 1.8 mm ≤ dp ≤ As a result, it is possible to prevent the uniformity of the film formation and the stranding that is pushed out after the film formation.

(3) The work to be film-formed is not limited to the semiconductor wafer W but can be applied to various work such as optical disks such as DVD and hard disks, mirrors, display panels, and solar panels. The shape of the work is not limited to a circular shape, and may be a polygonal shape such as a quadrangle, or a solid body. For example, it may be a complex including a curved surface including a single or plural curved surfaces such as a polyhedral, a hemisphere, a dome, a bowl, and the like and a curved surface such as a cylinder, a cone, or a cone and a plane made up of a plurality of planes such as a cube and a rectangular parallelepiped. Further, a protective adhesive tape may be adhered to a surface opposite to the surface on which the wafer W is to be formed, that is, a surface on which the circuit is formed, before film formation.

(4) The first area S1 and the second area S2 are not limited to a circle. A polygon may be used to match the shape of the work. In addition, the size of the first area S1 is not necessarily larger than the work, and may be smaller than the work. The shape of the holder H may be a shape adapted to the shape of these workpieces. The holder H may be a member that arranges and transports a work, and may be a title such as a tray, a susceptor, or the like.

(5) The reflected light from the work may be external light or natural light. That is, any light source may be used to obtain reflected light from the work. Further, the light source may be an embodiment in which light is guided by the optical fiber to irradiate the work.

(6) The specific configuration of the film forming unit 300 is not limited to the above-described embodiment. It may be an in-line type film forming apparatus. A heater may be provided on the stage 31 to perform preliminary heating. The mechanism for holding the holder H may be a mechanical chuck mechanism. Further, a dedicated chamber 30 for performing preliminary heating may be provided. For example, a pre-treatment chamber may be provided between the load lock chamber 326 and the film formation chamber 321, and pre-heating may be performed in the pre-treatment chamber. Further, the pre-treatment in the pretreatment chamber may be used in the load lock chamber 326 as well.

100: Film forming apparatus 200: Standby loader
210: holder supply part 220: wafer supply part
230: Detection mechanism 231:
232: lifting plate 233: lifting shaft
234: column 235:
21: camera 22: light source
300: Film forming part 310: Vacuum conveying room
311: Transfer arm 321 to 325:
321a to 325a: vacuum gate valve 326: load lock chamber
326a: Vacuum gate valve 326b: Waiting gate valve
30: chamber 30a: pressure gauge
30b: gas introduction part 31: stage
31a: shaft 31b: electrostatic chuck
32: lifting mechanism 32a: rod
32b: table 32c: pin
33: sputter circle 33a: target
33b: backing plate 33c: conductive member
34: Power source 400: Control device
40: instrument control section 41: display processing section
42: first setting unit 43: second setting unit
44: detecting section 45:
46: storage unit 47: input / output control unit
48: input unit 49:

Claims (9)

A first setting unit for setting a first area of a predetermined size,
A second setting unit that sets a second area that is larger than the first area and into which the first area is entirely set,
A detector for detecting a value corresponding to an area of an area of the reflected light from the picked up work accommodated in the holder and overlapping an area between the first area and the second area;
Based on whether or not the value detected by the detecting section exceeds a threshold value,
And a detection unit for detecting the workpiece. 2. The workpiece detection apparatus according to claim 1, wherein the first area is a size into which an image of reflected light from a work at a normal position accommodated in the holder enters. The work detection device according to claim 1 or 2, wherein the first region and the second region are concentric circles. 3. The apparatus according to claim 1 or 2, further comprising an input unit for instructing setting of the first area by the first setting unit,
And the second setting unit sets the second area in accordance with the setting of the first area by the input unit. The workpiece detection device according to claim 1 or 2, further comprising a display unit for displaying information corresponding to the area. The work detection device according to claim 5, wherein the display unit displays information indicating the abnormality. 3. The work machine according to claim 1 or 2, further comprising: a single light source for irradiating the work with light;
An image pickup section for picking up reflected light from the work;
And a detection unit for detecting the workpiece. A workpiece detecting apparatus according to claim 1 or 2,
A film forming section for performing film forming on a workpiece whose position is determined to be abnormal by the workpiece detecting device
The film forming apparatus comprising: A computer or electronic circuit,
A first setting process of setting a first area of a predetermined size,
A second setting process for setting a second area that is larger than the first area and into which the first area is entirely set,
A detection process of detecting a value corresponding to an area where the image of the reflected light from the work overlaps with the area between the first area and the second area;
Based on whether or not the value detected by the detection processing exceeds a threshold value, a determination process for determining whether or not the position of the work with respect to the holder is abnormal
Is executed.

Images