JPH0716351U - Workpiece holding device - Google Patents

Abstract

(57) [Summary] [Structure] Inside the platen 1 that holds the object to be processed,
A refrigerant circulation region 2 is provided, and this refrigerant circulation region 2
Are provided with arcuate partition walls 5, 6 and 7 having different diameters and concentric shapes to form concentric refrigerant passages. A coolant introduction port 3 is provided at a substantially central portion of the coolant circulation region 2, and a coolant discharge port 4 is provided at an upper end portion thereof. Each partition wall 5, 6, 7 has an air vent hole 5b, 6b, 7b at a portion that divides the length of the arc into two substantially equal parts.
Are formed. [Effect] The refrigerant flows substantially uniformly in the refrigerant circulation region 2. Further, air does not remain in the refrigerant passages 8 to 11, and the refrigerant flows all over the refrigerant circulation region 2. As a result, the object to be processed that is held in close contact with the platen 1 is cooled substantially evenly over the entire area thereof, and the situation in which the surface temperature of the object to be processed becomes uneven is avoided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an object-holding device that is provided in, for example, an ion implantation apparatus and holds an object to be processed such as a semiconductor wafer, and more specifically, it has a function of uniformly cooling the object to be processed over its entire area. The present invention relates to a processed product holding device.

[0002]

[Prior art]

 The ion implanter ionizes the impurities to be implanted, selectively extracts these impurity ions by mass spectrometry using a magnetic field, accelerates them with an electric field, and irradiates the object to be treated such as a silicon wafer. Impurities are injected into the object. Since this ion implanter can implant impurities, which determine the characteristics of the device in the semiconductor process, to an arbitrary amount and depth with good controllability, it is an important device for manufacturing integrated circuits at present.

In the above ion implantation apparatus, the object to be processed is irradiated with an ion beam while being held by a platen provided in a high vacuum target chamber. In this case, the object to be treated receives the energy of the beam, and its temperature rises with the irradiation time of the beam. In order to implant impurity ions into an arbitrary amount and depth with good controllability and obtain a desired implantation result, it is necessary to prevent overheating of the object to be processed during beam irradiation.

Therefore, conventionally, in order to avoid an extreme temperature rise of the object to be processed during beam irradiation, as shown in FIG. 3 and FIG. 4, a strip-shaped platen 51 is provided inside the disk-shaped platen 51 for fixing and holding the object to be processed. The cooling medium channel 56 is formed, and a cooling medium such as water is flown through the cooling medium channel 56 to cool the object to be processed.

Note that FIG. 3 is a sectional view taken along the line BB of FIG. Further, a portion above the line X in FIG. 4 shows a cross section taken along the line CC of FIG. 3, and a portion lower than the line X shows a cross section taken along the line DD of FIG. There is. Further, the arrow Q 1 shown in FIGS. 3 and 4 shows the flow of the refrigerant.

In order to perform uniform ion implantation, the platen 51 is driven by a platen rotation drive unit 52 to rotate as shown in FIG. The platen rotation drive unit 52 is supported by a platen arm 53. Inside the platen rotation drive unit 52 and the platen arm 53, a refrigerant introduction pipe 54 and a refrigerant discharge pipe 55 communicating with a pump (not shown) are provided. Has been. The refrigerant introducing pipe 54 is connected to a refrigerant introducing port 57 provided near the center of the platen 51, and the refrigerant discharging pipe 55 is connected to a refrigerant discharging port 58 provided near the refrigerant introducing port 57. Has been done.

In the above structure, when the ion implantation is performed, the object to be processed is first held so that the back surface is in close contact with the holding surface 51 a of the platen 51. Since the ion beam travels in a substantially horizontal direction, the platen arm 53 moves so that the object to be processed is in an upright state and performs a pendulum motion about the axis b (the platen arm 53 rotates about the axis b). Then swing up and down). In synchronization with this, since the platen 51 is rotationally driven by the platen rotation drive unit 52 in the direction opposite to the rotation direction of the platen arm 53 and at the same angular velocity, the orientation of the platen 51 is always kept constant. . Irradiation of the ion beam is started in this state. During the ion implantation process, the refrigerant that has passed through the refrigerant introduction pipe 54 flows into the refrigerant passage 56 from the refrigerant introduction port 57 near the central portion of the platen 51, and circulates in the refrigerant passage 56 to rotate the platen 51. After being cooled, it is discharged from the refrigerant discharge port 58 to the refrigerant discharge pipe 55. Since the platen 51 is cooled in this manner, the object to be processed whose temperature has risen is cooled by the platen 51, and overheating of the object to be processed during the ion implantation process is prevented.

[0008]

[Problems to be solved by the device]

 However, in the above-described conventional configuration, since the refrigerant discharge port 58 is located near the center of the platen 51, the refrigerant flow path 56 has a small flow rate or when air remains in the refrigerant flow path 56. Since the refrigerant does not flow to the upper end and the object to be processed cannot be cooled uniformly over the entire area, the temperature distribution of the object to be processed during the ion implantation process becomes uneven, and ion implantation cannot be performed with high accuracy. The problem arises.

The present invention has been made in view of the above, and an object of the present invention is to perform cooling substantially uniformly over the entire area of the object to be processed and to avoid uneven temperature distribution of the object to be processed. It is to provide an object holding device.

[0010]

[Means for Solving the Problems]

 An object-holding device of the present invention comprises a holding member that holds an object to be processed in close contact with a holding surface, and a hollow refrigerant circulation region through which a refrigerant flows is formed inside the holding member. In order to solve the above-mentioned problems, the following means are taken.

That is, a coolant introduction port for introducing a coolant into the coolant distribution region is provided at a substantially central portion of the coolant distribution region, and a coolant from the coolant distribution region is provided at an upper end of the coolant distribution region. A refrigerant discharge port for discharging is provided, and a plurality of arc-shaped partition walls having a refrigerant circulation opening are provided in the refrigerant circulation region in a concentric manner with different diameters centered on the refrigerant introduction port to form a refrigerant channel. In each of the arc-shaped partition walls, an air vent hole is formed at a site that divides the arc length into two substantially equal parts, and the refrigerant circulation opening and the air vent hole of the adjacent arc-shaped partition walls are arranged to face each other. In addition, the air vent hole of the arcuate partition wall having the largest diameter and the refrigerant discharge port are arranged to face each other.

[0012]

[Action]

 According to the above configuration, the refrigerant flow region is provided inside the holding member that holds the object to be processed, and the plurality of arc-shaped partition walls having different diameters and concentricity are provided in the refrigerant flow region. , Concentric refrigerant channels are formed. Further, a refrigerant introduction port is provided at a substantially central portion of the refrigerant circulation region, and a refrigerant discharge port is provided at an upper end portion of the refrigerant circulation region. For this reason, the refrigerant is introduced from the substantially central portion of the refrigerant circulation region, flows through the concentric refrigerant channels in the refrigerant circulation region, and is discharged from the upper end portion of the refrigerant circulation region.

Here, in each of the arcuate partition walls, an air vent hole is formed at a site that divides the length of the arc into two substantially equal parts. That is, the air vent hole is formed on the opposite side of the center of the arc from the refrigerant flow opening. Then, the refrigerant circulation openings and the air vent holes of the adjacent arcuate partition walls are arranged to face each other. That is, the refrigerant distribution openings of the adjacent partition walls are arranged so that the opening directions thereof are different by about 180 °. The air vent hole of the arcuate partition wall having the largest diameter and the refrigerant discharge port are arranged to face each other. That is, at the upper end portion of each arcuate partition wall, there is either a refrigerant circulation opening or an air vent hole.

Therefore, when the refrigerant flows through the refrigerant passage, the air remaining at the upper end of each arcuate partition wall passes through the refrigerant circulation opening or the air vent hole and moves to the upper end of the refrigerant circulation region. Further, since the refrigerant discharge port is provided at the upper end of the refrigerant flow region, all the air in the cooling medium flow region is discharged from the refrigerant discharge port and does not remain in the refrigerant flow region. Therefore, the refrigerant flows all over the refrigerant circulation region.

Further, since the refrigerant flows through the refrigerant passages formed concentrically, the refrigerant flows substantially uniformly in the refrigerant circulation region. That is, in the case of an angled refrigerant flow path, the flow at the corners is stagnant and does not become a uniform flow, but when the refrigerant flow paths are formed in concentric circles as described above, the flow is There is no delay, and the flow of the refrigerant becomes substantially uniform.

As described above, since the refrigerant flows substantially uniformly throughout the refrigerant circulation region, the holding member is cooled substantially uniformly over the entire area, and as a result, the holding member adheres to the holding surface of the holding member. The object to be held is cooled substantially uniformly over the entire area.

[0017]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

The object-holding device according to the present embodiment is provided in an ion implantation apparatus, and as shown in FIGS. 1 and 2, serves as a holding member for holding an object to be processed such as a semiconductor wafer. The disk-shaped platen 1 is provided. In this embodiment, a so-called hybrid scan type ion implanter is used, in which the ion beam is electrostatically scanned in the horizontal direction and the platen 1 holding the object to be processed is mechanically scanned in the vertical direction. However, the present invention is not limited to this.

Inside the platen 1, a hollow refrigerant flow region 2 through which a refrigerant flows is formed in a substantially circular cross section. A coolant inlet port 3 for introducing a coolant into the coolant distribution region 2 is provided at the center of the coolant distribution region 2, and the coolant distribution region 2 is provided at the upper end of the coolant distribution region 2. A refrigerant outlet 4 for discharging the refrigerant from 2 is provided.

Further, in the refrigerant circulation region 2, as shown in FIG. 1, arcuate partition walls 5, 6 and 7 respectively having refrigerant circulation openings 5 a, 6 a and 7 a are formed around the refrigerant introduction port 3. Are provided concentrically with different diameters.

In addition, in each of the arc-shaped partition walls 5, 6, and 7 described above, a portion that divides the length of the arc into substantially equal parts is formed, that is, the center of the arc is separated from the refrigerant circulation openings 5a, 6a, and 7a. Air vent holes 5b, 6b, and 7b are formed on the opposite sides, respectively. The air vent holes 5b, 6b, 7b are much smaller than the refrigerant flow openings 5a, 6a, 7a, and the amount of cooling medium passing through the air vent holes 5b, 6b, 7b is very small. .

The partition walls 5, 6, and 7 are arranged such that the refrigerant circulation openings of the adjacent partition walls and the air vent holes are opposed to each other. That is, the openings of the refrigerant distribution openings of the adjacent partition walls are formed so as to differ from each other by approximately 180 °. Further, the air vent hole 7b of the partition wall 7 having the largest diameter and the refrigerant discharge port 4 are arranged to face each other.

As a result, in the refrigerant flow region 2, the arcuate partition wall 5 serves as the first coolant flow path 8, and the outer peripheral portion of the partition wall 5 and the inner periphery of the partition wall 6 serve as the second coolant flow path 9 and the partition wall 6. The outer peripheral portion and the inner peripheral portion of the partition wall 7 form a third refrigerant flow passage 10, and the outer peripheral portion of the partition wall 7 and an end portion of the refrigerant flow region 2 form a fourth refrigerant flow passage 11, respectively.

The platen 1 is rotatably supported by the platen rotation drive unit 12 shown in FIG. The platen rotation drive unit 12 is configured to rotationally drive the platen 1 holding the object to be processed during the ion implantation process in order to enable uniform ion implantation to the entire surface of the object to be processed.

The platen rotation drive unit 12 is supported by a platen arm 13 that is movably provided. Inside the platen rotation drive unit 12 and the platen arm 13, a refrigerant communicating with a pump (not shown) is provided. An introduction pipe 14 and a refrigerant discharge pipe 15 are provided. The refrigerant introduction pipe 14 is connected to the refrigerant introduction port 3 of the platen 1, and the refrigerant discharge pipe 15 is connected to the refrigerant discharge port 4 of the platen 1.

The operation of the workpiece holding device having the above-described structure will be described below.

The platen 1 of the object-holding device is provided with a clamp mechanism (not shown), and the platen 1 holds the object in close contact with the holding surface 1a shown in FIG. 2 by this clamp mechanism. .

Since the ion beam travels in a substantially horizontal direction, the platen arm 13 moves so that the object to be processed is in an upright state, and performs a pendulum motion about the axis a (the platen arm 13 about the axis a). Rotate and swing up and down). In synchronization with this, the platen 1 is rotationally driven by the platen rotation drive unit 12 in the direction opposite to the rotational direction of the platen arm 13 at the same angular velocity. As a result, the direction of the platen 1 is always kept constant so that the directions indicated by the arrows Y ₁ and Y ₂ in FIG. 1 are the vertical directions. However, the platen 1 is tilted according to the set injection angle. Then, the refrigerant is flown into the platen 1.

That is, as shown by an arrow P in FIGS. 1 and 2, the refrigerant sent from the pump passes through the platen arm 13 and the refrigerant introduction pipe 14 provided in the platen rotation drive unit 12. , Through the coolant inlet port 3 formed in the central portion of the platen 1 into the first coolant channel 8. This refrigerant flows into the second refrigerant flow path 9 through the refrigerant flow opening 5a, flows through the flow path 9, and then flows into the third refrigerant flow path 10 through the refrigerant flow opening 6a. After flowing through the passage 10, it flows into the fourth refrigerant flow passage 11 from the refrigerant flow opening 7a, flows through the flow passage 11, and then is discharged from the refrigerant discharge port 4 to the refrigerant discharge pipe 15.

At this time, the air vent holes 5 b, 6 b, 7 b are provided in the partition walls 5, 6, 7 forming the refrigerant flow paths 8 to 11, and the refrigerant discharge port 4 is provided at the upper end portion of the refrigerant flow region 2. Since it is provided, air does not remain in each of the refrigerant channels 8 to 11, and the refrigerant flows all over the refrigerant circulation region 2.

That is, air is present in the refrigerant channels 8 to 11 before flowing the refrigerant into the refrigerant channels 8 to 11, and by flowing the refrigerant into the refrigerant channels 8 to 11, most of the air is cooled. Are extruded from the refrigerant discharge port 4. Here, for example, if the partition wall 7 does not have the air vent hole 7b, there is a region in the upper end of the refrigerant channel 10 where the air remains and the refrigerant does not flow, but since the air vent hole 7b exists, the refrigerant flow The air remaining at the upper end of the passage 10 is pushed by the refrigerant pressure, escapes from the air vent hole 7b, moves to the fourth refrigerant flow passage 11, and moves to the fourth refrigerant flow passage 11 and the refrigerant discharge port 4 provided at the upper end thereof. Emitted from. In this way, since the partition walls 5, 6 and 7 are provided with the air vent holes 5b, 6b and 7b, no air remains in the respective refrigerant passages 8 to 10. Further, since the refrigerant discharge port 4 is provided at the upper end portion of the refrigerant flow region 2, all the air in the refrigerant flow region 2 is discharged from the refrigerant discharge port 4.

In this state, the platen 1 is driven by the platen rotation drive unit 2 to rotate, and the ion implantation process is started. During the ion implantation process, the temperature of the object to be processed rises due to the irradiation of the beam, the heat of the object to be processed is transferred to the platen 1, and the temperature of the platen 1 also rises. Then, as the refrigerant flows through the refrigerant passages 8 to 11 in the platen 1 as described above, the heat of the platen 1 is transferred to the refrigerant flowing in the refrigerant passages 8 to 11 in the platen 1 as described above. , The platen 1 is cooled.

Here, the refrigerant flows through the refrigerant flow paths 8 to 11 formed in a concentric shape, and therefore flows substantially uniformly in the refrigerant circulation region 2. That is, in the case of an angled coolant flow path, the flow in the corners is stagnant and does not become a uniform flow, but when the coolant flow paths 8 to 11 are formed in concentric circles as described above, any part of The flow does not become stagnant, and the flow of the refrigerant becomes almost uniform. Further, as described above, air does not remain in the refrigerant circulation region 2, and the refrigerant flows all over the refrigerant circulation region 2.

By these actions, the holding surface 1a of the platen 1 is cooled substantially uniformly over the entire area. As a result, the object to be processed that is held in close contact with the holding surface 1a is cooled substantially evenly over its entire area, the surface temperature of the object to be processed during the ion implantation process becomes substantially uniform, and ion implantation is performed with high accuracy. Done.

As described above, the apparatus for holding an object to be processed according to the present embodiment includes the platen 1 that holds the object to be processed in close contact with the holding surface 1 a, and the inside of the platen 1 has a hollow shape in which the refrigerant flows. A coolant circulation region 2 is formed, and a coolant introduction port 3 for introducing a coolant into the coolant circulation region 2 is provided at the center of the coolant circulation region 2 and the coolant circulation region 2 A coolant discharge port 4 for discharging the coolant from the coolant circulation region 2 is provided at the upper end of the arc-shaped partition wall 5 having the coolant circulation openings 5a, 6a, and 7a. 6 and 7 are provided concentrically with different diameters centered on the refrigerant introduction port 3 to form a refrigerant flow path, and each of the partition walls 5, 6, and 7 has an arc length of approximately two. Air vent holes 5b, 6b, 7b are formed in the equally divided parts, and The refrigerant flow openings and air vent holes of the adjacent partition walls are opposed to each other, and the air vent holes 7b of the arcuate partition wall 7 having the largest diameter and the refrigerant discharge port 4 are opposed to each other.

According to the above configuration, since the coolant flow paths 8 to 11 are concentrically formed in the coolant distribution region 2, the coolant flows in the coolant distribution region 2 substantially uniformly. Furthermore, since the partition walls 5, 6, and 7 forming the refrigerant passages 8 to 11 are provided with air vent holes 5b, 6b, and 7b, and the refrigerant discharge port 4 is provided at the upper end portion of the refrigerant circulation region 2. Air does not remain in each of the refrigerant flow paths 8 to 11, and the refrigerant flows in the refrigerant flow region 2 all over. As a result, the holding surface 1a of the platen 1 is cooled substantially uniformly over the entire area. Therefore, the object to be processed, which is held in close contact with the holding surface 1a, is cooled substantially evenly over its entire area, and the conventional situation in which the surface temperature of the object to be processed becomes uneven is avoided.

Although the platen 1 of the above-described embodiment is rotationally driven by the platen rotation driving unit 12, it may be fixed without rotating. Further, in the above-mentioned embodiment, the example in which the object holding device is applied to the ion implantation device is shown, but it can be applied to other devices. The above-mentioned embodiments are only for clarifying the technical contents of the present invention, and should not be construed in a narrow sense by limiting only to such specific examples. The spirit of the present invention and the utility model registration Various modifications can be made within the scope of the claims.

[0038]

[Effect of device]

 As described above, the object holding apparatus of the present invention includes the holding member that holds the object to be processed in close contact with the holding surface, and the inside of the holding member is formed with a hollow refrigerant circulation region through which the refrigerant flows. A coolant inlet port for introducing a coolant into the coolant flow region is provided substantially in the center of the coolant flow region, and the coolant flow region is provided at the upper end of the coolant flow region. A refrigerant discharge port for discharging the refrigerant is provided, and a plurality of arc-shaped partition walls having a refrigerant flow opening are provided in the above-described refrigerant flow region in a concentric manner with different diameters centered on the refrigerant introduction port. A refrigerant flow path is formed, and each of the arc-shaped partition walls has an air vent hole at a site that divides the length of the arc into two equal parts. Are facing each other and have an arc shape with the largest diameter. Ru configuration der that the vent hole and the refrigerant outlet of the walls are opposed.

Therefore, the air does not remain in the refrigerant circulation region, and the refrigerant flows all over the refrigerant circulation region. Furthermore, since the refrigerant flows through the concentrically formed refrigerant flow paths, the refrigerant flows in the refrigerant circulation region substantially uniformly. Therefore, the holding member is cooled substantially uniformly over the entire area thereof, and as a result, the object to be processed that is held in close contact with the holding surface of the holding member is cooled substantially evenly over the entire area. In addition, it is possible to avoid the situation where the temperature distribution of the object to be treated becomes uneven.

[Brief description of drawings]

1 is a schematic cross-sectional view of a platen showing an embodiment of the present invention and showing a refrigerant flow path inside the platen of an object holding apparatus.

FIG. 2 is an explanatory diagram showing a main part of the object holding apparatus.

FIG. 3 illustrates a conventional example and is a schematic cross-sectional view of a platen showing a coolant passage inside the platen of the object-to-be-treated holding device.

FIG. 4 is an explanatory diagram showing a main part of the object holding apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Platen (holding member) 1a Holding surface 2 Refrigerant distribution area 3 Refrigerant inlet 4 Refrigerant discharge port 5/6/7 Arc-shaped partition wall 5a / 6a / 7a Refrigerant distribution opening 5b / 6b / 7b Air vent hole 8 First refrigerant Flow path (refrigerant flow path) 9 Second refrigerant flow path (refrigerant flow path) 10 Third refrigerant flow path (refrigerant flow path) 11 Fourth refrigerant flow path (refrigerant flow path) 14 Refrigerant introduction pipe 15 Refrigerant discharge pipe

Claims (1)

[Scope of utility model registration request] 1. An object-to-be-processed holding apparatus comprising: a holding member for holding an object to be processed in close contact with a holding surface, wherein a hollow refrigerant flow region through which a refrigerant flows is formed in the holding member. A coolant introduction port for introducing a coolant into the coolant distribution region is provided at substantially the center of the coolant distribution region, and a coolant discharge for discharging the coolant from the coolant distribution region at the upper end of the coolant distribution region. An outlet is provided, a plurality of arcuate partition walls having a refrigerant circulation opening portion are provided in the refrigerant circulation region in a concentric manner with different diameters centered on the refrigerant introduction port to form a refrigerant passage, In each arc-shaped partition wall, an air vent hole is formed at a site that divides the length of the arc into two equal parts, and the refrigerant circulation opening and the air vent hole of the adjacent arc-shaped partition walls are arranged to face each other, and the diameter Large arc-shaped partition air vent holes and refrigerant An object-holding device, wherein the discharge port and the discharge port are arranged to face each other.