Processing apparatus

Abstract

Typically, a processing device is provided that monitors the pressure within the exhaust duct of the processing device and does not issue an alarm regarding a temporary decrease in the magnitude of the negative pressure within the exhaust duct. A machining device for machining a workpiece held by a chuck table while supplying machining fluid to the workpiece and machining unit having a spindle, the device comprises a machining chamber covering a portion of the chuck table and the machining unit, and an exhaust duct connected to the machining chamber. The exhaust duct has an exhaust path, one end of which is connected to the machining chamber and the other end of which is connected to an exhaust unit having a suction source, and a box body that communicates with the exhaust path through an opening formed on the side of the exhaust duct and includes a pressure sensor inside, wherein the opening has a size capable of reducing the impact of sudden changes in pressure of the exhaust path on the box body.

Description

Technology Field

[0001] The present invention relates to a processing apparatus for processing a workpiece while supplying processing water to a workpiece held by a chuck table. Background Technology

[0002] In the manufacturing process of semiconductor device chips, multiple intersecting lines scheduled for division are set on the surface, and a wafer having devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integrations) formed in each area partitioned by these lines is divided into multiple device chips.

[0003] When dividing a wafer into multiple device chips, for example, the back side of the wafer is first ground with a grinding device to thin the wafer to a predetermined thickness. Then, the wafer is divided into individual device chips by using a cutting device to cut the thinned wafer along each planned division line.

[0004] Processing devices, such as grinding devices and cutting devices, are provided with a processing chamber for processing wafers. The processing chamber is a closed space formed by enclosing a predetermined space with a plate or similar material. A chuck table is arranged within the processing chamber to suction and hold the wafer.

[0005] When processing a wafer while holding it on a chuck table and supplying processing water, such as pure water, the processing water containing processing debris generated during processing may diffuse into the processing room in the form of a mist.

[0006] If the mist-like processing water adheres to the windows installed in the processing unit, visibility through the windows is reduced, making it difficult to inspect the interior of the processing unit. Furthermore, if the mist-like processing water scatters out of the processing room, it contaminates the components of the processing unit located outside the room or the wafers awaiting processing.

[0007] For example, if the transport mechanism that adsorbs and transports wafers becomes contaminated by the mist-type processing water, other wafers may become contaminated through the transport mechanism, or wafers may fall and break due to poor adsorption. Furthermore, separate from the mist-type processing water containing processing debris, powder-type processing debris may diffuse into the processing chamber and contaminate it.

[0008] As such, mist-type processing water containing processing debris or powder-type processing debris all have an adverse effect on wafers or processing equipment. To avoid this harmful effect, an exhaust duct is connected to the processing room to discharge mist-type processing water or powder-type processing debris (e.g., see Patent Document 1).

[0009] The pressure inside the exhaust duct is typically set to a pressure lower than atmospheric pressure or the pressure inside the cleanroom (i.e., negative pressure). In addition, a pressure gauge may be installed in the exhaust duct to monitor whether the pressure inside the exhaust duct is appropriate.

[0010] However, the processing room is temporarily opened to the atmosphere of the atmosphere or cleanroom for the loading or unloading of wafers. Due to this temporary opening, air is introduced into the processing room and the exhaust duct, and the magnitude of the negative pressure in the exhaust duct is temporarily reduced. That is, the pressure in the exhaust duct temporarily rises to approach atmospheric pressure or the pressure in the cleanroom.

[0011] To detect abnormalities in the processing room and exhaust duct, the processing unit is configured to emit an alarm if the negative pressure within the exhaust duct drops below a predetermined threshold, even if only temporarily. When the processing unit emits an alarm, it is necessary for the operator to take countermeasures, such as deactivating the alarm.

[0012] While it is desirable to accurately detect abnormalities in the processing room and exhaust ducts, the loading and unloading of wafers are frequent operations; therefore, it is preferable for the processing device not to emit unnecessary alarms caused by these operations. If unnecessary alarms occur, operator intervention is required, which reduces productivity per unit of time. Prior art literature

[0013] [Patent Document 1] Japanese Patent Publication No. 11-188568 The problem to be solved

[0014] The present invention has been made in consideration of these problems and aims to provide a processing device that monitors the pressure within the exhaust duct of a processing device and does not issue an alarm regarding a temporary decrease in the magnitude of negative pressure within the exhaust duct. means of solving the problem

[0015] According to one aspect of the present invention, a processing device is provided for processing a workpiece held by a chuck table using a processing unit having a spindle while supplying processing water to the workpiece. The processing device comprises a processing chamber covering a portion of the chuck table and the processing unit, and an exhaust duct connected to the processing chamber. The exhaust duct has an exhaust path, one end of which is connected to the processing chamber and the other end of which is connected to an exhaust unit having a suction source, and a box body that communicates with the exhaust path through an opening formed on the side of the exhaust duct and includes a pressure sensor inside. The opening has a size capable of reducing the impact of sudden changes in pressure of the exhaust path on the box body. Effects of the invention

[0016] A processing device according to one embodiment of the present invention comprises a processing chamber and an exhaust duct connected to the processing chamber. The exhaust duct has an exhaust path and a box body. One end of the exhaust path is connected to the processing chamber, and the other end is connected to an exhaust unit having a suction source. The box body communicates with the exhaust path through an opening formed on the side of the exhaust path and includes a pressure sensor inside.

[0017] The opening connecting the exhaust path and the box body has a size capable of reducing the impact of sudden pressure changes in the exhaust path on the box body. Therefore, even if the magnitude of the negative pressure in the exhaust path temporarily decreases, the magnitude of the negative pressure inside the box body does not fall below a predetermined threshold value.

[0018] Therefore, while the pressure sensor normally monitors the pressure in the exhaust path within the exhaust duct, it is not easily affected by a temporary decrease in the magnitude of the negative pressure in the exhaust path. Accordingly, even if the magnitude of the negative pressure in the exhaust path temporarily decreases, the processing device does not emit an alarm, thereby reducing unnecessary alarms. Brief explanation of the drawing

[0019] FIG. 1 is a perspective view of a grinding device. FIG. 2 is a partial cross-sectional side view of a grinding room, etc. FIG. 3 (A) is a top view of a turntable, and FIG. 3 (B) is a perspective view of a turntable. FIG. 4 is a partial cross-sectional side view of a grinding chamber, etc. according to the present embodiment. FIG. 5 is a partial cross-sectional side view of a grinding chamber, etc. according to a comparative example. Figure 6 is a schematic diagram illustrating the pressure change in the exhaust path. Specific details for implementing the invention

[0020] With reference to the attached drawings, an embodiment according to one aspect of the present invention will be described. FIG. 1 is a perspective view of a grinding device (2) which is an example of a processing device. In addition, the X-axis direction, the Y-axis direction (front-back direction), and the Z-axis direction (vertical direction, grinding feed direction) shown in FIG. 1 are orthogonal to each other.

[0021] The grinding device (2) has a roughly rectangular base (4) that supports or accommodates components. A recess (4a) is formed in the front (one side in the Y-axis direction) of the base (4), and a conveying robot (6) that conveys a workpiece (11) (see FIG. 2, etc.) is installed in this recess (4a).

[0022] In the X-axis direction, a cassette placement area (8a) and a cassette placement area (8b) exist with a concave portion (4a) in between. For example, a cassette (10a) containing one or more workpieces (11) before processing is placed on the cassette placement area (8a).

[0023] For example, a cassette (10a) accommodates one or more workpieces (11) each having a protective tape made of resin attached to its surface. Additionally, a cassette (10b) that accommodates one or more workpieces (11) after processing is placed on the cassette placement area (8b).

[0024] At the rear (the other side in the Y-axis direction) of the cassette placement area (8a), a positioning table (12) is installed to determine the position of the workpiece (11) that has been removed by the transport robot (6). In the area adjacent to the positioning table (12) in the X-axis direction, a loading arm (14) is installed.

[0025] A disc-shaped turntable (16) rotatable in the XY plane is installed at the rear of the loading arm (14). A first rotational driving source (not shown), such as a motor for rotating the turntable (16), is arranged on the lower side of the turntable (16).

[0026] On the upper side of the turntable (16), three chuck tables (18) are installed at an angle of approximately 120 degrees in the circumferential direction of the turntable (16). One chuck table (18) is positioned in the loading / unloading area (A) closest to the loading arm (14).

[0027] In addition, a chuck table (18) is provided in each of the rough grinding area (B), which is located approximately 120 degrees clockwise from the top surface of the incoming / outgoing area (A), and the finishing grinding area (C), which is located approximately 120 degrees counterclockwise from the top surface of the incoming / outgoing area (A).

[0028] Each chuck table (18) has a disc-shaped frame body formed of ceramics or the like. A disc-shaped concave portion is formed on the upper surface of the frame body, and a disc-shaped porous plate is fixed to the concave portion in a manner that fits into the concave portion.

[0029] The lower side of the porous plate is connected to one end of a flow path (not shown) formed within the frame body. A suction source (not shown), such as a vacuum pump, is connected to the other end of this flow path. When the suction source is operated, negative pressure is generated on the upper surface of the porous plate [maintenance surface (18a) (see FIG. 2, etc.)].

[0030] A second rotary driving source (not shown), such as a motor, is installed on the underside of each chuck table (18). The output shaft of the second rotary driving source is connected to the lower part of the chuck table (18). When the second rotary driving source is operated, the chuck table (18) rotates in a predetermined direction.

[0031] At the rear of the rough grinding area (B) of the turntable (16), a rectangular support structure (22a) is installed in a manner that protrudes from the upper surface of the base (4). A grinding transfer unit (moving unit) (24) is installed on the front side of the support structure (22a).

[0032] The grinding feed unit (24) has a pair of Z-axis guide rails (26) that are approximately parallel in the Z-axis direction and fixed to the front of the support structure (22a). A Z-axis moving plate (28) is slidably attached to the pair of Z-axis guide rails (26).

[0033] A nut portion (not shown) is installed on the rear (back) side of the Z-axis moving plate (28). A Z-axis ball screw (30), installed along the Z-axis direction between a pair of Z-axis guide rails (26), is connected to the nut portion in a rotatable manner.

[0034] A Z-axis pulse motor (32) is connected to the upper part of the Z-axis ball screw (30). When the Z-axis ball screw (30) is rotated by the Z-axis pulse motor (32), the Z-axis moving plate (28) moves in the Z-axis direction along the Z-axis guide rail (26).

[0035] A rough grinding unit (processing unit) (36a) is fixed to the front of the Z-axis moving plate (28). The rough grinding unit (36a) has a cylindrical retaining member (38) fixed to the Z-axis moving plate (28). Inside the retaining member (38), a cylindrical spindle housing (40) (see FIG. 2) is installed, positioned approximately parallel to the Z-axis direction.

[0036] A portion of a cylindrical spindle (42) (see FIG. 2) arranged approximately parallel to the Z-axis direction is rotatably accommodated within the spindle housing (40). A motor (44) is connected to the upper portion of the spindle (42).

[0037] A disc-shaped wheel mount (48) is fixed to the lower part of the spindle (42). An annular grinding wheel (50a) is mounted on the lower surface of the wheel mount (48) by means of a fixing member (not shown), such as a screw.

[0038] The area immediately below the rough grinding wheel (50a) corresponds to the aforementioned rough grinding area (B). The rough grinding wheel (50a) has a toroidal wheel base (52a) formed of a metal material such as an aluminum alloy, and a plurality of rough grinding stones (54a) mounted on the lower side of the wheel base (52a) (see FIG. 2).

[0039] A plurality of rough grinding stones (54a) are arranged in an annular shape along the circumference of the lower surface of the wheel base (52a), with gaps formed between adjacent rough grinding stones (54a). The rough grinding stones (54a) are formed by mixing abrasive particles, such as diamond or cBN (cubic boron nitride), with a binder, such as metal, ceramics, or resin.

[0040] A passage (not shown) for supplying grinding water (processing water), such as pure water, to a rough grinding wheel (54a) is installed in the wheelbase (52a), wheel mount (48), spindle (42), etc. A grinding water supply unit (not shown) is connected to one end of the passage. The grinding water supply unit includes, for example, a tank in which grinding water is stored (not shown), a pump (not shown) for supplying grinding water from the tank to the wheelbase (52a), etc.

[0041] As shown in FIG. 1, a rectangular support structure (22b) is installed adjacent to one side in the X-axis direction of the support structure (22a) and also behind the finishing grinding area (C). A grinding feed unit (24) is installed in front of the support structure (22b), just like the support structure (22a).

[0042] A finishing grinding unit (processing unit) (36b) is connected to the grinding feed unit (24) of the support structure (22b). The finishing grinding unit (36b) also has a retaining member (38), a spindle housing (40), a spindle (42), a motor (44), and a wheel mount (48), just like the rough grinding unit (36a).

[0043] However, a toroidal finishing grinding wheel (50b) is mounted on the spindle (42) of the finishing grinding unit (36b) via a wheel mount (48). Immediately below the finishing grinding wheel (50b) corresponds to the aforementioned finishing grinding area (C).

[0044] The finishing grinding wheel (50b) is equipped with a wheel base having the same structure as the wheel base (52a). A passage (not shown) for supplying grinding water is also installed in the wheel base, wheel mount (48), spindle (42), etc. of the finishing grinding unit (36b). Additionally, a grinding water supply unit (not shown) is connected to one end of the passage.

[0045] A plurality of finishing grinding stones are installed on the lower side of the wheel base of the finishing grinding wheel (50b). The plurality of finishing grinding stones are arranged in an annular shape along the circumference of the lower side of the wheel base, with gaps formed between adjacent finishing grinding stones.

[0046] The abrasive particles of the finishing grinding wheel have an average particle size smaller than the abrasive particles of the rough grinding wheel (54a). However, there are no special restrictions on the binder or the material of the abrasive particles of the finishing grinding wheel, and they can be appropriately selected according to the specifications of the finishing grinding wheel.

[0047] An unloading arm (56) is installed in front of the loading / unloading area (A), and also in an area adjacent to the X-axis direction of the loading arm (14). A spinner cleaning unit (58) for cleaning and drying the workpiece (11) after grinding is installed in front of the unloading arm (56).

[0048] The grinding device (2) is equipped with a control unit (not shown) that controls the operation of the components. The control unit controls the operation of the positioning table (12), loading arm (14), turntable (16), chuck table (18), rough grinding unit (36a), finishing grinding unit (36b), unloading arm (56), spinner cleaning unit (58), etc.

[0049] The control unit is composed of a computer including, for example, a processing unit such as a CPU (Central Processing Unit), a main memory such as DRAM (Dynamic Random Access Memory), and an auxiliary storage device such as flash memory and a hard disk drive. The functions of the control unit are realized by operating the processing unit, etc., according to software stored in the auxiliary storage device.

[0050] Next, with reference to FIGS. 1 and FIGS. 2, the grinding chamber of the grinding device (2) will be described. FIGS. 2 is a partial cross-sectional side view of the grinding chamber. As shown in FIGS. 1, a prismatic cover member (60a) formed of metal is installed above the rough grinding area (B).

[0051] The cover member (60a) forms a rough grinding room (processing room) (62a) that separates the rough grinding area (B) from the incoming / outgoing area (A) and the finishing grinding area (C). The cover member (60a) has a plurality of side plates and a top plate to cover a chuck table (18) located in the rough grinding area (B) and a part of the rough grinding unit (36a) [wheel mount (48), rough grinding wheel (50a), etc.].

[0052] A first opening (not shown) is formed in the top plate of the cover member (60a) for the spindle (42) to pass through. Since the diameter of the first opening is slightly larger than the diameter of the spindle (42), the inner circumference of the first opening does not come into contact with the outer circumference of the spindle (42).

[0053] A second opening is formed in the rear side plate of the cover member (60a), and an exhaust duct (64a) made of metal is connected to this second opening. The exhaust duct (64a) is a curved cylindrical duct and has a cavity [i.e., an exhaust path (70a)] with an inner diameter of 90 mm.

[0054] One end of the exhaust path (70a) is connected to a grinding room (62a). Additionally, the other end of the exhaust path (70a) is connected to an exhaust unit (68) including a suction source (66), such as a fan, and a filter (not shown).

[0055] On the side of the exhaust duct (64a), a through opening (opening) (72a) is formed that penetrates a part of the exhaust duct (64a). The through opening (72a) of the present embodiment has a cylindrical shape, and the length of the through opening (72a) (i.e., the height of the circumference) is approximately equal to the thickness of the wall constituting the exhaust duct (64a).

[0056] Additionally, the size of the through opening (72a) (i.e., the diameter of the cylinder) is sufficiently small to reduce the impact of sudden pressure changes in the exhaust path (70a) on the box body (74a). The through opening (72a) of this embodiment has a diameter of 0.2 mm [0.22% of the diameter of the exhaust duct (64a)].

[0057] However, the through opening (72a) may have any diameter of 0.1 mm or more and 0.5 mm or less [i.e., about 0.11% or more and about 0.56% or less of the diameter of the exhaust duct (64a)]. Within this range, the impact of sudden pressure changes in the exhaust path (70a) on the box body (74a) can be reduced.

[0058] With respect to the through opening (72a), on the side opposite to the exhaust path (70a), a hollow box body (74a) formed of the same metal material as the exhaust duct (64a) is installed. The box body (74a) is connected to the exhaust path (70a) through the through opening (72a).

[0059] A pressure sensor (76a) for detecting the pressure inside the box body (74a) is installed in the box body (74a). Various pressure sensors, such as piezoresistive and capacitive types, are used as the pressure sensor (76a). When the pressure sensor (76a) detects that the pressure inside the box body (74a) falls below a predetermined threshold value (e.g., -100 Pa), it sends a predetermined signal to the aforementioned control unit.

[0060] When the control unit receives a predetermined signal from the pressure sensor (76a), it operates an alarm notification unit (not shown), such as an alarm lamp, buzzer, or monitor, attached to a case (not shown) on the base (4), and emits an alarm.

[0061] Above the finishing grinding area (C), a cover member (60b) identical to the cover member (60a) (see FIG. 1) is installed. The cover member (60b) forms a grinding chamber (processing chamber) (62b) for finishing grinding.

[0062] The cover member (60b) has a plurality of side plates and a top plate to cover a chuck table (18) located in the finishing grinding area (C) and a part of the finishing grinding unit (36b) [wheel mount (48), finishing grinding wheel (50b), etc.]. A first opening through which the spindle (42) passes is also formed in the top plate of the cover member (60b).

[0063] Additionally, a second opening (not shown) is formed in the rear side plate of the cover member (60b), and an exhaust duct (64b) formed of metal is connected to this second opening. Since the exhaust duct (64b) has approximately the same shape, structure, and function as the exhaust duct (64a), a detailed description is omitted.

[0064] An exhaust path having the same shape as the exhaust path (70a) is also formed inside the exhaust duct (64b). Additionally, a through opening (not shown) having the same shape as the through opening (72a) is formed on the side of the exhaust duct (64b).

[0065] With respect to the through opening of the exhaust duct (64b), a box body (not shown) identical to the box body (74a) is installed on the side opposite to the exhaust path of the exhaust duct (64b). Inside this box body, a pressure sensor (not shown) identical to the pressure sensor (76a) is also installed.

[0066] However, a turntable (16) is placed on the bottom of the grinding room (62a, 62b). Figure 3 (A) is a top view of the turntable (16). On the top surface of the turntable (16), a plurality of partition plates (78) are installed to divide the circular turntable (16) into approximately three parts.

[0067] Each partition plate (78) is connected to one another near the center of the upper surface of the turntable (16) and is formed from near the center of the upper surface of the turntable (16) to the outer periphery. Figure 3 (B) is a perspective view of the turntable (16).

[0068] The partition plate (78) protrudes a predetermined length from the upper surface of the turntable (16). When the turntable (16) is stopped, the upper portion of each partition plate (78) is slightly separated from the bottom portion of the adjacent cover member (60a) and cover member (60b) side plate in the Z-axis direction (see FIG. 2).

[0069] Next, the procedure for grinding a workpiece (11) using a grinding device (2) is described. First, a conveyor robot (6) conveys the workpiece (11) from a cassette (10a) to a positioning table (12). After the position of the workpiece (11) is adjusted on the positioning table (12), a loading arm (14) conveys the workpiece (11) to a chuck table (18) located in an incoming / outgoing area (A).

[0070] At this time, the workpiece (11) is placed on the holding surface (18a) such that the back side of the workpiece (11) faces upward. Then, the surface side of the workpiece (11) is sucked and held by the holding surface (18a). After that, the turntable (16) is rotated clockwise.

[0071] Accordingly, the chuck table (18) holding the workpiece (11) moves to the rough grinding area (B). In the rough grinding area (B), the chuck table (18) and the spindle (42) of the rough grinding unit (36a) are rotated respectively. Then, the rough grinding unit (36a) is ground and transported while supplying grinding water to the rough grinding wheel (54a).

[0072] As shown in FIG. 2, when the rough grinding wheel (54a) contacts the back side of the workpiece (11), the back side is rough ground (processed). During grinding, by operating the suction source (66), the air pressure in the grinding chamber (62a) and the exhaust path (70a) is lower than atmospheric pressure (i.e., negative pressure).

[0073] The air pressure in the grinding chamber (62a) and the exhaust path (70a) is adjusted to a negative pressure (i.e., -110 Pa [gauge]) that is, for example, 110 Pa lower than atmospheric pressure. In this way, by making the grinding chamber (62a) and the exhaust path (70a) negative pressure, the fine grinding water or powder-like processing debris is discharged to the outside of the grinding device (2) through the exhaust path (70a), etc.

[0074] After rough grinding is finished, the operation of the suction source (66) is stopped first. Next, the turntable (16) is rotated clockwise by about 120 degrees, for example, taking about 1.3 seconds, so that the chuck table (18) located in the rough grinding area (B) moves to the finishing grinding area (C).

[0075] When the turntable (16) rotates, as shown in FIG. 4, a gap is created between the upper part of the partition plate (78) and the lower part of the cover member (60a), so that the grinding chamber (62a, 62b) is temporarily opened to the atmosphere of the atmosphere in the standby or clean room.

[0076] FIG. 4 is a partial cross-sectional side view of a grinding chamber (62a), etc., according to the present embodiment, showing the grinding chamber (62a) temporarily open. In addition, in the present specification, the temporary opening of the grinding chambers (62a, 62b) means an opening caused by the rotation of the turntable (16), for example, an opening for a time of 1 second or more and 3 seconds or less.

[0077] By temporarily opening the grinding chamber (62a), air is introduced into the grinding chamber (62a), and the magnitude of the negative pressure in the exhaust path (70a) is temporarily reduced. That is, the pressure in the exhaust path (70a) is temporarily raised to approach atmospheric pressure.

[0078] However, as described above, since the through opening (72a) connecting the exhaust path (70a) and the box body (74a) is sufficiently small, it is difficult for a sudden change in pressure in the exhaust path (70a) to reach the box body (74a). As a result, the negative pressure inside the box body (74a) is maintained in the range of -100 Pa to -120 Pa, although its magnitude is slightly reduced.

[0079] Therefore, the pressure sensor (76a) normally monitors the pressure of the exhaust path (70a), but is not easily affected by a temporary decrease in the magnitude of the negative pressure of the exhaust path (70a). Therefore, even if the magnitude of the negative pressure of the exhaust path (70a) is temporarily reduced, the grinding device (2) does not emit an alarm.

[0080] In addition, since the same phenomenon occurs in the through opening formed on the side of the exhaust duct (64b), the grinding device (2) does not emit an alarm even if the magnitude of the negative pressure in the exhaust path of the exhaust duct (64b) is temporarily reduced. Therefore, unnecessary alarms in the grinding device (2) can be reduced.

[0081] Next, in the finishing grinding area (C), finishing grinding (processing) is performed while supplying grinding water to the back side of the workpiece (11). After the finishing grinding is finished, the operation of the suction source (66) is stopped first. Next, the turntable (16) is rotated counterclockwise for, for example, about 2.6 seconds.

[0082] Accordingly, the chuck table (18) located in the finishing grinding area (C) is moved to the receiving and discharging area (A). However, even when the turntable (16) is rotated, the magnitude of the negative pressure between the exhaust path (70a) and the exhaust path of the exhaust duct (64b) is temporarily reduced by the temporary opening of the grinding chambers (62a and 62b).

[0083] However, as described above, in this embodiment, the magnitude of the negative pressure within the box body (74a) does not decrease easily. Likewise, the magnitude of the negative pressure within the box body of the exhaust duct (64b) does not decrease easily. Therefore, unnecessary alarms in the grinding device (2) can be reduced.

[0084] The workpiece (11) located on the chuck table (18) that has been returned to the loading / unloading area (A) is returned to the spinner cleaning unit (58) by the unloading arm (56), and after cleaning and drying in the spinner cleaning unit (58), is returned to the cassette (10b) by the return robot (6).

[0085] Next, a comparative example is described. FIG. 5 is a partial cross-sectional side view of a grinding chamber (62a) according to a comparative example, showing the grinding chamber (62a) temporarily open. In the comparative example, the size of the through opening (82a) connecting the exhaust path (70a) and the box body (74a) is larger than the through opening (72a) described above.

[0086] The through opening (82a) has, for example, a cylindrical shape. The size of the through opening (82a) (i.e., the diameter of the circumference) is, for example, approximately the same as the inner diameter of the exhaust duct (64a). Due to the size of the through opening (82a), when the turntable (16) rotates, the magnitude of the negative pressure inside the box body (74a) is reduced to the same level as the exhaust path (70a).

[0087] Therefore, the pressure sensor (76a) is susceptible to the effect of a temporary decrease in the magnitude of the negative pressure in the exhaust path (70a). FIG. 6 is a schematic diagram illustrating the pressure change in the exhaust path (70a) when moving the chuck table (18) from the rough grinding area (B) to the finishing grinding area (C).

[0088] The horizontal axis represents time. t1 represents the timing for the start of rotation of the turntable (16), and t2 represents the timing for the stop of rotation of the turntable (16). The time from t1 to t2 is the rotation time of the turntable (16), for example, about 1.3 seconds.

[0089] The vertical axis represents negative pressure (Pa [gauge]) based on atmospheric pressure. Also, on the vertical axis, the magnitude of negative pressure increases as it goes down and decreases as it goes up. The graph (90) (solid line) of FIG. 6 shows the pressure change of the exhaust path (70a) according to the comparative example.

[0090] As shown in the graph (90) (solid line), the magnitude of the negative pressure inside the box body (74a) according to the comparative example decreases rapidly when the magnitude of the negative pressure in the exhaust path (70a) temporarily decreases. Therefore, the magnitude of the negative pressure inside the box body (74a) measured by the pressure sensor (76a) falls below -100 Pa [gauge] and decreases to about -70 Pa [gauge]. Accordingly, whenever the turntable (16) is rotated, the grinding device (2) emits an alarm.

[0091] In this regard, the graph (92) (dotted line) of FIG. 6 shows the pressure change of the exhaust path (70a) according to the above-described embodiment. As shown in the graph (92), the magnitude of the negative pressure inside the box body (74a) according to this embodiment does not fall below -100 Pa [gauge] even if the magnitude of the negative pressure in the exhaust path (70a) is temporarily reduced. Therefore, unnecessary alarms in the grinding device (2) can be reduced.

[0092] Furthermore, the structure, method, etc. according to the above embodiment may be appropriately modified and implemented as long as it does not deviate from the scope of the purpose of the present invention. In one example, in the above-described embodiment, the box body (74a) is directly connected to the side of the exhaust duct (64a), but the through opening (72a) of the exhaust duct (64a) and the box body (74a) may be connected through a connecting hose (not shown).

[0093] In this case, the inner diameter of the cross-section perpendicular to the longitudinal direction of the connecting hose is approximately the same diameter as the through opening (72a). Additionally, if the processing chamber, such as the grinding chamber (62a), is in a negative pressure atmosphere, the technical concept of the present invention may be applied to other processing devices.

[0094] Other processing devices include, for example, a grinding device. The grinding device comprises a grinding unit and a chuck table positioned below the grinding unit to suck in and hold the workpiece (11). The grinding unit has a spindle and a grinding pad wheel mounted on the lower end of the spindle.

[0095] The upper part of the chuck table of the grinding device is covered by a cover member. The cover member has a plurality of side plates and a top plate to cover the chuck table and a part of the grinding unit. The cover member constitutes a grinding chamber (processing chamber).

[0096] An opening is formed in the upper plate of the cover member for a spindle to pass through. The diameter of the opening is slightly larger than the diameter of the spindle. Another opening is formed in the rear side plate of the cover member, and an exhaust duct made of metal is connected to the other opening.

[0097] When grinding the workpiece (11), the grinding chamber is made into a negative pressure atmosphere, and the mist-like grinding water (processing water) formed inside the grinding chamber is exhausted through an exhaust duct connected to the grinding chamber. Additionally, the chuck table of the grinding device may be placed on a part of the turntable (16) to form a grinding device (processing device). Explanation of the symbols

[0098] 2 : Grinding device 4 : Base 4a : Concave part 6 : Return robot 8a, 8b: Cassette placement area 10a, 10b: Cassette 11 : Workpiece 12 : Positioning table 14: Loading arm 16: Turntable 18 : Chuck table 18a : Retention surface 22a, 22b: Support structure 24: Grinding feed unit 26: Z-axis guide rail 28: Z-axis moving plate 30 : Z-axis ball screw 32 : Z-axis pulse motor 36a: Rough grinding unit 36b: Finish grinding unit 38: Retaining member 40: Spindle housing 42 : Spindle 44 : Motor 48 : Wheel mount 50a : Rough grinding wheel 50b: Finish grinding wheel 52a: Wheelbase 54a : Jo Yeon-sak Jiseok 56 : Unloading Aam 58: Spinner cleaning unit 60a, 60b: Cover member 62a, 62b: Grinding room 64a, 64b: Exhaust duct 66 : Intake source 68 : Exhaust unit 70a: Exhaust path 72a: Penetrating opening 74a: Box body 76a: Pressure sensor 78 : Partition plate 82a : Through opening 90, 92 : Graph A : Inbound / Outbound Area B: Rough grinding area C: Finish grinding area

Claims

Claim 1 A machining device for machining a workpiece held by a chuck table while supplying machining fluid to the workpiece and machining the workpiece with a machining unit having a spindle, comprising a top plate and a plurality of side plates, a cover member covering a part of the chuck table and the machining unit, an exhaust duct connected to the cover member, and a disc-shaped turntable disposed below the top plate of the cover member, wherein the chuck table is disposed on the upper surface side and the turntable comprises a plurality of partition plates protruding from the upper surface of the turntable, wherein when the turntable is stopped, the plurality of partition plates are disposed below each corresponding side plate among the plurality of side plates, wherein when the turntable is stopped, a space defined by at least the cover member, the upper surface of the turntable, and the plurality of partition plates is maintained at a predetermined negative pressure, but when the space is opened by the rotation of the turntable, the pressure in the space increases, and the exhaust duct comprises an exhaust path in which one end is connected to the cover member and the other end is connected to an exhaust unit having a suction source, and through an opening formed on the side of the exhaust duct A processing device characterized by having a box body that communicates with the exhaust path and includes a pressure sensor inside, wherein the opening has a diameter of 0.11% or more and 0.56% or less of the inner diameter of the exhaust duct. Claim 2 A processing device according to claim 1, characterized by including a control unit that controls the operation of the processing unit and the turntable.

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