Air nozzle, shape measuring device, dicing device, and nozzle adjustment method

Abstract

This invention provides a nozzle adjustment method that allows for easy confirmation and adjustment of the direction of direction of an air nozzle attached to a microscope. [Solution] The air nozzle 70 has an air supply passage 90 through which supplied air flows, and comprises a main body 102 that is assembled to the microscope 30, a linear discharge section 104 provided on the outlet side of the air supply passage 90 in the main body 102, and an adjustment mechanism for adjusting the position and orientation of the main body 102 relative to the microscope 30 so that the direction of the discharge section 104 is directed toward the focal point P of the microscope 30. The main body has a light guide path 114 that communicates with the air supply passage 90 and guides light incident from the outlet 112 of the discharge section 104 into the interior.

Description

Technical Field

[0001] The present invention relates to an air nozzle assembled to a microscope for observing grooves on a wafer, and particularly to a nozzle adjustment method for adjusting the position and orientation of the air nozzle.

Background Art

[0002] A wafer on which a large number of devices are formed in the pre-process of semiconductor manufacturing is divided into a plurality of chips for each device in the dicing process. A plurality of devices are formed on the surface of the wafer, and each device is partitioned by a division planned line called a street. In the dicing process, by rotating a blade called a dicing saw at high speed, cutting is performed along the street, and the devices are divided. Grooves (hereinafter also referred to as "kerfs") are formed on the surface of the wafer by the cuts.

[0003] By the way, in recent years, the requirements for miniaturization and downsizing of semiconductor wafers have been increasing, and a device that advances cutting while adjusting the cutting position in the dicing process is also known (see Patent Document 1). Such a dicing device includes a high-magnification microscope, images the kerf formed on the wafer, and detects its position and shape.

[0004] On the other hand, an air nozzle capable of discharging air toward the kerf is assembled to the microscope. In the dicing process, cutting water is supplied so that cutting chips do not adhere to the surface of the wafer during cutting, and a water film is formed on the surface of the wafer. Therefore, after blowing off the cutting water accumulated in the kerf by air blowing, imaging of the kerf by the microscope is performed. By removing the water film in this way, distortion of the image captured by the microscope is suppressed, and high-precision image processing is realized.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] As mentioned above, when performing cutting while detecting the kerf formed on the wafer during the dicing process, efficiently removing the water film by air blowing contributes to the overall efficiency of the dicing process. To achieve this, it is necessary to set the direction of the air nozzle relative to the wafer with high precision.

[0007] This invention has been made in view of these circumstances, and one of its objectives is to provide a nozzle adjustment method that allows for easy confirmation and adjustment of the direction of direction of an air nozzle attached to a microscope. [Means for solving the problem]

[0008] One aspect of the present invention is an air nozzle for discharging air, which is attached to a microscope for observing grooves formed in a wafer by dicing. The air nozzle has an air supply path through which supplied air flows, and comprises a main body attached to the microscope, a linear discharge section provided on the outlet side of the air supply path in the main body, and an adjustment mechanism for adjusting the position and orientation of the main body relative to the microscope so that the direction of the discharge section is directed toward the focal point of the microscope. The main body has a light guide path that communicates with the air supply path and guides light incident from the outlet of the discharge section into the interior.

[0009] Another aspect of the present invention is a shape measuring device for measuring the shape of grooves formed in a wafer by dicing. This shape measuring device comprises a microscope for measuring the shape of grooves and an air nozzle for discharging air, which is attached to the microscope. The microscope includes a light source for emitting measurement light and an objective lens positioned on the optical axis. The air nozzle includes a body attached to the microscope, having an air supply path through which supplied air flows, a linear discharge section provided on the outlet side of the air supply path in the body, and an adjustment mechanism for adjusting the position and orientation of the body relative to the microscope so that the direction of the discharge section is directed toward the focal point of the microscope. The body has a light guide path that communicates with the air supply path and guides light incident from the outlet of the discharge section into the interior.

[0010] A further aspect of the present invention is a dicing apparatus. This dicing apparatus comprises a chuck table for holding a wafer, a blade for dicing the wafer held on the chuck table, a cutting fluid supply unit for supplying cutting fluid to the blade during the dicing process, a microscope for observing grooves formed in the wafer by dicing, and an air nozzle attached to the microscope for discharging air to remove cutting fluid adhering to the grooves during the dicing process. The microscope includes a light source for emitting observation light and an objective lens positioned on the optical axis. The air nozzle includes a body attached to the microscope, having an air supply path through which supplied air flows, a linear discharge section provided at the outlet end of the air supply path in the body, and an adjustment mechanism for adjusting the position and orientation of the body relative to the microscope so that the direction of the discharge section is directed toward the focal point of the microscope. The body has a light guide path that communicates with the air supply path and guides light incident from the outlet of the discharge section into the interior.

[0011] A further aspect of the present invention is a nozzle adjustment method for adjusting the position and orientation of an air nozzle in an apparatus comprising a microscope for observing grooves formed in a wafer by dicing, and an air nozzle attached to the microscope for discharging air to remove water adhering to the grooves. The air nozzle includes a main body attached to the microscope and having an air supply path through which supplied air flows, and a light guide path communicating with the air supply path, and a linear discharge section provided on the outlet side of the air supply path in the main body, the light guide path guiding light incident from the outlet of the discharge section. This nozzle adjustment method includes a moving step of moving the microscope so that the focal point is located in the grooves of the wafer, an irradiation step of irradiating light from the microscope toward the grooves of the wafer, and an adjustment step of adjusting the position and orientation of the main body relative to the microscope so that the direction of the discharge section is directed toward the focal point of the microscope. The adjustment step adjusts the position and orientation of the main body so that the intensity of the light guided into the light guide path by reflection of the microscope light from the grooves is increased. [Effects of the Invention]

[0012] According to the present invention, a nozzle adjustment method is provided that allows for easy confirmation and adjustment of the direction of direction of an air nozzle assembled to a microscope. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view showing the schematic configuration of a dicing apparatus according to an embodiment. [Figure 2] This is a perspective view showing the general configuration of the machining section. [Figure 3] This is a diagram showing the configuration of a microscope and its surroundings. [Figure 4] This is a diagram showing the configuration of a microscope and its surroundings. [Figure 5] This is a schematic diagram showing the structure of an air nozzle. [Figure 6] This is a perspective view showing the structure of the wafer after dicing. [Figure 7] This is a plan view of the wafer. [Figure 8] This diagram schematically represents air blowing using a nozzle. [Figure 9] It is a diagram showing a nozzle adjustment method. [Figure 10] It is a diagram showing a nozzle adjustment method. [Figure 11] It is a flowchart showing the adjustment procedure of the air nozzle. [Figure 12] It is a diagram schematically showing the configuration of the air nozzle according to Modification 1. [Figure 13] It is a flowchart showing the adjustment procedure of the air nozzle according to Modification 2. [Figure 14] It is a flowchart showing the adjustment procedure of the air nozzle according to Modification 3.

Mode for Carrying Out the Invention

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following embodiments and their modifications, substantially the same components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0015] The dicing device of the present embodiment includes a microscope for observing a kerf formed on a wafer and an air nozzle for removing a water film attached to the kerf. The air nozzle is provided with a light guide path communicating with the air supply path. When light is irradiated onto the surface of the wafer from the microscope, a part of the reflected light enters the air supply path and is guided to the light guide path. The user adjusts the position and orientation of the air nozzle so that the intensity of the light guided to the light guide path increases. Thereby, the pointing direction of the air nozzle can be appropriately set. Details thereof will be described below.

[0016] (Overall Configuration of Dicing Device) FIG. 1 is a perspective view showing a schematic configuration of a dicing device according to an embodiment. Hereinafter, for convenience of explanation, the front-rear direction, left-right direction, and up-down direction of the dicing device as viewed from the front will be described as the X direction, Y direction, and Z direction, respectively.

[0017] The dicing apparatus 1 comprises a load port 10, a transport mechanism 12, a processing unit 14, and a cleaning unit 16. A cassette containing multiple wafers W is placed on the load port 10. The transport mechanism 12 transports the wafers W to each part of the apparatus. The processing unit 14 performs dicing on the wafers W. The cleaning unit 16 spin-cleans the diced wafers W. A control unit 20 is provided inside the housing 18 of the dicing apparatus 1.

[0018] The control unit 20 consists of a general-purpose computer and includes a CPU for executing various calculation processes, memory or storage for storing control programs, memory used as a work area for data storage and program execution, input / output interfaces, etc. The control unit 20 controls each functional part (mechanism and device) of the dicing device 1 according to the control program.

[0019] The wafer W is stored in a cassette while being held in the frame 22. The transport mechanism 12 takes the unprocessed wafer W stored in the cassette and transports it to the processing unit 14. The processing unit 14 performs dicing (cutting) on ​​the wafer W to divide the device. At this time, kerfs are formed on the surface of the wafer by cuts. After that, the wafer W is transported by the transport mechanism 12 to the cleaning unit 16 and cleaned. Then, it is transported by the transport mechanism 12 to the load port 10 and stored in the cassette.

[0020] Figure 2 is a perspective view showing the schematic configuration of the machining section 14. The processing unit 14 is a so-called twin-spindle dicer and includes a pair of blades 24, a workpiece holding unit 26 for holding the wafer W, an alignment microscope 28, and a shape measurement microscope 30. The blades 24 are disc-shaped dicing saws.

[0021] Each blade 24 is covered by a cover that has a nozzle for supplying cutting fluid. This nozzle is connected to a cutting fluid supply unit 25 via piping. The cutting fluid supply unit 25 includes a cutting fluid source (tank), a pump, and a flow control valve, but details will not be explained here. The control unit 20 controls the cutting fluid supply unit 25, supplying cutting fluid to each nozzle. The microscope 30 functions, for example, as a white light interferometer (details will be described later). Note that the microscope 30 may function as something other than a white light interferometer, for example, as a laser displacement meter.

[0022] A pair of blades 24 are arranged opposite each other in the Y direction and are rotatably supported by a spindle 32. The blades 24 have a rotation axis extending in the Y direction. The spindles 32 have a built-in high-frequency motor that rotates the blades 24 at high speed around the rotation axis. Each spindle 32 is supported so as to be movable in the Y and Z directions by a moving mechanism described later.

[0023] The workpiece holding section 26 includes a chuck table 34, a rotary table 36, and an X table 38. The chuck table 34 has a holding surface 34a for adsorbing and holding a wafer W. The holding surface 34a is provided with numerous adsorption holes through which a vacuum is applied to adsorb the back surface of the wafer W. By driving a vacuum adsorption source (not shown), the wafer W can be adsorbed and fixed to the holding surface 34a.

[0024] A base 40 is provided on the base (not shown) of the dicing apparatus 1, and a pair of guide rails 42 extending in the X direction are provided on the upper surface of the base 40. The X table 38 is installed horizontally so that it can move in the X direction along the guide rails 42. The X table 38 is driven by an X movement mechanism 44. In this embodiment, the X movement mechanism 44 is implemented by a linear motor, but it may also be implemented by a screw feed mechanism and a servo motor that drives it.

[0025] The rotary table 36 is rotatably supported by the X table 38, and the chuck table 34 is fixed to the upper surface of the rotary table 36. The rotary table 36 can rotate around its own axis (in the θ direction around the axis L extending in the Z direction) by a rotation mechanism 46. The rotation mechanism 46 is implemented, for example, by a spindle motor. With this configuration, the chuck table 34 is movable in the X direction and the θ direction.

[0026] On the other hand, an arch-shaped column 50 is erected on the base, and the column 50 supports a pair of blades 24, a microscope 28, and a microscope 30. Specifically, a pair of guide rails 52 extending in the Y direction are provided on the front of the column 50, and a pair of Y tables 54 are installed so that they can move in the Y direction along the guide rails 52. The Y tables 54 are driven by a Y movement mechanism 56. The Y movement mechanism 56 is realized, for example, by a screw feed mechanism and a servo motor that drives it, and the pair of Y tables 54 can be driven individually.

[0027] Each Y-table 54 is provided with a pair of guide rails 58 extending in the Z direction on its front surface, and a pair of Z-tables 60 are positioned to move in the Z direction along the guide rails 58. The Z-tables 60 are driven by a Z-movement mechanism 62. The Z-movement mechanism 62 is implemented, for example, by a screw feed mechanism and a servo motor that drives it.

[0028] In the above configuration, the X-movement mechanism 44, the Y-movement mechanism 56, the Z-movement mechanism 62, and the rotation mechanism 46 function as "movement mechanisms" that move the microscopes 28, 30 and the chuck table 34 (i.e., the wafer W) relative to each other, and also move the pair of blades 24 and the chuck table 34 relative to each other.

[0029] The microscope 28 is mounted on the Z-table 60 integrally with the spindle 32 and is held to move freely in the Y and Z directions. The microscope 28 is an imaging device (camera) that incorporates an image sensor and optical system (not shown) and images the surface of the wafer W. The image captured by the microscope 28 is used for alignment between the wafer W and the blade 24.

[0030] The microscope 30 is mounted on the Z-table 60 integrally with the spindle 32 and is held independently of the microscope 28 so as to be movable in the Y and Z directions. The microscope 30 images the kerf formed on the wafer W during the dicing process. The images captured by the microscope 30 are used for measuring the shape of the kerf (measuring processing quality). The microscope 30 has a higher magnification than the microscope 28.

[0031] (Arrangement configuration of microscope and air nozzle) Figures 3 and 4 illustrate the configuration of the microscope 30 and its surroundings. Figure 3 is a perspective view, and Figure 4 is a front view. In Figure 3, for ease of explanation, the microscope 30 is shown with its cover partially removed.

[0032] As shown in Figure 3, an air nozzle 70 is attached to the microscope 30. The air nozzle 70 discharges air to remove cutting fluid adhering to the grooves before measuring the shape of the kerf formed in the dicing process. The microscope 30 and the air nozzle 70 constitute a "shape measuring device" for measuring the shape of the kerf formed on the wafer W by dicing.

[0033] The microscope 30 comprises a housing 72 that incorporates an optical mechanism and a lens unit 74 provided at the lower end of the housing 72. The lens unit 74 includes an objective lens, etc., as described later. An air nozzle 70 is positioned to the side of the lens unit 74. A lifting mechanism 76 for moving the air nozzle 70 in the Z direction is provided on one side of the housing 72. The lifting mechanism 76 includes a support member 78 to which the air nozzle 70 is attached, a pair of arms 80 that support the support member 78, and an air cylinder 82 that drives the pair of arms 80 in the Z direction. The height of the air nozzle 70 can be adjusted by driving the air cylinder 82. In this embodiment, the lifting mechanism for the air nozzle 70 is realized by an air cylinder, but it may also be realized by a screw feed mechanism and a servo motor that drives it.

[0034] The support member 78 extends in the Y direction, and its base end is fixed to a pair of arms 80. An air nozzle 70 is attached to the tip of the support member 78 so as to hang down. The air nozzle 70 is fixed to the support member 78 by two screws 84, but the connection between the air nozzle 70 and the support member 78 has a fitting structure with some play in the fitting (that is, the upper end of the air nozzle 70 is loosely fitted to the lower surface of the support member 78). As a result, the air nozzle 70 can be displaced in the X and Y directions within the range of this play relative to the support member 78, and can also be rotated around the axis L1 in the Z direction (θ direction).

[0035] As shown in Figure 4, the microscope 30 has a cover 86 capable of housing the lens unit 74 and the air nozzle 70. A passage 88 for circulating air is formed at the tip of the support member 78. One end of the passage 88 communicates with the air supply passage 90 of the air nozzle 70, and a pipe fitting 92 is connected to the other end. A pipe 96 extending from the air supply section 94 is connected to the pipe fitting 92.

[0036] The air supply unit 94 includes an air supply source 98 and an on-off valve 100. The air supply source 98 has a tank for storing pressurized air. The on-off valve 100 is a solenoid valve, and by opening the on-off valve 100, pressurized air can be supplied to the air nozzle 70. The control unit 20 controls the driving of the on-off valve 100. Pressurized air (air jet AJ) is discharged from the discharge section 104 of the air nozzle 70 and supplied to the surface of the wafer W.

[0037] Figure 5 is a schematic diagram of the structure of the air nozzle 70. Figure 5(A) is a perspective view, and Figure 5(B) is a longitudinal cross-sectional view. For the sake of explanation, the side from which air is discharged by the air nozzle 70 may be referred to as the "front," and the opposite side as the "rear."

[0038] As shown in Figure 5(A), the air nozzle 70 has a main body 102 that is roughly rectangular in plan view and front view, and a discharge section 104 assembled to the lower part of the main body 102. The discharge section 104 consists of a straight tubular member. A guide section 103 is provided at the lower part of the main body 102, projecting diagonally downward (forward). The guide section 103 is provided with a mounting hole 105 that opens diagonally downward. The discharge section 104 is attached to the mounting hole 105 so as to be directed diagonally downward. The discharge section 104 may be configured to allow adjustment of extension and retraction in the direction of direction of direction.

[0039] As shown in Figure 5(B), an air supply passage 90 is formed through the main body 102 to allow air supplied from the air supply unit 94 to flow through. The air supply passage 90 includes a straight first passage 106 extending vertically and a straight second passage 108 extending diagonally downward. The connection between the first passage 106 and the second passage 108 is located at the bottom of the main body 102. The tip of the second passage 108 communicates with the mounting hole 105. As a result, the internal passage of the discharge unit 104 and the air supply passage 90 are in communication. Air introduced from the inlet 110 of the air supply unit 94 is discharged from the outlet 112 (also called the "discharge port") of the discharge unit 104 after passing through the first passage 106 and the second passage 108.

[0040] On the side of the second passage 108 opposite the discharge section 104, a straight light guide path 114 is provided that opens toward the rear. The light guide path 114 has a connection section 116 to the air supply passage 90 at one end and an opening 118 at the other end that opens toward the outside of the main body 102, and is provided coaxially with the discharge section 104 and the second passage 108. The outlet 112 of the discharge section 104 and the opening 118 are arranged in a straight line. The light guide path 114 communicates with the discharge section 104 in the axial direction and is a passage that guides the light introduced from the outlet 112 of the discharge section 104 to the opening 118 (details will be described later).

[0041] The opening 118 can be closed by the closing member 120. In this embodiment, the closing member 120 is made of a male screw, and the opening 118 has a female screw that can be screwed into the male screw. Therefore, the closing member 120 can be attached to and detached from the main body 102 using this screw structure, and the opening 118 can be opened and closed. In a modified example, after nozzle adjustment as described later, the closing member may be fixed to the main body 102 by press-fitting, crimping or other fixing means to close the opening 118.

[0042] A pair of screw holes 122 are provided on the upper surface of the main body 102, flanking the inlet 110 of the air supply unit 94. On the other hand, the support member 78 is provided with mounting holes for screws 84 at positions opposite to the pair of screw holes 122 (see Figure 3). The air nozzle 70 can be fixed to the support member 78 by screwing the screws 84 into the screw holes 122 and fastening them.

[0043] (Air blowing onto the wafer) Figure 6 is a perspective view showing the structure of wafer W after dicing. Through the dicing process, a lattice-shaped kerf K (groove) is formed on the wafer W, surrounding each of the multiple devices D. A dicing tape 23 is attached to the back surface of the wafer W, and the peripheral edge of the dicing tape 23 is fixed to an annular frame 22. The wafer W is fixed to a chuck table 34 via the frame 22 (see Figure 1).

[0044] Figure 7 is a plan view of wafer W. Figure 7(A) shows the wafer before dicing, and Figure 7(B) shows it after dicing. Figure 7(C) is an enlarged view of section A in Figure 7(B). Note that this figure is a schematic diagram for ease of understanding, and the chips and other components on wafer W are depicted larger than they actually are.

[0045] As shown in Figure 7(A), two mutually orthogonal streets S1 and S2 are set on the surface of the wafer W as planned division lines. Street S1 extends in the X direction, and street S2 extends in the Y direction. Multiple such streets S1 and S2 are set on the surface of the wafer W and arranged in a grid pattern. Device D is formed within the regions demarcated by these streets S1 and S2.

[0046] As shown in Figure 7(B), dicing is performed along these streets S1 and S2, and a kerf K is formed so as to pass through the center of each street S1 and S2 in the width direction. In this embodiment, since the widths of streets S1 and S2 are the same, they are collectively referred to as "street S" unless specifically distinguished between them. As shown in Figure 7(C), street S is a boundary that demarcates adjacent devices D, and the kerf K is formed within the range of street S. The width of the kerf K (kerf width Wk) is, for example, several tens of micrometers, which is smaller than the width of street S (street width Ws).

[0047] Thus, a street S is set on the wafer W, and in the dicing process, it is necessary to perform cutting with high precision so that a kerf K is formed within the street width Ws. For this reason, measuring the shape of the kerf K with a microscope 30 is important, and prior to that, it is necessary to remove the water film with an air nozzle 70 reliably and quickly. Therefore, it is preferable that the position and orientation of the air nozzle 70, which are adjusted in advance, can be easily performed.

[0048] In this embodiment, the shape and position of the kerf K, including the groove width, are observed using the microscope 28 in order to adjust so that the kerf K is formed within the range of the street S. On the other hand, the microscope 30 measures the internal shape of the kerf K, which is located deeper than the surface of the wafer W. Specifically, when performing multi-stage machining (for example, machining a first groove on the surface of the wafer using a thick blade, and then machining a second groove on the bottom surface of the first groove using a thin blade), the upper stage machined with the thick blade is easy to observe, but the lower stage machined with the thin blade is difficult to observe. The microscope 30 is particularly suitable for observing the lower stage.

[0049] Figure 8 schematically illustrates air blowing by a nozzle. Figure 8(A) is a perspective view showing the air blowing process. The white arrows in the figure indicate the relative direction of movement of the air nozzle with respect to the wafer W. Figure 8(B) is a cross-sectional view along the vertical plane Fv of Figure 8(A).

[0050] As shown in Figure 8(A), when performing air blowing, the control unit 20 controls the driving of the air supply unit 94 and each moving mechanism to perform air blowing along the kerf K. By driving the X-movement mechanism 44, the air nozzle 70 and the wafer W are moved relative to each other in the X direction, thereby moving the air jet AJ in the longitudinal direction of the kerf K. At this time, the air nozzle 70 (discharge unit 104) is moved relative to the wafer W along the vertical plane Fv containing the kerf K, while discharging the air jet AJ.

[0051] As shown in Figure 8(B), the air nozzle 70 (specifically, the axis L3 of the discharge unit 104) is set to make a predetermined inclination angle θ1 (for example, 45 degrees) with respect to the surface of the wafer W. The air nozzle 70 discharges an air jet AJ diagonally downward toward the forward direction of travel relative to the wafer W. Therefore, the cutting fluid CW adhering to the surface of the wafer W can be discharged from the kerf K in a manner that pushes it forward.

[0052] (Nozzle adjustment method) Figures 9 and 10 illustrate the nozzle adjustment method. Figure 9 shows the positional relationship between the microscope 30 and the air nozzle 70. Figure 10 shows the method for adjusting the position and orientation of the air nozzle 70, and shows the air nozzle 70 viewed from above.

[0053] As described above, when measuring the shape of the kerf K using the microscope 30, the water film is removed by the air nozzle 70 prior to the measurement. In order to efficiently remove this water film, the position and orientation of the air nozzle 70 must be adjusted with high precision. In this embodiment, the positional relationship between the microscope 30 and the air nozzle 70 is utilized to facilitate this adjustment.

[0054] Specifically, focusing on the fact that the focal point P of the microscope 30 is set on the surface of the wafer W (the bottom surface of the calf K), the position and orientation of the air nozzle 70 are adjusted so that the direction of the air nozzle 70 (i.e., the direction of air discharge) is directed toward the focal point P. The appropriateness of this adjustment is determined by observing the scattered light of the light irradiated from the microscope 30 onto the wafer W along the axis of the discharge unit 104. For this purpose, the light guide path 114 of the air nozzle 70 described above is used. The details are explained below.

[0055] First, let's describe the configuration of the microscope 30 and its surroundings. As shown in Figure 9, the microscope 30 is a so-called Mirau-type white light interferometer and includes a beam splitter BS1, an objective lens 124, a glass plate 126, and a beam splitter BS2. The beam splitter BS1 is located in the center of the housing 72. Inside the lens unit 74, the objective lens 124, the glass plate 126, and the beam splitter BS2 are arranged from above. A reference mirror 128 is provided in the center of the glass plate 126. In addition, a white light source 130 is provided on the side of the housing 72, and an imaging unit 132 is provided on the top surface of the housing 72.

[0056] The white light source 130 emits white light toward the beam splitter BS1 (see dashed line). A portion of this white light is reflected by the beam splitter BS1 and guided to the objective lens 124. The objective lens 124 is positioned on the optical axis L2 of the white light and focuses this white light to the focal point P. The focal point P is located on the optical axis L2 of the white light. That is, a portion of the white light that has passed through the objective lens 124 is guided to the focal point P by passing through the glass plate 126 and the beam splitter BS2. This white light is reflected by the surface of the wafer W and guided to the beam splitter BS1 as measurement light.

[0057] Meanwhile, a portion of the white light that has passed through the objective lens 124 is reflected by the beam splitter BS2 and guided to the reference mirror 128. This white light is reflected by the reference mirror 128 to become measurement light, which is then reflected again by the beam splitter BS2 and guided to the beam splitter BS1. These measurement light and reference light are combined (superimposed) by the beam splitter BS1, and the resulting interference light is detected by the imaging unit 132.

[0058] The optical path length of the reference light is constant, but the optical path length of the measurement light changes according to the vertical scanning of the microscope 30. When the difference in optical path lengths between the measurement light and the reference light is zero (including nearly zero), the intensity of the interference light (intensity of the interference signal) is maximized (see, for example, Japanese Patent Application Publication No. 2021-84200).

[0059] The imaging unit 132 is equipped with a two-dimensional image sensor in which multiple pixels (photodetectors) are arranged in two dimensions along the XY axis. A CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) is used as the photodetector. The imaging unit 132 captures the interference light that has passed through the beam splitter BS1 and outputs the interference signal for each pixel to the control unit 20.

[0060] The above-described lifting mechanism 76 is provided on the side of the housing 72, and the air nozzle 70 is supported so as to be able to move up and down in the Z direction. The housing 72 itself is also supported so as to be able to move up and down in the Z direction by a lifting mechanism (not shown). Therefore, the lens unit 74 can be moved forward below the cover 86 or retracted into the cover 86 (see Figure 4). By housing the lens unit 74 inside the cover 86, it is possible to prevent the lens unit 74 from being contaminated by scattered cutting fluid, etc.

[0061] In the above configuration, the microscope 30 is designed so that the optical path lengths of the measurement light and the reference light are equal when the focal point P is aligned with the surface of the wafer W (or the bottom surface of the calf K when imaging the calf K). At this time, the intensity of the reflected light (scattered light) reflected from the surface of the wafer W is also maximized. This embodiment utilizes this point to capture the light reflected in the direction of the ejection unit 104 and adjust the position and orientation of the air nozzle 70 so that the intensity of that light is maximized. This makes the destination point of the air ejected from the air nozzle 70 coincide with the focal point P. The structure of the air nozzle 70 is designed to easily achieve this adjustment.

[0062] Specifically, the mounting angle of the air nozzle 70 is adjusted so that the focusing point P is located on the axis L3 of the discharge unit 104. In this embodiment, this adjustment is performed manually by the user. That is, the microscope 30 is driven in the Z direction to align the focusing point P (focus) with the surface of the wafer W (or the bottom surface of the calf K in the case of calf K), and then the white light described above is irradiated. At this time, the white light is reflected from the surface of the wafer W, and a portion of the reflected light (scattered light) enters the air nozzle 70 from the outlet 112 of the discharge unit 104, passes through the light guide path 114, and is guided to the opening 118.

[0063] The user visually inspects the air nozzle 70 from the rear and adjusts its orientation so that the intensity of scattered light visible from the opening 118 is maximized. When the intensity of scattered light is deemed to be maximized, the user fixes the air nozzle 70 to the support member 78 with the screw 84 (see Figure 3). As described above, the connection between the air nozzle 70 and the support member 78 has a loose fitting structure, which allows for such fine adjustment of the air nozzle 70. In other words, the screw 84 and the loose fitting structure function as an "adjustment mechanism" for adjusting the position and orientation of the air nozzle 70 (main body 102) relative to the microscope 30 so that the direction of the discharge part 104 is directed toward the focusing point P.

[0064] When the air nozzle 70 is adjusted to the correct position (Figure 10(A)), the focusing point P is located on the axis L3. As described above, since the outlet 112 and the opening 118 of the discharge section 104 are aligned in a straight line, some of the scattered light reflected at the focusing point P travels straight along the axis L3 and enters the air nozzle 70 from the outlet 112, and is guided to the opening 118 without being obstructed by the internal structure of the air nozzle 70. As a result, the intensity of the light visible at the opening 118 is greatest, and it becomes the brightest.

[0065] On the other hand, if the air nozzle 70 is shifted from its proper position in the X or Y direction (Figure 10(B)), or if it is shifted from its proper position in the θ direction (Figure 10(C)), the scattered light reflected at the focal point P cannot enter the air nozzle 70 from the outlet 112, or even if it can enter, it cannot travel straight through the air nozzle 70. As a result, the light cannot be seen at the opening 118, or if it can be seen, the light intensity is low, resulting in a dim light. In other words, by adjusting (fine-tuning) the air nozzle 70 from an insufficiently adjusted state to the proper position, the axis L3 of the discharge section 104 can be brought closer to the focal point P. This means that the direction of the air nozzle 70's beam can be properly adjusted.

[0066] Next, the specific procedure for nozzle adjustment will be explained. Here, "nozzle adjustment" refers to fine-tuning the position and orientation of the air nozzle 70, assuming that rough adjustments are made beforehand during the blade 24 alignment correction stage. Since the discharge portion 104 of the air nozzle 70 and the blade 24 are designed to be parallel, only fine adjustments are necessary for nozzle adjustment.

[0067] Figure 11 is a flowchart illustrating the procedure for adjusting the air nozzle. Prior to nozzle adjustment, the control unit 20 controls the transport mechanism 12 to set the diced wafer W on the chuck table 34 (S10). Then, it controls each movement mechanism to move the microscope 30 to the adjustment position (S12: movement step). The "adjustment position" here refers to a position that is pre-set so that the focusing point P is located on the surface of the wafer W (the bottom surface of the kerf K) (see Figure 9).

[0068] Next, the control unit 20 drives the microscope 30 and irradiates white light onto the wafer W (kerf K) (S14: irradiation step). At this time, the air blow from the air nozzle 70 is stopped and the closing member 120 is removed. A portion of the light reflected by the kerf K (scattered light) enters the discharge unit 104.

[0069] The user visually inspects the opening 118 from behind the air nozzle 70 and adjusts the position and orientation of the air nozzle 70 so that scattered light is visible and the visible light is brightest (S16: adjustment step). Once the position with the brightest light is identified, the screw 84 is tightened to fix the air nozzle 70 to the support member 78.

[0070] As described above, in this embodiment, the main body 102 of the air nozzle 70 is provided with a light guide path 114 that communicates with the air supply passage 90. When adjusting the direction of direction of the air nozzle 70 (nozzle adjustment), light is shone from the microscope 30 toward the wafer W with the air blow stopped, and a portion of the reflected light enters from the outlet 112 of the air supply passage 90 and is guided to the light guide path 114. The user can visually observe the light guided to the light guide path 114 and emitted from the opening 118, and adjust the position and orientation of the air nozzle 70 so that the intensity of the light increases, thereby appropriately setting the direction of direction of the discharge section 104. In other words, the direction of direction of the air nozzle 70 can be easily confirmed and adjusted by simply utilizing the simple structure of a straight through-hole formed in the air nozzle 70 (internal passage of the discharge section 104, second passage 108, and light guide path 114).

[0071] Although preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to any particular embodiment, and various modifications are possible within the scope of the technical concept of the present invention. For example, in the above-described embodiment, the air supply path 90 and the light guide path 114 have a partially common configuration, but if the direction of the discharge section 104 can be appropriately set as described above, the air supply path 90 and the light guide path 114 may be formed separately in the air nozzle 70.

[0072] [Differentiation] Figure 12 is a schematic diagram showing the configuration of an air nozzle according to Modification 1. In this modified example, a light sensor 150 is installed in the light guide path 114 to detect the intensity of light incident from the exit 112. This detection information is output to the control unit 20 by wire or wireless connection. In the illustrated example, after the light sensor 150 is installed, the opening 118 is closed with a closing member 120. A small hole may be provided in the closing member 120 to allow the signal wire of the light sensor 150 to pass through. The control unit 20 acquires the detection information from the light sensor 150 and calculates the intensity of scattered light. Then, it displays information (numerical information, etc.) indicating the calculated light intensity on the display device 160. The light sensor 150 functions as a "detection unit," and the display device functions as an "output unit."

[0073] According to this modified example, the intensity of scattered light is calculated by the control unit 20, rather than by the user's visual inspection. This light intensity information is then provided to the user in a visually perceptible manner. The user can adjust the nozzle while referring to this light intensity information. Because it does not depend on the user's senses, it may be possible to adjust the nozzle more accurately. Note that if the light sensor 150 is embedded in the main body 102, it is not necessary to provide an opening for the light guide path 114.

[0074] Figure 13 is a flowchart showing the adjustment procedure for the air nozzle according to Modification Example 2. In this modified example, nozzle adjustment is performed in two stages: a first nozzle adjustment step and a second nozzle adjustment step. In the first nozzle adjustment step, the air nozzle 70 is roughly adjusted using a mirror wafer before dicing. In the second nozzle adjustment step, the air nozzle 70 is finely adjusted using a wafer after dicing.

[0075] First, the first nozzle adjustment step is performed. The control unit 20 controls the transport mechanism 12 to set the mirror wafer on the chuck table 34 before dicing (S210: first setting step). Then, it controls each movement mechanism to move the microscope 30 to the first adjustment position (S212: first movement step). The "first adjustment position" here refers to a position that is pre-set so that the focusing point P is located on the surface of the mirror wafer.

[0076] Next, the control unit 20 drives the microscope 30 and irradiates the surface of the mirror wafer with white light (S214: first irradiation step). A portion of the light reflected from the surface of the mirror wafer (scattered light) is incident on the ejection unit 104.

[0077] The user visually inspects the opening 118 of the air nozzle 70 and adjusts the position and orientation of the air nozzle 70 so that scattered light can be seen and the visible light is as bright as possible (S216: First adjustment step). Subsequently, the control unit 20 moves the microscope 30 to a predetermined standby position (S218).

[0078] Next, the second nozzle adjustment step is performed. The control unit 20 controls the transport mechanism 12 and sets the diced wafer in place of the mirror wafer on the chuck table 34 (S220: second setting step). Subsequently, alignment processing is performed using the microscope 28 (S221: alignment step). That is, the wafer is aligned to adjust the processing direction and the orientation of the processed line to match. Then, each moving mechanism is controlled to move the microscope 30 to the second adjustment position (S222: second moving step). The "second adjustment position" here is the position set so that the focusing point P is located on the bottom surface of the kerf formed on the wafer.

[0079] Next, the control unit 20 drives the microscope 30 and irradiates white light toward the bottom surface of the calf (S224: second irradiation step). At this time, a portion of the light reflected from the bottom surface of the calf (scattered light) is incident on the discharge unit 104.

[0080] The user visually inspects the opening 118 of the air nozzle 70 and adjusts the position and orientation of the air nozzle 70 so that scattered light is visible and the visible light is as bright as possible (S226: Second adjustment step).

[0081] According to this modified version, nozzle adjustment is performed in two stages—preliminary adjustment and fine adjustment—making the adjustment process easier for the user. This can reduce the number of adjustments required by the user and potentially improve adjustment efficiency.

[0082] Figure 14 is a flowchart showing the adjustment procedure for the air nozzle according to Modification Example 3. In this modified example, nozzle adjustment is also performed in two stages, but in the second nozzle adjustment step, the air nozzle 70 is finely adjusted according to the length of the water drainage time by air blowing. The first nozzle adjustment step (S210~S218) is the same as in Modified Example 2.

[0083] When the process moves to the second nozzle adjustment step, the control unit 20 controls the transport mechanism 12 to set the wafer with the water film attached after dicing onto the chuck table 34 in place of the mirror wafer (S230). Next, the wafer alignment process is performed using the microscope 28 (S231: alignment step). That is, the wafer is aligned to adjust the direction of processing and the direction of the processed line to match. Then, each movement mechanism is controlled to move the microscope 30 to the second adjustment position described above (S232).

[0084] Next, the control unit 20 drives the air supply unit 94 to perform an air blow (S234). At this time, the cutting fluid accumulated in the kerf is discharged. The user visually checks the progress of the cutting fluid removal and fine-tunes the position and orientation of the air nozzle 70 according to the progress (drainage time). That is, if the drainage time exceeds the standard time, fine adjustment is made. If the drainage time is within the standard time, no further fine adjustment is made.

[0085] [Other variations] In the above embodiment, an example was shown in which the chuck table 34 is configured to be movable in the X and θ directions, and the air nozzle is configured to be movable in the Y and Z directions. In a modified example, the chuck table 34 may be configured to be movable in the X, Y, and θ directions, and the air nozzle may be configured to be movable in the Z direction. Alternatively, the chuck table 34 may be configured to be movable only in the θ direction, and the air nozzle may be configured to be movable in the X, Y, and Z directions. Other configurations may be adopted as long as the chuck table 34 and the air nozzle can move relative to each other in the X, Y, Z, and θ directions.

[0086] In the above embodiment, the dicing apparatus 1 is exemplified as a blade dicing apparatus that performs cutting while pressing a blade against the wafer. Other dicing methods include laser dicing, which separates the surface of the wafer using laser light, plasma dicing, which divides the wafer into chips by dry etching using plasma, and other methods. Regardless of the method adopted, kerfs (grooves) are formed on the surface of the wafer by dicing, so the same nozzle adjustment method as in the above embodiment can be applied when measuring the shape of the grooves.

[0087] In the above embodiment, the nozzle adjustment method was applied to an air nozzle 70 assembled to a microscope 30 for shape measurement. In a modified example, the same nozzle adjustment method may be applied to an air nozzle assembled to an alignment microscope 28. The nozzle adjustment method can be applied to the relationship between a microscope used to observe grooves formed on a wafer by dicing and an air nozzle.

[0088] In the above embodiment, the use of the air nozzle 70 was exemplified as the removal of cutting fluid supplied during the dicing process. An example of nozzle adjustment to improve the efficiency of removing the cutting fluid was shown. This nozzle adjustment may be performed after the dicing process is completed, or it may be performed by temporarily pausing the cutting process during the dicing process.

[0089] When cleaning the wafer with cleaning water after dicing, the nozzle adjustments described above may be performed to improve the efficiency of removing the cleaning water. In other words, the nozzle adjustments may be performed not only in the processing area (processing section 14) of the dicing apparatus, but also in the cleaning area (cleaning section 16). The nozzle adjustments described above may also be performed for the purpose of removing water (cutting water, cooling water, cleaning water) adhering to the kerf formed by dicing.

[0090] Furthermore, the above-described nozzle adjustments can also be applied to the air nozzle used to remove foreign matter (chips, debris, dust, etc.) adhering to the kerf prior to microscopic observation of the kerf.

[0091] In the above embodiment, a simple mechanism for adjusting the nozzle was illustrated by the fitting structure of the air nozzle 70 body 102 and the support member 78 and the fastening of a screw 84 (see Figure 9), but it goes without saying that it is not limited to this. For example, a structure may be adopted that allows adjustment of at least one of the following: the angle in the θ direction of the air nozzle 70, the position in the XY direction, or the angle (tilt) with respect to the horizontal plane, depending on the amount of screws inserted into the nozzle.

[0092] Alternatively, a drive mechanism for driving the main body 102 in either direction may be provided at the tip of the lifting mechanism 76. When using the sensor shown in Figure 12, the control unit 20 may control the drive mechanism and automatically adjust the nozzle so that the light intensity detected by the light sensor 150 is maximized. The control unit 20 detects the intensity of the light guided to the light guide path 114 (light detection step), and when the detected light intensity becomes greater than a predetermined reference value, it terminates the adjustment of the position and orientation of the main body 102 (adjustment step).

[0093] In the above embodiment, a structure was illustrated in which light is guided to the opening 118 by a linear through-hole formed in the air nozzle 70 (internal passage of the discharge section 104, second passage 108, and light guide path 114). In a modified example, an optical mechanism (such as a mirror) may be placed in the through-hole connected to the outlet 112 of the discharge section 104 to guide light to the opening. This eliminates the need to form the through-hole in a linear shape.

[0094] In the above embodiment, a Mirau-type white light interferometer was exemplified as the microscope 30, but a Michelson-type or other type of white light interferometer may also be used.

[0095] It should be noted that the present invention is not limited to the embodiments and modifications described above, and the components can be modified and implemented without departing from the spirit of the invention. Various inventions may be formed by appropriately combining the multiple components disclosed in the embodiments and modifications described above. In addition, some components may be deleted from all the components shown in the embodiments and modifications described above. [Explanation of Symbols]

[0096] 1 Dicing device, 10 Load port, 12 Transfer mechanism, 14 Processing section, 16 Cleaning section, 20 Control unit, 24 Blade, 26 Workpiece holding section, 28 Microscope, 30 Microscope, 32 Spindle, 34 Chuck table, 36 Rotary table, 38 X table, 44 X movement mechanism, 46 Rotation mechanism, 54 Y table, 56 Y movement mechanism, 60 Z table, 62 Z movement mechanism, 70 Air nozzle, 72 Housing, 74 Lens unit, 76 Lifting mechanism, 78 Support member, 82 Air cylinder, 84 Screw, 86 Cover, 90 Air supply passage, 94 Air supply section, 98 Air supply source, 102 Main body, 104 Discharge section, 106 First passage, 108 Second passage, 110 Inlet, 112 Outlet, 114 Light guide path, 116 Connection section, 118 Opening, 120 Closure member, 124 objective lens, 128 reference mirror, 130 white light source, 132 imaging unit, 150 light sensor, AJ air jet, K kerf, L2 optical axis, P focusing point, S street, W wafer.

Claims

1. An air nozzle that discharges air, which is attached to a microscope for observing grooves formed in a wafer by dicing, A main body that is assembled to the microscope and has an air supply passage through which supplied air flows, A linear discharge section is provided on the outlet side of the air supply passage in the main body, The system includes an adjustment mechanism for adjusting the position and orientation of the main body relative to the microscope so that the direction of the discharge section is directed toward the focusing point of the microscope, The main body is an air nozzle having a light guide path that communicates with the air supply path and guides light incident from the outlet of the discharge section into the interior.

2. The main body further comprises a closing member, The light guide path has a connection portion to the air supply path at one end and an opening at the other end that opens to the outside of the main body, and guides the light incident from the outlet of the discharge section to the opening. The air nozzle according to claim 1, wherein the closing member is provided so as to be able to close the opening.

3. The aforementioned light guide path is a straight passage that communicates with the discharge section in the axial direction. The air nozzle according to claim 2, wherein the outlet of the discharge section and the opening of the light guide path are arranged in a straight line.

4. A detection unit for detecting the intensity of light guided to the aforementioned light guide path, An output unit that outputs light intensity information detected by the detection unit, The air nozzle according to claim 1, further comprising:

5. A shape measuring device for measuring the shape of grooves formed on a wafer by dicing, A microscope for measuring the shape of the groove, The microscope is equipped with an air nozzle that discharges air, The microscope includes a light source that emits light for measurement, and an objective lens positioned on the optical axis. The air nozzle includes a main body that is assembled to the microscope and has an air supply passage through which supplied air flows, a linear discharge section provided on the outlet side of the air supply passage in the main body, and an adjustment mechanism for adjusting the position and orientation of the main body relative to the microscope so that the direction of the discharge section is directed toward the focusing point of the microscope. The main body is a shape measuring device having a light guide path that communicates with the air supply path and guides light incident from the outlet of the discharge section into the interior.

6. The shape measuring device according to claim 5, wherein the light guide path has a connection portion to the air supply path at one end and an opening at the other end that opens toward the outside of the main body, and guides light incident from the outlet of the discharge portion to the opening.

7. A chuck table for holding wafers, A blade for dicing a wafer held on the chuck table, A cutting fluid supply unit that supplies cutting fluid to the blade in the dicing process, A microscope for observing grooves formed on a wafer by dicing, The microscope is equipped with an air nozzle that discharges air to remove cutting fluid adhering to the grooves during the dicing process, The microscope includes a light source that emits light for observation, and an objective lens positioned on the optical axis. The air nozzle includes a main body having an air supply path through which supplied air flows, a linear discharge section provided at the outlet end of the air supply path in the main body, and an adjustment mechanism for adjusting the position and orientation of the main body relative to the microscope so that the direction of the discharge section is directed toward the focusing point of the microscope. The main body is a dicing device having a light guide path that communicates with the air supply path and guides light incident from the outlet of the discharge section into the interior.

8. An apparatus comprising a microscope for observing grooves formed in a wafer by dicing, and an air nozzle attached to the microscope for discharging air to remove water adhering to the grooves, wherein the nozzle adjustment method is for adjusting the position and orientation of the air nozzle, The air nozzle includes an air supply path through which supplied air flows, a light guide path communicating with the air supply path, a main body assembled to the microscope, and a linear discharge section provided on the outlet side of the air supply path in the main body. The aforementioned light guide path guides the light incident from the outlet of the discharge unit. The nozzle adjustment method includes a moving step of moving the microscope so that the focal point is located in the groove of the wafer; an irradiation step of irradiating light from the microscope toward the groove of the wafer; and an adjustment step of adjusting the position and orientation of the main body relative to the microscope so that the direction of the ejection part is directed toward the focal point of the microscope. The adjustment step is a nozzle adjustment method that adjusts the position and orientation of the main body so that the intensity of the light guided into the light guide path by the reflection of the light from the microscope in the groove increases.

9. The light guide path has a connection portion to the air supply path at one end and an opening exposed to the outside at the other end, and guides the light incident from the outlet of the discharge section to the opening. The nozzle adjustment method according to claim 8, wherein the adjustment step involves adjusting the position and orientation of the main body so that the intensity of the light guided to the opening by the reflection of the light from the microscope in the groove increases.

10. A first nozzle adjustment step involves performing a preliminary adjustment of the air nozzle, This includes a second nozzle adjustment step for making fine adjustments to the air nozzle, The first nozzle adjustment step includes a first setting step of setting the mirror wafer before dicing; a first moving step of moving the microscope so that a focal point is located on the surface of the mirror wafer; a first irradiation step of irradiating light from the microscope toward the surface of the mirror wafer; and a first adjustment step of adjusting the position and orientation of the main body relative to the microscope so that the direction of the ejection unit is directed toward the focal point of the microscope. The nozzle adjustment method according to claim 9, wherein the second nozzle adjustment step includes a second setting step of setting a wafer after dicing; a second moving step of moving the microscope so that the focal point is located in the groove of the wafer; a second irradiation step of irradiating light from the microscope toward the groove of the wafer; and a second adjustment step of adjusting the position and orientation of the main body relative to the microscope so that the direction of the ejection part is directed toward the focal point of the microscope.

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