Method and apparatus for monitoring the tension of a cutting tape

Abstract

Method and apparatus for monitoring the tension of a cutting belt. A method for monitoring the tension of a cutting belt is described. The method includes obtaining tension data indicative of the tension of each cutting belt by means of an automatic optical inspection of each cutting belt.

Description

Technical Field

[0001] The present disclosure relates to the field of wafer handling, and in particular to quality monitoring and production data documentation during wafer handling. Background Art

[0002] Many processes in wafer manufacturing are automated to provide a high degree of process reliability and maximize throughput. Thus, product and process control techniques are widely used, and quality issues or throughput reductions can be traced to specific products or process conditions for improvement.

[0003] A specific process in wafer handling refers to the step of mounting a wafer on a dicing tape. Mounting the wafer on the dicing tape is typically done by an automatic wafer mounter that adjusts the dicing tape and places the wafer on the adjusted dicing tape. Adjustment of the dicing tape particularly involves providing a dicing tape tension that is suitable for subsequent wafer processing such as dicing. Summary of the Invention

[0004] According to a first aspect, a method of monitoring dicing tape tension includes: obtaining tension data indicative of the dicing tape tension by automatic optical inspection of each dicing tape.

[0005] According to a further aspect, an apparatus for monitoring dicing tape tension includes means for obtaining tension data indicative of the dicing tape tension by automatic optical inspection of each dicing tape.

[0006] According to another aspect, a computer program product includes instructions that cause an apparatus for monitoring dicing tape tension to obtain tension data indicative of the dicing tape tension by automatic optical inspection of each dicing tape and store the tension data for a specific dicing tape in a database. The database is configured to link the tension data to a wafer identifier of a wafer diced on the specific dicing tape.

[0007] According to yet another aspect, a computer program product includes instructions that cause a data processing device for evaluating the tension data to derive a dicing tape tension quality measurement for each dicing tape and update parameters that control the dicing tape tension of a dicing tape actually laminated on a frame based on dicing tape tension quality measurements of one or more previous dicing tapes, and / or stop the process of mounting a wafer on a dicing tape based on dicing tape tension quality measurements of one or more previous dicing tapes. Brief Description of the Drawings

[0008] Figure 1 is a schematic diagram of an exemplary wafer mounter.

[0009] Figure 2 Schematic diagram of an exemplary device for monitoring the tension of a cutting tape.

[0010] Figure 3 Cross-sectional view and plan view showing an example of a cutting tape laminated on a frame.

[0011] Figure 4 Block diagram schematically showing an exemplary device for monitoring the tension of a cutting tape and / or a computer program product adapted to execute instructions to operate the device and / or adapted to be executed on the device.

[0012] Figures 5A-5B Flowchart of an exemplary process of a method for monitoring the tension of a cutting tape. Detailed Description

[0013] It should be understood that the features of the various exemplary embodiments and examples described herein can be combined with each other unless otherwise specifically indicated.

[0014] Wafer dicing is a process for singulating semiconductor wafers into die, which are also referred to as chips. To this end, the front-end processed wafer is placed on a cutting tape, which serves as a mounting tool during the cutting process.

[0015] In fact, placing the wafer on the corresponding cutting tape is a fully automated process performed by a wafer processing device, which is also referred to as a wafer bonder in the art. Figure 1 Schematically illustrates an example of a wafer bonder 100. Briefly, the front-end preprocessed wafer is loaded into the wafer bonder 100 at a load station 110. The robotic arm 120 transfers the individual wafer to an alignment tool 130.

[0016] At the same time, the cutting tape is cut and laminated on a frame. Generally, the frame is an annular frame, and the cutting can be performed by punching out the cutting tape from a cutting tape reel that is rewound to a roll. The cutting and lamination of the cutting tape can be performed at a cutting tape cutting and lamination station 140.

[0017] As will be explained in further detail below, the dicing tape needs to have a specific tension when suspended on the frame. If the dicing tape tension is outside a specific range or tension window, several problems may occur during subsequent wafer processing. In particular, if the tape tension is too high, the distance between adjacent die may be too small after wafer dicing (e.g., so-called die knocking may occur). In addition, during subsequent processes, especially during ringcut dicing or taiko ring removal processes, inappropriate tape tension may cause hairline cracks.

[0018] The tape tension on the frame can be controlled during the process of bonding (e.g., laminating) the dicing tape to the frame. For example, a continuous dicing tape is punched out from a dicing tape reel, and the dicing tape reel is laminated onto the frame in the Y direction. The tension in the Y direction can be controlled by the lamination process, e.g., by the tensile force applied to the dicing tape (reel) during lamination or by the parameters of the lamination roller. For example, the tension in the X direction (which is perpendicular to the Y direction) can be controlled by applying a predetermined deformation to the ring frame during the lamination process. That is, before laminating the dicing tape onto the frame, the frame can be compressed a specific distance in the X direction, so as to apply a predetermined and reproducible expansion force to the dicing tape after lamination and frame release.

[0019] In practice, the dicing tape tension is a quantity that only shows slow changes during the automatic dicing tape application process at the dicing tape cutting and laminating station 140. Conventionally, during the operation of the wafer bonder 100, it is considered sufficient to check the tape tension on the frame only once or a few times a week. In addition, since the tape tension depends on the characteristics of the dicing tape (e.g., manufacturer, type of dicing tape, physical properties of the dicing tape, etc.), it may be necessary to readjust the tape tension when the dicing tape reel is changed (e.g., when using a reel from another manufacturer).

[0020] Still referring to Figure 1 , after the dicing tape is attached to the frame at the dicing tape cutting and laminating station 140, the dicing tape laminated on the frame can be transferred to the wafer bonding station 160. At the wafer bonding station 160, the wafer is placed on the pre-stretched dicing tape.

[0021] The dicing tape supported by the frame carrying the wafer can be transferred back to the transfer arm 150 and moved to the device 200 for monitoring the dicing tape tension.

[0022] The apparatus 200 for monitoring the tension of a dicing tape includes means for obtaining tension data indicative of the tension of the dicing tape by automatic optical inspection of each dicing tape. The apparatus 200 for monitoring the tension of the dicing tape may be configured to obtain the tension data for each dicing tape, i.e., for each wafer processed by the wafer mounter 100. Exemplary features and techniques applied by the apparatus 200 for monitoring the tension of the dicing tape will be explained in further detail below.

[0023] Downstream of the apparatus 200 for monitoring the tension of the dicing tape, the wafer may be transferred to a wafer labeling station 170 for attaching a wafer ID (identifier) label to the wafer. For example, the wafer ID label may be a barcode label or any other identifier suitable for individualizing and tracking the wafer and / or the chips diced from the wafer during subsequent processing, including, for example, packaging, assembly, and / or shipping to a customer.

[0024] A further stage of wafer processing in the wafer mounter 100 may involve a delivery tool 180 configured to deliver the wafer mounted on the frame dicing tape to a frame cassette and unload the frame cassette at an output station 190.

[0025] The processes and stations of the wafer mounter 100 as described above are exemplary and, within the scope of the present disclosure, may be replaced by other processes or stations or may be omitted (except for the wafer mounting station 160). In particular, the apparatus 200 for monitoring the tension of the dicing tape may also be implemented as a station external to the wafer mounter 100, for example, may be arranged downstream of the output station 190 of the wafer mounter 100.

[0026] Figure 2 An exemplary apparatus 200 for monitoring the tension of a dicing tape (or more specifically, the hardware of such an apparatus) is shown. The apparatus 200 for monitoring the tension of the dicing tape includes means for obtaining tension data indicative of the tension of the dicing tape by automatic optical inspection of each dicing tape.

[0027] The apparatus 200 for monitoring the tension of the dicing tape may include a light source 202 for back (bottom) illumination of the dicing tape 220 and / or the frame 210 on which the dicing tape 220 is mounted (e.g., laminated). More specifically, the frame 210 (e.g., an annular frame 210 having a diameter of, for example, 12 inches) is positioned at a defined position above the bottom of the apparatus 200 for monitoring the tension of the dicing tape. A wafer (not shown, e.g., hidden by the edge of the frame 210) may be placed, for example, on top of the dicing tape 220.

[0028] One option is that the light source 202 illuminates the entire surface of the cutting tape 220 and / or the frame 210 to provide reflected light from all areas within the contour of the frame 210. Another possibility is to provide illumination of specific areas or zones only at the bottom side of the frame 210 and / or the cutting tape 220, for example, at the edge of the frame 210 or at a predetermined tape area.

[0029] The light source 202 can emit RGB (red, green, blue) light for different cutting tapes 220. For example, the light source 202 can use RGB LEDs (light emitting diodes). The light source 202 can be designed as a ring light source (not shown) to allow reflected light from the entire surface of the cutting tape 220 and / or the frame 210 to pass through the opening of the ring light source 202. It is also possible to design the light source 202 to provide scanning illumination.

[0030] The device 200 for monitoring the cutting tape tension can further include a camera 204 for acquiring a complete image or at least a partial image of the frame 210 and / or the cutting tape 220. A mirror 206 can be provided in the optical path between the frame 210 and / or the cutting tape 220 and the camera 204 to account for the limited mounting height H of the device 200 for monitoring the cutting tape tension (e.g., the height H can be equal to or less than 390 mm to retrofit the device 200 for monitoring the cutting tape tension into a conventional wafer bonder 100).

[0031] Figure 3 A cross-sectional view ( Figure 3 upper part) of the frame 210 and the cutting tape 220 laminated thereon and a plan bottom view ( Figure 3 lower part) are shown. Figure 3 Specific examples of how to measure the tape expansion in the X direction and the Y direction are further shown. Then, the tape expansion data in the X direction and the Y direction can be translated in the tape tension data by an appropriate data processing device for calculating the tape tension data.

[0032] Automated image analysis for measuring a quantity indicative of the length dimension of the cutting tape 220 (e.g., in the X direction and / or in the Y direction) can include detecting visual features of the cutting tape 220. In Figure 3 , the visual feature of the cutting tape 220 in the X direction is, for example, the edge 222 of the cutting tape 220, such as the right edge 222 and / or the left edge 222 of the cutting tape 220.

[0033] In addition, automated image analysis can, for example, include detecting visual features of the frame 210. In Figure 3Among them, for example, the visual feature of the frame 210 can be the frame edge 212, such as the frame edge 212 on the left side of the frame 210 and the frame edge 212 on the right side of the frame 210.

[0034] Then, the distance Δx1 between the visual feature of the cutting strip 220 and the visual feature of the frame 210 at the left side of the frame 210 can be measured by automatic image analysis, and / or the distance Δx2 between the visual feature of the cutting strip 220 and the visual feature of the frame 210 at the right side of the frame 210 can be measured by automatic image analysis.

[0035] Since the size of the frame 210 in the X direction is precisely known, the measured values Δx1 and / or Δx2 allow the precise calculation of the belt extension in the X direction. In addition, since the belt extension in the X direction before laminating the belt 220 onto the frame 210 is precisely known (for example, corresponding to the size of the punch for generating the cutting strip disk), the measured values Δx1 and Δx2 indicate the belt expansion in the X direction.

[0036] Similar measurements of Δy1 and Δy2 can be performed in the Y direction to calculate the belt extension in the Y direction. From the belt extension in the Y direction, the belt expansion and belt tension values in the Y direction can be derived, as explained above with reference to the analysis of the measured values of Δx1 and Δx2.

[0037] It is not mandatory to use the visual feature of the frame 210 (here, for example, the frame edge 212) as the reference line for measuring the extension of the cutting strip 220. Instead, it is also possible to measure the extension of the cutting strip 200 only using the visual feature of the cutting strip 220 (for example, the opposite cutting strip edges 222), and derive the cutting strip 220 expansion from the knowledge of the cutting strip 220 extension before lamination. However, the measurement based on the visual feature of the frame 210 as a reference especially provides the possibility of collecting additional information, for example, allowing the tracking of the possible drift of the position of the cutting strip 220 on the frame 210 over time.

[0038] Exemplary measurements as outlined above (with or without reference to any reference at frame 210) provide global (i.e., non-local) average tension data for the cutting tape 220 in the X direction and / or the Y direction. There are many variations by which such data can be obtained. For example, it is possible to use line patterns or other markings in the X direction and / or the Y direction on the cutting tape 220 as visual features instead of the edge 222 of the cutting tape 220. If one or more line patterns or markings are applied to the cutting tape 220, this also allows local tension data to be obtained, since the non-uniformity of the distance between the lines of the pattern at different regions of the cutting tape 220 can be measured and evaluated. In other words, automated image analysis can be designed to measure any quantity indicative of the length dimension of the cutting tape 220 to derive non-local or local tape tension data in the X and / or Y direction.

[0039] In addition, the tension distribution of the cutting tape 220 can be measured by other means than length measurement, for example by photoelasticity measurement. As is known in the art, photoelasticity describes the change in the optical properties of a material (here: the cutting tape 220) under mechanical deformation. Photoelasticity measurements can determine the tension distribution in the cutting tape 220, i.e., can provide tension data reflecting the local tension distribution across the cutting tape 220.

[0040] It should be noted that the acquisition of tension data via distance measurement and the acquisition of tension data via photoelasticity measurement can be combined. Such a combination can provide monitoring of the tension of the cutting tape 220 by combining the collection of accurate average tension data and tension distribution data.

[0041] Figure 4 A block diagram of an exemplary device 200 for monitoring the tension of a cutting tape is shown. The monitoring device 200 includes an optical sensor 410 that is configured to acquire tension data indicative of the cutting tape tension by automated optical inspection of each cutting tape 220. The optical sensor 410 can be designed in accordance with the features and processes described in conjunction with Figures 1-3 In particular, the optical sensor 410 can include the hardware of the device 200 as shown in Figure 2 , such as a light source 202 for illuminating the cutting tape 220 with light and a camera 204 for acquiring at least a partial image of the cutting tape 220.

[0042] The optical sensor 410 can output image data Idat at output 412. The image data Idat can be transmitted to a computing environment 400 that includes an image analyzer 420, an (optional) data processor 430, and an (optional) controller 440.

[0043] The image analyzer 420 can be designed to analyze the image data Idat for detecting, for example, visual features and / or photoelastic properties, and can measure quantities indicative of the length dimension of the cutting band 220 and / or, for example, the tension distribution of the cutting band 220 as explained with reference to Figure 3 a quantity. The image analyzer 420 can be configured to derive tension data Tdat indicative of the tension of the cutting band 220 from the measured quantities. The tension data Tdat can be local tension data or non-local, such as the average (mean) tension data as described above.

[0044] Computer-based or computer-aided image analysis methods and tools, such as computer programs, can be used to analyze the image data Idat. The image analysis method can, for example, include image segmentation and / or identification of visual features such as frames or band edges or line patterns. Image segmentation can include thresholding, i.e., generating a black-and-white image (or grayscale value image) based on comparing the values of the image voxels (e.g., brightness values) with a threshold (e.g., brightness threshold) or with multiple thresholds (e.g., multiple brightness thresholds). The segmented image can be analyzed for visual feature identification. In addition, the image data (e.g., the segmented image) can be analyzed for identification of objects other than the visual features for tension data generation, for example, for identification and (optionally) classification of scratches, particles, etc. at the cutting band 220 or at the bottom side of the wafer.

[0045] The tension data Tdat from the image analyzer 420 can be passed to the data processor 430. The data processor 430 can evaluate the tension data to derive a cutting band tension quality measurement for each cutting band. The cutting band tension quality measurement can be derived based on whether the tension data Tdat is within a specific range. More specifically, the data processor 430 can compare the tension data Tdat in the X direction with a specific tension data window (or range) for the X direction, and can compare the tension data Tdat in the Y direction with a specific tension data window (or range) for the Y direction.

[0046] If both windows (ranges) are satisfied, the data processor 430 can, for example, output a tension quality measurement Tqual, which indicates that the cutting band tension is within a specified quality (e.g., "good quality"). If one or both of the tension data Tdat in the X direction and the Y direction are outside the boundaries of the corresponding window (range), the data processor 430 can output a low or insufficient cutting band tension quality (e.g., Tqual is "low quality" or "insufficient quality").

[0047] The tape tension quality measurement Tqual output by the data processor 430 may include various information about the tape tension of each tape 220. For example, the tape tension quality measurement Tqual may include a quality measurement indicating the drift of the tension data Tdat over time (e.g., continuously increasing or continuously decreasing), or a quality measurement indicating any approach of the tension data Tdat to the boundary of the tension data window (range). Such or other quality measurements Tqual can allow for the early identification of unwanted or critical process developments during the operation of the wafer mounter 100.

[0048] Optionally, the tape tension quality measurement Tqual derived by the data processor 430 can be transmitted to the controller 440. The controller 440 can be configured to update the parameter P that controls the tape tension of the tape actually laminated on the frame 210 based on the tape tension quality measurements Tqual of one or more previous tapes. For example, if the controller 440 is notified of a low tape tension quality in the X direction (based on finding that the tape tension in the X direction is close to the lower boundary of the tape window), then the controller 440 can output a parameter indicating that the tool in the wafer mounter 100 increases the pre-compression of the frame 210 in the X direction. Similarly, if it is evaluated that the tape tension in the Y direction is close to the lower boundary of the tape window in the Y direction, the tautness of the tape during the lamination process can be increased.

[0049] As another example, the controller 440 can output a stop signal S. The stop signal S can stop the process of mounting the wafer on the tape, i.e., it can stop the operation of the wafer mounter 100. The issuance of the stop signal S can be based on the tape tension quality measurements Tqual of one or more previous tapes. As an example, if the tape tension quality measurement Tqual indicates that the actual tape tension is outside the range (i.e., beyond the boundary of the tape window), then the stop signal S can be set to abort the manufacturing process in order to prevent mounting the wafer on a tape with a critical tape tension.

[0050] Generally, the (optional) controller 440 provides feedback functionality that allows information derived from the evaluation of the measured tape tension to be fed back to the manufacturing process. Based on this information, the manufacturing process can be adjusted or stopped.

[0051] The apparatus 200 for monitoring the tension of the cutting tape may also include or be coupled to a data storage device 450. The data storage device 450 may store the tension data Tdat (from the image analyzer 420) of each cutting tape by using a database DB, where the database DB is configured to link the tension data Tdat to the wafer identifier of the specific wafer mounted on the specific cutting tape (e.g., as applied at the wafer labeling station 170). In this way, information about the individual cutting tape tensions associated with each wafer can be obtained by accessing the database DB.

[0052] In addition, as Figure 4 shown, the information output by the data processor 430 (i.e., the cutting tape tension quality measurement Tqual) and / or process control information (process control parameters P and / or stop signal S) may optionally be stored in the data storage device 450.

[0053] The information stored in the data storage device 450 allows for the precise documentation and traceability of the manufacturing process on a wafer-by-wafer basis. In this context, database technologies (including decentralized blockchain database technologies) may be used. In particular, data storage and evaluation allow for a better understanding of the relationship between cutting tape tension and production yield issues. In addition, data storage in combination with database technologies (including, for example, blockchain database technologies) allows defective products (e.g., chips, chip packages, assembly devices, etc.) reported or returned by customers to be associated with the tension data Tdat and / or quality measurement Tqual and / or process control information (e.g., P, S) of the specific cutting tape on which the corresponding wafer was mounted and cut during the production process.

[0054] In other words, the methods and apparatus described herein allow for early manufacturing process intervention and process adjustment and / or traceability issue identification and traceability improvement of the manufacturing process to prevent the identified issues in the future.

[0055] In addition, the data stored in the data storage device 450 may be analyzed according to different cutting tape manufacturers, different cutting tape types, different cutting tape batches, different cutting tape physical properties such as tape viscosity and / or tape thickness, different cutting tape adhesives, etc. Based on this analysis, the optimal settings of the parameters for controlling the cutting tape tension during the lamination process can be derived. This can greatly facilitate the resetting of these parameters when changing the cutting tape roll (e.g., if using a cutting tape roll from another manufacturer or having other physical properties or other adhesives, etc.). As a result, the manufacturing process can be stabilized, the yield can be improved, and the downtime of the wafer loader 100 for maintaining and / or changing the cutting tape roll can be reduced.

[0056] Figure 5AAn exemplary method of monitoring the tension of a dicing tape is shown. At S1, tension data indicating the tension of each dicing tape is obtained by automated optical inspection of each dicing tape. Many examples of how to obtain the tension data are described above.

[0057] At S2, the tension data of a specific dicing tape is stored in a database, where the database is configured to link the tension data to the wafer identifier of the wafer to be diced on the specific dicing tape. In this way, individual wafer tension data is available.

[0058] Referring Figure 5B , Figure 5A the method of

[0059] still referring Figure 5B and the method alone (for processing the tension data already obtained and starting from S3) may include evaluating the tension data at S3 to derive a dicing tape tension quality measurement for each dicing tape. This may involve comparing the tension data with a predetermined tension threshold at S3_1, where the threshold may be, for example, the boundary of a predetermined dicing tape tension window (or range), and setting the dicing tape quality measurement Tqual based on the comparison at S3_2.

[0060] The disclosure herein also supports one or more computer program products, the one or more computer program products including computer-executable code or computer-executable instructions that, when executed, cause at least one computer to perform one or more of the methods described herein, particularly the methods described with respect to Figure 3 , 4 5A and 5B. One or more such computer program products may include a readable storage medium having program code stored thereon for use by a processor, the program code including instructions for performing any of the methods described above.

[0061] More specifically, the first computer program product may include instructions to cause a device for monitoring the cutting tape tension to store tension data in the data storage device 450 at S2. The first computer program product may further include instructions for deriving the tension data. The tension data may be derived by automatic image analysis to measure quantities indicative of the length dimension of the cutting tape and / or the stress distribution of the cutting tape. Thus, the first computer program product may control the operation of the data storage device (e.g., database) 450 and / or may control the operation of the image analyzer 420 that generates the tension data stored in the data storage device (e.g., database) 450.

[0062] In addition, the second computer program product may include instructions to cause the data processor 430 to execute process S3, e.g., S3_1, e.g., S3_2, and / or to cause the controller 440 to execute processes S4_1 and / or S4_2. The second computer program product may thus operate the data processor 430 to calculate the cutting tape tension quality measurement Tqual and / or the controller 440 to perform manufacturing process control tasks.

[0063] If the cutting tape tension quality measurement Tqual and / or parameter P and / or stop signal S are to be stored in the data storage device 450, the second computer program product may also interface with the data storage device (e.g., database) 450.

[0064] That is, the computing environment 400 including the image analyzer 420 and, e.g., the data processor 430 and, e.g., the controller 440 may be implemented in software, implemented in hardware, or implemented partly in software and partly in hardware. Further, the computing environment 400 (e.g., a computer running the (one or more) computer program products) may be interfaced to the sensor 410 via a LAN (local area network) and / or may be interfaced to the data storage device (e.g., database) 450 via a LAN or a global transmission network such as, e.g., the Internet. The computing environment 400 may be part of a spatially distributed computing system or network having CPU cores (e.g., processors) deployed at different locations.

[0065] The following examples relate to further aspects of the present disclosure:

[0066] Example 1 is a method for monitoring the cutting tape tension, the method including obtaining tension data indicative of the cutting tape tension by automatic optical inspection of each cutting tape.

[0067] In Example 2, the subject matter of Example 1 may optionally include storing the tension data of a specific cutting tape in a database configured to link the tension data to a wafer identifier of a wafer cut on the specific cutting tape.

[0068] In Example 3, the subject matter of Example 1 or 2 may optionally include: wherein obtaining the tension data includes illuminating the cutting tape with light; obtaining at least a partial image of the cutting tape; and performing an automatic image analysis to measure a quantity indicative of the length dimension of the cutting tape and / or the tension distribution of the cutting tape.

[0069] In Example 4, the subject matter of Example 3 may optionally include: wherein performing an automatic image analysis to measure a quantity indicative of the length dimension of the cutting tape includes detecting visual features of the cutting tape; detecting visual features of a frame on which the cutting tape is laminated; and measuring the distance between the visual features of the cutting tape and the visual features of the frame.

[0070] In Example 5, the subject matter of Example 3 or 4 may optionally include: wherein performing an automatic image analysis to measure a quantity indicative of the length dimension of the cutting tape includes detecting a first visual feature of the cutting tape; detecting a second visual feature of the cutting tape; and measuring the distance between the first visual feature and the second visual feature of the cutting tape.

[0071] In Example 6, the subject matter of any of the foregoing examples may optionally include evaluating the tension data to derive a cutting tape tension quality measurement for each cutting tape.

[0072] In Example 7, the subject matter of Example 6 may optionally include: wherein evaluating the tension data includes comparing the tension data with a predetermined tension threshold; and setting the cutting tape tension quality measurement based on the comparison.

[0073] In Example 8, the subject matter of Example 6 or 7 may optionally include updating parameters controlling the cutting tape tension of a cutting tape actually laminated on a frame based on the cutting tape tension quality measurements of one or more previous cutting tapes, and / or stopping the process of mounting a wafer on a cutting tape based on the cutting tape tension quality measurements of one or more previous cutting tapes.

[0074] Example 9 is an apparatus for monitoring cutting tape tension, the apparatus including means for obtaining tension data indicative of cutting tape tension by automatic optical inspection of each cutting tape.

[0075] In Example 10, the subject matter of Example 9 may optionally include: wherein the means for obtaining the tension data includes a light source for illuminating the cutting tape with light; a camera for obtaining at least a partial image of the cutting tape; and an automatic image analyzer for measuring a quantity indicative of the length dimension of the cutting tape and / or the tension distribution of the cutting tape.

[0076] In Example 11, the subject matter of Example 9 or 10 may optionally include data storage means for storing the tension data of a specific cutting tape in a database configured to link the tension data to a wafer identifier of a wafer cut on the specific cutting tape.

[0077] In Example 12, the subject matter of any one of Examples 9 to 11 may optionally include a data processing device configured to evaluate tension data to derive a cut tape tension quality measurement for each cut tape.

[0078] In Example 13, the subject matter of Example 11 or 12 may optionally include, wherein the data processing device is further configured to update parameters controlling the cut tape tension of the cut tape actually laminated on the frame based on the cut tape tension quality measurements of one or more previous cut tapes, and / or stop the process of mounting the wafer on the cut tape based on the cut tape tension quality measurements of one or more previous cut tapes.

[0079] Example 14 is a computer program product comprising instructions for causing the apparatus of Example 11 to perform the steps of the method of Example 2.

[0080] Example 15 is a computer program product comprising instructions for causing the apparatus of Example 12 to perform the steps of the method of Example 8.

[0081] In Example 16, the subject matter of Example 8 may optionally include: wherein the parameter is the bias deflection of the frame on which the cut tape is laminated and / or the lamination parameter controlling the tension of the cut tape when laminated onto the frame.

[0082] In Example 17, the subject matter of Example 7 may optionally include: wherein the predetermined tension threshold depends on one or more of the viscosity, type, manufacturer, thickness, and adhesive material of the cut tape.

[0083] Example 18 is a wafer mounter comprising an apparatus for monitoring cut tape tension according to any one of Examples 9 to 13.

[0084] In Example 19, the subject matter of Example 9 may optionally include means for illuminating the cut tape with light; and means for acquiring at least a partial image of the cut tape.

[0085] In Example 20, the subject matter of Example 9 may optionally include means for performing an automatic image analysis to measure a quantity indicative of the length dimension of the cut tape and / or the tension distribution of the cut tape.

[0086] In Example 21, the subject matter of Example 20 may optionally include: the means for performing an automatic image analysis to measure a quantity indicative of the length dimension of the cut tape includes means for detecting visual features of the cut tape; means for detecting visual features of the frame on which the cut tape is laminated; and means for measuring the distance between the visual features of the cut tape and the visual features of the frame.

[0087] In Example 22, the subject matter of Example 20 or 21 may optionally include: an apparatus for performing automated image analysis to measure a quantity indicative of the length dimension of a cutting tape, the apparatus including an apparatus for detecting a first visual feature of the cutting tape; an apparatus for detecting a second visual feature of the cutting tape; and an apparatus for measuring a distance between the first visual feature of the cutting tape and the second visual feature of the cutting tape.

[0088] In Example 23, the subject matter of Example 9 and any one of Examples 20 to 22 may optionally include an apparatus for evaluating tension data to derive a cutting tape tension quality measurement for each cutting tape.

[0089] In Example 24, the subject matter of Example 23 may optionally include: an apparatus for evaluating tension data, the apparatus including an apparatus for comparing the tension data with a predetermined tension threshold; and an apparatus for setting the cutting tape tension quality measurement based on the comparison.

[0090] In Example 25, the subject matter of Example 23 or 24 may optionally include an apparatus for updating parameters that control the cutting tape tension of a cutting tape actually laminated on a frame based on cutting tape tension quality measurements of one or more previous cutting tapes, and / or an apparatus for stopping the process of mounting a wafer on a cutting tape based on cutting tape tension quality measurements of one or more previous cutting tapes.

[0091] Although the invention has been described with reference to illustrative embodiments, the description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the specification. Accordingly, the appended claims are intended to cover any such modifications or embodiments.

Claims

1. A method for monitoring the tension of a dicing tape, the dicing tape being used as a wafer mounting tool during the wafer dicing process, the method comprising: Obtaining tension data indicative of the tension of the dicing tape through automatic optical inspection of each dicing tape; And Storing the tension data of a specific dicing tape in a database configured to link the tension data to a wafer identifier of a wafer diced on the specific dicing tape.

2. The method according to claim 1, wherein, Obtaining the tension data includes: Illuminating the dicing tape with light; Obtaining at least a partial image of the dicing tape; and Performing automatic image analysis to measure a quantity indicative of the length dimension of the dicing tape and / or the tension distribution of the dicing tape.

3. The method according to claim 2, wherein, Performing automatic image analysis to measure a quantity indicative of the length dimension of the dicing tape includes: Detecting visual features of the dicing tape; Detecting visual features of the frame of the laminated dicing tape thereon; and Measuring the distance between the visual features of the dicing tape and the visual features of the frame.

4. The method according to claim 2 or 3, wherein, Performing automatic image analysis to measure a quantity indicative of the length dimension of the dicing tape includes: Detecting a first visual feature of the dicing tape; Detecting a second visual feature of the dicing tape; and Measuring the distance between the first visual feature of the dicing tape and the second visual feature of the dicing tape.

5. The method according to one of the preceding claims, further comprising: Evaluating the tension data to derive a dicing tape tension quality measurement for each dicing tape.

6. The method according to claim 5, wherein, Evaluating the tension data includes: Comparing the tension data with a predetermined tension threshold; and Setting the dicing tape tension quality measurement based on the comparison.

7. The method according to claim 5 or 6, further comprising: Updating parameters controlling the dicing tape tension of the dicing tape actually laminated on the frame based on the dicing tape tension quality measurements of one or more previous dicing tapes, and / or Stopping the process of mounting the wafer on the dicing tape based on the dicing tape tension quality measurements of one or more previous dicing tapes.

8. An apparatus for monitoring the tension of a dicing tape, the dicing tape being used as a wafer mounting tool during the wafer dicing process, the apparatus comprising: Means for obtaining tension data indicative of the tension of the dicing tape through automatic optical inspection of each dicing tape; And Data storage means for storing the tension data of a specific dicing tape in a database configured to link the tension data to a wafer identifier of a wafer diced on the specific dicing tape.

9. The device according to claim 8, wherein, The means for obtaining the tension data includes: A light source for illuminating the dicing tape with light; A camera for obtaining at least a partial image of the dicing tape; and An automatic image analyzer for measuring a quantity indicative of the length dimension of the dicing tape and / or the tension distribution of the dicing tape.

10. The apparatus according to claim 8 or 9, further comprising: Data processing means for evaluating the tension data to derive a dicing tape tension quality measurement for each dicing tape.

11. The device according to claim 10, wherein, The data processing means is further configured to update parameters controlling the dicing tape tension of the dicing tape actually laminated on the frame based on the dicing tape tension quality measurements of one or more previous dicing tapes, and / or Stop the process of mounting the wafer on the dicing tape based on the dicing tape tension quality measurements of one or more previous dicing tapes.

12. A computer program product comprising instructions for causing the apparatus of claim 8 to perform the steps of the method of claim 1.

13. A computer program product comprising instructions for causing the apparatus of claim 10 to perform the steps of the method of claim 7.

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