JP6625857B2 - Wafer processing method - Google Patents

Description

  The present invention relates to a wafer processing method for circulating a wafer between wafer processing apparatuses and processing the wafer in each wafer processing apparatus.

  When performing a series of processing such as a cutting process or a grinding process on a semiconductor wafer, a plurality of (for example, 25) wafers are housed in a cassette, and the wafers are transported in cassette units (for example, see Patent Document 1). 1). In the grinding apparatus, a plurality of wafers each having a protective tape adhered to the surface are housed in a cassette, and the wafers taken out of the cassette are housed in another cassette after being ground. On the other hand, in the cutting device, a plurality of wafers are accommodated in a cassette while being supported by an annular frame via a dicing tape, and the wafer taken out of the cassette is returned to the original cassette after being cut.

JP-A-09-027543

  In the system described in Patent Literature 1, wafers are taken out one by one from a cassette containing a plurality of wafers and processed by a grinding device or a cutting device. For this reason, even if the next stage is in a standby state in which the next cassette can be loaded, if all the wafers in the cassette have not been processed in the previous stage, useless standby time occurs. And it is inefficient. This problem is difficult to avoid even if the transport of the cassette is automated between processes.

  The present invention has been made in view of such a point, and an object of the present invention is to provide a wafer processing method capable of reducing unnecessary standby time of a wafer processing apparatus.

In the wafer processing method of the present invention, a transfer mechanism is provided between a plurality of wafer processing apparatuses configured to support a wafer at an opening of an annular frame via an adhesive tape and to perform processing on a wafer of a wafer unit to which a wafer ID is assigned. A wafer processing method for performing a series of processing by transferring wafers one by one, wherein the transfer mechanism includes a conveyor as an annular circulating transfer path installed along a plurality of wafer processing apparatuses; And a plurality of storage trays that are stored for each sheet and placed on the conveyor and circulated and conveyed, wherein the plurality of wafer processing apparatuses store one wafer on the plurality of storage trays on the conveyor. A loading device for loading each wafer, a processing device for receiving and processing wafers from the plurality of storage trays on the conveyor, and a processed wafer processed by the processing device Each of the wafer processing apparatuses detects a storage tray or a wafer ID capable of loading and unloading wafers from the plurality of storage trays circulated and transported on the conveyor. Detecting means, and a transfer means for transferring wafers between the plurality of storage trays circulated and transported on the conveyor and each of the wafer processing apparatuses, wherein the detecting means of the loading apparatus is circulated and transported. Detecting a vacant storage tray that can be loaded from the plurality of storage trays, and transferring the wafer to the empty storage tray on the conveyor by the transfer unit of the loading device; The detecting means of the apparatus detects a wafer ID of a wafer to be processed from among the plurality of circulating storage trays, and the transfer means of the processing apparatus A wafer processing step of receiving the wafer to be processed from the storage tray and processing the wafer; and, after performing the wafer processing step, the detection means of the processing apparatus includes a plurality of the detection trays circulated and conveyed. Detecting a vacant storage tray that can be carried in from the apparatus, and receiving the processed wafer to the empty storage tray by the receiving means of the processing apparatus; and Detecting the processed wafer to be processed, the delivery means of the unloading device receives the processed wafer from the storage tray, and a wafer unloading step of unloading the processed wafer from the conveyor , comprising: At least one of them is a processed wafer storage tray capable of storing only processed wafers. I do .

  According to this configuration, a plurality of wafer processing apparatuses including a loading apparatus, a processing apparatus, and an unloading apparatus are connected by the circulating transport path of the conveyor. In addition to the empty storage tray, a storage tray storing wafers is circulated and transported in the circulating transfer path. In the loading device, an empty storage tray is detected from among the plurality of storage trays, and the empty storage tray stores wafers one by one. In the processing apparatus, whether or not the wafer needs processing is detected from the wafer ID, and the processing is performed on the wafer that needs processing. In the carry-in device, the processed wafer is detected from the wafers stored in the plurality of storage trays, and the processed wafer is unloaded from the storage tray. As described above, the processing of each wafer processing apparatus for a wafer is controlled by the presence or absence of the wafer in the storage tray and the wafer ID. This eliminates the need for a host computer that integrally controls each of the wafer processing apparatuses, and can flexibly add or change the number of wafer processing apparatuses. Further, since the wafers are continuously circulated and transferred between the wafer processing apparatuses one by one, the standby time of the subsequent wafer processing apparatus does not become longer as in the case of transferring the wafers in cassette units, and the subsequent The waiting time of the wafer processing apparatus can be minimized. Therefore, it is possible to reduce wasteful waiting time and improve production efficiency.

  Further, in the above-mentioned wafer processing method, each of the processing apparatuses is provided with a mark providing means for providing a processing end mark to the wafer unit after processing is completed, and in the wafer processing step, the wafer is provided by the mark providing means after processing of the wafer is completed. A processing end mark is given to the unit, and in the wafer unloading step, the detection means of the unloading device detects a wafer of the wafer unit to which the processing end mark is given as a processed wafer.

  According to the present invention, since wafers are circulated and transported one by one on a conveyor, wasteful waiting time of a wafer processing apparatus can be reduced and production efficiency can be improved. Further, since the processing of each wafer processing apparatus with respect to the wafer is controlled by the presence or absence of the wafer in the storage tray and the wafer ID, it is possible to flexibly add or change the number of wafer processing apparatuses.

FIG. 1 is a schematic diagram of a wafer processing system according to a first embodiment. FIG. 2 is a schematic diagram of a wafer processing apparatus and a transport mechanism according to the first embodiment. It is a schematic diagram of a storage tray of the first embodiment. FIG. 4 is an explanatory diagram of the wafer processing method according to the first embodiment. It is a schematic diagram of a wafer processing system of a second embodiment. It is an explanatory view of a wafer processing method of a second embodiment. It is an explanatory view of a wafer processing method of a second embodiment.

  Hereinafter, a first embodiment will be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram of a wafer processing system according to the first embodiment. Note that the following wafer processing system is an example, and the present invention is not limited to this configuration. The wafer processing system may be appropriately modified as long as the wafer can be circulated and transferred between the wafer processing apparatuses by the transfer mechanism of the present embodiment.

  As shown in FIG. 1, the wafer processing system 1 includes a plurality of wafer processing apparatuses 2 arranged along a transfer mechanism 3 that circulates and transfers a wafer W (wafer unit WU). The plurality of wafer processing apparatuses 2 include a loading apparatus 2A for loading the wafer W into the transport mechanism 3, processing apparatuses 2B and 2C for processing the wafer W, and an unloading apparatus 2D for unloading the wafer W from the transport mechanism 3. . In this embodiment, the loading device 2A is a mounter, the processing device 2B is a cutting device for a predetermined type of wafer, the processing device 2C is a cutting device for another type of wafer, and the unloading device 2D is a cassette device. ing.

  Note that the cassette device includes a mounting table on which a cassette (accommodating means) can be mounted, and an arm capable of loading or unloading the wafer unit WU with respect to the cassette C. Further, the wafer processing apparatus 2 is not limited to the above-described mounter, cutting apparatus, and cassette apparatus, and may be any apparatus that performs processing on the wafer W. For example, the loading device 2A may be configured by a cassette device, the processing devices 2B and 2C may be configured by grinding devices, and the unloading device 2D may be configured by a die bonder. Since the wafers W are circulated and conveyed, the arrangement order of the respective devices is not limited, but it is preferable to arrange the loading device 2A, the processing devices 2B, 2C, and the unloading device 2D in order from upstream to downstream.

  The surface of the wafer W is divided by a grid-shaped dividing line, and various devices are formed in the divided regions. The wafer W may be a semiconductor wafer in which semiconductor devices are formed on a semiconductor substrate such as silicon or gallium arsenide, or may be an optical device wafer in which an optical device is formed on a ceramic, glass, or sapphire-based inorganic material substrate. Further, the wafer W may be a semiconductor substrate before forming a semiconductor device or an inorganic material substrate before forming an optical device. The wafer W is supported by the annular frame F via the adhesive tape T in the mounter, and is carried into the transfer mechanism 3 as the wafer unit WU.

  By the way, in a general wafer processing system, a plurality of wafer units WU are housed in a cassette, and a plurality of wafer units WU are transported to the wafer processing apparatus in cassette units. However, the time required for processing the wafer W differs depending on the type of the wafer processing apparatus, and the processing on the wafer W is not completed simultaneously in the front and rear wafer processing apparatuses. For example, even if the processing of all the wafers W in the cassette is completed in the subsequent wafer processing apparatus, if the processing of all the wafers W in the cassette is not completed in the previous wafer processing apparatus, the processing of the subsequent wafer W is performed. The cassette is not transported to the device.

  For this reason, useless waiting time occurs in the subsequent wafer processing apparatus. Although the operator can transfer the wafer W completed in the preceding wafer processing apparatus to the subsequent wafer processing apparatus to shorten the waiting time, the burden on the operator increases. Further, in a general wafer processing system, a host computer that controls the plurality of wafer processing apparatuses is provided. The host computer controls the processing timing of each wafer processing apparatus, such as loading, unloading, and processing. Therefore, every time a wafer processing apparatus is added or changed, the configuration of the entire system must be reviewed.

  Therefore, in the wafer processing system 1 of the present embodiment, instead of transporting a plurality of wafer units WU in a cassette at one time, one wafer unit WU is accommodated in the accommodation tray 40 and transported. By transferring the processed wafers W one by one by the conveyor 31 one by one, the standby time of the subsequent wafer processing apparatus 2 is reduced. Further, instead of controlling the whole wafer processing apparatus 2 by the host computer, each of the wafer processing apparatuses 2 sorts the storage tray 40 according to the presence / absence of the wafer W, whether or not the wafer W is a processing target wafer, and the like. The necessary processing is performed for. Thereby, the wafer processing apparatus 2 can be flexibly added and changed without reviewing the entire system.

  In the transfer mechanism 3 of the wafer processing system 1, a conveyor 31 is installed as an annular circulating transfer path along a plurality of wafer processing apparatuses 2, and the wafers W are stored in a plurality of storage trays 40 placed on the conveyor 31. Each sheet is accommodated and circulated and transported. The carry-in device 2A, which is the upstream wafer processing device 2, carries the wafers W one by one onto the plurality of storage trays 40 on the conveyor 31. The processing apparatuses 2B and 2C, which are the midstream wafer processing apparatuses 2, receive and process the wafers W from the plurality of storage trays 40. The unloading device 2D, which is the downstream wafer processing device 2, receives the processed wafer W from the storage tray 40 and unloads it.

  At this time, since an annular circulating transfer path is formed by the plurality of conveyors 31, the empty storage tray 40 and the storage tray 40 storing the wafers W are circulated and transported together. For example, when the processing of the processing apparatus 2B cannot keep up with the loading processing of the loading apparatus 2A, the storage tray 40 storing the unprocessed wafers W is circulated through the processing apparatus 2B. If the unloading process of the unloading device 2D cannot keep up with the processing processes of the processing devices 2B and 2C, the storage tray 40 storing the processed wafers W is circulated and transported through the unloading device 2D. Even if the processing on the downstream side cannot catch up with the processing on the upstream side, the accommodation tray 40 is circulated to enable the processing at the next opportunity.

  For this reason, the loading device 2A selects an empty storage tray 40 from the plurality of storage trays 40 and loads the wafer W into the empty storage tray 40. The processing apparatuses 2B and 2C select the storage tray 40 storing the wafer W to be processed from the plurality of storage trays 40, and process the wafer W to be processed by the processing units 24B and 24C (see FIG. 2). I have. The unloading device 2D sorts the storage trays 40 storing the processed wafers W from the plurality of storage trays 40, and transfers the processed wafers W to the cassette C. As described above, each wafer processing apparatus 2 controls individual processing according to the presence or absence of the wafer W and whether or not the wafer W is a processing target.

  Hereinafter, a wafer processing apparatus and a transfer mechanism will be described with reference to FIGS. FIG. 2 is a schematic diagram of the wafer processing apparatus and the transport mechanism according to the first embodiment. FIG. 3 is a schematic diagram of the storage tray according to the first embodiment.

  As shown in FIG. 2, each of the wafer processing apparatuses 2 has a wafer ID assigned to a storage tray 40 or a wafer unit WU capable of loading and unloading wafers W from a plurality of storage trays 40 circulated and conveyed on the conveyor 31. Detecting means 21A-21D for detecting are provided. More specifically, the carrying-in device 2A is provided with a detection unit 21A that detects an empty storage tray 40. The processing devices 2B and 2C are provided with detection means 21B and 21C for detecting the wafer ID and the empty storage tray 40. The unloading device 2D is provided with detection means 21D for detecting the processed wafer W in the storage tray 40.

  The wafer ID is identification information unique to the wafer including the type of the wafer W and the like, and is detected from, for example, an identification mark 84 (see FIG. 3) such as a barcode, a two-dimensional code, and a character string. In the present embodiment, the identification mark 84 is provided on the surface of the annular frame F. However, the identification mark 84 may be provided on the wafer unit WU, and may be provided on the surface of the adhesive tape T or the surface of the wafer W. It may be attached. Each of the detection units 21A to 21D may be, for example, a CCD (Charge Coupled Device) camera, a C-MOS (Complementary-Metal Oxide Semiconductor) camera, a transmission sensor, It is composed of a code reader and the like.

  Each wafer processing apparatus 2 is provided with transfer means 22A to 22D for transferring wafers W to and from a plurality of storage trays 40 circulated and conveyed on the conveyor 31. The transfer means 22A of the loading device 2A transfers and carries the wafer W from the loading device 2A to the storage tray 40. The transfer units 22B and 22C of the processing devices 2B and 2C transfer the wafer W from the storage tray 40 to the processing devices 2B and 2C, and transfer the wafer W from the processing devices 2B and 2C to the storage tray 40. The transfer means 22D of the unloading device 2D transfers and unloads the wafer W from the storage tray 40 to the unloading device 2D.

  Further, each wafer processing apparatus 2 is provided with regulating means 23A-23D for regulating the circulating conveyance of the storage tray 40 by the conveyor 31 when the wafer W is transferred. Each of the restricting units 23A to 23D protrudes so as to block the circulating transfer path on the downstream side of each of the transfer units 22A to 22B, and restricts the transfer of the storage tray 40 at the transfer position of the wafer W. The conveyor 31 is also driven during the regulation of the storage tray 40 by the regulating means 23A to 23D, and the installation surface of the conveyor 31 slides on the back surface of the storage tray 40 so that the storage tray 40 is not transported. Therefore, conveyance of another storage tray 40 on the same conveyor 31 is not restricted.

  These detection means 21A-21D, delivery means 22A-22D, and regulation means 23A-23D are controlled by control means 25A-25D, respectively. The detection means 21A-21D are disposed upstream of the delivery means 22A-22D and the regulation means 23A-23D, and output detection results to the control means 25A-25D before the storage tray 40 reaches the delivery position. are doing. Each of the control units 25A to 25D controls the transfer operation of the wafer W by the transfer units 22A to 22D and the restricting operation of the storage tray 40 by the restricting units 23A to 23D according to the detection result by the detecting units 21A to 21D. .

  More specifically, in the loading device 2A, when the empty storage tray 40 is detected by the detection unit 21A, the control unit 25A instructs the regulating unit 23A and the transfer unit 22A to perform the loading process of the wafer W (wafer unit WU). You. Thus, the storage tray 40 that has passed through the detection unit 21A is stopped by the restriction unit 23A, and the unprocessed wafer W is loaded into the storage tray 40 by the transfer unit 22A. The carry-in device 2A selects an empty storage tray 40 in which no wafer W is stored from among the plurality of storage trays 40 circulated and conveyed on the conveyor 31, and processes an unprocessed wafer with respect to the empty storage tray 40. W is housed.

  In the processing apparatus 2B, when the detection unit 21B detects the wafer ID, the control unit 25B compares the detected wafer ID with the processing target wafer ID stored in the memory in advance. When the wafer ID detected by the detection unit 21B matches the wafer ID in the memory, the control unit 25B instructs the regulating unit 23B and the transfer unit 22B to process the wafer W. Thus, the storage tray 40 that has passed through the detection unit 21B is stopped by the restriction unit 23B, and the wafer W is received from the storage tray 40 to the transfer unit 22B. The processing means 24B processes the wafer W according to the processing conditions for the wafer ID stored in the memory in advance.

  Further, in the processing apparatus 2B, when the empty storage tray 40 is detected by the detection unit 21B after the processing of the wafer W is completed, the control unit 25B instructs the regulating unit 23B and the transfer unit 22B to transfer the wafer W. Accordingly, the storage tray 40 that has passed through the detection unit 21B is stopped by the restriction unit 23B, and the processed wafer W is transferred to the storage tray 40 by the transfer unit 22B. In the processing apparatus 2C, similarly to the processing apparatus 2B, the processing of the wafer W and the delivery of the wafer W to the empty storage tray 40 are controlled in accordance with the detection result of the detection unit 21C.

  In the unloading device 2D, when the processed wafer W is detected by the detection unit 21D, the control unit 25D instructs the regulating unit 23D and the transfer unit 22D to perform the unloading process of the wafer W (wafer unit WU). Thereby, the storage tray 40 that has passed through the detection unit 21D is stopped by the restriction unit 23D, and the processed wafer W received by the transfer unit 22D is unloaded from the storage tray 40. The unloading device 2D selects the storage tray 40 storing the processed wafer W among the plurality of storage trays 40 circulated and transported on the conveyor 31, and unloads the processed wafer W from the storage tray 40. ing.

  Note that the empty storage trays 40 may be sorted according to, for example, an imaging result of the storage trays 40. When the wafer W is not included in the captured image of the storage tray 40, the wafer W is sorted as an empty storage tray 40. When the wafer W is included in the captured image of the storage tray 40, the wafer W is stored. The storage tray 40 is selected. Further, the empty storage tray 40 may be selected by reading the identification mark 84 (see FIG. 3), for example. If the identification mark 84 cannot be read, it is selected as an empty storage tray 40, and if the identification mark 84 can be read, it is selected as the storage tray 40 storing the wafer W.

  Further, whether the wafer W is an unprocessed wafer W or a processed wafer W may be selected according to the surface state of the wafer W, for example. When there is no cutting mark on the surface of the wafer W, the wafer W is sorted as an unprocessed wafer W, and when there is a cutting mark on the surface of the wafer W, it is sorted as a processed wafer W. Further, whether the wafer is an unprocessed wafer W or a processed wafer W may be selected in accordance with, for example, a processing end mark (FIGS. 7A and 7C) described later, which is given to the wafer unit WU. When the processing accommodation mark is not attached, the wafer is sorted as an unprocessed wafer W, and when the processing accommodation mark is attached, the wafer is sorted as a processed wafer W.

  Further, the control means 25A to 25D are configured by a processor, a memory, and the like that execute various processes of each unit of the apparatus. The memory includes one or a plurality of storage media such as a ROM (Read Only Memory) and a RAM (Random Access Memory) depending on the application. The memory stores, for example, programs for executing various processes. In particular, the memories of the processing apparatuses 2B and 2C store a wafer ID for identifying the wafer W to be processed. By storing different wafer IDs in the memories of the processing apparatuses 2B and 2C, the wafer W being transported is sorted and processed by the processing apparatus 2B and the processing apparatus 2C.

  As shown in FIG. 1, the transport mechanism 3 forms a circulating transport path for a plurality of storage trays 40 by arranging a plurality of conveyors 31 in a ring shape. On the plurality of conveyors 31, a pair of guide rails 33 (see FIG. 1) are arranged along the circulating conveyance path, and the circulating conveyance of the storage tray 40 is guided by the pair of guide rails 33. The storage tray 40 is a shallow box-shaped container having an open upper surface, and stores the wafer unit WU in a positioned state. In FIG. 2, the conveyor 31 is described as a belt conveyor, but the conveyor 31 may be a roller conveyor or the like as long as it can transport the storage tray 40.

  The storage trays 40 storing the wafers W in the loading device 2A are sequentially sent out to the processing devices 2B and 2C by the conveyor 31. That is, the wafers W stored in the storage tray 40 are transferred one by one to the processing apparatuses 2B and 2C. When the wafer W is stored in the empty storage tray 40 by the loading device 2A, the wafer W is transported by the conveyor 31 to the downstream processing devices 2B and 2C without a pause. Therefore, since the wafer W is continuously transferred to the processing apparatuses 2B and 2C, the waiting time does not become long unlike the case where the wafer W is transferred in a cassette unit.

  In the wafer processing system 1, the processing time for the wafer W by the processing devices 2B and 2C is longer than the time for loading the wafer W into the storage tray 40 by the loading device 2A. For this reason, if the wafer W is carried into all the storage trays 40 on the conveyor 31 by the carrying-in device 2A during the working of the working devices 2B and 2C, the processed wafer W is removed from the working devices 2B and 2C. It cannot be stored in the storage tray 40. For this reason, at least one of the plurality of storage trays 40 on the conveyor 31 is secured as the processed wafer storage tray 49 that stores only the processed wafer W.

  Since the wafers W are not loaded into the processed wafer storage tray 49 from the loading device 2A, all the storage trays 40 on the conveyor 31 are not used for transporting unprocessed wafers W. The processed wafer storage tray 49 is provided with a mark Ma for distinguishing it from the normal storage tray 40. The loading device 2A is set to regulate the loading of the wafer W into the processed wafer tray 49 to which the mark Ma has been given. The detection means 21A of the loading device 2A detects the presence or absence of the mark Ma on the storage tray 40, thereby selecting the normal storage tray 40 and the processed wafer storage tray 49, and transferring the wafer W only to the normal storage tray 40. I am carrying it. The mark Ma is not particularly limited as long as the normal storage tray 40 and the processed wafer storage tray 49 can be identified.

  Further, in the present embodiment, the length of the conveyor 31 is designed according to each wafer processing apparatus 2. That is, the single conveyor 31 constitutes one segment of the circulating transport path, and the wafer processing apparatus 2 corresponds to one segment of the circulating transport path. Therefore, by changing the number of the conveyors 31, the number of segments in the circulating transport path can be adjusted. By allocating the wafer processing apparatus 2 to each segment, the expansion or change of the wafer processing apparatus 2 can be flexibly performed. it can. In addition, since the circulation path is divided into a plurality of segments by the conveyor 31, the path and the overall length can be easily changed.

  As shown in FIG. 3A, on the outer periphery of the annular frame F of the wafer unit WU, two parallel flat surfaces 81 facing each other in one direction and two parallel flat surfaces 82 facing each other in a direction orthogonal to one direction. Are formed. The storage tray 40 is formed in a box shape having an opening on the upper surface and having a size capable of storing the wafer unit WU. On the bottom surface of the storage tray 40, a plurality of mounting portions 41 on which the annular frame F of the wafer unit WU can be mounted are provided. Each mounting portion 41 projects hemispherically from the bottom surface of the storage tray 40, supports the annular frame F, and separates the back surface of the wafer unit WU from the bottom surface of the storage tray 40.

  Further, a plurality of first positioning rollers 43 are disposed on the opening edge of the storage tray 40 so as to face each other, and the plurality of second positioning rollers 43 are arranged in a direction orthogonal to the direction in which the first positioning rollers 43 face each other. Rollers 44 are provided facing each other. The first positioning roller 43 is provided at a position corresponding to the flat surface 81 of the annular frame F, and the second positioning roller 44 is provided at a position corresponding to the flat surface 82 of the annular frame F. The first and second positioning rollers 43 and 44 are supported at locations where the side walls of the storage tray 40 are cut out, and are slightly separated from the wall surfaces of the side walls of the storage tray 40 so as to be able to roll on the annular frame F. The roller surface is protruding.

  When the wafer unit WU is stored in the storage tray 40 from above by the transfer means 22A (see FIG. 2) of the loading device 2A, the flat surfaces 81, 82 of the annular frame F are moved by the first and second positioning rollers 43, 44. Positioned. The annular frame F is placed on the placing portion 41 in a state where the annular frame F is positioned by the first and second positioning rollers 43 and 44. As described above, the storage tray 40 positions the wafer unit WU in the front, rear, left, and right directions by the flat surfaces 81, 82 of the annular frame F rollingly contacting the first and second positioning rollers 43, 44, and one sheet in this state. Of wafer units WU. As shown in FIG. 3B, the processed wafer storage tray 49 has the same configuration as the normal storage tray 40 except that a mark Ma is attached.

  Subsequently, a wafer processing method will be described with reference to FIG. FIG. 4 is an explanatory diagram of the wafer processing method according to the first embodiment. Note that the wafer processing method shown in FIG. 4 is an example, and can be appropriately changed. 4 shows a top view of the storage tray immediately below the detection means. In the following description, an example in which a wafer is processed by the processing device 2B will be described, but the same applies to a case where a wafer is processed by the processing device 2C.

  As shown in FIG. 4A, in the wafer loading step, an empty storage tray 40 that can be loaded is detected by the detection unit 21A from the plurality of storage trays 40 that are transported toward the loading device 2A. When an empty storage tray 40 is detected, one transfer wafer 22A is carried into the storage tray 40 by the transfer unit 22A in a state where the transfer of the storage tray 40 is restricted by the restriction unit 23A. On the other hand, when the storage tray 40 storing the wafer W is detected, the storage tray 40 is transported downstream without being restricted by the restricting means 23A. When the empty storage tray 40 is the processed wafer storage tray 49 (see FIG. 3B), the empty storage tray 40 is transported downstream without being restricted by the restricting means 23A.

  As shown in FIG. 4B, in the wafer processing step, the wafer ID of the wafer W to be processed is detected by the detection unit 21B from the wafers W of the plurality of storage trays 40 conveyed toward the processing apparatus 2B. When the processing target wafer ID is detected, the transfer target 22B receives the processing target wafer W from the storage tray 40 in a state where the transport of the storage tray 40 is controlled by the control unit 23B. In the processing apparatus 2B, the wafer W is processed by the processing means 24B (see FIG. 2). On the other hand, when a wafer ID different from the processing target is detected, the storage tray 40 is transported downstream without being restricted by the restriction means 73B.

  As shown in FIG. 4C, in the processed wafer delivery step, the empty storage tray 40 is detected by the detection unit 21B from among the plurality of storage trays 40 conveyed toward the processing apparatus 2B. When the empty storage tray 40 is detected, the processed wafer W is transferred to the storage tray 40 by the transfer unit 22B in a state where the transport of the storage tray 40 is controlled by the control unit 23B. On the other hand, when the storage tray 40 storing the wafer W is detected, the storage tray 40 is transported downstream without being restricted by the restriction means 23B. Note that even if the empty storage tray 40 is the processed wafer storage tray 49 (see FIG. 3B), the processed wafer W is transferred to the storage tray 40 by the transfer unit 22B.

  As shown in FIG. 4D, in the wafer unloading step, the processed wafer W is detected by the detection unit 21D from among the wafers W in the plurality of storage trays 40 transported toward the unloading device 2D. When the processed wafer W is detected, the processed wafer W is received from the storage tray 40 by the transfer unit 22D in a state where the transport of the storage tray 40 is restricted by the restriction unit 23D. Thus, the processed wafer W is unloaded from the conveyor 31. On the other hand, when an unprocessed wafer or an empty storage tray 40 is detected, the storage tray 40 is transported downstream without being restricted by the restriction means 23D.

  As described above, in the wafer processing method of the first embodiment, since the wafers W are continuously circulated and transferred one by one between the wafer processing apparatuses 2, the wafer W is transferred in a cassette unit. Therefore, the standby time of the subsequent wafer processing apparatus 2 does not increase, and the standby time of the subsequent wafer processing apparatus 2 can be minimized. Therefore, it is possible to reduce wasteful waiting time and improve production efficiency. In addition, in addition to the empty storage tray 40, the storage tray 40 storing the wafers W is circulated and transported in the circulating transfer path. A series of processing of each wafer processing apparatus 2 is controlled. For this reason, a host computer which controls each wafer processing apparatus 2 is unnecessary, and expansion or change of the wafer processing apparatus 2 can be flexibly performed.

  In the wafer processing system according to the first embodiment, the wafer is processed by one of the two types of processing apparatuses. However, the wafer is processed stepwise by the two types of processing apparatuses. Is also good. Hereinafter, a wafer processing method of the wafer processing system according to the second embodiment will be described. FIG. 5 is a schematic diagram of a wafer processing system according to the second embodiment. The wafer processing system according to the second embodiment is different from the first embodiment in that a processing end mark is added to a wafer unit in each processing apparatus. Therefore, only points different from the first embodiment will be described, and description of the common configuration will be omitted as much as possible.

  As shown in FIG. 5, in the second wafer processing system 51, a circulating transport path of a transport mechanism 53 is formed by a plurality of conveyors 61, and a loading device 52A, a processing device 52B, a processing device 52C and an unloading device 52D are arranged. In the loading device 52A, the wafer W is loaded into the storage tray 40 on the conveyor 61, and in the processing device 52B, the first processing is performed on the wafer W. In the processing device 52C, the second processing is performed on the first processed wafer W, and in the unloading device 52D, the second processed wafer W is unloaded from the storage tray 40 on the conveyor 61.

  In this embodiment, the loading device 52A is a mounter, the processing device 52B is a laser processing device, the processing device 52C is a cutting device, and the unloading device 52D is a cassette device. In the processing device 52B, the wafer W is ablated along the planned dividing line, and a processing groove along the planned dividing line is formed on the surface of the wafer W. In the processing device 52C, the ablation-processed wafer W is cut along the processing groove, and the wafer W is divided into individual chips. Thus, the wafer W is processed in two stages by the processing device 52B and the processing device 52C.

  The processing device 52B and the processing device 52C respectively have mark providing means 76B and 76C (see FIGS. 7A and 7C) for providing processing end marks M1 and M2 (see FIGS. 7A and 7C) to the wafer unit WU after the processing by the processing means 74B and 74C. 6B and 7A). The mark providing means 76B of the processing device 52B gives the processing end mark M1 to the wafer unit WU after the processing by the processing means 74B is completed. The mark providing means 76C of the processing device 52C gives the processing end mark M2 to the wafer unit WU after the processing by the processing means 74C is completed.

  Note that the mark providing units 76B and 76C (see FIGS. 6B and 7A) can respectively add the processing end marks M1 and M2 to the wafer unit WU by an arbitrary method. For example, the marking means 76B and 76C are laser marking on the adhesive tape T or the wafer W, stick a bar code on the adhesive tape T, ink marking on the adhesive tape T or the wafer W (defective chip marking), etc. M2 may be provided. In addition, if the first and second processed wafers W can be sorted according to the surface state (calf) of the wafer W, the mark applying units 76B and 76C are unnecessary.

  Further, the wafer processing apparatus 52 is not limited to the above-described mounter, laser processing apparatus, cutting apparatus, and cassette apparatus, and may be any apparatus that performs processing on the wafer W. For example, the loading device 52A may be configured by a cassette device, the processing device 52B may be configured by a cutting device for half cutting, the processing device 52C may be configured by a cutting device for full cutting, and the unloading device 52D may be configured by a die bonder. Since the wafer W is circulated and transported, the arrangement order of the respective devices is not limited. However, it is preferable to arrange the loading device 52A, the processing device 52B, the processing device 52C, and the unloading device 52D in order from upstream to downstream.

  Ablation means that when the irradiation intensity of a laser beam exceeds a predetermined processing threshold, it is converted into electron, thermal, photochemical and mechanical energy on the solid surface, and as a result, neutral atoms, molecules, positive and negative ions , Radicals, clusters, electrons, and light are explosively emitted and the solid surface is etched.

  Subsequently, a wafer processing method will be described with reference to FIGS. 6 and 7 are explanatory diagrams of the wafer processing method according to the second embodiment. The wafer processing method shown in FIGS. 6 and 7 is an example, and can be appropriately changed. The right side in FIGS. 6 and 7 is a top view of the storage tray immediately below the detection means.

  As shown in FIG. 6A, in the wafer loading step, an empty loading tray 40 that can be loaded is detected by the detection unit 71A from the plurality of loading trays 40 that are transported toward the loading device 52A. When an empty accommodation tray 40 is detected, one wafer W is carried into the accommodation tray 40 by the transfer means 72A in a state where the conveyance of the accommodation tray 40 is regulated by the regulation means 73A. On the other hand, when the storage tray 40 storing the wafer W is detected, the storage tray 40 is transported downstream without being restricted by the restriction means 73A. When the empty storage tray 40 is the processed wafer storage tray 49 (see FIG. 3B), the empty storage tray 40 is transported downstream without being restricted by the restriction means 73A.

  As shown in FIG. 6B, in the first wafer processing step, the wafer ID of the wafer W to be processed is detected by the detecting means 71B from the wafers W of the plurality of storage trays 40 conveyed toward the processing apparatus 52B. Is done. When the processing target wafer ID is detected, the transfer target 72B receives the processing target wafer W from the storage tray 40 in a state where the transport of the storage tray 40 is restricted by the restriction means 73B. In the processing device 52B, the wafer W is processed by the processing means 74B, and after the processing is completed, a processing end mark M1 (see FIG. 7A) is applied to the adhesive tape T by the mark applying means 76B. On the other hand, when a wafer ID different from the processing target is detected, the storage tray 40 is transported downstream without being restricted by the restriction means 73B.

  As shown in FIG. 6C, in the first processed wafer delivery step, the empty storage tray 40 is detected by the detection unit 71B from the plurality of storage trays 40 conveyed toward the processing device 52B. When the empty storage tray 40 is detected, the processed wafer W is transferred to the storage tray 40 by the transfer unit 72B in a state where the transfer of the storage tray 40 is controlled by the control unit 73B. On the other hand, when the storage tray 40 storing the wafer W is detected, the storage tray 40 is transported downstream without being restricted by the restriction means 73B. Note that, even when the empty storage tray 40 is the processed wafer storage tray 49 (see FIG. 3B), the processed wafer W is transferred to the storage tray 40 by the transfer unit 72B.

  As shown in FIG. 7A, in the second wafer processing step, the wafer ID and the processing of the wafer W to be processed by the detecting unit 71C are selected from the wafers W of the plurality of storage trays 40 conveyed toward the processing apparatus 52C. The end mark M1 is detected. When the processing target wafer ID and the processing end mark M1 are detected, the transfer target 72C receives the processing target wafer W from the storage tray 40 in a state where the transport of the storage tray 40 is restricted by the restriction means 73C. That is, the detecting unit 71C detects the wafer W of the wafer unit WU to which the processing end mark M1 has been given as the first processed wafer W. In the processing device 52C, the wafer W is processed by the processing means 74C, and after the processing is completed, the processing end mark M2 is applied to the adhesive tape T by the mark applying means 76C. On the other hand, the storage tray 40 for the wafer W not to be processed and the storage tray 40 for the unprocessed wafer W (the wafer W not provided with the processing end mark M1) are directed downstream without being restricted by the restriction means 73C. Conveyed.

  As shown in FIG. 7B, in the second processed wafer delivery step, the empty storage tray 40 is detected by the detection unit 71C from the plurality of storage trays 40 conveyed toward the processing device 52C. When the empty storage tray 40 is detected, the processed wafer W is transferred to the storage tray 40 by the transfer unit 72C in a state where the transfer of the storage tray 40 is controlled by the control unit 73C. On the other hand, when the storage tray 40 storing the wafer W is detected, the storage tray 40 is transported downstream without being restricted by the restriction means 73C. Even if the empty storage tray 40 is the processed wafer storage tray 49 (see FIG. 3B), the processed wafer W is transferred to the storage tray 40 by the transfer unit 72C.

  As shown in FIG. 7C, in the wafer unloading step, the processing completion mark M2 is detected by the detection unit 71D from the wafers W of the plurality of storage trays 40 transported toward the unloading device 52D. When the processed end mark M2 is detected, the processed wafer W is received from the storage tray 40 by the transfer unit 72D in a state where the transport of the storage tray 40 is restricted by the restriction unit 73D. That is, the detection unit 71D detects the wafer W of the wafer unit W to which the processing end mark M2 has been given as the second processed wafer W. Thus, the processed wafer W is unloaded from the conveyor 61. On the other hand, the empty storage tray 40, the unprocessed wafer W, and the storage tray 40 for the first processed wafer W (the wafer W to which only the processing end mark M1 is added) are downstream without being restricted by the restriction means 73D. Conveyed toward.

  As described above, in the wafer processing method according to the second embodiment, similarly to the wafer processing method according to the first embodiment, unnecessary standby time of the wafer processing apparatus 52 is reduced and the production efficiency is improved. be able to. In addition, a host computer for controlling each wafer processing apparatus 52 is not required, and the addition or change of the wafer processing apparatuses 52 can be flexibly performed. Furthermore, since the first processed wafer W and the second processed wafer W are sorted according to the processing end marks M1 and M2, the first processed wafer W and the second processed wafer W are separated. Appropriate processing can be performed on the wafer W.

  Note that the present invention is not limited to the above embodiment, and can be implemented with various modifications. In the above embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited thereto, and can be appropriately changed within a range in which the effects of the present invention are exhibited. In addition, the present invention can be appropriately modified and implemented without departing from the scope of the object of the present invention.

  For example, in the above-described first and second embodiments, the storage tray 40 is formed of a shallow box-shaped container provided with the first and second positioning rollers 43 and 44. It can be changed as appropriate. The storage tray 40 may have any configuration as long as the storage unit 40 can store the wafer unit WU.

  In the first and second embodiments, at least one of the plurality of storage trays 40 is the processed wafer storage tray 49. However, the processed wafer storages are stored in the plurality of storage trays 40. The tray 49 may not be included at all.

  Further, in the first and second embodiments described above, the transport of the storage tray 40 is restricted by the control means 23A-23D, 73A-73D being abutted against the storage tray 40. The transport of the storage tray 40 may be restricted by the structure.

  In the second embodiment, the wafer W is processed in two stages by two types of processing devices. However, the wafer W may be processed in three or more stages by three or more types of processing devices.

  As described above, the present invention has an effect of reducing unnecessary standby time of a wafer processing apparatus, and is particularly useful for a wafer processing method in which wafers are circulated and transported among a plurality of wafer processing apparatuses. It is.

1, 51 Wafer processing system 2, 52 Wafer processing device 2A, 52A Loading device 2B, 52B Processing device 2C, 52C Processing device 2D, 52D Unloading device 3, 53 Transport mechanism 21A-21D, 71A-71D Detecting means 22A-22D, 72A-72D Delivery means 31, 61 Conveyor 40 Storage tray 49 Wafer storage tray 76B, 76C Marking means 84 Wafer ID
F Annular frame M1, M2 Processing end mark T Adhesive tape W Wafer WU Wafer unit

Claims (2)

The transfer mechanism transports the wafers one by one between a plurality of wafer processing apparatuses configured to support the wafers through the adhesive tape in the openings of the annular frame via the adhesive tape and to process the wafers of the wafer units to which the wafer IDs are assigned. A wafer processing method for performing a series of processing
The transfer mechanism includes a conveyor as an annular circulating transfer path provided along a plurality of wafer processing apparatuses, and a plurality of storages that store wafers one by one and that are circulated and mounted on the conveyor. With a tray,
A plurality of wafer processing apparatuses, a loading apparatus for loading wafers one by one onto the plurality of storage trays on the conveyor, and a processing apparatus for receiving and processing wafers from the plurality of storage trays on the conveyor; A carry-out device that receives a processed wafer processed in the processing device from a storage tray on the conveyor and carries it out,
Each wafer processing apparatus has a detection means for detecting a storage tray or a wafer ID capable of loading and unloading wafers from the plurality of storage trays circulated on the conveyor, and the plurality of storage trays circulated on the conveyor. Transfer means for transferring a wafer between each of the wafer processing apparatuses,
The detection unit of the loading device detects an empty storage tray that can be loaded from among the plurality of storage trays that are circulated and conveyed, and the delivery unit of the loading device transfers one wafer to the empty storage tray on a conveyor. A wafer loading step for loading into the receiving tray;
The detection means of the processing device detects a wafer ID of a wafer to be processed from among the plurality of storage trays circulated and conveyed, and the transfer means of the processing device transfers the wafer to be processed from the storage tray. A wafer processing step of receiving and processing the wafer;
After performing the wafer processing step, the detection unit of the processing apparatus detects an empty storage tray that can be carried in from the plurality of storage trays that are circulated and conveyed, and the receiving unit of the processing apparatus has already processed the storage tray. Transferring a wafer to the empty receiving tray, a processed wafer transfer step,
A wafer unloading step in which the detecting means of the unloading device detects the processed wafer to be circulated and conveyed, and the transfer means of the unloading device receives the processed wafer from the storage tray, and unloads the processed wafer from the conveyor. ,
Equipped with a,
A wafer processing method, wherein at least one of the plurality of storage trays is a processed wafer storage tray capable of storing only processed wafers . Each of the processing apparatuses includes a mark imparting unit that imparts a processing end mark to the wafer unit after the processing is completed,
In the wafer processing step, after the processing of the wafer is completed, a processing completion mark is provided to the wafer unit by the mark providing means,
2. The wafer processing method according to claim 1, wherein, in the wafer unloading step, the detection unit of the unloading device detects a wafer of the wafer unit to which the processing end mark is given as a processed wafer.

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