JP2015191992A - Semiconductor production apparatus and method of producing semiconductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor production apparatus capable of cutting a wafer easily at a low cost while reducing impact on the wafer quality, and capable of dicing a wafer without using a dicer corresponding to large diameter, even if the diameter of the wafer is increased, and to provide a method of producing a semiconductor.SOLUTION: A semiconductor production apparatus sticks a back grinding tape GT to the surface side, and divides a wafer W, which was ground on the back surface side, into multiple pieces. The production apparatus includes a laser irradiation section 14 which has a laser unit 141, for irradiating the back grinding tape GT on the wafer W with laser by means of the laser unit 141, dividing the back grinding tape GT into multiple pieces, and forming division lines L2X, L2Y for cutting the wafer W, by irradiating the surface of the wafer W with laser along the divided lines L1X, L1Y of the back grinding tape GT.

Description

  The present invention relates to a semiconductor manufacturing apparatus and a semiconductor manufacturing method, and in particular, a laser is applied to a wafer that has been ground on the back side by attaching a back grinding tape to the front side, and is used for cutting inside the wafer. The present invention relates to a semiconductor manufacturing apparatus and a semiconductor manufacturing method for forming a modified layer and dividing a wafer into a plurality of parts.

  Conventionally, in general, the back surface of a semiconductor wafer (simply referred to as “wafer”) on which a semiconductor device or electronic component is formed is ground, and then diced to be divided into chips such as ICs. A ring frame having a corresponding size and a dicing tape attached thereto and a dicing apparatus having a chuck table have been required (for example, see Patent Document 1). That is, for example, when dicing a wafer having an outer diameter of 300 mm, a dicing apparatus provided with a ring frame having an inner diameter of 350 mm and a chuck table for 300 mm is used.

  Also, the diameter of the wafer has been increasing year by year with the aim of improving productivity, and today the maximum outer diameter is increased from 300 mm to 450 mm. This trend will continue and is expected to become even larger. Along with this, the diameter of wafer mounters for mounting wafers, die bonders for bonding chips to package substrates, dicing tape and ring frames used for individualization, and carriers for storing them are also increased. It is necessary to prepare for. For this reason, it is expected that cost and time will be required.

  Therefore, conventionally, after mounting a large-diameter wafer on a ring frame on which a dicing tape is attached, it is set together with the ring frame on a large-diameter dicer, and the large-diameter wafer is divided into four or more small parts. There has also been proposed a dicing system in which the divided wafer is diced by a small-diameter dicer and divided into chips such as ICs (see, for example, Patent Document 2).

JP 2007-27562 A. Japanese Patent Laid-Open No. 9-148275.

  The technique disclosed in Patent Document 2 divides a large-diameter wafer into four or more, and enables the division processing with a small-diameter dicer. However, such a method requires at least one large-diameter dicer that divides a large-diameter wafer into four or more. For this reason, in order to divide a large-diameter wafer, it is necessary to prepare a dicer corresponding to the large-diameter, and there is a problem that costs and time are required.

In addition, a blade is used to cut the wafer. The cutting with the blade has the following problems (1) to (3).
(1) Since the blade cuts the back grinding tape and the wafer at the same time, there is a concern about the influence on the quality.
(2) In processing using a blade, it is necessary to supply cooling water or the like to the processing portion, so that it is necessary to prepare an environment (function) in which water is used, which is expensive.
(3) In processing with a blade, it is necessary to select a blade according to the processing target, which is troublesome.

  Therefore, it is possible to cut the wafer easily and at low cost with less impact on the wafer quality, and even if the diameter of the wafer is increased, a dicer corresponding to the increased diameter is not used. The technical problem which should be solved in order to provide the semiconductor manufacturing apparatus and semiconductor manufacturing method which enable dicing arises, and this invention aims at solving this problem.

  The present invention has been proposed in order to achieve the above object, and the invention according to claim 1 includes a plurality of wafers in which the back side grinding tape is pasted on the front side and the back side grinding is finished. In the semiconductor manufacturing apparatus to be divided, the apparatus has laser irradiation means, and the laser irradiation means irradiates the back grinding tape on the wafer with a laser to divide the back grinding tape into a plurality of pieces, and Provided is a semiconductor manufacturing apparatus including a laser irradiation unit that irradiates a surface of the wafer with a laser along a divided line of a backgrinding tape to form a dividing line for wafer cutting on the wafer.

According to this configuration, first, (1) the laser is irradiated to the back grinding tape attached to the surface of the thinned wafer after the grinding by the laser irradiation means provided in the laser irradiation unit. The back grinding tape is divided into at least three. As a result, a line-shaped gap is created between the divided back grinding tapes, and the back grinding tape is removed from the surface of the wafer at the gaps so that the surface of the wafer is substantially exposed.
(2) Next, the laser is irradiated by the laser irradiation means provided in the laser irradiation section along the tape dividing line where the back grinding tape is divided, that is, along the gap, and the wafer is divided for wafer cutting. Form a line. At that time, due to the cutting of the previous backgrinding tape, the backgrinding tape was almost removed from the surface of the wafer and exposed at the surface portion of the wafer corresponding to the tape splitting line of the backgrinding tape. Is in a state.
(3) Therefore, the laser irradiated to the wafer surface along the tape cutting line is irradiated to the substantially same depth position of the wafer, and the wafer cutting dividing line consisting of the modified portion of the same depth is applied to the wafer surface. Form on the side. As a result, the wafer can be cleaved (divided) with high precision along the wafer cutting dividing line.
(4) Even if the diameter of the wafer is increased due to this cleaving, dicing can be performed using a conventional dicer for small diameter without using a dicer corresponding to the increase in diameter. .

  2. The semiconductor manufacturing apparatus according to claim 2, wherein the tape dividing line and the wafer cutting dividing line are formed in a substantially cross shape through substantially the center of the wafer. Providing manufacturing equipment.

  According to this configuration, it is possible to easily form the tape dividing line and the wafer cutting dividing line by scanning the laser in the X and Y directions by the laser irradiation means provided in the laser irradiation unit.

The semiconductor manufacturing apparatus according to claim 3 is the apparatus according to claim 1 or 2, wherein the laser irradiation unit irradiates the back grinding tape and the wafer with a short wavelength laser.
A semiconductor manufacturing apparatus is provided.

  According to this configuration, when the back grinding tape is divided, for example, when a laser having a short wavelength of about 266 nm is irradiated toward the back grinding tape, the influence of the heat on the back grinding tape is not affected. Only a small amount of the backgrinding tape can be cut without melting the wafer. On the other hand, when forming a wafer cut line, if the surface of the wafer is irradiated with a laser along the tape cutting line, the laser is irradiated to almost the same depth position of the wafer, and the modification of the same depth is performed on the surface side of the wafer. It is possible to form a wafer-cut dividing line consisting of parts. As a result, the wafer can be cleaved (divided) with high accuracy along the wafer-cutting dividing line into smaller pieces.

  According to a fourth aspect of the present invention, in the semiconductor manufacturing apparatus according to the first, second, or third aspect, the wafer is set with the surface side facing downward, and the laser irradiation means causes the laser to be placed on the wafer. Provided is a semiconductor manufacturing apparatus for irradiation from the lower side.

  According to this configuration, the laser irradiation port by the laser irradiation unit is disposed below the wafer. As a result, when performing the cleaning work of the laser irradiation port, etc., the work should be easily carried out with a natural posture so as not to impose an unreasonable posture on the operator even from the viewpoint of visual and work. Can do. Further, for example, a measure for reducing the number of cleanings by providing a blow or the like can be easily introduced.

  According to a fifth aspect of the present invention, there is provided a semiconductor manufacturing method in which a back grinding tape is attached to the front surface side and the back surface grinding is divided into a plurality of wafers. Ablation processing step of irradiating and dividing the backgrinding tape into a plurality of pieces, and irradiating the surface of the wafer with a laser along the tape cutting line of the backgrinding tape, and dividing the wafer into wafer cuts A method of manufacturing a semiconductor, comprising: a wafer cut line forming step of forming a line; and a wafer dividing step of breaking the wafer along the wafer cutting dividing line to divide the wafer into a plurality of fragmented wafers. provide.

According to this method, (1) a back grinding tape attached to the surface of a thinned wafer after grinding is irradiated with laser in ablation processing, and at least three back grinding tapes are used. Divide into the above. As a result, a line-shaped gap is formed between the divided back grinding tapes, and the back grinding tape is removed from the surface of the wafer at the gap, so that the surface of the wafer is substantially exposed.
(2) Next, in the wafer cut line forming step, the laser is irradiated on the surface of the wafer along the divided part of the backgrinding tape, that is, along the gap, and a dividing line for cutting the wafer is formed on the wafer. To do. At this time, due to the cutting of the previous backgrinding tape, the backgrinding tape was almost removed from the surface of the wafer and exposed at the surface portion of the wafer corresponding to the tape dividing line of the backgrinding tape. Is in a state.
(3) Therefore, the laser irradiated to the wafer surface along the tape cutting line is irradiated to the substantially same depth position of the wafer, and the wafer cutting dividing line consisting of the modified portion of the same depth is applied to the wafer surface. Form on the side. As a result, the wafer can be cleaved (divided) with high accuracy along the wafer-cutting dividing line into smaller pieces.
(4) Even if the diameter of the wafer is increased due to this cleaving, dicing can be performed using a conventional dicer for small diameter without using a dicer corresponding to the increase in diameter. .

  According to a sixth aspect of the present invention, in the method of the fifth aspect, the tape dividing line and the wafer cutting dividing line are formed in a substantially cross shape through substantially the center of the wafer. Provide a method.

  According to this method, it is possible to easily form the tape dividing line and the wafer cutting dividing line by scanning the laser in the X and Y directions.

  The invention according to claim 7 provides the method for manufacturing a semiconductor according to claim 5 or 6, wherein the laser in the ablation processing step and the laser in the wafer cut line forming step have a short wavelength. .

  According to this method, in the ablation process, when the back grinding tape is irradiated with a laser having a short wavelength of about 266 nm, for example, the influence of heat on the back grinding tape is small, and the wafer is Only the backgrinding tape can be divided without melting. On the other hand, when a laser is applied to the wafer surface along the tape cutting line in the wafer cut line formation process, the laser is irradiated to the almost same depth position of the wafer, and the modified portion of the same depth is applied to the wafer surface side. The wafer cutting dividing line can be formed on the front surface side of the wafer. As a result, the wafer can be cleaved (divided) with high precision along the wafer cutting dividing line.

  According to an eighth aspect of the present invention, in the method according to the fifth, sixth, or seventh aspect, the front surface side of the wafer is set downward, and the laser by the laser irradiation unit is set from the lower side of the wafer. A semiconductor manufacturing method for irradiation is provided.

  According to this method, the laser irradiation port by the laser irradiation means can be arranged on the lower side. As a result, when performing a cleaning operation or the like, it is possible to easily perform the operation or the like with a natural posture so as not to impose an unreasonable posture on the operator even when viewed from the viewpoint and the work. Further, for example, a measure for reducing the number of cleanings by providing a blow or the like can be easily introduced.

  According to the present invention, it is possible to divide a wafer into small pieces easily and at low cost with less influence on quality. In addition, even if the wafer diameter is increased, dicing can be performed without using a large-diameter dicer by making the wafer smaller, thereby reducing cost and time. Become.

1 is a schematic configuration block diagram of a semiconductor manufacturing apparatus in an embodiment of the present invention. The figure explaining the implementation procedure of the semiconductor manufacturing method in embodiment of this invention. The figure explaining schematic structure of the back grinding apparatus and wafer conveyance means of the semiconductor manufacturing apparatus in embodiment of this invention. The figure explaining schematic structure of the alignment part of the semiconductor manufacturing apparatus in embodiment of this invention. It is a figure explaining the process of the tape parting line by the laser unit of the semiconductor manufacturing apparatus in embodiment of this invention, (a) is the side view, (b) is the top view. It is a figure explaining the process of the dividing line for wafer cutting by the laser unit of the semiconductor manufacturing apparatus in embodiment of this invention, (a) is the side view, (b) is the top view. It is a figure explaining the structure of the separate table of the semiconductor manufacturing apparatus in embodiment of this invention, (a) is the side view, (b) is the top view. It is a figure explaining the method of dividing | segmenting the wafer using the separate table of the semiconductor manufacturing apparatus in embodiment of this invention, (a) is a side view before a division | segmentation, (b) is a side view at the time of a division | segmentation, (c) is An explanatory view in the case of dividing the wafer in half along the X axis, (d) is an explanatory view in the case of dividing the wafer into a quarter along the Y axis. The figure explaining the structure of the separate table of the semiconductor manufacturing apparatus in embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the structure of the separate table of the semiconductor manufacturing apparatus in embodiment of this invention, (a) is a figure which shows the state which the separate table faces the upper side, (b) is a separate table which faces the lower side. The figure which shows a state, (c) demonstrates the motion of a division | segmentation separate table. The figure explaining the state by which a ring frame is arrange | positioned in the wafer mounting means of the semiconductor manufacturing apparatus in embodiment of this invention. The figure explaining the structure which presses a dicing tape toward a wafer with a balloon in the wafer mounting means of the semiconductor manufacturing apparatus in embodiment of this invention. The figure explaining the structure and operation | movement of the back grinding tape peeling part of the semiconductor manufacturing apparatus in embodiment of this invention. The figure explaining the state by which a ring frame is accommodated in the frame carrier of the semiconductor manufacturing apparatus in embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the state by which the fragmented wafer in embodiment of this invention was mounted in the ring frame, (a)-(d) has shown the state in which each different fragmented wafer is mounted. FIG. 4E shows the wafer before being cut into pieces.

  The present invention reduces the influence on the wafer quality, can cut the wafer easily and at low cost, and does not use a dicer corresponding to the large diameter even if the diameter of the wafer is large. In order to achieve the purpose of providing a semiconductor manufacturing method that enables dicing even if the semiconductor is divided into a plurality of wafers that have been ground on the back side by attaching a back grinding tape to the front side In the manufacturing method, the ablation processing step of irradiating the back grinding tape with a laser to divide the back grinding tape into a plurality of pieces, and the laser cutting of the back grinding tape with respect to the surface of the wafer A wafer that irradiates along a line and forms a wafer-cutting dividing line on the wafer And Ttorain forming process was achieved by having to include the a wafer dividing step for dividing into a plurality of small pieces by the wafer is broken the wafer along the wafer cutting dividing line.

  In addition, the present invention makes it possible to cut the wafer easily and at a low cost with less influence on the quality of the wafer, and even if the diameter of the wafer is increased, a dicer corresponding to the increased diameter is used. In order to achieve the purpose of providing a semiconductor manufacturing apparatus that enables dicing even if not, a semiconductor that divides a wafer that has been ground on the back side by pasting a back grinding tape on the front side into a plurality of pieces In the manufacturing apparatus, the apparatus has laser irradiation means, and the laser irradiation means irradiates the back grinding tape on the wafer with laser to divide the back grinding tape into a plurality of pieces, and the back grinding A laser is irradiated on the surface of the wafer along the cut line of the tape to irradiate the wafer to the wafer. Comprising a laser irradiation unit for forming a parting line for bets were realized manner.

  Hereinafter, an embodiment of the present invention will be described in detail based on a preferred example shown in the accompanying drawings.

  1 to 15 show an embodiment of a semiconductor manufacturing apparatus according to the present invention. FIG. 1 is a schematic block diagram of the semiconductor manufacturing apparatus, FIG. 2 is a manufacturing process diagram, and FIGS. 3 to 15 are manufacturing processes. It is explanatory drawing for demonstrating the structure and processing method of each process part in FIG.

  As shown in FIG. 1, the semiconductor manufacturing apparatus 10 includes a control unit 11, a back grinding apparatus 12, an alignment unit 13, a laser irradiation unit 14, a wafer dividing unit 15, a wafer turnover holding unit 16, and a ring. A frame placement unit 17, a wafer mount unit 18, a back grinding tape peeling unit 19, a wafer transfer unit 21, and a frame carrier 22 are provided.

  The said control part 11 is a computer which bears the central processing function of the semiconductor manufacturing apparatus 10, for example, Comprising: Various processes are performed. The control unit 11 is provided with a memory 111 in which various processing programs are stored.

  As shown in FIGS. 3 to 11, the wafer transfer means 21 includes a transfer chuck 211 for sucking and holding the back surface of the wafer W by suction and transferring the wafer W to each processing unit in order. . The transfer chuck 211 is provided with a number of suction holes on the entire suction surface, and the entire back surface of the wafer W is vacuum-sucked and held by the plurality of holes, thereby correcting the warpage of the wafer W and flattening it. It has a function of holding the degree of 5 μm or less. Further, the main surface of the wafer W is protected by attaching an extendable (stretchable) back grinding tape GT made of a resin tape or the like to the surface (main surface).

  The back grinding apparatus 12 has a vacuum chuck table 121 for holding the wafer W as shown in FIG. In the back grinding apparatus 12, the wafer W in the back grinding apparatus 12 is placed on the vacuum chuck table 121 with the main surface side facing down, and the wafer W is held by the vacuum chuck table 121. The back side can be ground and thinned.

  The alignment unit 13 includes an alignment unit (for example, an alignment camera) 131 as shown in FIG. The alignment unit 13 finishes the grinding in the back grinding apparatus 12, and is aligned with the wafer W that is chucked by the transfer chuck 211 from the back grinding apparatus 12 and taken out with the main surface facing downward. Is performed over the back grinding tape GT by the alignment unit 131. The alignment unit 131 is movable in the XX direction and the YY direction substantially parallel to the wafer W. The alignment includes, for example, the center position of the wafer W, theta direction, scribe line, cut position, etc., and the alignment is performed by using a general method, for example, center position alignment from outer shape recognition, by recognizing two points. Scribe line and cut position alignment.

  As shown in FIGS. 5 and 6, the laser irradiation unit 14 includes a laser unit 141 as laser irradiation means. The laser unit 141 is formed so as to be able to irradiate a laser toward the main surface of the wafer W from an irradiation port arranged on the lower side with respect to the main surface of the wafer W. That is, the main surface of the wafer W that is taken out by the transfer chuck 211 with the main surface facing downward and set with the main surface facing down is formed so as to be able to irradiate the laser. Therefore, here, the process can be efficiently performed without performing the reversing operation of the wafer W or the like, and the operator is forced to take an uncomfortable posture when performing the cleaning operation of the laser irradiation port in the laser unit 141. Therefore, the worker can easily carry out the operation in a natural posture. Further, for example, measures such as providing a blow to reduce the number of cleanings can be easily introduced. In the laser irradiation here, first, as shown in FIG. 5, a laser having a short wavelength of about 266 nm is irradiated toward the back grinding tape GT attached to the main surface of the wafer W. The tape dividing lines L1X and L1Y are formed on the main surface of the wafer W. Subsequently, as shown in FIG. 6, a laser having a short wavelength of about 266 nm is irradiated on the main surface of the wafer W along the tape dividing lines L1X and L1Y. Processing is performed in two stages so as to provide wafer cutting dividing lines L2X and L2Y in which a modified layer of about 50 μm is formed in a V-groove shape.

  As described above, when the back grinding tape GT is first irradiated with a laser having a short wavelength of about 266 nm, the back grinding tape GT is less affected by heat, and at the same time, the wafer W is not melted. Thus, only the back grinding tape GT can be divided. In addition, after dividing the back grinding tape GT, a gap is formed in the tape dividing lines L1X and L1Y. On the main surface of the wafer W corresponding to the tape dividing lines L1X and L1Y of the back grinding tape GT, The back grinding tape GT is almost removed from the main surface of W, and the main surface of the wafer W is exposed. Therefore, when the laser is irradiated along the tape dividing lines L1X and L1Y, the main surface of the wafer W is irradiated with the laser having substantially the same intensity within the wafer W without being affected by the back grinding tape GT. The modified layer having substantially uniform fragility inside W is formed as wafer-cutting dividing lines L2X and L2Y over a depth of about 5 to 50 μm from the surface layer, for example. Thereby, accurate cleaving of the wafer W becomes possible.

  More specifically, the laser unit 141 is movable in the XX direction and the YY direction substantially parallel to the wafer W. In this embodiment, as shown in FIG. 5B, the laser beam is crossed in the XX direction and the YY direction so that the wafer W is divided into approximately four equal parts with respect to the back grinding tape GT. The back grinding tape GT is provided with a tape dividing line L1X and a tape dividing line L1Y that intersects the tape dividing line L1X at right angles to divide the back grinding tape GT into four. It can be done. Further, as shown in FIG. 6B, the laser is irradiated in a cross shape in the XX direction and the YY direction along the tape dividing lines L1X and L1Y formed by dividing the back grinding tape GT, respectively. Then, a wafer cutting dividing line L2X and a wafer W cutting dividing line L2Y that intersects the wafer W cutting dividing line L2X at right angles can be provided inside the wafer W, respectively.

In the present embodiment, the reason for performing the cutting using the laser instead of the blade in the process of cutting the wafer W is based on the following (1) to (3).
(1) Since the processing unit of the laser is very small, the back grinding tape GT and the wafer W can be processed efficiently. On the other hand, since the blade cuts the back grinding tape GT and the wafer W at the same time, there is a concern about the influence on the quality.
(2) Since lasers can be dry-processed, they are not subject to processing environment restrictions. On the other hand, since the blade requires water, it is necessary to prepare an environment (function) in which the water is used.
(3) Although it is necessary to select a blade according to the object to be processed, it takes time. However, since the output of the laser can be changed by a parameter, labor can be saved.

  As shown in FIGS. 7 to 10, the wafer dividing unit 15 is provided with four divided separation table units 151 a, 151 b, 151 c, and 151 d respectively corresponding to the equally divided portions of the wafer W. A table 151 is provided. Each of the divided separate table portions 151a to 151d is independently “a suction mechanism 152” that makes it possible to vacuum-suck the wafer W, and one side of the divided separate table portions 151a to 151d is placed below or above the other divided separate table portions. For example, the “tilt operation mechanism 153” that allows the adjacent divided separate table portions to be moved by 5 to 10 mm to be bent and inclined in a mountain shape or a valley shape, and other adjacent separate separate table portions, respectively. As shown in FIG. 10 (c), an “X / Y axis operation mechanism 154” that enables movement of about 5 to 10 mm in the X and Y axis directions (left and right, front and rear direction) and other adjacent divided separators. It has a “Z-axis operation mechanism 155” that can move about 5 to 10 mm in the Z-axis direction (vertical direction) relative to the table. Note that each of the tilting mechanism 153, the X / Y axis operating mechanism 154, and the Z axis operating mechanism 155 is movable by using, for example, a reciprocating operation using a ball screw or a reciprocating operation using an air cylinder. FIG. 10C shows a state in which each of the divided separate table portions 151a to 151d can reciprocate in the X and Y directions.

  Furthermore, in each of the separate separation table sections 151a, 151b, 151c, 151d, the shaft 156a is fixed in the Z-axis direction (vertical direction) in FIG. 10, and the shafts 156b, 156c are movable in the Z-axis direction. . When the shafts 156b and 156c move independently in the Z-axis direction, the divided separate table portions 151a to 151d can be tilted or moved in the vertical direction, and can be bent and tilted into the mountain shape or the valley shape.

  The configuration of the separate table 151 will be described in more detail. In the separate table 151, as shown in FIGS. 8C and 8D, the wafer cutting division lines L2X and L2Y are formed by the laser unit 141. The center of the wafer W is aligned with the center of the separation table 151, and the wafer cutting division lines L2X and L2Y are aligned with the folding lines 151X and 151Y, respectively, and the suction mechanism 152 is vacuum suctioned. Then, the wafer W can be held on the separate table 151.

Further, with the wafer W set on the separate table 151, the tilt operation mechanism 153 is driven to move one side (or both sides) of the divided separate table portions 151c and 151d as shown in FIG. 8B. When the adjacent divided table portions 151a and 151b are bent in a chevron shape by inclining, for example, about 5 to 10 mm in the Z-axis direction (up or down direction), the wafer W is cut into a wafer as shown in FIG. It is divided along the dividing line 151X, and can be divided into two wafer halves WA and WB. Further, the tilting operation mechanism 153 is driven in the same fixed set state, and as shown in FIG. 8B, one side (or both sides) of the divided separate table portions 151a and 151d is adjacent to the divided separate. If the table portions 151b and 151c are bent at an angle of, for example, about 5 to 10 mm in the Z-axis direction (up or down), the wafer W is cleaved along the wafer cutting dividing line 151Y shown in FIG. Thus, the wafer can be divided into four pieces of wafers Wa, Wb, Wc, and Wd.

  As shown in FIG. 10, the wafer turnover holding means 16 is provided in the wafer dividing section 15, and a separate table 151 configured to hold the wafers Wa, Wb, Wc, Wd that has been cut into pieces is 180 °. A rotating shaft 161 that can be turned over and a motor 162 (see FIG. 1) that can drive the rotating shaft 161 are provided.

  Then, as shown in FIGS. 9 and 10, the wafer turnover holding means 16 turns the separation table 151 180 degrees from the state of FIG. 10A together with the wafers Wa, Wb, Wc, and Wd which are made into small pieces. 9 and the control shown in FIG. 10B. That is, in the state shown in FIG. 9 and FIG. 10B, the main surface on which the back grinding tape GT is attached is on the upper side and the back surface is on the lower side, respectively, and the wafers Wa, Wb, Wc and Wd are held in the separate table 151.

  As shown in FIG. 11, the ring frame arrangement means 17 has a frame-shaped ring frame (also referred to as “wafer frame”) 171 to which a dicing tape DT that is an adhesive tape for holding the wafer W is attached. . The inner diameter of the ring frame 171 is set to be smaller than the outer diameter of the wafer W before being fragmented and larger than the outer diameters of the wafers Wa, Wb, Wc, Wd that have been fragmented. The small wafers Wa, Wb, Wc, and Wd can be set on the dicing tape DT attached to the ring frame 171. More specifically, the ring frame 171 here is a ring frame having an inner diameter of 350 mm, for example, for an outer diameter of 300 mm of the wafer W, and the outer diameter of the wafer W before being cut into pieces is 450 mm. Therefore, the ring frame 171 for an outer diameter of 300 mm cannot use the wafer W having an outer diameter of 450 mm as it is. However, since the wafer W having an outer diameter of 450 mm has already been divided into four pieces, the ring frame 171 for the outer diameter of 300 mm can be used even in the case of the wafer W having a diameter of 450 mm.

  Then, as shown in FIG. 11, the ring frame disposing means 17 moves the ring frame 171 with the dicing tape DT attached under the wafers Wa, Wb, Wc, Wd into small pieces. And the centers of the selected wafers Wa, Wb, Wc, and Wd are substantially aligned with each other so that they can be moved in order.

  As shown in FIG. 12, the wafer mounting means 18 has a balloon 181 that is arranged in a state of being inflated (or inflated afterwards) below the dicing tape DT of the ring frame 171. The balloon 181 is formed as a flexible bag made of silicon rubber or the like, and air or water is put into the bag to be inflated. Then, the balloon 181 is sequentially moved down to any one of the wafers Wa, Wb, Wc, and Wd that have been fragmented together with the ring frame 171 in the ring frame disposing means 17, and then air is introduced and gradually introduced. The dicing tape DT is gradually pushed up along with the swelling, and is pressed against the lower surfaces (back surfaces) of the corresponding wafers Wa, Wb, Wc, Wd, respectively, through the dicing tape DT. It has become. Also, one of the wafers Wa, Wb, Wc, Wd, which has been cut into pieces on the dicing tape DT by pressing through the dicing tape DT, is attached with the adhesive force of the dicing tape DT, and is cut into pieces on the ring frame 171. One of the wafers Wa, Wb, Wc, Wd that has been formed can be mounted. In addition, when the dicing tape DT is pressed against any one of the wafers Wa, Wb, Wc, and Wd that have been cut into pieces, pressure is also applied from the wafer W side in order to more reliably attach the dicing tape DT.

  Here, when the balloon 181 that was gradually inflated by introducing air was gradually pressed through the dicing tape DT onto the lower surfaces (back surface) of the wafers Wa, Wb, Wc, and Wd that were fragmented, the balloon 181 was inflated. The contact of the balloon 181 with the dicing tape DT comes in contact with the dicing tape DT so as to gradually spread outward from the center (center) position of the dicing tape DT. Therefore, the dicing tape DT contacting the lower surface (back surface) of the fragmented wafer (any one of Wa, Wb, Wc, Wd) is also one of the fragmented wafers (Wa, Wb, Wc, Wd). One) touches so that it gradually expands outward from the center position (center). Thereby, the air existing between the dicing tape DT and the fragmented wafer (any one of Wa, Wb, Wc, and Wd) is pushed outward with contact. The fragmented wafer (any one of Wa, Wb, Wc, and Wd) is in close contact with the dicing tape DT without any air interposed therebetween, and is securely adhered and held on the ring frame 171. Mounted in the state. Further, the ring frame 171 mounted with the wafer (Wa, Wb, Wc, Wd) thus fragmented is transported to the back grinding tape peeling unit 19 by the wafer transport means 21. It is like that. On the other hand, the balloon 118 after the dicing tape DT is gradually pushed up and any one of the wafers (Wa, Wb, Wc, Wd) and the dicing tape DT are attached to each other is introduced into the inside. When the air is removed, the air is instantly shrunk downward and away from the dicing tape DT.

  As shown in FIG. 13, the back grinding tape peeling part 19 has been mounted on a wafer (Wa, Wb, Wc, Wd) that has been cut into small pieces, and is transferred by the wafer transfer means 21. A suction stage 191 for positioning the incoming ring frame 171 by vacuum suction holding, and a piece of wafer (Wa, Wb, Wc, Wd) on the ring frame 171 sucked and held by the suction stage 191 1) a back grinding tape peeling means 192 for attaching a peeling tape RT on the back grinding tape GT affixed to the main surface, and lifting and peeling the back grinding tape GT together with the peeling tape RT; Is provided. Then, the ring frame 171 mounted with the wafer (one of Wa, Wb, Wc, Wd) from which the back grinding tape GT has been peeled in this way is transferred to the frame carrier 22 by the wafer transfer means 21. The frame carrier 22 is stored and stored.

  The frame carrier 22 is mounted with a ring frame 171 mounted with a wafer (any one of Wa, Wb, Wc, Wd) peeled off from the back grinding tape GT, which is carried by the wafer carrying means 21. A plurality of shelves 221 are stored and stored.

  FIG. 2 is a process diagram showing an example of a processing procedure in the semiconductor manufacturing apparatus 10 described above. Next, an example of a processing procedure in the semiconductor manufacturing apparatus 10 will be described with reference to FIGS. 1 and 3 to 14 in accordance with the process chart shown in FIG.

  The process diagram shown in FIG. 2 shows that a wafer W having an outer diameter of 450 mm that has been ground by the back grinding apparatus 12 is taken out from the back grinding apparatus 12 and a ring frame 171 having an inner diameter of 350 mm that is smaller than the outer diameter of the wafer W. The process until mounting is shown. Also, the process is roughly divided into the processing order: alignment process (A), ablation process (B), wafer cut line formation process (C), wafer splitting process (D), wafer turning over process (E), wafer mounting process (F), back grinding tape peeling step (G). In this example, a case where a wafer W having an outer diameter of 450 mm is mounted on a ring frame 171 having an inner diameter of 350 mm smaller than the outer diameter of the wafer W will be described. However, the dimensions are not limited to this. However, the present invention can be applied to a case where a wafer W having a large outer diameter is mounted on a ring frame 171 having a small inner diameter to enable dicing.

  First, in the alignment step (A), as shown in FIG. 3, the back grinding is finished in a state where the back grinding tape GT is attached to the main surface (front surface) side in the back grinding device 12. The wafer W thinned in this manner is vacuum-sucked and held by the transfer chuck 211 of the wafer transfer means 21 and taken out from the back grinding apparatus 12. The wafer W here is taken out with the main surface side to which the back grinding tape GT is attached facing down. At that time, the entire back surface of the wafer W is vacuum-sucked by the transfer chuck 211, whereby the warpage of the wafer W is corrected and flattened. Further, as shown in FIG. 4, an alignment unit (alignment camera) 131 is directed from the lower side to the main surface of the wafer W held flat by the transfer chuck 211 and is passed over the back grinding tape GT. Perform alignment.

  In the alignment step (A), when the back grinding tape GT has poor visibility and alignment through the back grinding tape GT is impossible, the wafer W after grinding is transferred. Prior to suction by the chuck 211, for example, an infrared camera is used to image a ground surface (polished surface), alignment is performed, and the data is stored in the memory 111. After the alignment, the wafer W can be sucked by the transfer chuck 211 and transferred to the next process, and can be changed to a means for reading out alignment data at the time of separate use.

  In the ablation processing step (B), as shown in FIG. 5, from the lower side of the wafer W toward the surface not attracted to the transfer chuck 211, that is, the main surface side to which the back grinding tape GT is attached, A laser having a wavelength of 266 nm is irradiated from an irradiation port (not shown) facing the upper side of the laser unit 141 disposed on the lower side of the wafer W, and only the portion of the back grinding tape GT irradiated with the laser is melted. Ablation processing to cut. In this ablation processing, the laser is cruciform in the XX and YY directions with respect to the back grinding tape GT so as to divide the wafer W into four equal parts with reference to the alignment position in the alignment step (A). 5B, a tape dividing line L1X and a tape dividing line L1Y that intersects the tape dividing line L1X at right angles are provided on the back grinding tape GT. Further, a gap is made in the portion where the tape dividing lines L1X and L1Y are provided by forming the tape dividing lines L1X and L1Y.

  In the wafer cut line forming step (C), as shown in FIG. 6, as in the case of the ablation processing step (B), the laser unit 141 disposed below the wafer W is directed upward. The laser having a wavelength of 266 nm is irradiated along the tape dividing line L1X and the tape dividing line L1Y from the lower side of the wafer W, that is, from the lower side of the wafer W toward the main surface side of the wafer W. Wafer cut dividing line L2X and wafer W cutting dividing line L2X intersecting at right angles with a modified layer having a V-shaped groove with a depth of about 5 to 50 μm inside. L2Y is provided in a cross shape as shown in FIG.

  In addition, the wafer W that has finished the processing in the ablation processing step (B) and the wafer cut line formation step (C) is held by the transfer chuck 211 as shown in FIG. It is transferred to the dividing step (D) and transferred onto the separation table 151 of the wafer dividing unit 15. Then, as shown in FIG. 8A, the wafer W transferred to the wafer dividing step (D) has its main surface side (back grinding tape GT side) facing downward, that is, the back grinding tape is The center of the wafer W is aligned with the center of the wafer dividing section 15 with the back side not attached on the upper side, and as shown in FIGS. 8 (c) and 8 (d), the wafers are cut along the folding lines 151X and 151Y, respectively. The divided lines L2X and L2Y are arranged on the separate table 151 together.

  In the wafer dividing step (D), the wafer W placed on the separation table 151 is held by vacuum suction of the suction mechanism 152. Next, the tilting operation mechanism 153 is driven, and as shown in FIGS. 8B and 8C, one side of the divided separate table units 151a and 151b is moved with respect to the adjacent divided separate table units 151c and 151d. Then, it is bent in a chevron by inclining about 5 to 10 mm in the Z-axis direction (upward). By this bending, the wafer W is cleaved along the wafer cutting dividing line 151X and divided into two wafer halves WA and WB. Further, similarly, the tilting operation mechanism 153 is driven in the fixed set state, and as shown in FIGS. 8B and 8D, one side of the divided separate table units 151a and 151d is adjacent to the divided separate table. For example, the portions 151b and 151c are bent at an angle of about 5 to 10 mm in the Z-axis direction (upward). By this bending, the wafer W is further cleaved along the wafer cutting dividing line 151Y and divided into four pieces of wafers Wa, Wb, Wc, and Wd.

  When the wafer division in the wafer dividing step (D) is completed, the process proceeds to the wafer turning over step (E). In the wafer dividing step (D), the motor 162 is driven to rotate the rotating shaft 161 by 180 °. The rotation of the rotating shaft 161 causes the separate table 151 holding the wafers Wa, Wb, Wc, Wd, which have been cut into pieces, to be vacuum-sucked and rotated 180 ° together with the rotating shaft 161. ) And flipped 180 °. Further, by turning the separate table 151 upside down, the four wafers Wa, Wb, Wc, and Wd that are attracted and held on the separate table 151 are respectively arranged such that the main surface side (back grinding tape GT side) is the upper side, It is held with the back side facing down. Thereafter, the process proceeds to the wafer mounting process (F).

  In the wafer mounting step (F), as shown in FIG. 11, four pieces of wafers (Wa, Wb, Wc, Wd) that are turned upside down and held by a separate table 151 in the wafer turning over step (E) are held. The ring frame 171 with the dicing tape DT is moved to the lower side of any one of the wafers. Here, the ring frame 171 has an inner diameter of 3500 mm, but is larger than the maximum outer diameter of the wafer (Wa, Wb, Wc, Wd) that has already been divided into four. In the following description, a wafer (Wa, Wb, Wc, Wd) selected for simplification will be described as a wafer Wd. Then, the center of the ring frame 171 is made to substantially coincide with the center of the selected wafer Wd.

  At almost the same time, as shown in FIG. 12, a balloon 181 is disposed below the ring frame 171, and air is introduced into the balloon 181 so that the balloon 181 is gradually inflated. The balloon 181 gradually pushes up the dicing tape DT in conjunction with the expansion of the balloon 181, and the balloon 181 is gradually pressed over the dicing tape DT to the lower surface (back surface) of the selected wafer Wd. Then, by pressing the balloon 181 through the dicing tape DT, the back surface of the selected wafer Wd is affixed to the dicing tape DT by the adhesive force of the dicing tape dT, and the wafer Wd faces the main surface upward. And mounted on the ring frame 171. When the mounting is completed, the air introduced into the balloon 118 is removed, and the balloon 118 is instantaneously contracted downward and separated from the dicing tape DT. Further, the vacuum suction to the wafer Wd by the divided separate table portion 151a corresponding to the wafer Wd mounted on the ring frame 171 is released. Then, the selected wafer Wd is transferred to the back grinding tape peeling step (G) together with the ring frame 171 by the transfer of the wafer transfer means 21.

  In the back grinding tape peeling process (G), the wafer Wd is mounted, and the ring frame 171 conveyed from the wafer mounting process (F) is placed on the suction stage. Then, as shown in FIG. 13, the lower surface of the dicing tape DT is vacuum-sucked and held by the suction stage 191. Thereafter, the release tape RT is attached by the back grinding tape peeling means 192 on the back grinding tape GT attached to the main surface of the ring frame 171. Thereafter, the back grinding tape GT is lifted together with the peeling tape RT and peeled off from the wafer Wd. When the back grinding tape GT is peeled off, the ring frame 171 is unsucked and held by the suction stage 191 and further transported to the frame carrier 22 by the wafer transport means 21. The frame carrier 22 is stored and stored in a shelf 221 as shown in FIG. Thereby, a series of processing operations are completed. Next, the remaining fragmented wafers (Wa, Wb, Wc) are processed in the same manner, stored in the frame carrier 22 and stored.

  FIG. 15 shows a state where one wafer W is divided into four pieces of wafers (Wa, Wb, Wc, Wd) and mounted on each ring frame 171. 15A shows a state where the fragmented wafer Wa is mounted on the ring frame 171, FIG. 15B shows a state where the fragmented wafer Wb is mounted on the ring frame 171, and FIG. 15C. Is a state where the fragmented wafer Wc is mounted on the ring frame 171, (d) indicates a state where the fragmented wafer Wd is mounted on the ring frame 171, and (e) is fragmented. The previous wafer W is shown.

  As described above, according to the present invention, even if the diameter of the wafer W is larger than the conventional 300 mm, for example, 400 mm, for example, 400 mm, the dicing process is performed using the conventional ring frame and dicer for 300 mm. Therefore, cost and time can be reduced.

  Further, when the wafer W is divided, for example, the back grinding tape GT is irradiated with a laser having a short wavelength of about 266 nm to divide the back grinding tape GT, and then the wafer W is similarly short with a wavelength of about 266 nm. The wafer cutting division lines L2X and L2Y are formed by irradiating the wavelength laser, and the wafer W is cleaved along the wafer cutting division lines L2X and L2Y. ) To make small pieces.

  In the above-described embodiment, the case where the wafer W having an outer diameter of 400 mm is divided into four equal parts and mounted on the ring frame 171 for 300 mm has been described, but the 400 mm wafer W is radially divided into three equal parts from the approximate center, etc. Then, the wafer may be divided into smaller wafers whose outer diameter is smaller than 300 mm.

  The present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

  Although the present invention has been described with respect to mounting a semiconductor wafer on a ring frame, the present invention can also be applied to a dicing apparatus that cleaves (divides) a workpiece such as a semiconductor wafer and electronic component materials other than the semiconductor wafer into individual chips.

DESCRIPTION OF SYMBOLS 10 Semiconductor manufacturing apparatus 11 Control part 111 Memory 12 Back grinding apparatus 121 Vacuum chuck table 13 Alignment part 131 Alignment unit 14 Laser irradiation part 141 Laser unit (laser irradiation means)
15 Wafer dividing section 151 Separate tables 151 a to 151 d Dividing separate table section 151 X Bending line 151 Y Bending line 152 Suction mechanism 153 Tilt operating mechanism 154 X / Y axis operating mechanism 155 Z axis operating mechanism 16 Wafer inversion holding means 161 Rotating shaft 162 Motor 17 Ring frame placement means 171 Ring frame 18 Wafer mounting means 181 Balloon 19 Back grinding tape peeling part 191 Suction stage 192 Back grinding tape peeling means 21 Wafer transfer means 211 Transfer chuck 22 Frame carrier 221 Shelf DT Dicing tape GT Back grinding tape RT Release tape W Wafer WA, WB Wafer half Wa, Wb, Wc, Wd 151Y fold line L2X, L2Y wafer cut for dividing line L1X, L1Y tape cut line

Claims (8)

In a semiconductor manufacturing apparatus that divides a wafer that has been ground on the back side by pasting back grinding tape on the front side, into a plurality of pieces,
A laser irradiating means for irradiating the back grinding tape on the wafer with a laser by the laser irradiating means to divide the back grinding tape into a plurality of pieces, and the back grinding tape is divided; A semiconductor manufacturing apparatus, comprising: a laser irradiation unit configured to irradiate a surface of the wafer with a laser along a line and form a dividing line for wafer cutting on the wafer.   The semiconductor manufacturing apparatus according to claim 1, wherein the tape dividing line and the wafer cutting dividing line are formed in a substantially cross shape through substantially the center of the wafer.   The semiconductor manufacturing apparatus according to claim 1, wherein the laser irradiation unit irradiates the back grinding tape and the wafer with a laser having a short wavelength.   4. The semiconductor manufacturing apparatus according to claim 1, wherein the wafer is set with the surface side facing downward, and the laser irradiation means irradiates the laser from the lower side of the wafer. . In the semiconductor manufacturing method of dividing the wafer after pasting the back grinding by attaching the back grinding tape to the front surface side,
Ablation processing step of irradiating the back grinding tape with a laser and dividing the back grinding tape into at least three or more,
A wafer cut line forming step of irradiating the surface of the wafer with a laser along a tape cutting line of the back grinding tape to form a wafer cut dividing line on the wafer;
A wafer dividing step of breaking the wafer along the wafer cutting dividing line and dividing the wafer into a plurality of small wafers,
A method of manufacturing a semiconductor.   6. The semiconductor manufacturing method according to claim 5, wherein the tape dividing line and the wafer cutting dividing line are formed in a substantially cross shape through substantially the center of the wafer.   7. The method of manufacturing a semiconductor according to claim 5, wherein the laser in the ablation processing step and the laser in the wafer cut line forming step have a short wavelength. 8. The method of manufacturing a semiconductor according to claim 5, wherein the front surface side of the wafer is set downward and the laser by the laser irradiation unit is irradiated from the lower side of the wafer. .

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