JP2008192762A - Method of manufacturing semiconductor device, and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a manufacturing cost of a semiconductor device by shortening the processing time and improving the workability. <P>SOLUTION: A wafer 1 is formed with a plurality of element portions 3 demarcated by scribe lines 2 in an ordinary wafer process (a semiconductor manufacturing process). Then, in a through portion formation process, through portions 5 which penetrate the wafer 1 from the front to rear face are formed in regions including intersecting points P between the scribe lines 2 except for the plurality of element portions 3 using chemical machining and physical machining. Thereafter, in a dicing process, the wafer 1 is diced along the scribe lines 2 into individual semiconductor devices 4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a manufacturing method of a so-called chip size package (CSP) type semiconductor device for forming a circular or polygonal semiconductor device, and the semiconductor device.

  A conventional semiconductor device is divided into quadrilateral pieces by dicing, mounted on a lead frame, and packaged. However, in recent years, semiconductor devices such as sensors and ICs such as camera modules of mobile phones have been desired to be small and thin, and CSP type semiconductor devices in which the shape of the semiconductor device itself is the package size have become mainstream. It's getting on. Further, needs in the field of endoscope and the like are demanded for a semiconductor device having a small projected area as viewed from the top rather than being made thinner. This is because, when a semiconductor device is mounted in a cylindrical tube, the projected area in the radial direction can be effectively used by making it circular or polygonal.

As a technique related to a polygonal semiconductor device and a manufacturing method thereof, for example, in Japanese Patent Application Laid-Open No. 2004-79667, a corner of a semiconductor device is prevented in order to prevent damage to a corner of the semiconductor device due to stress concentration in a molding process. A technique is disclosed in which stress is relieved by chamfering a portion. Specifically, there are a method of chamfering an individual rectangular semiconductor device by physical processing, or a method of dividing a semiconductor device into a polygonal shape or a circular shape by laser irradiation or etching from a wafer. It is disclosed.
JP 2004-79667 A

  However, the method of chamfering by physical processing disclosed in Patent Document 1 described above has a problem that processing time becomes long because physical additional processing is performed. Furthermore, this additional processing requires processing accuracy in order to maintain the shape of the semiconductor device, and there is a possibility that complicated processing equipment or the like must be prepared. Further, in the method of separating a semiconductor device by laser irradiation disclosed in Patent Document 1 described above, it is necessary to cut all the isolation regions of the semiconductor device with laser light, which also increases the processing time. There is. Further, in this method of dividing a semiconductor device by laser irradiation, it may be difficult to cut depending on the crystal direction of the wafer. Furthermore, the method disclosed in Patent Document 1 described above that separates a semiconductor device by etching has a problem in that workability deteriorates because the semiconductor device is separated when the semiconductor device is separated by etching.

  The present invention has been made in view of the above circumstances, and provides a semiconductor device manufacturing method and a semiconductor device capable of shortening the processing time of the semiconductor device, improving workability, and reducing the manufacturing cost. The purpose is to do.

  In the method of manufacturing a semiconductor device according to the present invention, a penetrating portion penetrating the wafer is formed in a region including an intersection of the scribe lines other than the element portion of a wafer that is partitioned by a scribe line to form an element portion. A semiconductor device according to the present invention is manufactured by this manufacturing method, comprising: a through portion forming step; and a dicing step of dicing the wafer on which the through portion is formed into individual semiconductor devices. The

  According to the method for manufacturing a semiconductor device and the semiconductor device according to the present invention, it is possible to shorten the processing time of the semiconductor device, improve the workability, and reduce the manufacturing cost.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show a first embodiment of the present invention, FIG. 1 is a front view of a wafer on which an element portion is formed, FIG. 2 is a front view of a wafer on which a through portion is formed, and FIG. 3 is an enlarged view of the through portion. FIG. 4 is an explanatory view of a semiconductor device diced by a scribe line.

  In FIG. 1, reference numeral 1 denotes a wafer on which a plurality of element parts 3 partitioned by a scribe line 2 are formed in a normal wafer process (semiconductor manufacturing process). Through the dicing process, a plurality of semiconductor devices 4 having a polygonal planar structure (in the first embodiment, an octagon is taken as an example) shown in FIG. 4 are obtained.

First, a penetration part formation process is demonstrated.
As shown in FIG. 2 and FIG. 3, the through-hole forming process is performed by placing the wafer 1 from the surface in a region including the intersection P between the scribe lines 2 other than the plurality of element portions 3 with respect to the wafer 1. This is a process of forming the penetrating part 5 penetrating to the back surface.

  The through portion 5 is formed using chemical processing such as wet etching or dry etching, or physical processing such as sand blasting, laser, or water jet.

  Specifically, a protective film such as a film, a resist, or a Si02 thin film is formed on the surface other than the penetrating part 5, and processing such as etching is performed.

  When wet anisotropic etching that exposes the <111> plane of a crystal plane with a slow etching rate, such as a potassium hydroxide (KOH) or tetramethylammonium hydroxide (TMAH) solution, is used to form the penetrating part 5. When the wafer 1 having a <100> plane and the orientation flat (hereinafter abbreviated as orientation flat OF) direction <110> is used, each penetrating portion as shown in FIG. The penetrating part 5 can be formed in a layout in which the four sides of 5 are inclined 45 degrees with respect to the orientation flat OF.

  Further, when the wafer 1 having the <100> surface and the orientation flat OF direction <100> is used, the layout of the elements 3 on the wafer 1 is rotated by 45 degrees as a whole. If formed, the through portions 5 can be formed in a layout in which the four sides of each through portion 5 are perpendicular or parallel to the orientation flat OF as shown in FIG.

  On the other hand, when the penetrating part 5 is formed by chemical processing by dry etching or physical processing such as sand blasting or laser, the penetrating part 5 is formed regardless of the plane orientation of the wafer 1 or the orientation flat OF direction. The shape can be formed into an arbitrary shape such as a circular shape or a polygonal shape.

  In the first embodiment, since the semiconductor device to be manufactured has been described by taking the octagonal semiconductor device 4 as an example, the through portion 5 is formed at the four corners of the element portion 3 as shown in FIG. It is formed in a region including the intersection P between the scribe lines 2 other than the element portion 3. Each side of the penetrating portion 5 constitutes a part of the outer shape of the semiconductor device 4. Therefore, the shape of the penetrating portion 5 is formed in a quadrangular shape in accordance with the outer shape of the semiconductor device 4 to be manufactured.

  In addition, as shown in FIG. 3B, similarly, when the semiconductor device to be manufactured is a circular semiconductor device 4, the penetrating portion 5 has scribes other than the element portion 3 at the four corners of the element portion 3. It is formed in a region including the intersection P between the lines 2. Each side of the penetrating portion 5 is formed in a shape of a ¼ partial circle, and constitutes a part of the outer shape of the adjacent semiconductor device 4.

  Further, as shown in FIG. 3C, when the semiconductor device to be manufactured is a hexagonal semiconductor device 4, similarly, the penetrating portion 5 includes each of the four corner portions of the element portion 3 except for the element portion 3. It is formed in a region including the intersection P between the scribe lines 2. Each side of the penetrating portion 5 constitutes a part of the outer shape of the semiconductor device 4. Therefore, the shape of the penetrating portion 5 is formed in a rhombus shape in accordance with the outer shape of the semiconductor device 4 to be manufactured.

  Note that the penetrating portion 5 is formed in the same manner even in a semiconductor device other than the above-described circular, hexagonal, and octagonal semiconductor devices.

  After the above-described through-portion forming step, the process proceeds to a dicing step. As shown in FIG. 4A, the wafer 1 is diced along the scribe line 2 so that each semiconductor device 4 is divided. Is created.

  In this dicing process, each semiconductor device 4 is separated into pieces by using normal mechanical blade dicing or a laser dicing apparatus that separates the crystal faces by cleavage.

  The example shown in FIG. 4A shows a dicing process in which the orientation flat OF direction corresponding to FIG. 2A is <110>, but the orientation flat OF direction corresponding to FIG. 100>, when the layout of the arrangement of the element portions 3 and the like is rotated by 45 degrees as shown in FIG. 4B, the dicing process is similarly rotated by 45 degrees as shown in FIG. To do.

  As described above, according to the first embodiment of the present invention, a substantially circular or polygonal semiconductor device that can be miniaturized in the radial direction, particularly in a cylindrical device such as an endoscope device or the like. Can be manufactured with good performance.

  In the first embodiment of the present invention, each semiconductor device is not formed into a substantially circular or polygonal shape, but is formed in a lump in a wafer process before being separated into individual pieces. It is possible to cope with it, the workability is good, and the cost can be reduced.

  Furthermore, in the first embodiment of the present invention, if chemical processing such as etching that does not cause chipping is used in the through-hole forming step, the dicing area where the influence of chipping is caused by blade dicing is reduced, and the dicing blade is also reduced. Since it becomes possible to abut at an obtuse angle with respect to the portion where dicing is started, reliability is also improved.

  In addition, if the dicing process of the present invention uses a laser dicing apparatus that divides into pieces by cleavage of the crystal plane and is used in combination with the above-described through-hole forming process by chemical processing, a process in which no chipping occurs is realized in all processes. And reliability is further improved.

  Next, FIG. 5 is a cross-sectional view of a wafer on which a penetrating portion according to a second embodiment of the present invention is formed. The second embodiment differs from the first embodiment in that the penetrating portion forming step is performed from both the front and back surfaces, and the other configurations and processes are the same as the first embodiment. Are denoted by the same reference numerals, and description thereof is omitted.

  That is, as shown in FIG. 5, in the penetration portion forming step according to the second embodiment, the penetration portion 5 is formed by wet anisotropic etching, for example, and both surfaces of the front surface 1 a and the back surface 1 b of the wafer 1 are formed. Then, a protective film for wet anisotropic etching is formed, and etching is performed simultaneously from both the front surface 1 a and the back surface 1 b of the wafer 1.

  Thus, according to the second embodiment of the present invention, the etching time required for forming the penetrating portion 5 is halved compared to the first embodiment, which can further contribute to cost reduction.

In particular, when wet anisotropic etching is used to form the penetrating portion 5, the depth of the penetrating portion 5 is proportional to the size of each side of the surface of the penetrating portion 5. It can be reduced to 1/2 of L) in the figure, and thereby the area of the penetrating portion 5 can also be reduced to (1/2) ² = ¼. For this reason, since the dimension of the penetrating part 5 can be freely selected between 1/2 and 1.0 times, it can be easily applied to a small package type semiconductor device. The degree of freedom can be improved.

  Next, FIG. 6 is a cross-sectional view of the wafer for explaining the through-hole forming step according to the third embodiment of the present invention. In the third embodiment, the through-hole forming step includes a trench step for forming a groove from the front surface of the wafer and a grinding step for polishing the wafer from the back surface to thin the wafer. Unlike other configurations and processes, which are the same as those in the first embodiment, the same components are denoted by the same reference numerals, and description thereof is omitted.

  That is, reference numeral 1 in FIG. 6A indicates a wafer on which a plurality of element portions 3 partitioned by a scribe line are formed in a normal wafer process (semiconductor manufacturing process).

  Then, with respect to the wafer 1 shown in FIG. 6 (a), the same area on the surface of the wafer 1 as that in which the penetrating part 5 in the first embodiment is formed, that is, the scribe lines other than the plurality of element parts 3 First, as shown in FIG. 6B, a groove 6 is formed in a region including the intersection of. That is, the process of forming the groove 6 is a trench process.

  In the trench process, the groove 6 is formed using chemical processing such as wet etching or dry etching, or physical processing such as sand blasting, laser water jet, or the like, similar to the formation of the through portion 5 of the first embodiment. It is formed.

  Thereafter, as shown in FIG. 6C, the wafer 1 is polished to have a thickness smaller than that of the back surface, so that the groove 6 becomes a through portion. That is, this process is a grinding process.

  The order of the trench process and the grinding process described above may be reversed. In addition, it is possible to perform the trench process from both surfaces of the wafer 1 by applying the second form to the third form, but in this case, it is necessary to perform the grinding process first.

  As described above, according to the third embodiment of the present invention, grinding can generally be performed in a shorter time than etching. Therefore, by reducing the wafer thickness, the time required for forming the through portion (groove portion) 6 can be reduced. It can be shortened and can contribute to cost reduction. Moreover, since the wafer 1 is thinned, the time required for the dicing process after the through-hole forming process can be shortened. Furthermore, since the wafer 1 can be made thinner, the load on the dicing blade is also reduced, and it becomes possible to improve the reliability and the durability of the dicing blade.

  As described above, according to the present invention, a substantially circular or polygonal semiconductor device that can be miniaturized in the radial direction, which is used in a cylindrical device (for example, an endoscope device) or the like, is improved in workability. Can be manufactured. In addition, each semiconductor device is not formed into a substantially circular or polygonal shape, but is formed in a lump in a wafer process before being singulated, so that it can be used for mass production, has good workability, and reduces costs. realizable. Furthermore, if chemical processing such as etching that does not cause chipping is used in the through-hole forming process of the present invention, the dicing area that is affected by chipping is reduced by blade dicing, so that the reliability is improved. In addition, if a laser dicing apparatus or the like that is separated into pieces by cleavage of crystal planes is used in the dicing process of the present invention, a semiconductor device that does not generate chipping can be realized, and the reliability can be further improved.

The front view of the wafer in which the element part was formed by 1st Embodiment of this invention Same as above, front view of wafer with through hole Same as above, enlarged illustration of penetration As above, an explanatory diagram of a semiconductor device diced by a scribe line Sectional drawing of the wafer in which the penetration part was formed by the 2nd Embodiment of this invention Sectional drawing of the wafer explaining a penetration part formation process by a 3rd embodiment of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wafer 2 Scribe line 3 Element part 4 Semiconductor device 5 Penetration part 6 Groove part (penetration part)

Claims (8)

A penetration part forming step of forming a penetration part penetrating the wafer in a region including an intersection of the scribe lines other than the element part of the wafer partitioned by the scribe line to form the element part;
A dicing step of dicing the wafer having the penetrating portion into individual semiconductor devices;
A method for manufacturing a semiconductor device, comprising:   The method of manufacturing a semiconductor device according to claim 1, wherein the through portion formed in the through portion forming step is a part of an outer shape of the semiconductor device.   3. The method of manufacturing a semiconductor device according to claim 1, wherein the penetrating portion forming step is performed by at least one of chemical processing and mechanical processing.   4. The method for manufacturing a semiconductor device according to claim 1, wherein the through-hole forming step is performed from both surfaces of the wafer. The penetrating portion forming step includes a trench step of forming a groove portion from the surface of the wafer,
A grinding step of thinning the wafer by polishing from the back surface of the wafer;
5. The method of manufacturing a semiconductor device according to claim 1, comprising:   6. The method of manufacturing a semiconductor device according to claim 5, wherein the through-hole forming step executes the grinding step after the trench step.   6. The method of manufacturing a semiconductor device according to claim 5, wherein the through-hole forming step executes the trench step after the grinding step.   A semiconductor device manufactured by the method for manufacturing a semiconductor device according to claim 1.

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