CN114683165A

CN114683165A - Method and apparatus for semiconductor processing

Info

Publication number: CN114683165A
Application number: CN202110180689.0A
Authority: CN
Inventors: 曾永标; 王胜德; 余幸芳
Original assignee: SPEEDFAM Inc
Current assignee: SPEEDFAM Inc
Priority date: 2020-12-31
Filing date: 2021-02-09
Publication date: 2022-07-01
Also published as: TWI797532B; CN214980191U; TW202228200A

Abstract

The present disclosure provides a method of semiconductor processing, comprising: providing a wafer, wherein the wafer is provided with a first surface and a second surface opposite to the first surface, and the wafer is provided with a plurality of semiconductor elements on the first surface; adhering a glue film to the wafer, wherein the glue film is provided with a third surface facing the first surface; fixing the frame on a fourth surface of the adhesive film opposite to the third surface; facing the second surface with the abrasive article; and grinding the wafer from the second surface.

Description

Method and apparatus for semiconductor processing

Technical Field

The present invention relates generally to semiconductor devices and semiconductor processing methods, and more particularly to methods and apparatus for polishing.

Background

Before the wafer is diced to form chips, a back grinding (backsgrind) process is performed. As the thickness of the wafer becomes thinner, the risk of wafer breakage during the wafer back grinding process also increases. In order to ensure that the wafer is not damaged and broken by thermal and mechanical stress during polishing, a film is generally adhered to the wafer for supporting and protecting so as to reduce the risk of wafer breakage during transportation.

In the conventional wafer back grinding process, a great improvement space is provided to improve the quality of the thinned wafer.

Therefore, there is a need for improvement of the current wafer lamination method and polishing apparatus to reduce the cost and increase the wafer polishing efficiency.

The above "prior art" description is provided merely as background, and no admission is made that the above "prior art" description discloses the subject matter of the present disclosure, does not constitute prior art to the present disclosure, and any description of the above "prior art" should not be taken as an admission that any of the above is prior art to the present disclosure.

Disclosure of Invention

One aspect of the present disclosure provides a semiconductor processing apparatus including a central region and a peripheral region. The central area is used for bearing a wafer and is provided with a first surface. The peripheral area surrounds the central area and is used for bearing the frame, and the peripheral area is provided with a second surface higher than the first surface.

In some embodiments, the central region is substantially circular in plan view.

In some embodiments, the central region includes a first suction member for sucking the wafer, the first suction member being located below the first surface.

In some embodiments, the first suction attachment has a vacuum suction device.

In some embodiments, the semiconductor processing apparatus further comprises a trench disposed between the central region and the peripheral region, wherein the trench surrounds the central region.

One aspect of the present disclosure provides another semiconductor processing apparatus including a central region and a peripheral region. The central area is used for bearing a wafer and is provided with a first surface. The peripheral area surrounds the central area and is used for bearing the frame, and the peripheral area is provided with a second surface lower than the first surface.

In some embodiments, the first surface is spaced from the second surface by a distance equal to the height of the frame.

In some embodiments, the peripheral area includes a second adsorption member for adsorbing the frame, and the second adsorption member is located below the second surface.

In some embodiments, the second suction member has a vacuum or magnetic suction device.

Another aspect of the present disclosure provides a method for processing a wafer, including: providing a wafer, wherein the wafer is provided with a first surface and a second surface opposite to the first surface, and the wafer is provided with a plurality of semiconductor elements on the first surface; adhering a glue film to the wafer, wherein the glue film is provided with a third surface facing the first surface; fixing the frame on a fourth surface of the adhesive film opposite to the third surface; facing the second surface with the abrasive article; and grinding the wafer from the second surface.

In some embodiments, the step of attaching the adhesive film to the wafer includes providing a carrier device, the carrier device including a first central region and a first peripheral region surrounding the first central region; placing the wafer on the first central area, wherein the second surface of the wafer faces the bearing device; and adhering the adhesive film on the wafer and the first peripheral area to be adhered with the wafer.

In some embodiments, the method further includes using the suction member to suck the wafer after the wafer is placed on the carrier device.

In some embodiments, the method for processing the wafer further includes adjusting a surface height of the first central region according to the thickness of the wafer, so that the adhesive film has an equal height in the first central region and the first peripheral region.

In some embodiments, the step of fixing the frame to the fourth surface of the adhesive film opposite to the third surface comprises applying an adhesive to cause the frame to adhere to the adhesive film in a concentric circle with the wafer.

In some embodiments, the method further includes cutting the outer portion of the adhesive film such that the cut edge of the adhesive film is aligned with the outer edge of the frame.

In some embodiments, the step of polishing the wafer from the second surface includes securing the wafer to the process fixture, wherein the frame circumferentially surrounds a second central region of the process fixture.

In some embodiments, the process fixture includes a second peripheral region surrounding the second central region, and the second peripheral region has a fifth surface lower than a sixth surface of the central region.

In some embodiments, the method further comprises providing a transfer device to remove the wafer from the processing fixture after polishing the wafer.

In some embodiments, the transfer device comprises a first suction part and a second suction part surrounding the first suction part, wherein the first suction part has a vacuum suction device for sucking the wafer, and the second suction part has a vacuum or magnetic suction device for sucking the frame.

Therefore, the present disclosure provides a novel method for attaching a film to a wafer and a polishing apparatus, wherein a frame and the wafer are attached to the opposite side of a film for carrying and polishing, so as to reduce the probability of wafer breakage caused by pulling the film during polishing, and meanwhile, the film has sufficient tension to carry the thinned wafer, thereby improving the polishing quality of the wafer.

The foregoing has outlined rather broadly the features and advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures or processes for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims.

Drawings

The disclosure of the present application may be more completely understood in consideration of the following detailed description of the embodiments and the appended claims, in connection with the accompanying drawings, in which like reference numerals refer to like elements.

Fig. 1 is a perspective view of a wafer frame unit according to a comparative example of the prior art.

Fig. 2 is a flow chart of a wafer processing method in accordance with some embodiments of the present disclosure.

Fig. 3-10 are schematic diagrams illustrating operational steps of the wafer processing method according to fig. 2, respectively, according to some embodiments of the present disclosure.

FIG. 11 is a perspective view of a wafer frame unit according to some embodiments of the present disclosure

Fig. 12 is a side view of a wafer frame unit, according to some embodiments of the present disclosure.

Fig. 13-18 are schematic diagrams depicting, respectively, operational steps in the method of processing a wafer according to fig. 2, in accordance with some embodiments of the present disclosure.

Detailed Description

Embodiments of the present disclosure are discussed in detail below. It should be appreciated, however, that the embodiments provide many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative of specific ways to make and use the embodiments, and do not limit the scope of the disclosure.

Like reference numerals are configured to refer to like elements throughout the various views and illustrative embodiments. Reference will now be made in detail to exemplary embodiments that are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings and the description to refer to the same or like parts. In the drawings, the shape and thickness may be exaggerated for clarity and convenience. The description will be directed in particular to elements forming part of, or cooperating more directly with, apparatus in accordance with the disclosure. It is to be understood that elements not specifically shown or described may take various forms. Reference throughout this specification to "some embodiments" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in some embodiments" or "in embodiments" in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

In the drawings, like numerals are configured to indicate like or similar elements throughout the several views, and illustrative embodiments of the present invention are shown and described. The figures are not necessarily drawn to scale and in some instances, the figures have been exaggerated and/or simplified, configured for illustrative purposes only. Many possible applications and variations of the present invention will be understood by those of ordinary skill in the art based on the following illustrative embodiments of the invention.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which embodiments of the present disclosure belong. It will be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure and will not be interpreted, or interpreted, in an overly formal sense unless expressly defined herein.

In addition, the following examples are provided to illustrate the core value of the disclosure, but not to limit the scope of the disclosure. For purposes of clarity and understanding, the same or similar functions or elements are not repeated in the figures or description for different embodiments of the disclosure. Moreover, different elements or technical features of different embodiments may be combined or substituted without conflict with each other to obtain a new embodiment, which still belongs to the scope of the present disclosure.

When the thickness of the wafer is less than 100 μm, the adhesive film adhered on the wafer cannot provide enough supporting capability for the wafer. Referring to fig. 1, fig. 1 is a perspective view of a wafer frame unit 100 according to the prior art. The wafer frame unit 100 includes a wafer 21, a film 23, and a frame 25. The wafer 21 has a first surface 21A and a second surface 21B opposite to each other. The first surface 21A of the wafer 21 may be a front surface of the wafer, and the second surface 21B may be a back surface of the wafer. A plurality of semiconductor elements 22 are formed on the first surface 21A. The adhesive film 23 is adhered to the first surface 21A. The frame 25 is fixed to the adhesive film 23 via the same side as the wafer 21.

In the conventional wafer lamination method, the wafer 21 and the frame 25 are located on the same side of the adhesive film 23. Since the frame 25 has a certain thickness, when the second surface 21B of the wafer 21 is polished, the height of the frame 25 used must be lower than the final polishing thickness of the wafer 21, which causes limitation in use of the frame 25. In addition, when the wafer 21 and the frame 25 are polished while being positioned on the same side as the adhesive film 23, the frame 25 is pushed down and pulls the adhesive film 23, so that the adhesive film 23 cannot be reliably adhered to the wafer 21, but stress is applied to the wafer 21, the purpose of protecting the wafer 21 by the frame 25 is lost, and edge crack or breakage of the wafer 21 is likely to occur.

Fig. 2 is a flow chart of a wafer polishing method 200 in accordance with some embodiments of the present disclosure. Referring to fig. 2, the method 200 includes steps 101,103,105,107,109, and 111. Fig. 3-10 and 13-18 are schematic diagrams illustrating steps performed in a wafer polishing method 200 according to some embodiments of the present disclosure.

In step 101, a wafer 1 is provided, as shown in fig. 3. In some embodiments, wafer 1 comprises a wafer substrate of a semiconductor material, such as silicon, gallium arsenide, silicon carbide, gallium nitride, sapphire (aluminum oxide), and the like, including but not limited to germanium, selenium, gallium phosphide, indium antimonide, indium phosphide, indium arsenide, gallium antimonide, zinc oxide, strontium titanate, magnesium oxide, lanthanum aluminate, lithium niobate, lithium tantalate, borosilicate, graphene, a plated silicon wafer, a quartz substrate, an indium tin oxide substrate, and the like. In some embodiments, the wafer 1 may also be replaced by a non-semiconductor material, including but not limited to a glass substrate, an optoelectronic substrate, a ceramic substrate, a metal substrate, or the like.

In some embodiments, the wafer 1 has a first surface 1A and a second surface 1B opposite to each other. In some embodiments, the first surface 1A of the wafer 1 is a front surface of the wafer and the second surface 1B is a back surface of the wafer. In some embodiments, wafer 1 is circular. In other embodiments, the shape of the wafer 1 is not limited to circular, and other types of wafers with thinning or transferring requirements, such as quadrilateral or polygonal, can be included in the scope of the present disclosure.

In some embodiments, a plurality of semiconductor devices 2 are formed on the first surface 1A, and the semiconductor devices 2 include active devices or passive devices, and the active and passive electronic devices are electrically connected to each other to form different functional circuits. In some embodiments, the semiconductor device 2 may include various transistors, such as N-metal-oxide-semiconductor (NMOS) and/or P-metal-oxide-semiconductor (PMOS) devices. In some embodiments, the semiconductor device 2 may include devices such as a rectifier, a vacuum tube, a capacitor, a resistor, a diode (diode) or a light-emitting diode (LED), and is applied in the fields of micro-electro-mechanical systems (MEMS), complementary metal-oxide-semiconductor (CMOS), three-dimensional integrated circuits (3 DIC), memory chips, logic chips, power management (power management) chips, Radio Frequency (RF) chips, semiconductor interposers (semiconductor interposers), Schottky diodes (Schottky diodes), or Insulated Gate Bipolar Transistors (IGBTs).

Referring to fig. 2, in step 103, the adhesive film 3 is attached to the wafer 1 (see fig. 4 to 6). Referring to fig. 4, in some embodiments, a carrier 400 is provided as a semiconductor processing apparatus for attaching the adhesive film 3 to the wafer 1. In some embodiments, the carrier 400 includes a central region 14 and a peripheral region 15. The central region 14 is a circular platform in plan view, which is the main region for carrying the wafer 1, and the peripheral region 15 is an annular platform surrounding the central region 14. In some embodiments, the width (or diameter) of the central region 14 is substantially equal to the diameter of the wafer 1. In some embodiments, central region 14 is connected to peripheral region 15 with a trench 16 therebetween. In some embodiments, the trench 16 is annular and surrounds the central region 14.

With continued reference to fig. 4, the central region 14 has a surface 14a, the peripheral region 15 has a surface 15a, and the trench 16 has a surface 16 a. In some embodiments, the central region 14 includes a lift table 18 that can adjust the height T1 of the surface 14a to control the vertical position of the wafer 1 carried thereon. In addition, by adjusting the height T1, the surface 15a can be higher than the surface 14a by a distance S1. In some embodiments, the distance S1 is adjustable to accommodate different wafer 1 thicknesses and different process requirements. In some embodiments, the central region 14 has a suction member 13 below the surface 14a and above the lift platform 18, such as a vacuum suction device, which provides a suction force on the wafer 1 to hold the wafer 1 on the central region 14. In some embodiments, the peripheral region 15 has a vacuum suction device or a magnetic suction device (which may be a magnet or an electromagnet) that can provide suction to a point, line, or surface of the frame 5 to secure the frame 5 to the peripheral region 15. In some embodiments, the peripheral region 15 has a base 9, an ultraviolet light source 10, and a light transmissive material 11. The ultraviolet light source 10 is located above the base 9 for providing at least one wavelength for curing or disperging. The light transmissive material 11 is located above the ultraviolet light source 10 and below the surface 15 a. In some embodiments, the light transmissive material 11 includes, but is not limited to, a glass or quartz material. In some embodiments, the uv light source 10 and the light transmissive material 11 may be disposed in the trench 16 according to different process requirements, wherein the light transmissive material 11 is located above the uv light source 10 and below the surface 16 a.

Referring to fig. 5, in some embodiments, the wafer 1 is placed on the central region 14 with the first surface 1A facing upward, while the second surface 1B of the wafer 1 faces the surface 14a of the central region 14 and is adsorbed by the adsorbing member 13. In some embodiments, after placing the wafer 1 in the central region 14, the surface 15a of the peripheral region 15 is made of a low-adhesion material, and the height T1 is adjusted by the lifting platform 18, so that the first surface 1A of the wafer 1 is substantially at the same level as the surface 15 a. In some embodiments, after placing the wafer 1 in the central region 14, the surface 15a of the peripheral region 15 may be coated with a release agent 12, which is an adhesive that reduces its viscosity by, for example, light or heat. In some embodiments, after coating the release agent 12, the height T1 is adjusted by the lifting platform 18 so that the first surface 1A of the wafer 1 and the release agent 12 on the surface 15a have substantially the same level.

Referring to fig. 6, the adhesive film 3 is attached to the wafer 1 on the carrier 400. In some embodiments, the adhesive film 3 is a special adhesive film suitable for polishing and thinning, and has no ductility. In other embodiments, the adhesive film 3 may also be stretchable to be easily stretched. In some embodiments, the adhesive film 3 includes, but is not limited to, a polymer material, such as Polyimide (PI), Polyolefin (PO), polypropylene (PP), Polyethylene (PE), polyethylene terephthalate (PET), Polyurethane (PU), Ethylene Vinyl Acetate (EVA), polyvinyl chloride (PVC), Polystyrene (PS), Polyether (PEs), or the like. The adhesive film 3 has

opposite surfaces

3A and 3B. In some embodiments, the adhesive film 3 is adhered to the wafer 1 with the surface 3A facing the first surface 1A, and the surface 3A of the adhesive film 3 is also adhered to the peripheral area 15 through the release agent 12. In some embodiments, when the adhesive film 3 needs to be removed from the peripheral region 15, the release agent 12 can be irradiated or heated to reduce the adhesiveness of the release agent 12, so that the adhesive force between the surface 3A and the surface 15a is reduced, and the adhesive film 3 can be easily removed from the peripheral region 15. In other embodiments, the adhesive film 3 may be removed from the surrounding area 15 only by the difference in adhesion strength between the surface 3A and the surface 3B.

In some embodiments, the height T1 can be adjusted by the lift platform 18 so that the first surface 1A of the wafer 1 and the surface 15a have substantially the same horizontal plane. In some embodiments, when the adhesive film 3 needs to be removed from the peripheral region 15, light can be applied or heat can be applied to the contact between the adhesive film 3 and the peripheral region 15 to remove the adhesive film 3 from the peripheral region 15. In some embodiments, the height T1 may be precisely adjusted to change the height of the surface 14a according to the thickness of the wafer 1, so that the height of the adhesive film 3 in the central region 14 is substantially equal to that in the peripheral region 15, so that the adhesive film 3 appears horizontal. In some embodiments, the groove 16 may provide a gap to prevent the adhesive film 3 from adhering to the carrier 400 completely, so as to reduce the adhesion between the adhesive film 3 and the release agent 12, and facilitate the removal of the adhesive film 3 together with the wafer 1 from the carrier 400.

Referring to fig. 2, in step 105, the frame 5 is fixed on the adhesive film 3, as shown in fig. 7 to 10. Referring to fig. 7, in some embodiments, the adhesive 7 is coated on the bottom surface 3B of the adhesive film 3 on the peripheral area 15. In some embodiments, the adhesive 7 may be a solvent, thermosetting or UV type adhesive in the form of a solid, liquid, or adhesive film.

Referring to fig. 8, the frame 5 is placed on the peripheral area 15 in such a manner as to align the adhesive 7. In some embodiments, the frame 5 has a height R1 that appears annular in plan view. In some embodiments, the frame 5 surrounds the wafer 1 and the central region 14, and is disposed on the opposite side of the adhesive film 3 from the wafer 1. In other embodiments, the adhesive 7 may be coated on the bottom surface of the frame 5 in advance, and then placed on the adhesive film 3 in such a manner that the bottom surface of the frame 5 faces the surface 3B. In some embodiments, the adhesive film 3 is adhered to the first surface 1A of the wafer 1 and extends beyond the outer edge of the frame 5, so that the bottom surface of the frame 5 is completely contained within the adhesive film 3. In some embodiments, the frame 5 and the wafer 1 are concentrically placed on the peripheral region 15 and the central region 14 of the carrier 400, respectively.

Referring to fig. 9, the uv light source 10 is turned on to generate a uv light hv1 through the light transmissive material 11. In some embodiments, the adhesive 7 is irradiated by the ultraviolet light hv1 to perform a photochemical reaction and thus be cured, so that the frame and the adhesive film 3 can be tightly adhered. In some embodiments, the adhesive film 3 is secured by the frame 5 to obtain sufficient tension to maintain an absolute planar foundation for supporting and protecting the wafer 1.

Referring to fig. 10, in some embodiments, after the frame 5 and the adhesive film 3 are tightly fixed, a portion of the adhesive film 3 located at the outer edge of the frame 5 is removed. In some embodiments, a cutting tool (not shown) may be used to cut the adhesive film 3 along a cutting path in the cutting direction C1. In some embodiments, the cutting path is the outermost edge of the frame 5, and the adhesive film 3 is cut along the outermost edge of the frame 5 by a cutting tool, such that the cut edge of the adhesive film 3 is aligned with the outermost edge of the frame 5 to remove the excess adhesive film 3, and the remaining adhesive film 3 is adhesively fixed on the frame 3. In some embodiments, the cut edge of the adhesive film 3 may be cut flush with the outermost edge of the frame 5 or recessed within the frame 5.

Fig. 11 is a perspective view of a wafer frame unit 150 according to some embodiments of the present disclosure. After completing step 105, the wafer 1, the adhesive film 3 and the frame 5 form a wafer frame unit 150. In some embodiments, the wafer frame unit 150 may be flipped over by a robot or by human action. The wafer frame unit 150 shown in fig. 11 is placed with the first surface 1A facing upward. In some embodiments, the wafer frame unit 150 may be transported, transferred, or ground or otherwise processed.

Fig. 12 is a side view of a wafer frame unit 150 according to some embodiments of the present disclosure. The wafer frame unit 150 shown in fig. 12 is placed with the second surface 1B facing upward. In the present disclosure, the frame 5 and the wafer 1 are respectively disposed on opposite sides of the adhesive film 3 by the technique of attaching the frame 5, and in this configuration, the wafer 1 can be protruded for performing the subsequent steps, such as the polishing process, without considering the relative thickness of the frame 5 and the wafer 1. Compared with the prior art shown in fig. 1, the method can effectively perform the wafer backside thinning process without pressing the frame 5 to expose the second surface 1B of the wafer 1, thereby eliminating other complicated or expensive processes and achieving the advantages of low cost and reliability.

Referring to FIG. 2, in step 107, the wafer 1 is polished, as shown in FIGS. 13-14. Referring to fig. 13, in some embodiments, a polishing apparatus 500 is provided as a semiconductor processing apparatus, wherein the polishing apparatus 500 includes a processing fixture 32 and a polishing portion 34, which are separated from each other. In some embodiments, the tool holder 32 includes a central region 31 and a peripheral region 33, the peripheral region 33 surrounding the central region 31, both having different planes. Specifically, the central area 31 has a top surface 31A, the peripheral area 33 has a top surface 33A lower than the top surface 31A, and the top surface 31A and the top surface 33A have a distance D1 therebetween to accommodate the frame 5. In some embodiments, the distance D1 may be controlled by adjusting the relative planar heights of the central region 31 and the peripheral region 33 to correspond to different heights R1 of the frame 5 for different applications. In some embodiments, the distance D1 between the top surface 31A and the top surface 33A is substantially equal to the height R1 of the frame 5. In some embodiments, the grinding section 34 has a grinding shaft 35 and a grinding stone 36 connected to the grinding shaft 35. The abrasive article 36 has a substantially flat surface platform. The abrasive article 36 may be comprised of any suitable material, such as, but not limited to, abrasive grain abrasives such as diamond wheels, polyurethane blocks, polyurethane chips, polyurethane impregnated polyester felt, and the like.

With continued reference to fig. 13, in some embodiments, the central region 31 has a suction member 41, such as a vacuum suction device, below the top surface 31A, which may provide a suction force to the wafer 1 to hold the wafer 1 on the central region 31. In some embodiments, peripheral region 33 has a suction attachment 43, such as a magnetic device (which may be a magnet or an electromagnet) or a vacuum suction device, below top surface 33A that provides a suction force to a point, line, or face of frame 5 to secure frame 5 to peripheral region 33. The wafer frame unit 150 is fixed to the process fixing portion 32 by the reverse supporting method through the suction member 41 of the central region 31 and the suction member 43 of the peripheral region 33. In some embodiments, in the polishing apparatus 500, the second surface 1B of the wafer 1 is made to face the polishing abrasive 36 of the polishing part 34. In some embodiments, the polishing portion 34 can be moved according to the process requirements, and the distance between the polishing portion and the processing fixture 32 can be adjusted.

Referring to fig. 14, in some embodiments, after the wafer frame unit 150 is fixed to the processing fixing portion 32, the frame 5 surrounds the central region 31 of the processing fixing portion 32 from the periphery, and the second surface 1B of the wafer 1 faces the grinding wheel 36, and the center of the wafer 1 is only a predetermined distance away from the rotation center of the grinding wheel 36. Then, the polishing portion 34 approaches the wafer 1 at an adjustable attack speed until the polishing abrasive 36 abuts against the second surface 1B of the wafer 1, thereby starting polishing. As the grinding shaft 35 rotates, the grinding stone 36 also rotates in the Z-axis direction. In some embodiments, the abrasive article 36 is pressed against the second surface 1B of the wafer 1. With the rapid rotation of the grinder 36, the abutment portion of the grinder 36 with the second surface 1B is precisely ground and the ground second surface 1B is chipped, so that the wafer 1 is gradually thinned during the grinding process, and the wafer thickness W1 is gradually reduced. In some embodiments, the grinding shaft 35 may rotate the grinding tool 36 at an adjustable speed, which is adjusted according to the thickness of the second surface 1B to be ground. In other embodiments, during rotation of the grinding tool 36, the wafer 1 is also rotated, thereby allowing for more precise grinding.

In some embodiments, after the wafer 1 is polished by the polishing apparatus 500, the thinned wafer 1 is still fixed on the wafer frame unit 150. During the process of polishing the wafer 1 by the polishing part 34, the frame 5 can fix the adhesive film 3 and maintain the smoothness of the adhesive film 3, so as to provide sufficient tension to the adhesive film 3, thereby preventing the shape of the adhesive film 3 from being damaged. In addition, the wafer 1 is attached by the adhesive film 3 and supported by the frame 5, so as to provide protection and bearing force during polishing. On the other hand, the wafer frame unit 150 is disposed on the polishing apparatus 500 in such a manner that the frame 5 and the wafer 1 are disposed on the opposite sides of the adhesive film 3, respectively, so that the polishing portion 34 can reduce the probability of wafer breakage caused by pulling of the adhesive film during the polishing process in the process of polishing the second surface 1B of the wafer 1, thereby obtaining a better thinning quality of the wafer 1.

Referring to FIG. 2, in step 109, the wafer is transferred, as shown in FIGS. 15-17. Referring to fig. 15, in some embodiments, a transfer device 600 is provided, the transfer device 600 includes a first suction portion 61, a second suction portion 62, and a connection portion 65, and the first suction portion 61 and the second suction portion 62 are connected through the connection portion 65. In some embodiments, the first suction portion 61 is used for sucking the wafer 1, so the width or diameter of the first suction portion 61 is substantially equal to the diameter of the wafer 1. In some embodiments, the second adsorption part 62 surrounds the first adsorption part 61 and has a ring structure.

In some embodiments, both the first adsorption part 61 and the second adsorption part 62 have different plane heights. Specifically, the first suction portion 61 has a top surface 61A, the second suction portion 62 has a top surface 62A, and a height difference H1 is provided between the top surface 61A and the top surface 62A. In some embodiments, the first absorption part 61 can adjust the height difference H1 by the connection part 65. In some embodiments, the height difference H1 is substantially equal to the thickness W1.

Referring to fig. 16, in some embodiments, the first suction part 61 has a suction member, such as a vacuum suction device, which can provide a suction force to the wafer 1 to fix the wafer 1 on the first suction part 61. In some embodiments, the second suction portion 62 has a vacuum suction device or a magnetic suction device (which may be a magnet or an electromagnet), and may provide suction to a point, a line, or a surface of the frame 5 to fix the frame 5 on the second suction portion 62. The wafer frame unit 150 can be fixed to the transfer device 600 with the second surface 1B facing upward by the suction devices of the first suction unit 61 and the second suction unit 62. In some embodiments, the wafer frame unit 150 may be transferred by a transfer device 600, for example, the transfer device 600 may transport the wafer frame unit 150 and transfer the wafer frame unit 150 into the polishing apparatus 500 or out of the polishing apparatus 500, but is not limited thereto. In other embodiments, the wafer frame unit 150 may be placed on the polishing apparatus 500 by other methods, such as manual or mechanical arm, and the wafer frame unit 150 may be moved out of the polishing apparatus 500 by the moving apparatus 600 after the wafer is thinned. In some embodiments, when the transfer device 600 transfers the wafer frame unit 150, the connecting portion 65 raises and lowers the first suction portion 61 to adjust the height difference H1 at any time to correspond to different wafer thicknesses W1 before and after polishing.

Referring to fig. 17, fig. 17 is a schematic view showing that after the wafer 1 is polished and thinned, the wafer frame unit 150 is transferred to the processing fixing portion 32 by the transfer device 600. At this time, the distance D1 between the central area 31 and the peripheral area 33 is substantially equal to the height R1 of the frame 5, and the height difference H1 between the first suction portion 61 and the second suction portion 62 is also substantially equal to the thinned wafer thickness W1. The transfer device 600 transfers the wafer 1 out of the processing fixing portion 32 in such a manner that the second surface 1B of the wafer 1 faces upward, and conveys the wafer 1 to a subsequent process.

In some embodiments, after the polishing thinning of the wafer 1 is completed, a back wet etching (backside wet etching) is performed on the wafer 1 to remove a wafer damage layer generated by polishing and release the polishing stress.

Referring to fig. 2, in step 111, the adhesive film 3 is subjected to adhesive release, as shown in fig. 18. In some embodiments, after the wafer 1 is polished and thinned, a debonding process may be performed on the wafer frame unit 150. Fig. 18 shows the wafer frame unit 150 disposed with the second surface 1B facing upward, and the wafer frame unit 150 is irradiated with, for example, ultraviolet light hv2, so that the adhesive 7 between the adhesive film 3 and the frame 5 and the ultraviolet light hv2 undergo a photochemical reaction to remove the adhesion of the adhesive 7. Thus, the frame 5 can be separated from the wafer 1 after polishing, and the wafer back polishing process can be completed.

In some embodiments, the carrier 400, the polishing device 500, and the transfer device 600 may be used in combination with the wafer frame unit 150 to provide the functions of carrying, polishing, and transferring the wafer 1, which may be closely combined, for example, according to the complete process from step S101 to step S111 to complete the thinning process of the wafer 1. In other embodiments, the carrier 400, the polishing apparatus 500, or the transferring apparatus 600 may be operated independently, and only one or two of the carrier 400, the polishing apparatus 500, or the transferring apparatus 600 may be used according to actual requirements. In some embodiments, the carrying apparatus 400 may be used for carrying the wafer 1 to form the wafer frame unit 150 according to only steps S101 to S105, wherein the wafer frame unit 150 may be used for other processes. In some embodiments, the polishing apparatus 500 may be used to provide polishing purposes for the wafer 1 according to only step S107, wherein the wafer frame unit 150 may be provided by steps S101 to S105, or by other steps. In some embodiments, the transfer apparatus 600 may be used to transfer the wafer 1 before or after thinning according to step S109.

Although the present disclosure and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the disclosure as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present disclosure. Accordingly, such processes, machines, manufacture, compositions of matter, means, methods, or steps, are included within the scope of the present application.

Description of the symbols

1,21: wafer

1A,21A first surface

1B,21B second surface

2,22 semiconductor element

3,23 adhesive film

3A adhesive film front

3B adhesive film back

5,25: ring frame

7,27 adhesive

9: base

10 ultraviolet light source

11 light-transmitting material

12 release agent

400 bearing device

13, an adsorption member

14,31 center area

15,33 surrounding area

16: groove

18: lifting platform

14a,15a,16a surface

C1 cutting direction

100,150 wafer frame unit

500 grinding device

32 machining fixing part

34 grinding part

35 grinding shaft

36 grinding tool

31A,33A,61A,62A top surface

hv1, hv2 ultraviolet light

S1, D1 distance

T1, R1 height

H1 height difference

W1 thickness

600 transfer device

61 first adsorption part

62 second adsorption part

65 connecting part

101,103,105,107,109,111 step

200 method

Claims

1. A semiconductor processing apparatus, comprising:

a central region for carrying a wafer, the central region having a first surface; and

a peripheral area surrounding the central area and used for carrying a frame, wherein the peripheral area is provided with a second surface higher than the first surface.

2. The semiconductor processing apparatus of claim 1, wherein the central region is substantially circular in plan view.

3. The semiconductor processing apparatus of claim 1, wherein the central region comprises a first suction feature for sucking the wafer, the first suction feature being located below the first surface.

4. The semiconductor processing apparatus of claim 3, wherein the first suction attachment has a vacuum suction device.

5. The semiconductor processing apparatus of claim 1, further comprising a trench disposed between the central region and the peripheral region, wherein the trench surrounds the central region.

6. A semiconductor processing apparatus, comprising:

a peripheral area surrounding the central area and used for carrying a frame, wherein the peripheral area is provided with a second surface lower than the first surface.

7. The semiconductor processing apparatus of claim 6, wherein a distance between the first surface and the second surface is equal to a height of the frame.

8. The semiconductor processing apparatus of claim 6, wherein the central region comprises a first getter for gettering the wafer, the first getter being located below the first surface.

9. The semiconductor processing apparatus of claim 6, wherein the peripheral region comprises a second suction member for sucking the frame, the second suction member being located below the second surface.

10. The semiconductor processing apparatus of claim 9, wherein the second suction member has a vacuum or magnetic device.

11. A method of processing a wafer, comprising:

providing a wafer, wherein the wafer is provided with a first surface and a second surface opposite to the first surface, and the wafer is provided with a plurality of semiconductor elements on the first surface;

adhering a glue film to the wafer, wherein the glue film has a third surface facing the first surface;

fixing a frame on a fourth surface of the adhesive film opposite to the third surface;

facing the second surface to a grinding tool; and

the wafer is polished from the second surface.

12. The method of claim 11, wherein the step of attaching the adhesive film to the wafer comprises:

providing a bearing device, wherein the bearing device comprises a first central area and a first peripheral area surrounding the first central area;

placing the wafer on the first central area, wherein the second surface of the wafer faces the carrier; and

the adhesive film is adhered to the wafer and the first peripheral region to adhere to the wafer.

13. The method of claim 12, further comprising using a suction tool to suction the wafer after it is placed on the carrier.

14. The method of claim 12, further comprising adjusting a surface height of the first central region according to a thickness of the wafer such that the adhesive film has an equal height in the first central region and the first peripheral region.

15. The method of claim 11, wherein the step of securing the frame to the fourth surface of the adhesive film opposite the third surface comprises:

applying an adhesive to make the frame adhere to the adhesive film in a concentric circle with the wafer.

16. The method of claim 11, further comprising:

cutting a peripheral part of the adhesive film to make the cut edge of the adhesive film be aligned with the outer edge of the frame.

17. The method of claim 11, wherein the step of polishing the wafer from the second surface comprises:

the wafer is fixed on a processing fixing part, wherein the frame surrounds a second central area of the processing fixing part from the periphery.

18. The method of claim 17, wherein the tool holder portion includes a second peripheral region surrounding the second central region, and the second peripheral region has a fifth surface lower than a sixth surface of the central region.

19. The method of claim 17, further comprising:

providing a transfer device to remove the wafer from the processing fixing part after polishing the wafer.

20. The method of claim 19, wherein the transfer device comprises a first suction portion and a second suction portion surrounding the first suction portion, wherein the first suction portion has a vacuum suction device for sucking the wafer, and the second suction portion has a vacuum or magnetic suction device for sucking the frame.