Patent Publication Number: US-2009236260-A1

Title: Chip Scale Package Tray

Description:
TECHNICAL FIELD 
     The present invention relates to a chip scale package tray, and more particularly to a chip scale tray which is capable of preventing semiconductor chips from being damaged when the chips are loaded on the tray, preventing the semiconductor chips from moving away from predetermined positions while they are loaded on the tray, so that the semiconductor chips can be smoothly adsorbed by a semiconductor chip suction device, preventing a working line in a manufacturing process from being interrupted, thereby improving work efficiency, preventing slippage between trays when a plurality of trays loaded with semiconductor chips are stacked and handled, and allowing the rear side inspection of the semiconductor chips as well as the front side inspection of the semiconductor chips after the chips are loaded on the trays, the rear side inspection being performed by turning the trays upside down. 
     BACKGROUND ART 
     As generally known in the art, semiconductor chips include CFP type chips, VGFP type chips, POFP chips, VSOP type chips, BGA type chips, etc. After the manufacturing of such semiconductor chips is completed, they are inputted into a manufacturing line for applying them, or they are delivered to the outside. In order to prevent the damage of semiconductor chips caused by external impact or the like occurring in the process of handling the semiconductor chips in a manufacturing process or while delivering the semiconductor chips, semiconductor chip loading trays are employed. 
     Such a semiconductor chip loading tray includes a rectangular frame, a plurality of chip loading recesses arranged in a grid pattern on the top of the frame, and a plurality of semiconductor chip support projections arranged along the periphery of each of the chip loading recesses with a space on all sides, wherein the rectangular semiconductor chips are delivered to a manufacturing line for applying them in a state in which the semiconductor chips are respectively loaded in the chip loading recesses and supported by the support projections. 
     DISCLOSURE OF INVENTION 
     Technical Problem 
     Semiconductor chips are very sensitive electronic parts. With the above-mentioned conventional semiconductor chip tray, semiconductor chips collide with the hard support projections around the chip loading recesses on the frame while the semi-conductor chips are introduced into the chip loading recesses. As a result, the semi-conductor chips are easily damaged. In addition, while being transported after packaged in the final manufacturing line, the semiconductor chips may also be damaged. 
     In addition, if external force is applied to one or more trays while a plurality of trays loaded with semiconductor chips are stacked on a working die, the semiconductor chips may be easily moved out of the chip loading recesses. Therefore, the semi-conductor chips may not be adsorbed by a suction device so well, even if they are loaded on a tray so as to adsorb them at once by the suction device for a subsequent process. Even if the semiconductor chips are adsorbed at once, it is difficult to properly perform the subsequent process because the semiconductor chips are adsorbed in a misaligned state. 
     In addition, trays are typically used in a stacked state rather than individually used. However, in the process of handling such trays, such as loading and transporting the trays, slippage is caused between stacked trays. As a result, various obstructions are caused in a subsequent manufacturing process. 
     Furthermore, after semiconductor chips are loaded on conventional semiconductor chip loading trays, the front side inspection of the semiconductor chips is allowed but the rear side inspection of the semiconductor chips is not possible. That is, if a plurality of trays loaded with semiconductor chips are stacked, a gap is produced between the bottom of an upper tray and the top of an adjacent lower tray, whereby if the trays loaded with the semiconductor chips are turned upside down, the semiconductor chips are moved due to the gaps existing between the trays. 
     More specifically, in the prior art, if a plurality of trays loaded with semiconductor chips are stacked and turned upside down, the semiconductor chips are moved and scratched by the hard trays, thereby rendering the quality of the semiconductor chips poor. Consequently, with the conventional trays, the rear side inspection of semi-conductor chips performed by turning the trays upside down is not possible. 
     Technical Solution 
     Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and the present invention provides a chip scale package tray which is capable of preventing semiconductor chips from being damaged when the chips are loaded on the tray, preventing the semiconductor chips from moving away from predetermined positions while they are loaded on the tray, so that the semiconductor chips can be smoothly adsorbed by a semiconductor chip suction device, preventing an operation line in a manufacturing process from being interrupted, thereby improving work efficiency, preventing slippage between trays when a plurality of trays loaded with semiconductor chips are stacked and handled, and allowing the rear side inspection of the semiconductor chips as well as the front side inspection of the semiconductor chips after the chips are loaded on a plurality of trays, the rear side inspection being performed by turning the trays upside down. 
     ADVANTAGEOUS EFFECTS 
     The present invention, a chip scale tray, has an advantageous effects which is capable of preventing semiconductor chips from being damaged when the chips are loaded on the tray, preventing the semiconductor chips from moving away from pre-determined positions while they are loaded on the tray, so that the semiconductor chips can be smoothly adsorbed by a semiconductor chip suction device, preventing a working line in a manufacturing process from being interrupted, thereby improving work efficiency, preventing slippage between trays when a plurality of trays loaded with semiconductor chips are stacked and handled, and allowing the rear side inspection of the semiconductor chips as well as the front side inspection of the semi-conductor chips after the chips are loaded on the trays, the rear side inspection being performed by turning the trays upside down. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a top side perspective view showing the configuration of the inventive chip scale package tray; 
         FIG. 2  is a bottom side perspective view of the inventive chip scale package tray of  FIG. 1 ; 
         FIG. 3  is a top plan view of the inventive chip scale package tray; and 
         FIG. 4  and  FIG. 5  are cross-sectional views taken along lines A-A and B-B in  FIG. 3 , respectively. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     In accordance with an aspect of the present invention, there is provided a chip scale package tray including: a rectangular frame; a plurality of seat members formed from a material relatively soft and superior in frictional force as compared to the frame, the seat members being arranged on the top of the frame in a grid pattern, a semiconductor chip being loaded on the top of each of the seat members; and a plurality of support members formed from a material relatively soft and superior in frictional force as compared to the frame, the support members being attached to the bottom of the frame to be opposed to the seat members. 
     Each of the seat members, which is formed from a material relatively soft and superior in frictional force as compared to the frame, such as an elastic rubber or silicone, is fabricated to have a configuration having a seat area and a plurality of chip support pieces arranged around the periphery of the seat area. Each of the support members formed from a material relatively soft and superior in frictional force as compared to the frame, such as an elastic rubber or silicone, is fabricated to have a configuration having a semiconductor chip contact area, and a plurality of engagement projections arranged around the periphery of the semiconductor chip contact area. 
     The frame is formed by introducing a synthetic resin into cavities of a first set of molds and curing the synthetic material in the cavities, the seat members are formed by interposing the frame between the cavities of a second set of molds, introducing a material relatively soft and superior in frictional force as compared to the frame between the top of the frame and the cavities of one of the second set of molds in a molten state, and curing the material in the cavities, and the support member is formed by introducing a material relatively soft and superior in frictional force as compared to the frame between the bottom of the frame and the cavities of the other of the second set of molds in a molten state, and curing the material in the cavities, whereby the frame, the seat members and the support members form a triple injection-molded structure. 
     A first set of fastening projections are integrally formed with the respective seat members on the bottom sides of the seat members to be opposed to the seat areas or the chip support pieces, and a first set of fastening holes are formed through the frame, so that the first set of the fastening projections can be fitted in the first set of the fastening holes on the top of the frame. In addition, a second set of fastening projections are integrally formed with the respective support members on the top sides of the support members to be opposed to the semiconductor chip contact areas or engagement projections, and a second set of fastening holes are formed through the frame, so that the second set of the fastening projections can be fitted in the fastening holes on the bottom of the frame. 
     Each of the first set of the fastening projections of the seat members is formed in a cross-sectional shape with the diameter increasing when moving from the bottom end to the top end thereof, while each of the second set of the fastening holes in the frame is formed in a specific shape with the diameter decreasing when moving from the bottom end to the top end thereof. In addition, each of the second set of the fastening projections of the support members is formed in a shape of a circular cross-section with the diameter increasing when moving from the top end to the bottom end thereof, while each of the second set of the fastening holes in the frame is formed in a specific shape with the diameter decreasing when moving from the top end to the bottom end thereof. 
     The seat members and the support members are additionally provided with conductive particles. 
     MODE FOR THE INVENTION 
       FIG. 1  is a top side perspective view showing the configuration of the present invention, and  FIG. 2  is a bottom side perspective view corresponding to  FIG. 1 . In addition,  FIG. 3  is a top plan view, and  FIG. 4  and  FIG. 5  are cross-sectional views taken along lines A-A and B-B in  FIG. 3 , respectively. As shown in the drawings, the inventive chip scale package tray includes a rectangular frame  10  with a plurality of seat members  20  arranged on the top of the frame  10  in a grid pattern, and a plurality of support members  30  arranged on the bottom of the frame  10  in a grid pattern. 
     The frame  10  is fabricated in a rectangular (i.e., right-angled tetragonal) plate shape from a hard synthetic resin. In addition, the peripheral edge of the top of the frame  10  is formed with a rim  11  projecting upward. Referential numeral  13  indicates view windows. 
     The seat members  20  are formed from a material relatively soft and superior in frictional force as compared to the frame  10 . That is, as being formed from a material, such as an elastic rubber, silicone, urethane, etc., that is softer than a conventional hard synthetic resin, thereby being superior in elasticity and frictional force, the seat members  20  are relatively softer than the frame  10 , thereby being superior in frictional force as compared to the frame  10 . 
     At this time, each of the seat members  20  includes a seat area  22  formed in a rectangular shape corresponding to a rectangular semiconductor chip, and a plurality of chip support pieces  24  arranged along the periphery of the seat area  22  (i.e., along the left, right, front and rear edges of the seat area  22 ) to be spaced from each other and integrally molded with the seat area  22 , and a chip mount recess defined by the inner sides of the chip support pieces  24  and the seat area  22 . That is, when a semiconductor chip (not shown) is loaded on a seat area  22  of such a seat member  20 , the chip support pieces  24  support the side areas of the semiconductor chip in such a manner that the semiconductor chip is prevented from moving. The seat member  20  also has fastening projections  26  which are integrally molded on the bottom side of the seat member to be opposed to the seat area  22  or the chip support pieces  24 . In the present embodiment, the fastening projections  26  are formed on the bottom side of the seat member  20  to be opposed to both of the seat area  22  and the chip support pieces  24 . 
     The support members  30  are formed from a material relatively soft and superior in frictional force as compared to the frame  10 . That is, as being formed from a material, such as an elastic rubber, silicone, urethane, etc., that is softer than a conventional hard synthetic resin, thereby being superior in elasticity and frictional force, the support members  30  are relatively softer than the frame  10 , thereby being superior in frictional force as compared to the frame  10 . 
     At this time, each of the support members  30  includes a substantially rectangular semiconductor chip contact area  32 , and a plurality of engagement projections  34  arranged along the periphery of the semiconductor chip contact area  32  to be spaced from each other. In addition, each of the support members  30  also has fastening projections  36  which are integrally molded on and project from the top side of the support member to be opposed to the semiconductor contact area  32  or the engagement projections  34 . In the present embodiment, the fastening projections  36  are formed on and project from the top side of each of the support members to be opposed to both of the semiconductor contact area  32  and the engagement projections  34 . 
     Meanwhile, the frame  10  is formed by introducing a synthetic resin into cavities of a first set of molds and curing the synthetic resin in the cavities, the seat members  20  are formed by interposing the frame  10  between cavities of a second set of molds, introducing a soft and frictional material (a first material) between the cavities of one of the second set of molds and the top of the frame  10  in a molten state, and curing the material in the cavities, and the support member  30  is formed by introducing a soft and frictional material (a second material) between the cavities of the other of the second set of molds and the bottom of the frame  10  in a molten state, and curing the material in the cavities. 
     That is, the frame  10  is molded by introducing an ordinary synthetic resin into the cavities of the first set of molds and curing the synthetic resin in the cavities. Next, in a state in which the frame  10  is interposed between the cavities of the second set of molds, a soft and frictional material, such as an elastic rubber, silicone, and urethane is introduced in a molten state and cured between the top of the frame  10  and the cavities of one of the second set of molds through runners (runners communicating with cavities arranged in a grid pattern having negative shapes for the seat members  20  to be formed on the top of the frame  10 ), so that the soft and frictional seat members  20  can be integrally molded on the top of the frame  10  in the grid pattern. 
     At the same time, a soft and frictional material, such as an elastic rubber, silicone, and urethane, is introduced in a molten state and cured between the bottom of the frame  10  and the cavities of the other of the second set of molds through runners (runners communicating with cavities having negative shapes for the support members  30  and arranged in a grid pattern), so that the soft and frictional support members  30  can be integrally molded on the bottom of the frame  10  in the grid pattern. 
     As a result, according to the present invention, there is provided a chip scale package tray with a triple injection-molded structure, wherein seat members  20  which are relatively soft and superior in frictional force as compared to the frame  10  are integrally molded on the top of the frame  10  in a grid pattern, and support members  30  which are relatively soft and superior in frictional force as compared to the frame  10  are integrally molded on the bottom of the frame  10  at the positions corresponding to those of the seat members  20  in a grid pattern. 
     Each of the seat members  20  has a plurality of chip support pieces  24  arranged along and upwardly projecting from the periphery of a rectangular seat area  22 , and a plurality of fastening projections  26  integrally molded on the bottom side of the seat member to be opposed to the seat area  22  and the chip support pieces  24 . Fastening holes  16  corresponding to the fastening projections  26  are formed through the frame  10  from the top of the frame  10 , so that the fastening projections  16  on the bottom sides of the seat members  20  are fitted in the fastening holes  16  in the frame  10 , respectively. 
     That is, because the frame  10 , the seat members  20  and the support members  30  are fabricated in a triple injection-molded structure, the fastening projections  26  on the bottom sides of the seat members  20  are formed by being automatically filled in the fastening holes  16  of the frame  10  during the process of triple injection-molding. Consequently, the bottom sides of the seat members  20  are automatically fastened to the top of the frame  10 . 
     In addition, each of the support members  30  has a plurality of engagement projections  34  arranged along and downwardly projecting from the periphery of a rectangular semiconductor chip contact area  32 , and a plurality of fastening projections  36  integrally molded on the top side of each support member to be opposed to the semiconductor chip contact area  32  and the engagement projections  34 . Fastening holes  18  corresponding to the fastening projections  36  of the support members  30  are formed through the frame  10  from the top of the frame  10 , so that the fastening projections  36  on the top sides of the support members  30  are fitted in the fastening holes  18  in the frame  10 , respectively. 
     That is, because the frame  10 , the seat members  20 , and the support members  30  are fabricated in a triple injection-molded structure, the fastening projections  36  on the top sides of the support members  30  are formed by being automatically filled in the fastening holes  16  of the frame  10  during the process of triple injection molding. Consequently, the top sides of the seat members  30  are automatically fastened to the bottom of the frame  10 . 
     Therefore, if and when semiconductor chips are loaded on the seat members  20  of the inventive chip scale package tray, respectively, a plurality of such semiconductor chip loading trays are stacked and transported, operation is performed using the package trays, and the support members  30  on the bottom of an upper tray compress the top of the semiconductor chips loaded on the seat members  20  of a lower tray adjacent to the upper tray. 
     In that event, because the seat members  20  and the support members  30  are formed from a material relatively soft and superior in frictional force as compared to the frame  10  formed from a conventional synthetic resin, it is possible to prevent semiconductor chips from being easily damaged in the course of loading the semiconductor chips on the seat members  20 . That is, even if the semiconductor chips bump against the upwardly projecting chip support pieces  24  in the course of loading the semiconductor chips on the seat areas  22  of the seat members  20 , the seat members  20  dampen the shock applied to the semiconductor chips because the seat members  20  are formed from a material relatively soft as compared to the hard frame  10 , whereby it is possible to prevent the semiconductor chips, which are sensitive to shock, from being easily damaged in the course of loading the semiconductor chips. 
     In addition, because the seat members  20  are formed from a material relatively soft and thus superior in frictional force as compared to the frame  10 , the semiconductor chips are not removed so easily from the seat members  20  (i.e., from the semi-conductor chip loading recesses) by external force applied while handling the semi-conductor chip loading trays so as to stack the trays on a working die in a manufacturing line. As a result, it is possible to allow a semiconductor chip suction device to adsorb and remove all the semiconductor chips from a tray at once for the subsequent manufacturing process, whereby the subsequent manufacturing process can be smoothly performed. 
     In addition, because the support members  30  as well as the seat members  20  are formed from a material relatively soft and thus superior in frictional force as compared to the frame  10 , slippage does not occur between the trays in the course of transporting a plurality of stacked trays or performing other operations. As a result, it is possible to prevent in advance various obstructions which may be caused in a fabricating process. 
     In addition, even if semiconductor chips are moved due to gaps produced between adjacent trays when a plurality of trays are turned upside down in a state in which semiconductor chips are loaded on the trays, the semiconductor chips come into contact with the soft and frictional support members  30 . As a result, it is possible to prevent the semiconductor chips from being scratched, rendering the quality of the semiconductor chips poor. Furthermore, due to this feature, it is possible to inspect the rear sides of the semiconductor chips by turning the trays upside down. 
     Meanwhile, each of the fastening projections  26  formed on and projecting from the bottom sides of the seat members  20  has a cross-sectional shape with the diameter increasing when moving from the top to bottom thereof, and each of the upper fastening holes  16  of the frame  10 , in which the fastening projections  26  are fitted, respectively, is formed in a specific shape with the diameter decreasing when moving from the bottom to top thereof. As a result, because the fastening projections  26  on the bottom sides of the seat members  26  do not get out of the upper fastening holes  16  of the frame  10  so easily, unless the seat members  20  are forcibly separated from the top of the frame  10 , it is possible to increase the fastening engagement force between the seat members  20  and the frame  10 . 
     In addition, each of the fastening projections  36  formed on and projecting from the top sides of the support members  30  has a cross-sectional shape with the diameter decreasing when moving from the top to bottom thereof, and each of the lower fastening holes  18  of the frame  10 , in which the fastening projections  36  are fitted, respectively, is formed in a specific shape with the diameter decreasing when moving from the top to bottom thereof. As a result, because the fastening projections  36  on the top sides of the support members  36  do not get out of the upper fastening holes  16  of the frame  10  so easily, unless the support members  30  are forcibly separated from the bottom of the frame  10 , it is possible to increase the fastening engagement force between the support members  20  and the frame  10 . 
     Furthermore, the seat members  20  and the support members  30  are additionally provided with a plurality of conductive particles  40 . Therefore, even if static electricity is produced when a plurality of trays loaded with semiconductor chips are handled, the static electricity flows to the outside of the semiconductor chips through the conductive particles  40  without affecting the semiconductor chips. As a result, it is possible to prevent the semiconductor chips from being damaged by static electricity. 
     As described above, according to the present invention, the seat members on which semiconductor chips are loaded, and the support members which come into contact with the top surfaces of the semiconductor chips, are formed from a material relatively soft and thus superior in frictional force as compared to the frame formed from a conventional synthetic resin. As a result, it is possible to prevent semiconductor chips from being easily damaged in the course of loading the semiconductor chips on the seat members. In addition, the semiconductor chips are not removed from the seat members so easily by external force applied in the course of handling the semi-conductor chips loaded on the tray for a subsequent process. As a result, it is possible for a semiconductor chip suction device to adsorb and remove all the semiconductor chips at once from the tray. Due to this feature, subsequent semiconductor manufacturing processes can be smoothly performed. 
     In addition, according to the present invention, the seat members and the support members are formed from a rubber which is soft and thus superior in frictional force. Therefore, while transporting a plurality of stacked trays or performing any other operation, no slippage occurs between the trays. Consequently, it is possible to prevent in advance various obstructions which may be caused in manufacturing processes. 
     Moreover, even if semiconductor chips are moved due to gaps produced between adjacent trays when a plurality of trays are turned upside down in a state in which semiconductor chips are loaded on the trays, the semiconductor chips come into contact with the soft and frictional support members. As a result, it is possible to prevent the semiconductor chips from being scratched, rendering the quality of the semiconductor chips poor. Furthermore, due to this feature, it is possible to inspect the rear sides of the semiconductor chips by turning the trays upside down. 
     While the present invention has been described with reference to the particular illustrative embodiments, it is not to be restricted by the embodiments but only by the appended claims, and therefore, it is to be understood that other modifications and variations may be made without departing from the substance and scope of the present invention, as those skilled in the art will readily understand. Such alternate modifications and variations are within the scope of the present invention which is intended to be limited only by the appended claims and equivalents thereof. 
     INDUSTRIAL APPLICABILITY 
     The present invention, a chip scale tray, has an industrial applicability for preventing semiconductor chips from being damaged when the chips are loaded on the tray, preventing the semiconductor chips from moving away from predetermined positions while they are loaded on the tray. Therefore, the semiconductor chips can be smoothly adsorbed by a semiconductor chip suction device, preventing a working line in a manufacturing process from being interrupted, thereby improving work efficiency, preventing slippage between trays when a plurality of trays loaded with semiconductor chips are stacked and handled, and allowing the rear side inspection of the semi-conductor chips as well as the front side inspection of the semiconductor chips after the chips are loaded on the trays, the rear side inspection being performed by turning the trays upside down.