Manufacturing method of semiconductor package

Abstract

The present invention discloses a method for manufacturing a semiconductor package comprising examining the structure and material of a substrate, estimating an error in a solder ball attachment process, determining the specifications of a ball tool and the method of the solder ball attachment process according to the estimated error, manufacturing the ball tool, and performing the solder ball attachment process, wherein the substrate comprises a plurality of work areas, and determining the specifications of the ball tool and the method of the solder ball attachment process comprises determining the number of holders of the ball tool, the position and width of the holders, and determining the number of work areas, the position and width of each of the work areas.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing a semiconductor package, and more specifically, to a method for manufacturing a semiconductor package comprising a solder ball attach process. Background Technology

[0003] A semiconductor package is an integrated circuit chip implemented in a form suitable for use in electronic products. Typically, semiconductor packages are created by mounting a semiconductor chip onto a substrate, such as a printed circuit board (PCB). Solder balls may be used to electrically connect internal circuits to the outside. Solder balls can be formed on the surface of the substrate and electrically connected to exposed pads. With the recent advancement of the electronics industry, there is an increasing demand for high functionality, high speed, and miniaturization of electronic components. Due to this trend, the size of solder balls is also becoming finer. The problem to be solved

[0005] One technical problem of the present invention is to provide a method for manufacturing a semiconductor package with improved reliability and electrical characteristics.

[0006] The problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0008] To solve the aforementioned technical problems, a method for manufacturing a semiconductor package according to embodiments of the present invention comprises examining the structure and material of a substrate, estimating an error in the solder ball attachment process, determining the specifications of a ball tool and the method of the solder ball attachment process according to the estimated error, manufacturing the ball tool, and performing the solder ball attachment process, wherein the substrate includes a plurality of work areas, and determining the specifications of the ball tool and the method of the solder ball attachment process may include determining the number of holders of the ball tool, the position and width of the holders, and determining the number of work areas, the position and width of each of the work areas.

[0009] Additionally, a method for manufacturing a semiconductor package according to embodiments of the present invention comprises mounting a semiconductor chip on a first surface of a substrate, forming pads on a second surface of the substrate opposite to the first surface, and forming solder balls on the pads, wherein forming the solder balls includes examining the structure and material of the substrate, estimating an error in the solder ball attachment process, determining the specifications of a ball tool and the method of the solder ball attachment process according to the estimated error, manufacturing the ball tool, performing the solder ball attachment process, and verifying the ball tool, wherein the substrate includes a first work area and a second work area, and the ball tool may include a first holder on a first tool area corresponding to the first work area and a second holder on a second tool area corresponding to the second work area. Effects of the invention

[0011] According to the method for manufacturing a semiconductor package of the present invention, by dividing the working areas of a substrate by anticipating the error of the solder ball attachment process, manufacturing a ball tool accordingly, and performing a plurality of solder ball attachment processes for each divided working area, the solder balls can be accurately placed on the center of each pad on the substrate (i.e., the alignment error between the solder balls and the pads can be prevented and / or minimized), and accordingly, the reliability and electrical characteristics of the semiconductor package can be improved. Brief explanation of the drawing

[0013] FIGS. 1a and FIGS. 1b are flowcharts illustrating a method for manufacturing a semiconductor package according to embodiments of the present invention. FIG. 2a is a plan view illustrating a substrate used in a method for manufacturing a semiconductor package according to embodiments of the present invention. FIG. 2b is a cross-sectional view for illustrating a substrate used in a method for manufacturing a semiconductor package according to embodiments of the present invention, corresponding to a cross-section of FIG. 2a cut along the line I-I'. FIGS. 3a to 3d are cross-sectional views illustrating a ball tool used in a method for manufacturing a semiconductor package according to embodiments of the present invention. FIGS. 4a, FIGS. 4b, and FIGS. 4c are conceptual diagrams for explaining the estimation of an error in the solder ball attach process among the manufacturing methods of a semiconductor package according to embodiments of the present invention. FIGS. 5A, FIGS. 5B, FIGS. 5C, FIGS. 5D, and FIGS. 5E are cross-sectional views illustrating the performance of a solder ball attach process among the manufacturing methods of a semiconductor package according to embodiments of the present invention. FIG. 6a is a plan view illustrating a substrate used in a method for manufacturing a semiconductor package according to embodiments of the present invention. FIGS. 6b and FIGS. 6c are cross-sectional views illustrating the solder ball attach process among the manufacturing methods of a semiconductor package according to embodiments of the present invention. Specific details for implementing the invention

[0014] Hereinafter, a method for manufacturing a semiconductor package according to embodiments of the present invention will be described in detail with reference to the drawings.

[0016] FIGS. 1a and FIGS. 1b are flowcharts illustrating a method for manufacturing a semiconductor package according to embodiments of the present invention.

[0017] Referring to FIG. 1a, a method for manufacturing a semiconductor package according to the present invention may include mounting a semiconductor chip on a first surface of a substrate (S10), forming a pad on a second surface of the substrate (S20), and forming a solder ball on the pad (S30). The second surface of the substrate may be a surface facing the first surface. The pad and the solder ball may be formed of a conductive material. According to embodiments, a method for manufacturing a semiconductor package according to the present invention may further include applying a flux on the second surface of the substrate prior to forming the pad (S20).

[0018] Referring to FIG. 1b, forming a solder ball (S30) in the method for manufacturing a semiconductor package according to the present invention may include examining the structure and material of a substrate (S100), estimating an error in the solder ball attach process (S200), determining the specifications of a ball tool and the method of the solder ball attach process (S300), manufacturing a ball tool (S400), performing the solder ball attach process (S500), verifying the ball tool according to the result of the solder ball attach process (S600), and storing the verification data on a server (S700).

[0019] Errors in the solder ball attach process may include, for example, misalignment between the substrate and the ball tool due to expansion / contraction of the substrate and driving errors of the ball tool.

[0020] Determining the specifications of the ball tool and the method of the solder ball attach process (S300) may include determining the number of ball tool holders, the position and width of each holder, and determining the number of work areas of the substrate, the position and width of each work area. The number of ball tool holders may be less than or equal to the number of work areas. The number of ball tool holders may be, for example, equal to the number of work areas divided by an integer greater than or equal to 2.

[0021] The result of verifying the ball tool (S600) can be reflected in calculating the error of the solder ball attachment process (S200) in the solder ball attachment process for another substrate.

[0022] The verification data stored on the server can be reflected in determining the specifications of the ball tool and the method of the solder ball attachment process (S300) in the solder ball attachment process for another substrate.

[0024] FIG. 2a is a plan view illustrating a substrate used in a method for manufacturing a semiconductor package according to embodiments of the present invention. FIG. 2b is a cross-sectional view illustrating a substrate used in a method for manufacturing a semiconductor package according to embodiments of the present invention, corresponding to a cross-section of FIG. 2a cut along the line I-I'.

[0025] Referring to FIGS. 2a and 2b, a semiconductor chip, a molding film, and wiring may be provided on a first surface (100a) of a substrate (100). A plurality of pads (110) and insulating patterns (130) may be provided on a second surface (100b) of the substrate (100) facing the first surface (100a) in a third direction (D3). Each of the first surface (100a) and the second surface (100b) of the substrate (100) may be a plane parallel to the first direction (D1) and the second direction (D2), and orthogonal to the third direction (D3). The first to third directions (D1, D2, D3) may be directions orthogonal to each other.

[0026] Pads (110) may be arranged along a first direction (D1) and a second direction (D2). More specifically, the pads (110) may be arranged in an array form including a plurality of rows extending in the first direction (D1) and spaced apart from each other in the second direction (D2), and a plurality of columns extending in the second direction (D2) and spaced apart from each other in the first direction (D1). The number of rows and columns is not limited to that illustrated. The pads (110) may be electrically connected to semiconductor chips and / or wiring on the first surface (100a).

[0027] Insulating patterns (130) can fill the space between the pads (110). A portion of each insulating pattern (130) may cover a portion of the upper surface of each pad (110), but the invention is not limited thereto.

[0028] Work areas of the substrate (100) can be determined by determining the method of the solder ball attach process (S300, see FIG. 1b). For example, the substrate (100) may include a first work area (R1), a second work area (R2), a third work area (R3), and a fourth work area (R4). The first work area (R1) and the second work area (R2) may be spaced apart from each other in a first direction (D1). The third work area (R3) may be located between the first work area (R1) and the second work area (R2). The fourth work area (R4) may be located between the first work area (R1) and the third work area (R3).

[0029] The width of the first work area (R1) in the first direction (D1) may differ from the width of the second work area (R2) in the first direction (D1). The width of the first work area (R1) in the first direction (D1) may be substantially the same as the width of the third work area (R3) in the first direction (D1). The width of the second work area (R2) in the first direction (D1) may be substantially the same as the width of the fourth work area (R4) in the first direction (D1).

[0030] The number of work areas of the substrate (100), the location and width of each work area may vary depending on the result of estimating the error of the solder ball attach process (S200, see FIG. 1b) and are not limited to those illustrated. For example, the substrate (100) may include four or more work areas, and the work areas of the substrate (100) may all have the same width.

[0031] In order to determine the specifications of the ball tool and the method of the solder ball attachment process (S300, see FIG. 1b), the first end (R1e1) and the second end (R1e2) of the first work area (R1), the first end (R2e1) and the second end (R2e2) of the second work area (R2), the first end (R3e1) and the second end (R3e2) of the third work area (R3), and the first end (R4e1) and the second end (R4e2) of the fourth work area (R4) can be recognized by a pattern recognition system (PRS). Each of the ends of the work areas can be defined as the side wall of the pad (110) of each of the work areas located on the outer side.

[0033] FIGS. 3a to 3d are cross-sectional views illustrating a ball tool used in a method for manufacturing a semiconductor package according to embodiments of the present invention. In describing with reference to FIGS. 3b, 3c, and 3d respectively, descriptions of matters substantially identical to those described with reference to FIG. 3a are omitted, and the differences are described in detail.

[0034] Referring to FIG. 3a, the ball tool (200) may include a housing (210), a first drive unit (221), a second drive unit (222), a first holder (H1), and a second holder (H2). The ball tool (200) may include a first tool area (TR1) provided with the first drive unit (221) and the first holder (H1), a second tool area (TR2) provided with the second drive unit (222) and the second holder (H2), and a third tool area (TR3) between the first tool area (TR1) and the second tool area (TR2). The width of the first tool area (TR1) in the first direction (D1) may differ from the width of the second tool area (TR2) in the first direction (D1). For example, the width of the first tool area (TR1) in the first direction (D1) may be greater than the width of the second tool area (TR2) in the first direction (D1).

[0035] A first space (S1) enclosed by a first side wall (210s1) of the housing (210) and a first partition (210p1) inside the housing (210) may be provided within the first tool area (TR1). A first drive unit (221) and a first holder (H1) may be provided within the first space (S1). Although the first side wall (210s1) of the housing (210) is shown to have a step in one area, this is merely exemplary and the shape of the first side wall (210s1) of the housing (210) is not limited to that shown.

[0036] The first drive unit (221) may include a first drive member (2211) and a first drive shaft (2213). The first drive member (2211) may be configured to move the first drive shaft (2213) in a third direction (D3). For example, the first drive member (2211) may include a hydraulic cylinder, a motor, etc. The first drive shaft (2213) extends in the third direction (D3) and may be connected to the first holder (H1). The first drive shaft (2213) may move in the third direction (D3) by the power transmitted by the first drive member (2211). Depending on the first drive shaft (2213), the first holder (H1) may also move in the third direction (D3).

[0037] The first holder (H1) may include a pressing plate (230) coupled to the first driving member (2211) of the first driving unit (221), pins (240) below the pressing plate (230), a suction plate (250) having suction holes (250h) connected to the housing (210) and configured to allow the pins (240) to move, and a guide member (260) configured to guide the movement path of solder balls below the suction plate (250).

[0038] The pressing plate (230) and the pins (240) can be moved in a third direction (D3) by the first driving unit (221), and the pins (240) can be moved into the suction holes (250h). The size of the pressing plate (230) (i.e., width in the first direction (D1) and thickness in the third direction (D3)) and the position of each pin (240) (i.e. position inside the suction holes (250h)) can be adjusted as needed.

[0039] The inner wall (251s1) of the suction plate (250) defining the suction holes (250h) may be an inclined surface having an inclination with respect to the third direction (D3). The outer wall (251s2) of the suction plate (250) may be a surface parallel to the third direction (D3). In other words, the outer wall (251s2) of the suction plate (250) may be orthogonal to the lower surface of the second part (252) of the suction plate (250).

[0040] A second space (S2) enclosed by a second side wall (210s2) of the housing (210) and a second partition (210p2) inside the housing (210) may be provided within the second tool area (TR2). A second drive unit (222) and a second holder (H2) may be provided within the second space (S2). Although the second side wall (210s2) of the housing (210) is shown to have a step in one area, this is merely exemplary and the shape of the second side wall (210s2) of the housing (210) is not limited to what is shown.

[0041] The second drive unit (222) may include a second drive member (2221) and a second drive shaft (2223). The second drive member (2221) and the second drive shaft (2223) of the second drive unit (222) may have substantially the same structure as the first drive member (2211) and the first drive shaft (2213) of the first drive unit (221).

[0042] The second holder (H2) may have a structure substantially identical to that of the first holder (H1). However, the width of the second holder (H2) in the first direction (D1) may differ from the width of the first holder (H1) in the first direction (D1). For example, the width of the second holder (H2) in the first direction (D1) may be smaller than the width of the first holder (H1) in the first direction (D1). However, this is merely illustrative and the present invention is not limited thereto, and the width of the first holder (H1) in the first direction (D1) may be substantially the same as the width of the second holder (H2) in the first direction (D1).

[0043] The suction plate (250) may include a first portion (251) provided on a first tool area (TR1) (or a second tool area (TR2)), and a second portion (252) provided on a third tool area (TR3) and extending from the first portion (251) in a first direction (D1). The lower surface of the first portion (251) and the lower surface of the second portion (252) may be located at different levels. More specifically, the lower surface of the first portion (251) and the lower surface of the second portion (252) may have a height difference (HD), and the height difference (HD) may be, for example, about 150 μm to about 250 μm.

[0044] A third space (S3) surrounded by a first partition (210p1) and a second partition (210p2) inside the housing (210) may be provided within the third tool area (TR3). A second part (252) of a suction plate (250) may be provided at the bottom of the third space (S3). A driving unit and a holder may not be provided inside the third space (S3), but the present invention is not limited thereto.

[0045] The first tool area (TR1) of the ball tool (200) may correspond to the first work area (R1) and the third work area (R3) of the substrate (100) described with reference to FIGS. 2a and 2b. More specifically, the width of the first holder (H1) of the first tool area (TR1) in the first direction (D1) may be substantially the same as the width of the first work area (R1) and the third work area (R3) of the substrate (100) in the first direction (D1), respectively. Additionally, the second tool area (TR2) of the ball tool (200) may correspond to the second work area (R2) and the fourth work area (R4) of the substrate (100) described with reference to FIGS. 2a and 2b. More specifically, the width of the second holder (H2) of the second tool area (TR2) in the first direction (D1) may be substantially the same as the width of the second work area (R2) and the fourth work area (R4) of the substrate (100) in the first direction (D1), respectively.

[0046] According to embodiments, the ball tool (200) may further include heating / cooling units configured to independently control the temperature of the area below each of the first to third tool regions (TR1, TR2, TR3). The heating / cooling units may be provided at positions corresponding to each of the first to third tool regions (TR1, TR2, TR3).

[0047] The ball tool (200) may have different structures and shapes depending on the error of the solder ball attachment process (S200, see FIG. 1b) and the specification of the ball tool and the method of the solder ball attachment process (S300), and the position of the ends of the work areas recognized by the pattern recognition system (PRS).

[0048] Referring to FIG. 3b, the outer wall (251s2) of the suction plate (250) may be an inclined surface having a slope with respect to the third direction (D3). The slope of the outer wall (251s2) of the suction plate (250) with respect to the third direction (D3) may be different from the slope of the inner wall (251s1) of the suction plate (250) with respect to the third direction (D3). For example, the slope of the outer wall (251s2) of the suction plate (250) with respect to the third direction (D3) may be smaller than the slope of the inner wall (251s1) of the suction plate (250) with respect to the third direction (D3).

[0049] Referring to FIG. 3c, a portion of the outer wall (251s2) of the suction plate (250) may be an inclined surface having an inclination with respect to the third direction (D3). Another portion of the outer wall (251s2) of the suction plate (250) may be a surface parallel to the third direction (D3). The inclination of the portion of the outer wall (251s2) of the suction plate (250) with respect to the third direction (D3) may be substantially the same as the inclination of the inner wall (251s1) of the suction plate (250) with respect to the third direction (D3).

[0050] Referring to FIG. 3d, a third space (S3) surrounded by first and second partitions (210p1, 210p2) inside the housing (210) may be provided within the third tool area (TR3), and a third drive unit (223) and a third holder (H3) may be provided within the third space (S3). The width of the third holder (H3) in the first direction (D1) may differ from the width of each of the first and second holders (H1, H2) in the first direction (D1).

[0051] The third drive unit (223) may include a second drive member (2231) and a second drive shaft (2233). The second drive member (2231) and the second drive shaft (2233) of the second drive unit (223) may have substantially the same structure as the drive member and drive shaft of the first drive unit (221) and the second drive unit (222), respectively. Each of the first to third drive units (221, 222, 223) may be controlled independently of each other. Although each of the first to third drive units (221, 222, 223) is illustrated as being located on the central axis of each of the first to third holders (H1, H2, H3), this is merely exemplary, and the location of each of the first to third drive units (221, 222, 223) connected to each of the first to third holders (H1, H2, H3) is not limited to what is illustrated.

[0053] FIGS. 4a, FIGS. 4b, and FIGS. 4c are conceptual diagrams for explaining the estimation of an error in the solder ball attach process among the manufacturing methods of a semiconductor package according to embodiments of the present invention.

[0054] Referring to FIG. 4a, the first ball image (B1) and the second ball image (B2) may be virtual ball images for calculating the first error (a1). The radius of the first ball image (B1) and the radius of the second ball image (B2) may be the same. The first ball image (B1) may have a spherical shape with the first axis (AX1) as the central axis, and the second ball image (B2) may have a spherical shape with the second axis (AX2) as the central axis. The first axis (AX1) may coincide with the central axis of the pad (110) and the central axis of the auxiliary pad (120), and the second axis (AX2) may be spaced apart from the first axis (AX1) by the first error (a1) in the first direction (D1). The second ball image (B2) may come into contact with the vertex (130v) of the insulation pattern (130).

[0055] At this time, the first error (a1) can be defined as the distance between the center (B1c) of the first ball image (B1) and the center (B2c) of the second ball image (B2), and can be calculated by the following [Equation 1]. The first error (a1) is the allowable error of the solder ball position for electrical connection between the solder ball and the pad (110).

[0056] [Mathematical Formula 1]

[0057]

[0058] At this time, X is the distance in the first direction (D1) between the first axis (AX1) and the side wall (130s) of the insulation pattern (130), R is the radius of each of the first and second ball images (B1, B2), T2 is the height difference in the third direction (D3) between the upper surface (130t) of the insulation pattern (130) and the upper surface (110t) of the pad (110), and T1 is the height difference in the third direction (D3) between the upper surface (120t) of the auxiliary pad (120) and the upper surface (110t) of the pad (110).

[0059] Referring to FIG. 4b, the first sidewall (100s1) of the substrate (100) may be spaced apart from the first sidewall (210s1) of the housing (210) of the ball tool (200) by a first offset (a21) in the first direction (D1). The second sidewall (100s2) of the substrate (100) may be spaced apart from the second sidewall (210s2) of the housing (210) of the ball tool (200) by a second offset (a22) in the first direction (D1). At this time, the first sidewall (210s1) and the second sidewall (210s2) of the housing (210) of the ball tool (200) may be measured based on the portion aligned with the outer wall of the suction plate (250). The second error (a2) may be defined as the average of the first offset (a21) and the second offset (a22).

[0060] A substrate (100) in which the die bonding process (i.e., mounting a semiconductor chip on the substrate (100) (S10, see FIG. 1a)) and the solder ball attach process are completed may expand / contract due to various heat treatment processes, and accordingly, misalignment may occur between the substrate (100) and the ball tool (200). In addition, a dispersion of width in the first direction (D1) may occur in the plurality of substrates (100) in which the solder ball attach process is performed. That is, the second error (a2) may be an error caused by the misalignment between the substrate (100) and the ball tool (200) due to expansion / contraction and the dispersion of the plurality of substrates (100).

[0061] Referring to FIG. 4c, the ball tool (200) moves in a first direction (D1) for the solder ball attachment process, at which time a third error (a3) ​​may occur. The third error (a3) ​​can be defined as the distance between the center axis (110AX) of any one of the pads (110) and the center axis (240AX) of the corresponding pin (240) of the first holder (H1). Each solder ball (B) can move in a third direction (D3) along the center axis (240AX) of each pin (240) and can be attached at a position offset by the third error (a3) ​​from the center axis (110AX) of each pad (110). That is, the third error (a3) ​​may be an error caused by misalignment between the substrate (100) and the ball tool (200) due to the driving error of the ball tool (200).

[0062] Referring to FIG. 1b, FIG. 4a, FIG. 4b and FIG. 4c, estimating the error of the solder ball attach process (S200) may involve estimating and / or calculating the first to third errors (a1, a2, a3). Determining the specifications of the ball tool (200) and the method of the solder ball attach process (S300) may include determining whether the first to third errors (a1, a2, a3) satisfy the following [Equation 2].

[0063] [Mathematical Formula 2]

[0064] a1 > a2+a3

[0065] More specifically, if [Equation 2] is not satisfied (i.e., if the first error (a1) is less than or equal to the sum of the second error (a2) and the third error (a3)), the working areas of the substrate (100) can be further subdivided, and the structure of the tool areas and holders of the ball tool (200) can be redesigned to fit the subdivided working areas.

[0066] Additionally, determining the specifications of the ball tool (200) and the method of the solder ball attachment process (S300) may include determining the number of solder ball attachment processes (i.e., the number of work areas) by comparing the first error (a1) with the estimated expansion / contraction of the substrate (100). More specifically, the number of solder ball attachment processes n may be determined by the following [Equation 3].

[0067] [Mathematical Formula 3]

[0068] n=[(Expected expansion / contraction of the substrate) / (First error (a1))], (where [x] represents the greatest integer function, which is the largest integer not exceeding x for a real number x)

[0069] According to the embodiments, the number of solder ball attachment processes n may be [(expected expansion / shrinkage of the substrate) / (first error (a1))]+1 (times).

[0071] FIGS. 5A, FIGS. 5B, FIGS. 5C, FIGS. 5D, and FIGS. 5E are cross-sectional views illustrating the performance of a solder ball attach process among the manufacturing methods of a semiconductor package according to embodiments of the present invention.

[0072] Referring to FIG. 5a, solder balls (B) can be accommodated within the adsorption holes (250h) of the adsorption plate (250) of the ball tool (200). The solder balls (B) are adsorbed within the adsorption holes (250h) by the pressure difference between the first space (S1) and the second space (S2) and the outside, respectively, and can come into contact with the inner wall (251s1) of the adsorption plate (250).

[0073] Adsorbing solder balls (B) into the adsorption holes (250h) may, for example, include flipping the ball tool (200) so that the lower surface (200b) of the ball tool (200) faces the third direction (D3), providing vacuum pressure in the first space (S1), the second space (S2), and the adsorption holes (250h) connected thereto by a vacuum pump, and moving (i.e., dropping) the solder balls (B) from the ball feeder into the adsorption holes (250h).

[0074] Adsorbing solder balls (B) into adsorption holes (250h) may, as another example, include positioning a ball tool (200) on a ball jumping device including a vibrating vessel, providing vacuum pressure in a first space (S1), a second space (S2), and adsorption holes (250h) connected thereto by a vacuum pump, and vibrating the vibrating vessel to move the solder balls (B) into the adsorption holes (250h).

[0075] Referring to FIG. 5b, a first solder ball attachment process can be performed on a first work area (R1) of a substrate (100). The first solder ball attachment process can be performed by moving the ball tool (200) in a first direction (D1) so that the first tool area (TR1) of the ball tool (200) overlaps with the first work area (R1) of the substrate (100) in a third direction (D3), and by driving the first driving unit (221) to move the pressing plate (230) and pins (240) of the first holder (H1) downward. Accordingly, solder balls (B) can be attached to the pads (110) of the first work area (R1).

[0076] During the first solder ball attach process, the fourth work area (R4) of the substrate (100) adjacent to the first work area (R1) in the first direction (D1) may not overlap with the ball tool (200) in the third direction (D3). While the first solder ball attach process is being performed, the temperature of the first work area (R1) may differ from the temperatures of the second, third, and fourth work areas (R2, R3, R4).

[0077] Referring to FIG. 5c, a second solder ball attachment process can be performed on a second work area (R2) of a substrate (100). The second solder ball attachment process can be performed by moving the ball tool (200) in a first direction (D1) so that the second tool area (TR2) of the ball tool (200) overlaps with the second work area (R2) in a third direction (D3) after the first solder ball attachment process, and by driving the second drive unit (222) to move the pressing plate (230) and pins (240) of the second holder (H2) downward. Accordingly, solder balls (B) can be attached to the pads (110) of the second work area (R2).

[0078] During the second solder ball attach process, the third work area (R3) of the substrate (100) adjacent to the second work area (R2) in the first direction (D1) may not overlap with the ball tool (200) in the third direction (D3). While the second solder ball attach process is being performed, the temperature of the second work area (R2) may differ from the temperatures of the first, third, and fourth work areas (R1, R3, R4).

[0079] Referring to FIG. 5d, a third solder ball attachment process can be performed on a third working area (R3) of a substrate (100). The third solder ball attachment process can be performed by adsorbing solder balls (B) into the adsorption holes (250h) again after the second solder ball attachment process, moving the ball tool (200) in a first direction (D1) so that the first tool area (TR1) of the ball tool (200) overlaps with the third working area (R3) of the substrate (100) in a third direction (D3), and driving the first driving unit (221) to move the pressing plate (230) and pins (240) of the first holder (H1) downward. Accordingly, solder balls (B) can be attached to the pads (110) of the third working area (R3).

[0080] During the third solder ball attachment process, the third tool area (TR3) of the ball tool (200) and the second part (252) of the suction plate (250) may overlap with the fourth work area (R4) and the first work area (R1) of the substrate (100) in the third direction (D3). At this time, due to the height difference (HD) between the lower surface of the first part (251) of the suction plate (250) and the lower surface of the second part (252), the solder balls (B) already attached to the first work area (R1) may be separated from the lower surface (200b) of the ball tool (200) in the third direction (D3) and may be free from the influence of the ball tool (200) approaching the substrate (100). During the third solder ball attach process, the temperature of the third work area (R3) may differ from the temperatures of the first, second, and fourth work areas (R1, R2, R4).

[0081] Referring to FIG. 5e, a fourth solder ball attachment process can be performed on a fourth work area (R4) of a substrate (100). The fourth solder ball attachment process can be performed by moving the ball tool (200) in a first direction (D1) so that the second tool area (TR2) of the ball tool (200) overlaps with the fourth work area (R4) in a third direction (D3) after the third solder ball attachment process, and by driving the second drive unit (222) to move the pressing plate (230) and pins (240) of the second holder (H2) downward. Accordingly, solder balls (B) can be attached to the pads (110) of the fourth work area (R4).

[0082] During the fourth solder ball attachment process, the third tool area (TR3) of the ball tool (200) and the second part (252) of the suction plate (250) may overlap with the third work area (R3) and the second work area (R2) of the substrate (100) in the third direction (D3). At this time, due to the height difference (HD) between the lower surface of the first part (251) of the suction plate (250) and the lower surface of the second part (252), the solder balls (B) already attached to the second work area (R2) and the third work area (R3) may be separated from the lower surface (200b) of the ball tool (200) in the third direction (D3) and may be free from the influence of the ball tool (200) approaching the substrate (100). During the fourth solder ball attach process, the temperature of the fourth work area (R4) may differ from the temperatures of the first, second, and third work areas (R1, R2, R3).

[0083] However, the number of solder ball attach processes, the number of work areas, and the process sequence for the work areas described with reference to FIGS. 5a, 5b, 5c, 5d, and 5e are merely exemplary, and the present invention is not limited thereto.

[0085] FIG. 6a is a plan view illustrating a substrate used in a method for manufacturing a semiconductor package according to embodiments of the present invention. FIG. 6b and FIG. 6c are cross-sectional views illustrating the performance of a solder ball attach process in a method for manufacturing a semiconductor package according to embodiments of the present invention.

[0086] Referring to FIG. 6a, work areas of the substrate (100) can be determined by determining the method of the solder ball attach process (S300, see FIG. 1b). For example, the substrate (100) may include a first work area (R1), a second work area (R2), a third work area (R3), and a fourth work area (R4). The first work area (R1) and the second work area (R2) may be spaced apart from each other in a first direction (D1). The third work area (R3) may be located between the first work area (R1) and the second work area (R2). The fourth work area (R4) may be located between the first work area (R1) and the third work area (R3).

[0087] The width of the first work area (R1) in the first direction (D1) may differ from the width of the second work area (R2) in the first direction (D1). The width of the first work area (R1) in the first direction (D1) may be substantially the same as the width of the fourth work area (R4) in the first direction (D1) adjacent to the first work area (R1) in the first direction (D1). The width of the second work area (R2) in the first direction (D1) may be substantially the same as the width of the third work area (R3) in the first direction (D1) adjacent to the second work area (R2) in the first direction (D1).

[0088] Referring to FIG. 6b, a third solder ball attachment process can be performed on a third work area (R3) of the substrate (100). Adsorbing solder balls (B) into the adsorption holes (250h), a first solder ball attachment process for a first work area (R1), and a second solder ball attachment process for a second work area (R2) can be performed in the same manner as described with reference to FIG. 5a, 5b, and 5c.

[0089] The third solder ball attachment process can be performed by adsorbing the solder balls (B) into the adsorption holes (250h) again after the second solder ball attachment process, moving the ball tool (200) in the first direction (D1) so that the second tool area (TR2) of the ball tool (200) overlaps with the third work area (R3) of the substrate (100) in the third direction (D3), and driving the second drive unit (222) to move the pressing plate (230) and pins (240) of the second holder (H2) downward. Accordingly, the solder balls (B) can be attached to the pads (110) of the third work area (R3).

[0090] During the third solder ball attachment process, the third tool area (TR3) of the ball tool (200) and the second part (252) of the suction plate (250) may overlap with the second work area (R2) of the substrate (100) in the third direction (D3). At this time, due to the height difference (HD) between the lower surface of the first part (251) of the suction plate (250) and the lower surface of the second part (252), the solder balls (B) already attached to the second work area (R2) may be separated from the lower surface (200b) of the ball tool (200) in the third direction (D3) and may be free from the influence of the ball tool (200) approaching the substrate (100). During the third solder ball attachment process, the temperature of the third work area (R3) may differ from the temperatures of the first, second, and fourth work areas (R1, R2, R4).

[0091] Referring to FIG. 6c, a fourth solder ball attachment process can be performed on a fourth work area (R4) of a substrate (100). The fourth solder ball attachment process can be performed by moving the ball tool (200) in a first direction (D1) so that the first tool area (TR1) of the ball tool (200) overlaps with the fourth work area (R4) in a third direction (D3) after the third solder ball attachment process, and by driving the first drive unit (221) to move the pressing plate (230) and pins (240) of the first holder (H1) downward. Accordingly, solder balls (B) can be attached to the pads (110) of the fourth work area (R4).

[0092] During the fourth solder ball attachment process, the third tool area (TR3) of the ball tool (200) and the second part (252) of the suction plate (250) may overlap with the first work area (R1) of the substrate (100) in the third direction (D3). At this time, due to the height difference (HD) between the lower surface of the first part (251) of the suction plate (250) and the lower surface of the second part (252), the solder balls (B) already attached to the first work area (R1) may be separated from the lower surface (200b) of the ball tool (200) in the third direction (D3) and may be free from the influence of the ball tool (200) approaching the substrate (100). During the fourth solder ball attachment process, the temperature of the fourth work area (R4) may differ from the temperatures of the first, second, and third work areas (R1, R2, R3).

[0093] Referring to FIGS. 6b and FIGS. 6c in comparison with FIGS. 5d and FIGS. 5e, the area overlapping between the substrate (100) and the ball tool (200) in the third direction (D3) during the third and fourth solder ball attach processes can be reduced.

[0094] According to the method for manufacturing a semiconductor package of the present invention, the working areas of the substrate (100) are divided to anticipate the error of the solder ball attachment process, and a ball tool (200) is manufactured accordingly. By performing a plurality of solder ball attachment processes for each divided working area, the solder balls (B) can be accurately placed on the center of each of the pads (110) on the substrate (100) (i.e., the alignment error between the solder balls and the pads can be prevented and / or minimized), and accordingly, the reliability and electrical characteristics of the semiconductor package can be improved.

[0096] Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention may be implemented in other specific forms without changing its technical concept or essential features. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

Claim 1 A method for manufacturing a semiconductor package comprising: examining the structure and material of a substrate; estimating an error in the solder ball attachment process; determining the specifications of a ball tool and the method of the solder ball attachment process according to the estimated error; manufacturing the ball tool; and performing the solder ball attachment process, wherein the substrate comprises a plurality of work areas, and determining the specifications of the ball tool and the method of the solder ball attachment process comprises determining the number of holders of the ball tool, the position and width of the holders, and determining the number of work areas, the position and width of each of the work areas, and performing the solder ball attachment process comprises independently controlling the temperature of each of the work areas. Claim 2 A method for manufacturing a semiconductor package according to claim 1, wherein the working areas of the substrate include a first working area and a second working area having a width different from that of the first working area, and the ball tool includes a first holder of a first tool area having the same width as the first working area and a second holder of a second tool area having the same width as the second working area. Claim 3 A method for manufacturing a semiconductor package according to claim 2, wherein the ball tool further comprises a third tool region between the first tool region and the second tool region, and each of the first holder and the second holder comprises a suction plate having a pressing plate, pins below the pressing plate, and suction holes configured to allow the pins to move, and the suction plate comprises a first portion on the first tool region and a second portion extending from the first portion onto the third tool region, and the lower surface of the first portion of the suction plate is located at a different level from the lower surface of the second portion of the suction plate. Claim 4 A method for manufacturing a semiconductor package according to claim 3, wherein the height difference between the lower surface of the first part of the adsorption plate and the lower surface of the second part of the adsorption plate is 150 μm to 250 μm. Claim 5 A method for manufacturing a semiconductor package according to claim 2, wherein the working regions of the substrate further include a third working region between the first working region and the second working region, and a fourth working region between the third working region and the first working region, wherein the third working region has the same width as the first working region and the fourth working region has the same width as the second working region. Claim 6 A method for manufacturing a semiconductor package according to claim 5, wherein performing the solder ball attach process comprises: adsorbing solder balls onto each of the first holder and the second holder; moving the ball tool so that the first work area and the first holder overlap, thereby performing a first solder ball attach process on the first work area; moving the ball tool so that the second work area and the second holder overlap, thereby performing a second solder ball attach process on the second work area; adsorbing solder balls onto each of the first holder and the second holder again; moving the ball tool so that the third work area and the first holder overlap, thereby performing a third solder ball attach process on the third work area; and moving the ball tool so that the fourth work area and the second holder overlap, thereby performing a fourth solder ball attach process on the fourth work area. Claim 7 A method for manufacturing a semiconductor package according to claim 6, wherein during the first solder ball attach process, the temperature of the first work area is different from the temperatures of the second, third, and fourth work areas; during the second solder ball attach process, the temperature of the second work area is different from the temperatures of the first, third, and fourth work areas; during the third solder ball attach process, the temperature of the third work area is different from the temperatures of the first, second, and fourth work areas; and during the fourth solder ball attach process, the temperature of the fourth work area is different from the temperatures of the first, second, and third work areas. Claim 8 A method for manufacturing a semiconductor package according to claim 2, wherein the working regions of the substrate further include a third working region between the first working region and the second working region, and a fourth working region between the third working region and the first working region, wherein the third working region has the same width as the second working region and the fourth working region has the same width as the first working region. Claim 9 A method for manufacturing a semiconductor package according to claim 1, wherein the error in the solder ball attach process includes misalignment between the substrate and the ball tool due to the expansion / contraction of the substrate and the driving error of the ball tool. Claim 10 A method for manufacturing a semiconductor package according to claim 1, wherein the holders are provided in plurality, and the number of the holders is less than or equal to the number of the work areas.

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