WO2006001564A1

WO2006001564A1 - Semiconductor package picker

Info

Publication number: WO2006001564A1
Application number: PCT/KR2004/003340
Authority: WO
Inventors: Yong-Chae Jo
Original assignee: Hanmi Semiconductor Co., Ltd
Priority date: 2004-06-25
Filing date: 2004-12-17
Publication date: 2006-01-05
Also published as: KR20050122909A

Abstract

Disclosed is a semiconductor package picker. The semiconductor package picker does not seal a gap formed between a ball grid array (BGA) and a pad, but create strong negative pressure in the gap, thereby allowing the pad to pick up the semiconductor pad. The semiconductor package picker reliably picks up the BGA package even if the BGA is formed on an upper surface of the BGA package in addition to a bottom surface thereof.

Description

SEMICONDUCTOR PACKAGE PICKER

Technical Field The present invention relates to a semiconductor package picker. More particularly, the present invention relates to a semiconductor package picker capable of reliably picking up semiconductor packages with superior endurance.

Background Art In general, semiconductor packages are obtained by attaching semiconductor chips formed with highly integrated circuits, such as transistors and capacitors, to semiconductor substrates made from silicon and then molding resin onto upper surfaces of the semiconductor substrates. Among those semiconductor packages, a semiconductor package having a ball grid array (BGA), which is attached to a bottom surface of a semiconductor substrate such that it may serve as a lead frame electrically communicated with a semiconductor chip, is called a "BGA package". The BGA package is transferred to various process stages by means of a semiconductor package picker for the purpose of a sawing process, a vision inspection process, etc. Various semiconductor package pickers have been developed to transfer the BGA package. For example, FIGS. 1, 2a and 2b show a conventional semiconductor package picker using a rubber pad. As shown in FIG. 1, a conventional semiconductor package picker 10 includes a housing 11 having a hollow cylindrical structure and forming a body of the semiconductor package picker 10. The housing 11 is fixed to a picker assembly, which can be horizontally and longitudinally moved, by means of a picker support 19. A hollow housing shaft 12 having an air path is slidably installed in the housing 11 and a hollow pad holder 14 having an air path is coupled to a lower end of the housing 11. A pad holder spring 13 is positioned between the hollow pad holder 14 and the housing 11 so that the hollow pad holder 14 is downwardly biased by means of the pad holder spring 13. In addition, a rubber pad 17 provided at a lower portion thereof with a rim 18 is coupled to a lower portion of the hollow pad holder 14. An ejector pin 16 is provided in the hollow pad holder 14 in such a manner that the ejector pin 16 can protrude out of the rubber pad 17 through an air path of the rubber pad 17 while being downwardly biased by means of an ejector spring 15. Reference numeral 12a is a head part of the hollow housing shaft 12 for installing a pneumatic fitting (see, FIG. 5) while preventing the hollow housing shaft 12 from moving downwardly out of the housing 11. According to the conventional semiconductor package picker having the above construction, the ejector pin 16 first makes contact with a BGA package P when the semiconductor package picker moves down so that the ejector pin 16 moves up while compressing the ejector spring 15. Then, as the semiconductor package picker moves further, the rim 18 provided at the lower portion of the rubber pad 17 closely makes contact with an outer peripheral portion of the BGA package P, thereby moving up the housing shaft 12. Accordingly, the pad holder spring 13 is compressed and the rim 18 closely adheres to the outer peripheral portion of the BGA package P. Thus, a vacuum chamber is formed in the rim 18 due to a vacuum fed into the rim 18 through the air paths, so the BGA package P is picked up by means of the rubber pad 17. However, as the BGA package has recently been highly integrated, the BGA is provided at an upper peripheral portion of the BGA package (see, FIG. 4). If the BGA package is provided at the upper surface thereof with the BGA, a lower surface of the rubber pad of the conventional semiconductor package picker does not closely make contact with the upper surface of the BGA package, but form a gap between the rubber pad and the BGA package. Such a gap may cause leakage of the vacuum, so the conventional semiconductor package picker cannot effectively pick up the BGA package because suction force of the conventional semiconductor package picker becomes reduced. In order to solve the above problem, an expensive sponge pad having a superior shape-change characteristic is applied to the semiconductor package picker, instead of the rubber pad, in order to pick up the semiconductor package. FIGS. 3, 4a and 4b show the conventional semiconductor package picker equipped with the sponge pad. As shown in FIG. 3, when the semiconductor package picker picks up the BGA package, the sponge pad 17 coupled to a lower end of the hollow pad holder 14 moves down together with the housing 11 so that the sponge pad 17 closely makes contact with the upper surface of the BGA package P in order to pick up the BGA package by using a vacuum applied thereto through the vacuum line (see, FIGS. 4a and 4b). However, although the sponge pad can effectively pick up the BGA package at an early stage of use due to its superior shape-change characteristic, the dynamic stability of the sponge pad may become degraded and wear of the sponge pad may significantly increase with use as time goes by, so vacuum leakage may occur between the sponge pad 17 and the BGA B. Since such a vacuum leakage degrades suction force of the sponge pad 17 with regard to the BGA package, it is necessary to frequently replace the expensive sponge pad 17. In the meantime, FIG. 5 shows a structure of a conventional semiconductor package pickup system and FIG. 6 shows pneumatic and electric circuits for the conventional semiconductor package pickup system. Referring to FIGS. 5 and 6, a pressure sensor 40 is installed on the vacuum line of each semiconductor package picker 10 in order to detect whether the BGA package P is securely picked by the pad 17 based on pressure variation in the vacuum line. In addition, since each semiconductor package picker 10 picks up the BGA package by using a vacuum, a pneumatic pump 50, a solenoid valve 20 and a micro ejector 30 are provided as a vacuum source for the semiconductor package picker 10. Pressurized air generated from the pneumatic pump 50 is selectively introduced into the micro ejector 30 through the solenoid valve 20. That is, if the solenoid valve 20 is opened, the pressurized air is introduced into the micro ejector 30 through the solenoid valve 20. The pressurized air introduced into the micro ejector 30 is discharged from the micro ejector 30 by passing through a nozzle (not shown) and a discharge port 70 of the micro ejector 30. At this time, pressure between the nozzle and the discharge port 70 may drop so that air contained in the pad 17 of the semiconductor package picker 10 is introduced into a space formed between the nozzle and the discharge port 70 through the vacuum line connected to the space and then is discharged to an exterior together with the pressurized air through the discharge port 70 of the micro ejector 30. However, vacuum force generated by the micro ejector 30 is very weak so that the semiconductor package picker 10 cannot securely pick up the BGA package P if the vacuum leakage occurs between the picker pad 17 and the BGA package P. Meanwhile, the pressure sensor 40 detects whether the pad 17 securely picks up the BGA package P based on pressure variation in the vacuum line 80. However, the pressure sensor 40 cannot detect minute pressure variation in the vacuum line 80, so the pressure sensor 40 may erroneously determine that the BGA package P is not picked up by the semiconductor package picker 10 even though the semiconductor package picker 10 picks up the BGA package P. In addition, since the semiconductor package picker 10 operated in the above semiconductor package pickup system must be equipped with the expensive micro ejector 30 in addition to the solenoid valve 20, the manufacturing cost as well as the repair and maintenance cost for the semiconductor package picker 10 may increase.

Disclosure of the Invention Therefore, the present invention has been made in view of the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide a semiconductor package picker capable of reliably picking up semiconductor packages with superior endurance. Another object of the present invention is to provide a semiconductor package picker capable of reliably detecting whether a piker head securely picks up a semiconductor package. According to an aspect of the present invention, there is provided a semiconductor package picker, the semiconductor package picker comprising: a housing; a housing shaft movably inserted into the housing and formed with a hollow section extending lengthwise along the housing shaft; a pad holder coupled to a lower portion of the housing shaft and formed with an air path communicated with the hollow section of the housing shaft; a pad coupled to a lower end portion of the pad holder and formed with an air suction hole communicated with the air path of the pad holder; and an ejector pin elastically installed on the pad holder such that the ejector pin selectively protrudes beyond a lower end of the pad or returns to an initial position thereof, wherein external air is sequentially introduced into the air suction hole, the air path and the hollow section through a gap formed between a semiconductor package and the pad by means of strong vacuum force applied thereto from an exterior so that the pad securely picks up the semiconductor package. The pad has a planar-shaped package suction plane. It is preferred that the semiconductor package picker further comprises a means for detecting whether the semiconductor package is picked up by means of the pad based on up/down movements of the ejector pin. It is preferred that the detecting means includes a hollow sleeve fixed to a lower end of the housing shaft and inserted into the pad holder, the ejector pin includes an ejector pin head, a lower portion of the ejector pin head is elastically supported on the pad holder by means of a spring installed at an end portion of the housing shaft, a peripheral portion of the ejector pin head is surrounded by the sleeve, the housing, the housing shaft, the ejector pin spring, the ejector pin head and the pad holder are made from conductors, the sleeve and the ejector pin are made from nonconductors, the housing, the housing shaft, the ejector pin spring, the ejector pin head and the pad holder form an electric circuit in relation to a controller, the controller determines that the semiconductor package is picked up by the pad if the ejector pin moves up and the ejector pin head moves away from the pad holder, and the controller determines that the semiconductor package is not picked up by the pad if the ejector pin moves down and the ejector pin head makes contact with the pad holder. It is preferred that the strong vacuum force is generated from a vacuum source including a single vacuum generator, a plurality of vacuum lines branched from the vacuum generator and connected to the housing shaft, and a solenoid valve installed on each vacuum line in order to control the vacuum force generated from the vacuum generator.

Brief Description of the Drawings FIG. 1 is a longitudinal sectional view illustrating a conventional semiconductor package picker for picking up a BGA package equipped with a pad made from rubber; FIGS. 2a and 2b show a longitudinal sectional view and a partial enlarged view illustrating a semiconductor package picker shown in FIG. 1 when the semiconductor package picker picks up a BGA package; FIG. 3 is a longitudinal sectional view illustrating a conventional semiconductor package picker for picking up a BGA package equipped with a pad made from sponge; FIGS. 4a and 4b show a longitudinal sectional view and a partial enlarged view illustrating a semiconductor package picker shown in FIG. 3 when the semiconductor package picker picks up a BGA package; FIG. 5 is a schematic view illustrating a semiconductor package pickup system for operating a conventional semiconductor package picker for a BGA package; FIG. 6 is a schematic view illustrating pneumatic and electric circuits for a semiconductor package pickup system shown in FIG. 5; FIG. 7 is an exploded perspective view of a semiconductor package picker according to a first embodiment of the present invention; FIG. 8 is an assembled perspective view of a semiconductor package picker shown in FIG. 7; FIG. 9 is a longitudinal sectional view illustrating an internal structure of a semiconductor package picker shown in FIG. 7; FIGS. 10a and 10b are longitudinal sectional views illustrating operational states of a semiconductor package picker shown in FIG. 7; FIG. 11 is a longitudinal sectional view illustrating an internal structure of a semiconductor package picker according to a second embodiment of the present invention; FIG. 12 is a longitudinal sectional view illustrating an internal structure of a semiconductor package picker according to a third embodiment of the present invention; FIG. 13 is a longitudinal sectional view illustrating an internal structure of a semiconductor package picker according to a fourth embodiment of the present invention; FIG. 14 is a schematic view illustrating a semiconductor package pickup system for operating a semiconductor package picker according to one embodiment of the present invention; FIG. 15 is a schematic view illustrating pneumatic and electric circuits for a semiconductor package pickup system shown in FIG. 14; and FIG. 16 is a schematic view illustrating a semiconductor package pickup system for operating a semiconductor package picker according to another embodiment of the present invention.

Best Mode for Carrying Out the Invention Hereinafter, a first embodiment of the present invention will be described. FIG. 7 is an exploded perspective view of a semiconductor package picker according to the first embodiment of the present invention, FIG. 8 is an assembled perspective view of the semiconductor package picker shown in FIG. 7, and FIG. 9 is a longitudinal sectional view illustrating an internal structure of the semiconductor package picker shown in FIG. 7. Referring to FIGS. 7 to 9, the semiconductor package picker 100 according to the first embodiment of the present invention mainly includes a housing 110, a sleeve 120, a pad holder 130, a pad 140, an ejector pin 150 and a controller 160. The housing 110 has a hollow cylindrical structure and forms a body of the semiconductor package picker 100. An upper portion of the housing 110 is fixed to a picker support 170. A housing shaft 112 having a hollow section 114 formed lengthwise along the housing shaft 110 is installed in the housing 110 such that the housing shaft 112 can move up and down in the housing 110. A shaft slot 116 is formed at a lower peripheral portion of the housing shaft 112 and a spring recess 1 18 is formed at a lower end portion of the housing shaft 1 12. The sleeve 120 is coupled to a lower portion of the housing shaft 112. The sleeve 120 has a cylindrical shape and is divided into upper and lower parts. The lower part of the sleeve 120 has a diameter smaller than that of the upper part of the sleeve 120. A sleeve slot 122 is formed at a lower peripheral portion of the sleeve 120 corresponding to the shaft slot 116 of the housing shaft 112. The pad holder 130 is provided to hold the pad 140. A hollow section 131 is formed at an upper portion of the pad holder 130, thereby forming an air path. A lower portion of the sleeve 120 is inserted into the hollow section 131 of the pad holder 130 and then an upper portion of the sleeve 120 is fixedly press-fitted into the pad holder 130. Therefore, an air passage is formed between the hollow section 131 of the pad holder 130 and the lower part of the sleeve 120. In addition, an ejector pin passage hole 132 is formed in a lower portion of the pad holder 130 and an air path 134 communicated with the hollow section 131 is formed in the pad holder 130 while being spaced from the ejector pin passage hole 132 by a predetermined distance. A spring 138 is installed between the pad holder 130 and the housing 110 so that the pad holder 130 is downwardly biased from the housing 110. The spring 138 is aligned between a spring mount 124 installed at a lower end of the housing 110 and a spring support 120 formed at an outer peripheral portion of the pad holder 130. Reference numeral 113 is a head part of the hollow housing shaft 112 for installing a pneumatic fitting (see, FIGS. 14 and 16) while preventing the hollow housing shaft 112 from downwardly moving out of the housing 110. The pad 140 is coupled to a lower portion of the pad holder 130 in order to pick up the semiconductor package P by using a vacuum. The pad 140 is formed at a center portion thereof with an ejector pin insertion hole 142. In addition, an air suction hole 144 is formed in the pad 140 while being spaced from the ejector pin insertion hole 142 by a predetermined distance. Differently from the conventional pad, the pad 140 of the present invention has a planar-shaped package suction plane. Preferably, the pad 140 is fabricated by using rubber having superior endurance and elasticity sufficient for protecting the semiconductor package P. In addition, plastic or resin can also be used as materials for the pad 140 if they have superior endurance and do not cause damage to the semiconductor package when picking up the semiconductor package. According to the present invention, since the pad 140 has the planar-shaped package suction plane, it is not necessary to closely adhere the pad 140 to the semiconductor package when picking up the semiconductor package. That is, according to the present invention, strong vacuum force is applied to the semiconductor package through the pad 140 while the pad 140 is being spaced from the semiconductor package, thereby picking up the semiconductor package. Thus, the conventional pressure sensor cannot be used for the semiconductor package picker of the present invention. According to the present invention, instead of the pressure sensor, a mechanical mechanism is provided in the semiconductor package picker to detect whether the semiconductor package is picked up by means of the semiconductor package picker. Thus, it is possible to reliably detect whether the semiconductor package picker picks up the semiconductor package. The ejector pin 150 is used for ejecting the semiconductor package in such a manner that the semiconductor package can be prevented from adhering to the pad 140 when the semiconductor package is released from the semiconductor package picker. The ejector pin 140 moves up and down through the ejector pin passage hole 132 and the ejector pin insertion hole 142 in such a manner that it may protrude out of the pad 140 or return into the pad 140. An ejector pin head 152 is fixedly installed on an upper portion of the ejector pin 150. The ejector pin head 152 elastically makes contact with the pad holder 130 or moves away from the pad holder 130 by means of an ejector pin spring 154. The controller 160 controls the operation of the semiconductor package picker based on the pickup state of the semiconductor package P. As described above, according to the present invention, the pickup state of the semiconductor package is detected according to the up/down movement of the ejector pin 150 having a function of ejecting the semiconductor package, instead of using the pressure sensor. In detail, the sleeve 120 and the ejector pin 150 are made from nonconductors, and the housing shaft 1 12, the ejector pin spring 154, the ejector pin head 152 and the pad holder 130 are made from conductors in such a manner that they may form an electric circuit in relation to the controller 160. Thus, as the ejector pin 150 moves up or down depending on the pickup state of the semiconductor package, the ejector pin head 152 makes contact with the pad holder 130 or moves away from the pad holder 130, thereby switching on or off the electric circuit. That is, if the semiconductor package is picked up by the pad 140, the ejector pin 150 moves up, so the ejector pin head 152 moves away from the pad holder 130, thereby switching off the electric circuit. In this case, the controller 160 determines that the semiconductor package is picked up by means of the pad 140, so the controller 160 controls the next operation of the semiconductor package picker. In contrast, if the semiconductor package is not picked up by means of the pad 140, the ejector pin 150 moves down so that the ejector pin head 152 makes contact with the pad holder 130, thereby switching on the electric circuit. In this case, the controller 160 determines that the semiconductor package is not picked up by means of the pad 140. Accordingly, the controller 160 sends an error signal to the semiconductor package picker in order to stop the operation of the semiconductor package picker or to allow a worker to take necessary steps. Hereinafter, the operation of the semiconductor package picker according to the first embodiment of the present invention will be described. FIG. 1 Oa shows the semiconductor package picker before it picks up the semiconductor package and FIG. 10b shows the semiconductor package picker after it has picked up the semiconductor package. Referring to FIG. 10a, before the semiconductor picker picks up the semiconductor package, external air is introduced into the semiconductor package picker through the air suction hole 144 and is discharged to the exterior through the air path 134, the sleeve slot 122, the shaft slot 116 and the hollow section 114. At this time, the ejector pin 150 maintains in the down position so that the lower portion of the ejector pin 150 downwardly protrudes beyond a lower end of the pad 140 and the ejector pin head 152 makes contact with the pad holder 130 so that the electric circuit is switched on. Accordingly, the controller 160 determines that the semiconductor package is not picked up by means of the pad 140. Referring to FIG. 10b, after the semiconductor picker has picked up the semiconductor package, external air is introduced into the semiconductor package picker through the air suction hole 144 along a gap formed between the lower surface of the pad 140 and the BGA of the semiconductor package and is discharged to the exterior through the air path 134, the sleeve slot 122, the shaft slot 116 and the hollow section 114 of the housing shaft 112. At this time, the ejector pin 150 maintains in the up position so that the ejector pin head 152 moves away from the pad holder 130, thereby switching off the electric circuit. Accordingly, the controller 160 determines that the semiconductor package is picked up by means of the pad 140, so the controller 160 controls the next operation of the semiconductor package picker. Hereinafter, the second embodiment of the present invention will be described. FIG. 11 illustrates an internal structure of a semiconductor package picker according to the second embodiment of the present invention. Referring to FIG. 11, the semiconductor package according to the second embodiment of the present invention is substantially identical to the semiconductor package according to the first embodiment of the present invention except for the housing shaft 112, the sleeve 120 and the pad holder 130, so the same parts thereof will not be further described below. Thus, the following description will be made in relation to the housing shaft 112, the sleeve 120 and the pad holder 130 according to the second embodiment of the present invention while focusing on different parts thereof with respect to those of the first embodiment of the present invention. Differently from the housing shaft according to the first embodiment of the present invention, the housing shaft 112 according to the second embodiment of the present invention does not have the shaft slot 116 at a lower peripheral portion thereof, but the spring recess 1 18 formed at the lower end portion of the housing shaft 112 has the shaft slot 116. hi addition, the spring recess 118 is provided with a protrusion 119 for supporting the ejector pin spring 154. The sleeve 120 has a hollow cylindrical structure. However, the sleeve 120 according to the second embodiment of the present invention is integrally formed without being divided into upper and lower parts and closely adheres to the pad holder 130. hi addition, the sleeve 120 has no sleeve slot 122 at the lower peripheral portion thereof. In the meantime, the pad holder 130 according to the second embodiment of the present invention does not have the air path 134. In addition, the ejector pin passage hole 132 formed in the pad holder 130 has a diameter larger than that of the ejector pin 150, so that a gap formed between the ejector pin 150 and the ejector pin passage hole 132 serves as an air path identical to the air path 134 according to the first embodiment of the present invention. As described above, although the semiconductor package picker according to the second embodiment of the present invention has performance identical to that of the semiconductor package picker according to the first embodiment of the present invention, the semiconductor package picker according to the second embodiment of the present invention does not require the shaft slot 116 formed at the peripheral portion of the housing shaft 1 12 and the sleeve slot 122 formed at the peripheral portion of the sleeve 120. hi addition, according to the second embodiment of the present invention, it is not necessary to additionally form the air path in the pad holder 130, so the structure and the shape of the semiconductor package picker according to the second embodiment of the present invention can be simplified. Hereinafter, the third embodiment of the present invention will be described. FIG. 12 illustrates an internal structure of a semiconductor package picker according to the third embodiment of the present invention. Referring to FIG. 12, the semiconductor package according to the third embodiment of the present invention is substantially identical to the semiconductor package according to the first embodiment of the present invention except for the pad 140. Differently from the pad according to the first embodiment of the present invention, the pad 140 according to the third embodiment of the present invention does not have the ejector pin insertion hole 142, but the air suction hole 144 is largely formed at the lower portion of the pad 140. Hereinafter, the fourth embodiment of the present invention will be described. FIG. 13 illustrates an internal structure of a semiconductor package picker according to the fourth embodiment of the present invention. Referring to FIG. 13, the semiconductor package according to the fourth embodiment of the present invention is substantially identical to the semiconductor package according to the first embodiment of the present invention except for the ejector pin head 152 installed on the upper portion of the ejector pin 150. According to the fourth embodiment of the present invention, the ejector pin head 152 is provided at a lower surface thereof with a protrusion 153. The protrusion 153 allows the ejector pin head 152 to easily make contact with the pad holder 130 even if dust or impurities are formed between the ejector pin head 152 and the pad holder 130. Although the protrusion 153 having a sharpness tip is illustrated, the tip of the protrusion 153 can be formed with various shapes if it does not exert a bad influence upon the switching operation. Hereinafter, description will be made in relation to the semiconductor package pickup system for attaining the above-mentioned embodiments according to the present invention. FIG. 14 is a schematic view illustrating the semiconductor package pickup system for operating the semiconductor package picker according to one embodiment of the present invention and FIG. 15 is a schematic view illustrating pneumatic and electric circuits for the semiconductor package pickup system shown in FIG. 14. Referring to FIGS. 14 and 15, semiconductor package pickers 100 are connected to a plurality of vacuum lines 300 branched from a single vacuum pump 400 for generating vacuum force, respectively. In addition, each vacuum line 300 is equipped with a solenoid valve 200. The solenoid valve 200 controls the vacuum force generated from the vacuum pump 400 in order to individually control the semiconductor package pickers 100. That is, according to the present invention, it is not necessary to provide the pneumatic pump and the micro ejector, which serve as the vacuum source for the conventional semiconductor package picker. The vacuum pump 400 preferably includes a PIAB pump (PIAB; Model Name) capable of generating strong negative pressure, instead of the pneumatic pump. Since the PIAB pump can generate strong vacuum force, the pad 140 can stably pick up the semiconductor package even if the vacuum leakage occurs in the semiconductor package picker. Besides the PIAB pump, various pumps can be used for the present invention if they can generate negative pressure sufficient for picking up the semiconductor package P while constantly maintaining a gap formed between the semiconductor package P and the pad 140. Referring to FIG. 15, the present invention does not use the pressure sensor for detecting the pickup state of the semiconductor package. That is, according to the present invention, the housing 110, the housing shaft 112, the ejector pin spring 154, the ejector pin head 152 and the pad holder 130 are made from conductors in such a manner that they may form the electric circuit in relation to the controller 160. In this case, the ejector pin head 152 makes contact with the pad holder 130 or moves away from the pad holder 130 as the ejector pin 150 moves down or up, thereby switching on or off the electric circuit. Accordingly, it is possible to reliably detect the pickup state of the semiconductor package even if the leakage or pressure variation occurs in the semiconductor package picker. FIG. 16 is a schematic view illustrating a semiconductor package pickup system for operating a semiconductor package picker according to another embodiment of the present invention. According to another embodiment of the present invention, a single solenoid valve 200 is installed before vacuum lines 300 are branched from the vacuum pump 400 to transfer the vacuum force of the vacuum pump 400, thereby centrally controlling the operation of the semiconductor package pickers. While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment and the drawings, but, on the contrary, it is intended to cover various modifications and variations within the spirit and scope of the appended claims. For instance, although the present invention has been described in relation to the BGA package, the present invention is not limited thereto, but is applicable for various types of semiconductor packages.

Industrial Applicability As can be seen from the foregoing, the present invention provides the semiconductor package picker capable of reliably picking up the BGA package even if the BGA is formed on the upper surface of the BGA package in addition to the bottom surface of the BGA package. In addition, since the present invention can use the rubber pad capable of reliably picking up the semiconductor package with superior wear-proof characteristics, so the exchange period of the pad can be economically lengthened. Furthermore, the semiconductor package picker according to the present invention can reliably detect the pickup state of the semiconductor package by using a mechanical mechanism (up/down movement) of the ejector pin, so it is not necessary to use the conventional pressure sensor. In addition, the present invention does not use expensive micro ejectors installed on vacuum lines, thereby reducing manufacturing cost as well as repair and maintenance cost for the semiconductor package picker.

Claims

Claims 1. A semiconductor package picker comprising: a housing; a housing shaft movably inserted into the housing and formed with a hollow section extending lengthwise along the housing shaft; a pad holder coupled to a lower portion of the housing shaft and formed with an air path communicated with the hollow section of the housing shaft; a pad coupled to a lower end portion of the pad holder and formed with an air suction hole communicated with the air path of the pad holder; and an ejector pin elastically installed on the pad holder such that the ejector pin selectively protrudes beyond a lower end of the pad or returns to an initial position thereof, wherein external air is sequentially introduced into the air suction hole, the air path and the hollow section through a gap formed between a semiconductor package and the pad by means of strong vacuum force applied thereto from an exterior so that the pad securely picks up the semiconductor package.

2. The semiconductor package picker as claimed in claim 1, wherein the pad has a planar-shaped package suction plane.

3. The semiconductor package picker as claimed in claim 1 or 2, further comprising a means for detecting whether the semiconductor package is picked up by means of the pad based on up/down movements of the ejector pin.

4. The semiconductor package picker as claimed in claim 3, wherein the detecting means includes a hollow sleeve fixed to a lower end of the housing shaft and inserted into the pad holder, the ejector pin includes an ejector pin head, a lower portion of the ejector pin head is elastically supported on the pad holder by means of a spring installed at an end portion of the housing shaft, a peripheral portion of the ejector pin head is surrounded by the sleeve, the housing, the housing shaft, the ejector pin spring, the ejector pin head and the pad holder are made from conductors, the sleeve and the ejector pin are made from nonconductors, the housing, the housing shaft, the ejector pin spring, the ejector pin head and the pad holder form an electric circuit in relation to a controller, the controller determines that the semiconductor package is picked up by the pad if the ejector pin moves up and the ejector pin head moves away from the pad holder, and the controller determines that the semiconductor package is not picked up by the pad if the ejector pin moves down and the ejector pin head makes contact with the pad holder.

5. The semiconductor package picker as claimed in claim 4, wherein the strong vacuum force is generated from a vacuum source including a single vacuum generator, a plurality of vacuum lines branched from the vacuum generator and connected to the housing shaft, and a solenoid valve installed on each vacuum line in order to control the vacuum force generated from the vacuum generator.