METHOD AND APPARATUS FOR INSPECTING AND PACKING CHIPS
BACKGROUND OF THE INVENTION
Field of the Invention
The present invent ion relates to a method and apparatus for inspecting and packaging chips which are packaged by inserting chips in corresponding chip receiving recesses formed on a surface of a roll film and closing openings of the chip receiving recesses by applying a tape thereon, and more particularly to a method and apparatus for inspecting and packaging chips, in which inspection and packaging works are simultaneously performed in a single process step so as to reduce the number of process steps .
Description of the Related Art
Generally, chips to be mounted on a printed circuit board (PCB) are packaged in a roll film shown in Fig. 3 before being shipped. The chips are packaged in such a manner that a roll film F having a plurality of chip receiving recesses 110 which are arranged at regular intervals along the longitudinal direction of the roll film F on a surface thereof is prepared, chips C are inserted into the respective chip receiving recesses 110 on the film
F, openings of the chip receiving recesses are closed by applying a tape 41 thereon, and the packaged chips are shipped in the form of a roll film. Unexplained reference numeral 120 denotes winding holes that help stepwise movements of the film F during package process steps .
During such a packaging work, only normal chips that passed a test for inspecting heights and deflections of leads of the chips are inserted into the chip receiving recesses 110 of the film F. That is, the chips are pre- inspected and abnormal chips are sorted out as a result of the inspection before the package work. Accordingly, an additional pre-inspection process is necessary in a conventional chip packaging method.
Fig. 4 illustrates a flow chart showing a method for packaging chips in accordance with a conventional art. A method for packaging chips comprises a first step for inspecting chips, a second step for selectively stacking normal chips and abnormal chips in different trays, a third step for mounting the normal chips onto chip receiving recesses on a film, and a fourth step for applying a tape to openings of the chip receiving recesses on the film.
The chips are inspected by an apparatus comprising a tray having a plurality of recesses thereon, which are arranged in a matrix to receive unsorted chips therein, and a probe for scanning the unsorted chips received in the tray
to inspect the chips while the probe moves along a row of the tray.
Accordingly, in the chip packaging method in accordance with the conventional art, an inspection process for sorting chips into normal or abnormal chips is separately performed from the chip packaging work, so that the number of process steps increases, the chip packaging work is complicated, and productivity is lowered due to low process efficiency.
SUMMARY OF THE INVENTION
Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a method and apparatus for simultaneously inspecting and packaging chips without a pre-inspection of chips so that the number of process steps is reduced, whereby a packaging work becomes simpler, efficiency of the packaging work is improved and productivity of the chips is improved. In accordance with one aspect of the present invention, the above and other objects can be accomplished by the provision of a method for inspecting and packaging chips, comprising a first step for advancing a film having a plurality of chip receiving recesses thereon from a film supplying roll to a film recovery roll by a stepwise
movement, inserting an uninspected chip into the chip receiving recess of the film, inspecting the chip passing under a three dimensional measuring probe by the three dimensional measuring probe, and replacing the inspected chip with a new chip by a robot arm when the probe determines that the inspected chip is abnormal, and a second step for attaching a tape onto the film to close an opening of the chip receiving recess having a normal chip therein after the first step is performed. In accordance with another aspect of the present invention, the above and other objects can be accomplished by the provision of an apparatus for inspecting and packaging chips, comprising a film transporting unit for advancing a film F having a plurality of chip receiving recesses thereon from a film supplying roll placed at a first spot to a film -recovery roll placed at a second spot distanced from the first spot by a stepwise movement, a probe installed above the film transporting . from the film supplying roll to the film recovery roll for measuring a three dimensional feature of a chip mounted in the chip receiving recess of the film and determining whether the chip is normal or abnormal, a robot arm for performing a sorting work by replacing an abnormal chip in the chip receiving recess of the film with a new normal chip, when the probe determines that the chip in the chip receiving recess of the film is abnormal, and a
taping unit for closing openings of the chip receiving recesses of the film, in which normal chips sorted by the robot arm are received.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
Fig. 1 illustrates a flow chart showing a method of inspecting and packaging chips to be mounted on a PCB, in accordance with the present invention;
Fig. 2 illustrates a schematic view of an apparatus for inspecting and packaging chips in accordance with the present invention; -
Fig. 3 illustrates a perspective view of a film for use in chip packaging; and
Fig. 4 illustrates a flow chart showing a method for packaging chips to be mounted on a PCB in accordance with the conventional art .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A detailed description of a method for inspecting and
packaging chips in accordance with a preferred embodiment of the present invention will be given below with reference to the accompanying drawings .
Fig. 1 illustrates a flow chart showing a method for inspecting and packaging chips in accordance with a preferred embodiment of the present invention.
Fig. 3 illustrates a film F for use in chip packaging. For packaging chips, chips C are placed in chip • receiving recesses 110 on a film F and respective openings of the chip receiving recesses 110 are closed by applying a tape 41 thereon. The film F is a roll film and has a plurality of winding holes at both side edge portions thereof, the winding holes being arranged at regular intervals along a longitudinal direction of the film F and helping step movements of the film F.
A method for inspecting and packaging chips in accordance with the present invention comprises a first step for simultaneously performing inspection of chips and sorting out abnormal chips as the chips are mounted in chip receiving recesses on a film, and a second step for closing openings of the chip receiving recesses by applying a tape on the film F.
In the conventional packaging method, a pre-inspection step is performed before a chip package work, but in the method of the present invention, the chips are inspected and sorted during the chip package work. Accordingly, the pre-
inspection step is not necessary in the packaging method in accordance with the preferred embodiment of the present invention.
That is, the inspection and sorting steps are simultaneously performed in the first step of the packaging method in accordance with the present invention. The first step is performed in such a manner that a film having a plurality of chip receiving recesses on a surface thereof moves step by step from a film supplying roll to a film recovery roll, unsorted chips are inserted into the chip receiving recesses of the film unrolled from the film supplying roll and moving to the film recovery roll in turn, the unsorted chips mounted into the chip receiving recesses of the unrolled part of the film are inspected -by a three dimensional measuring (TDM) probe installed above the unrolled
" part of the film while the unsorted chips move together with the film from the film supplying roll to the film recovery roll . In the case that the probe indicates that an inspected chip is abnormal, the inspected chip is replaced with a new normal chip. Therefore, inspection and sorting works are performed in the same step.
Preferably, the probe is a three dimensional measuring system disclosed in a Korean patent laid open publication no. 2002-78214 titled "Real Time Three Dimensional Measuring Method And Device Using Color Information" or in a Korean
patent laid open publication no. 2002-39583 titled "Method Of Measuring Phase Shift Projection-Type Moire Applying Moire Pattern Generator And Device Thereof", both of which are applied by the present applicant. The second step is a step for sealing the chip receiving recesses having normal chips therein by a tape. A size, or a width of the tape is preferably larger than that of an opening of the chip receiving recess to completely cover the opening of the chip receiving recess but is smaller than a length between the winding holes formed at both side edges of the film so that the winding holes are still exposed after the tape is applied on the film. The tape is attached on the surface of the film along the longitudinal direction of the film. As the tape is applied on the film, the film is rolled, and the chips are shipped as packaged in the roll film.
An apparatus for inspecting and packaging chips in accordance with the present invention will be described below, with reference to Fig. 2.
Referring to Fig. 2, an apparatus for inspecting and packaging chips comprises a film transporting unit 1 comprising a film supplying roll 11 placed at a first spot, a film recover roll 12 placed at a second spot separated from the first spot by a certain distance, and a motor or an intermittent transmission gear (not shown) for intermittently rotating the film recovery roll 12. As the film recover roll
12 intermittently rotates by the motor or the intermittent transmission gear (not shown) connected the film recovery roll 12, the film F is unrolled from the film supplying roll 11, and the unrolled part of the film is stepwisely moved toward the film recover roll 12 by a certain distance. The film has a plurality of chip receiving recesses 110 with respective openings. The chip receiving recesses 110 are formed at regular intervals along the longitudinal direction of the film F. The apparatus for inspecting and packaging chips in accordance with the present invention further comprises a three dimensional measuring probe 2 which is installed above the unrolled part of the film F moving from the first spot to the second spot. The three dimensional measuring probe 2 takes a three dimensional picture of a chip passing the probe 2 thereunder, so that a three dimensional geometric feature of the chip is displayed on a monitor 20 of a computer connected to the probe 2. As a result, the chips are sorted into normal or abnormal chips by naked eyes on the monitor 20. The apparatus for inspecting and packaging chips in accordance with the present invention further comprises an automatic chip replacing and sorting device such as a robot arm 3 which removes a chip classified into an abnormal chip and replaces the abnormal chip with a new normal chip while the film F advances to the film recovery roll step by step by
a predetermined distance. The operation of the robot arm 2 is controlled by a control signal generated in response to the failed chip detection by a controller.
The apparatus for inspecting and packaging chips in accordance with the present invention further comprises a taping unit 4 for closing openings of the chip receiving recesses 110 of the film F, in which normal chips C are received. The taping unit 4 comprises a tape 41, a taping roll 42 around which a tape 41 is wound, and a pressing roller 43 that advances and guides the tape 41 onto the film F and attaches the tape 41 onto the film F by pressing the tape 4.
The operation of the apparatus for inspecting and packaging chips in accordance with present invention will be described below. First, the film F is stepwisely moved from the film supplying roll 11 to the film recovery roll 12 by a certain distance as the film recovery roll 12 is rotated by the driving motor or the intermittent transmission gear, and no inspected chips C are mounted in the chip receiving recesses 110 of the film F moving from the film supplying roll 11 to the film recovery roll 12. When the chip C mounted on the film F passes a spot above which the probe 2 is installed, the chip is inspected by the probe 2 , and the inspection result is displayed on the monitor 20 connected to the probe. At this time, if the monitor indicates that the inspected chip is
abnormal, the robot arm 1 removes the abnormal chip from the chip receiving recess 110 of the film F and inserts a new normal chip into the chip receiving recess 110 of the film F in response to the control signal generated by the controller. For replacing and sorting out the abnormal chips, an abnormal chip loading unit and a normal chip loading unit (not shown) may be additionally provided.
While the film F on which the normal chip is mounted passes the pressing roller 43, the opening of the chip receiving recess 110 having the normal chip therein is sealed.
That is, when the film F having the normal chip C thereon reaches to the pressing roller 43, the tape drawn from the taping roll 42 is guided onto the film F to be overlapped with the film F by the pressing roller 43 and then the tape 41 is pressed against the film F by the pressing roller 43, so that the opening of the chip receiving recess 110 is closed by the tape 41.
As described above, in accordance with the present invention, inspection and sorting of chips are simultaneously performed in a single' step while the chips are transported from the film supplying roll to the film recovery roll as unspected chips are received in the respective chip receiving recesses of the film moving from the film supplying roll to the film recovery roll, so that the number of process steps for packaging the chips is reduced, and further the chip
packaging work becomes simpler, efficiency of the chip packaging work is improved and productivity of the chips is improved.
Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims .