KR100238269B1 - Coplanarity measurment apparatus for IC package lead fin - Google Patents

Abstract

A lead pin inspection method and apparatus of a flat package type IC are disclosed. A lead pin inspection method and apparatus of a flat packaged IC disclosed in the present invention emits light in a state in which a plurality of light emitting sensors and a light receiving sensor are positioned in a mutually parallel state with lead pins arranged in one side of the IC package interposed therebetween , The lead pin is shielded from light, and the amount of light received by the light receiving sensor is measured to detect the alignment state of the lead pin. With this configuration, the position error of the IC package adsorbed on the suction nozzle is corrected, So that the accuracy and efficiency of the device can be improved.

Description

Technical Field [0001] The present invention relates to a method of inspecting a lead pin of an IC package,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a lead-pin inspecting method and apparatus for an IC package, and more particularly, to an IC lead-pin inspecting method and apparatus for inspecting a deformation state such as a lead-

In general, a flat package type IC such as a QFP (Quad Flat Package) is mounted with a plurality of lead pins supported by the substrate. 1 is a schematic perspective view showing a QFP type IC package as an example of a flat packaged IC. The flat packaged IC 10 includes a main body 11 and a plurality of lead pins 12 arranged around the main body 11. [ The lead pin 12 includes a protruding portion 121 protruding laterally from the package body 11 as shown in the figure, an inclined portion 122 extending downward from the protruding portion 121 at a predetermined angle, And a pin portion 123 projecting from the portion 122 in the lateral direction.

The lead pin 12 having the above-described structure can be brought into a precise connection state with the substrate only when the IC package is surface-mounted on the substrate and the alignment conditions such as the position, direction, spacing, and height of the IC package are satisfied. However, if the above-mentioned conditions are not satisfied, the lead pin 12 may be lifted from the substrate 1 as shown in FIG. 2 when mounted on the substrate, so that proper soldering can not be performed. . Therefore, before the IC package is mounted on the surface of the substrate, the IC package is subjected to a process of checking an alignment state such as a prescribed position of the lead pin, an orientation, a gap, and a coplanarity due to a difference in height. As an example of a conventional inspecting method for performing the inspecting process, a light emitting sensor and a light receiving sensor are disposed at both ends of a lead pin protruding from one side of a body of the IC package, light is emitted from the light emitting sensor, There is a method of checking the lifting state (flatness) of the lead pin by measuring the amount of light reaching the sensor. An apparatus for carrying out such a conventional inspection method is schematically shown in Figs. 3 and 4. Fig.

3 and 4, the conventional lead pin inspecting apparatus includes a suction nozzle 111 for suctioning the IC package 10, a suction nozzle 111 for sucking the suction nozzle 111, A light emitting sensor 120 and a light receiving sensor 130 arranged in parallel so as to correspond to both ends in the direction of arrangement of the lead pins 12 protruding out of the body 11 of the IC package 10, The controller 140 can detect the alignment state of the lead pin 12 by measuring the amount of light received by the lead pin 12 and reaching the light receiving sensor 130 .

3 and 4, reference numeral 110 denotes a head unit which supports the suction nozzle 111 so that the suction nozzle 111 can move up and down. When the state inspection of the lead pin at one side of the IC package 10 is completed , And the head unit 110 moves or rotates the suction nozzle 111 to inspect the state of the other side of the lead pin. On the other hand, the head unit 110 is provided so as to be freely movable on a rectangular coordinate system, for example, by an XY robot or a multi-joint robot. Reference numerals 121 and 131 denote supporting members for supporting the light emitting sensor 120 and the light receiving sensor 130, respectively.

In the conventional lead pin inspecting apparatus having the above configuration, when the IC package 10 to be inspected is positioned at a predetermined position by a usual component supplying device or the like, the head part 110 is moved Next, the suction nozzle 11 descends to suck the IC package 10 to be inspected. The IC package 10 thus attracted is positioned in the inspection region between the light emitting sensor 120 and the light receiving sensor 130 by the movement of the head portion 110. In this state, light is emitted from the light emitting sensor 120 to the light receiving sensor 130. At this time, the larger the deviation of the lead pin 12, that is, the height difference, becomes, the smaller the amount of light received by the light receiving sensor 130 becomes. Therefore, by measuring the degree of the amount of light at which a part of the light emitted from the light emitting sensor 120 is shielded by the lead pin 12 of the IC package 10 and the remaining light reaches the light receiving sensor 130 (Flatness) of the lead pin 12 of the IC package 10 to be inspected can be detected.

However, since the conventional IC package lead pin inspecting apparatus as described above has a prerequisite condition that accurate inspection results can be obtained only when the body of the IC package to be inspected and the arrangement line of the lead pins are parallel to each other, There is a problem that the accuracy of the inspection result is deteriorated in the inspection process. Further, since accurate inspection results can be obtained only when accurate positioning is performed when the IC package to be inspected is sucked to the suction nozzle, accurate positioning results can be obtained. For example, in an actual inspection process, So that the inspection accuracy and efficiency are deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the lead pin inspection method and apparatus of the conventional IC package as described above, and it is an object of the present invention to provide a lead pin inspecting method, And to provide a lead-pin inspecting apparatus of an IC package having improved inspection efficiency.

It is another object of the present invention to provide a method of inspecting a lead pin of an IC package that improves the accuracy and efficiency of inspecting a lead pin of an IC package.

1 is a schematic perspective view showing a flat package type IC,

2 is a schematic cross-sectional view for explaining a substrate packaging state of a flat packaged IC,

3 is a perspective view schematically showing a configuration of an apparatus for inspecting a conventional IC package lead pin,

Fig. 4 is a schematic side view of Fig. 3 viewed from the "A &

5 is a schematic plan configuration diagram of an IC package lead pin inspecting apparatus according to the present invention,

6 is a schematic view for explaining an IC package lead pin inspecting method according to the present invention using the lead pin inspecting apparatus shown in FIG. 5, and FIG.

7 is a graph showing a state in which flatness of a lead pin is detected by the amount of received light received by a plurality of light receiving sensors in the IC package lead pin inspecting method and apparatus according to the present invention.

Description of the Related Art

10 .. IC Package 12 .. Lead Pins

210 .. Head part 211 .. Adsorption nozzle

220, 230. Supports 221, 222, 223.

231, 232, 233 .. Light receiving sensor 240 .. Controller

In order to attain the above object, the present invention provides an apparatus for inspecting a lead pin of an IC package, comprising: a nozzle for picking up a part; and a lead pin arranged on one side of the IC package, A plurality of light emitting sensors and light receiving sensors provided corresponding to each other in parallel with each other, and a light amount detecting unit for measuring an amount of light reaching the light receiving sensor by shielding light emitted from the light emitting sensor by the lead pins, And a controller for controlling the operation of the controller.

According to another aspect of the present invention, there is provided a method of inspecting a lead pin of an IC package, comprising the steps of: preparing a plurality of light emitting sensors and a light receiving sensor, The light emitted from the light emitting sensor is shielded by the lead pin and the amount of light reaching the light receiving sensor is measured to determine the alignment of the lead pins And detecting a state of the battery.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method and an apparatus for inspecting IC package lead pins according to preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 5 is a schematic plan view of an IC package lead pin inspecting apparatus according to the present invention, and FIG. 6 illustrates a method of inspecting an IC package lead pin according to the present invention using the IC package lead pin inspecting apparatus shown in FIG. Fig.

5, the apparatus for inspecting a lead pin according to the present invention includes a suction nozzle 211 for suctioning an IC package 10, an IC package (not shown) 222, 223 arranged so as to be parallel to each other at both ends in the arrangement direction with a lead pin 12 protruding out of the body 11 of the body 10 interposed therebetween, And three light receiving sensors 231, 232 and 233 and light emitted from each of the light emitting sensors 221, 222 and 223 are respectively shielded by the lead pins 12, 231) 232, 233, and detects a state of alignment of the lead pins 12. The controller 240 is configured to detect an alignment state of the lead pins 12 by measuring an amount of light received at the lead pins 231,

221 of the three light emitting sensors 221, 222 and 223 are arranged such that the light emitted therefrom forms an optical axis parallel to the one side L-L 'of the body 11 of the IC package 10 . Reference numerals 222 and 223 are respectively installed on both sides of the slant 221 in a tilted state so that the axis of the light emitted therefrom can form a predetermined angle (??) with the axis of the light emitted from the slant 221. Therefore, the axis of the light emitted from each of the light emitting sensors 221, 222 and 223 is approximately at a point F at the center of one side L-L 'of the body 11 of the IC package 10 Intersect. The three light receiving sensors 231, 232 and 233 are provided so as to correspond to the mounting structure of the light emitting sensors 221, 222 and 223, respectively, so that light not shielded by the lead pins 12 So that it can receive light.

5, a reference numeral 210 denotes a head for supporting the suction nozzle 211 so as to be able to move up and down. When the inspection of the lead pin 12 at one side of the IC package 10 is completed, And the head unit 210 has a function of moving or rotating the suction nozzle 211 so that the state of the other side of the lead pin can be inspected. On the other hand, the head unit 210 is provided so as to be freely movable on a rectangular coordinate system, for example, by an XY robot or a multi-joint robot. Reference numerals 220 and 230 denote supporting members for supporting the light emitting sensors 221, 222 and 223 and the light receiving sensors 231, 232 and 233, respectively.

The IC package lead pin inspecting apparatus according to the present invention having the above-described structure is configured such that when the IC package 10 to be inspected is aligned at a predetermined position by a usual component supplying device or the like, The suction nozzle 211 is lowered to suck the IC package 10 to be inspected. The absorbed IC package 10 is positioned in the inspection area between the light emitting sensors 221, 222, 223 and the light receiving sensors 231, 232, 233 by movement of the head part 210 . In this state, light is emitted from the light emission sensors 221, 222, and 223 to the light reception sensors 231, 232, and 233. At this time, as the lift-up state of the lead pin 12 of the IC package 10, that is, the height difference deviation, becomes larger, the amount of light shielded becomes larger, so that the amount of light reaching the light receiving sensor 231 (232) Therefore, the light emitted from the light emitting sensors 221, 222 and 223 is shielded by the lead pins 12 of the IC package 10 and reaches the light receiving sensors 231, 232 and 233 The flatness (coplanarity) of the lead pin 12 of the IC package 10 to be inspected can be detected.

Hereinafter, a method for inspecting the lead pins of the IC package according to the present invention using the above-described IC package lead pin inspecting apparatus according to the present invention will be described. The IC package 10 positioned in space with the suction nozzle 211 absorbs the light emitted from the light emitting sensors 221, 222 and 223 according to the state of the attracted position Since the state of being shielded by the lead pin 12 of the IC package 10 is changed, the amount of received light reaching the light receiving sensor 231 (232) 233 also becomes different. 6, the lead pins 12 of the IC package 10 have light-shielding regions of the minimum width arranged on the optical axis of the light-receiving sensor 233 outputted in the state of the largest amount of received light The flatness of the lead pin 12 is determined based on this.

Meanwhile, the sensor may be installed in an increased number, for example, 5 or 7 in order to increase the inspection accuracy according to the model, specification, etc. of the IC package to be inspected. However, 7, the distance L from the vertex of the curve to the X-axis is set to a minimum light-shielding width of the lead pin 12 (L), the flatness of the lead pin 12 can be detected. That is, in the case where three pairs of sensors are provided as in the present embodiment, the light receiving amounts detected by the light receiving sensors 231, 232, and 233 are substituted into the following equation (1) The width L is calculated.

Y = aX2 + bX + c

In Equations (1) and (7), Y (axis) is the width of difference and X (axis) is the angle formed by the axes of the emitted lights ). The unknowns a, b, and c are the installation angles (-) of the light receiving sensors 231, 232, and 233, , 0, (Y1, y2, y3) into the Y in the equation (1).

Since the minimum difference width L in Equation 1 is calculated as c-b2 / 4a (when X = -b / 2a), the angle value X (= -b / 2a) , C - b2 / 4a is taken as the value of the flatness of the lead pin by taking the minimum difference width, and if it is out of the range of the following formula (2) Wow Is taken as the flatness value of the lead pin.

≪ X = -b / 2a <

INDUSTRIAL APPLICABILITY As described above, the method and apparatus for inspecting lead pins of an IC package according to the present invention can improve accuracy and efficiency of lead pin inspection by correcting the position error of an IC package adsorbed on a suction nozzle.

Claims (7)

A component adsorption nozzle, And a plurality of light emitting sensors and light receiving sensors each having at least three odd numbered portions arranged in parallel with each other with a lead pin arranged on one side of an IC package which is sucked by the nozzle and located on a space, Wherein one of the plurality of light emitting sensors is provided so that light emitted therefrom can form a first optical axis parallel to a side of the body of the IC package and the other has an axis of light emitted therefrom, And the optical axes of the lights emitted from the respective light emission sensors cross each other at one point of the one side central portion of the body of the IC package, And a controller for detecting an alignment state of the lead pin by measuring an amount of light that is emitted from the light emitting sensor and is shielded by the lead pin and reaches the light receiving sensor. Inspection device. A plurality of light emitting sensors and light receiving sensors are arranged in a mutually parallel state with lead pins arranged in one side of the IC package interposed therebetween, and light is emitted from each of the light emitting sensors to corresponding light receiving sensors, The light emitted from each of the light emitting sensors is shielded by the lead pin, and the amount of light reaching the respective corresponding light receiving sensors is measured, Calculating an output value of the amount of light received by each light receiving sensor by a quadratic curve expression and calculating a minimum difference width of the lead pin from the angle value formed by the vertex of the quadratic curve and the axis of each light, And the lead pin is inspected. 3. The method of claim 2, And the light emitting sensor and the light receiving sensor are each provided with at least three odd number of the light emitting sensor and the light receiving sensor. The method according to claim 2 or 3, Wherein the light emitted from any one of the plurality of light emitting sensors forms a first optical axis parallel to a side of the body of the IC package and the optical axis of the light emitted from each of the plurality of light emitting sensors forms a predetermined angle with the first optical axis, Wherein a lead pin of the IC package is formed to be inclined with respect to a side of a body of the package. The method according to claim 2 or 3, Wherein the plurality of light emitting sensors are arranged so that optical axes of light emitted from the plurality of light emitting sensors cross each other at one point of a central portion of one side of the body of the IC package. 3. The method of claim 2, In the quadratic curve equation, Y = aX2 + bX + c (where Y is the width of the light, X is the angle of the light emitted from the light sources, and a, b and c are the Wherein an unknown value obtained by substituting a value of the received light amount and an angle formed by the axis of each light is expressed by an unknown number. 7. The method according to claim 1 or 6, The minimum light shielding width of the lead pin, Is calculated using the quadratic curve equation and the equation: X = -b / 2a <??.