CN1108636C

CN1108636C - Method and device for checking IC device shell pin

Info

Publication number: CN1108636C
Application number: CN97104651A
Authority: CN
Inventors: 卞钟垠
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 1996-09-24
Filing date: 1997-07-28
Publication date: 2003-05-14
Anticipated expiration: 2017-07-28
Also published as: JP2916447B2; KR19980022945A; KR100238269B1; JPH10107169A; CN1190793A

Abstract

To enhance the accuracy, the density and the efficiency of an inspection with reference to the alignment state of lead pins by a method wherein at least three pairs of light-emitting sensors and light-receiving sensors are installed so as to be faced by sandwiching a row of the lead pins at an IC package and the alignment state of the lead pins is inspected. A lead-pin inspection apparatus is provided with a suction nozzle 211 which sucks and picks up an IC package 10 and which can be moved, with three pairs of light-emitting sensors 221, 222, 223 and light-receiving sensors 231, 232, 233 which are installed so as to be faced in the arrangement direction of lead pins 12 at the IC package 10, to be sucked, by sandwiching a row of the lead pins and with a controller 240 which measures quantities of light emitted from the light-emitting sensors so as to reach the light-receiving sensors and which inspects the alignment state of the lead pins 12. Then, even when the IC package 10 is not sucked precisely by the suction nozzle 211, the quantities of received light obtained by the light-receiving sensors are used as a variable, a maximum light-receiving point is seached, and the alignment state of the lead pins is inspected.

Description

Check the method and apparatus of integral circuit packaging pin

Technical field

The present invention relates to a kind of method and apparatus of checking and estimating integral circuit packaging pin, particularly a kind of method and device of checking and estimating the layout state of platypelloid type integral circuit packaging pin.

Background technology

In general, platypelloid type integrated circuit encapsulation 10, such as quad-flat-pack (QFP) comprise that a main body 11 and several are arranged in the pin 12 of these main body 11 sidepieces, see Fig. 1.As shown in the figure, pin 12 comprises: encapsulate the extension 121 that main body 11 levels are stretched out certainly; The downward rake 122 that extends with a predetermined angular; And from rake 122 horizontally extending ends 123.

When integrated circuit encapsulation 10 was installed on the printed circuit board (PCB) (not shown), the attitude of all pins 12, direction, inclination angle and height all should be identical, so that all pins 12 all contact with circuit board.That is to say that when the integrated circuit encapsulation is installed on the circuit board, if the inhomogeneous unanimity of layout of pin 12, some pin 12 can not contact with plate 1, as shown in Figure 2.Like this, just can not correctly implement welding, thereby produce the substandard products element.For avoiding this phenomenon to take place, before the integrated circuit encapsulation is installed on the circuit board, tackles it and check, the layout of pin is estimated.Evaluation can be undertaken by the measurement to the isoplanar degree of pin.

See also Fig. 3 and 4, the traditional pin testing fixture that is used to measure pin isoplanar degree comprises: a suction nozzle 111 is used to fix integrated circuit encapsulation 10; One photophore 120; One detector 130, it and photophore 120 are faced and are separated by being arranged pin 12 by one of the integrated circuit of suction nozzle 111 fixings encapsulation 10; One controller 140 is used to measure pin 12 backs of passing through of being sent by photophore 120 and arrives the light quantity of detector 130, thereby the layout of pin 12 is estimated.

To place between photophore 120 and the detector 130 by the integrated circuit encapsulation 10 that suction nozzle 111 fixes.Under this state, light self-luminous device 120 directed toward detector of sending 130.At this moment, the difference in height that pin is 12 is big more, and the light that pin 12 stops is many more, and the light quantity that arrives detector 130 is few more.Thereby, by detecting the light quantity that arrives detector 130, can determine the isoplanar degree of the pin 12 of integrated circuit encapsulation 10.

But when utilizing above-mentioned traditional device that the pin of integrated circuit encapsulation is checked, for obtaining check result accurately, the arrangement of the sidepiece of integrated circuit package main body and pin end must be parallel to each other.Because above-mentioned inspection condition is difficult to satisfy, the accuracy of inspection descends.

In addition, as shown in Figure 5, if the integrated circuit that fixes by suction nozzle 111 encapsulation 10 and optical axis θ at angle, even the layout of pin 12 is very desirable, also there is a zone " B " to be covered, thereby reduced the light quantity that arrives detector 130 by sloping portion 122 (see figure 1)s of pin 12.When utilizing traditional method that pin is checked, be to compare the pin layout state of measuring by an absolute value and a reference value that detector is received light quantity.Thereby, even the integrated circuit encapsulation is fixed exactly, no matter the layout of pin how, is still judged this device defectiveness, i.e. reliability decrease of Jian Chaing.

Summary of the invention

The purpose of this invention is to provide a kind of method and apparatus of checking the pin layout in the encapsulation of platypelloid type integrated circuit, to address the above problem.Compare with traditional method, its accuracy is higher.

For realizing above-mentioned purpose of the present invention, a kind of device of checking the pin of integrated circuit encapsulation is provided, it comprises: a bracing or strutting arrangement, it is installed versatilely and rotatably to pick up the integrated circuit encapsulation; At least three pairs of photophore and detectors that face with each other and be provided with, row's pin of integrated circuit encapsulation and are met at a bit by the described optical axis that photophore and detector are formed between photophore and detector; One controller is used to measure that each photophore sends walks around pin and by between the pin and arrive the light quantity of each detector, thereby the layout of pin is checked.

For realizing above-mentioned purpose of the present invention, provide a kind of device of checking pin that utilizes to come the method that the pin of integrated circuit encapsulation is checked, described testing fixture comprises at least three pairs of photophore and the detectors that face with each other and be provided with, one row's pin of integrated circuit encapsulation and is met at a bit by the described optical axis that photophore and detector are formed between photophore and detector.Described method comprises step: the integrated circuit encapsulation is placed between photophore and the detector; Detect that photophore sends walk around pin and by between the pin and arrive the light quantity of detector; Utilize the optical axis angle of every pair of photophore and detector formation and the shading amount of pin to construct a function as variable; Try to achieve minimum of a function value and minimum optical axis angle; And and the maximum light income of minimum optical axis angle correspondence compare with a ginseng value, thereby the layout of pin is estimated.

Description of drawings

By reference accompanying drawing description of preferred embodiments, above-mentioned purpose of the present invention and advantage will become apparent.

Fig. 1 is a stereogram, shows a typical platypelloid type integrated circuit encapsulation;

Fig. 2 is a sectional view, the state when showing platypelloid type integrated circuit encapsulation and being installed in the substrate;

Fig. 3 is a stereogram, shows the device that the pin of integrated circuit encapsulation is checked in a kind of traditional being used to;

Fig. 4 checks the end view of the conventional apparatus of integral circuit packaging pin for shown in Figure 3 being used to;

Fig. 5 is a plane graph, shows the operation principle that the conventional apparatus of the pin that integrated circuit encapsulates is checked in shown in Figure 3 being used to;

Fig. 6 is a stereogram, shows the device that is used to check the pin of integrated circuit encapsulation according to of the present invention;

Fig. 7 is the plane graph according to the device of the pin that is used to check the integrated circuit encapsulation of the present invention;

Fig. 8 is a plane graph, shows the operation principle according to the device of the pin that is used to check the integrated circuit encapsulation of the present invention;

Fig. 9 is the function curve according to the method acquisition of the pin of inspection integrated circuit encapsulation of the present invention.

Embodiment

Please refer to Fig. 6 and Fig. 7, be used to check that according to of the present invention the device of pin comprises: suction nozzle 211, it is installed versatilely, to pick up and fixing one integrated circuit encapsulation 10; The setting that faces with each other of at least three pairs of photophores 221,222,223 and detector 231,232,233, photophore and detector is arranged between them by row's pin 12 of the integrated circuit encapsulation 10 of suction nozzle 211 fixings; Controller 240 is used to measure that each photophore 221,222 and 223 sends walks around pin 12 and by arriving the light quantity of corresponding detectors 231,232 and 233 between the pin 12 then, thereby the layout state of pin 12 is estimated.

The optical axis that is formed by photophore 222 and detector 232 has a θ angle with respect to the optical axis that photophore 221 and detector 231 form, and the latter itself also has a θ angle with respect to the optical axis that photophore 223 and detector 233 form.These three optical axis intersections are in " F " point.A head of suction nozzle 211 is supported in reference number 210 expressions among Fig. 6, and it can make suction nozzle 211 move and rotate.For example, after being positioned at pin 12 inspection that integrated circuit encapsulates 10 1 sides and finishing, head 210 removable or rotating nozzles 211 are checked with the pin to the opposite side that is positioned at integrated circuit encapsulation 10.

Head 210 can be mounted to and freely move by XY manipulator or articulated manipulator (articulated robot).Photophores 221,222 and 223 and the support component of detector 231,232 and 233 are supported in

reference number

220 and 230 expressions.

When the device of the operation pin that is used to check the integrated circuit encapsulation of the present invention, in the time of on the integrated circuit of examine encapsulation 10 places such as the workbench (not shown) of the common components feedway of drum-type feeder (bowl feeder) or orthoscopic feeder and so on, by the transducer (not shown) that is contained on the workbench head 210 is moved on on the workbench, head descends and integrated circuit encapsulation 10 is fixed then.

By moving-head 210, integrated circuit encapsulation 10 test zones that are positioned between photophore 221,222,223 and the detector 231,232,233 that will be fixed.

According to feature of the present invention, even suction nozzle 211 with integrated circuit encapsulation 10 fixing exactly, but utilizes one group of detector, 231,232 and 233 detected light quantities as a variable, residing position in the time of still can finding light income to be maximum.Describe the device of inspection pin in detail with three pairs of photophores and detector below with reference to Fig. 8.

Figure 8 shows that suction nozzle 211 is with integrated circuit encapsulation 10 situation of fixing exactly.In the case, the light quantity that arrives each detector 231,232 and 233 has nothing in common with each other.Like this, the angle of each optical axis be respectively θ °, 0 ° ,-θ °, when the shading amount is respectively F (θ °), F (0 °), F (θ °), by with angle θ °, 0 ° and-θ ° particular value as independent variable θ, and, can get following quadratic equation with shading amount F (θ °), F (0 °), F (θ °) particular value as dependent variable F (θ):

F(θ)＝aθ ²+bθ+c

Here, coefficient " a ", " b ", " c " are determined by the angle and the shading amount of optical axis.When minimum cut-off angle θ be-during b/2a, minimum shading amount " L " is c-b ²/ 4a sees Fig. 9.If minimum cut-off angle θ, promptly-b/2a, between-θ ° and θ °, then minimum shading amount is F (θ °) or F (θ °), and in these two selected amounts, one of them is less than another.

Minimum cut-off angle is exactly maximum acceptance angle, and this value has been represented the isoplanar degree of the pin of being checked.Here, the isoplanar degree is determined by this value and reference value are compared.That is to say that according to the present invention, no matter how the integrated circuit encapsulation is installed fixing by this, the detection limit that obtains with one group of photophore and detector is as variable, can draw a function, can obtain maximum acceptance angle and maximum light income by this function, thereby the layout of pin is estimated.Therefore, because maximum light income is a constant, so can do to check more reliably to pin.In this embodiment, quadratic equation is based on three pairs of photophores and detector establishment.But, must adopt the more function of high-order to using the photophore more than three pairs and the situation of detector.

Utilize the method and apparatus of the pin of above-mentioned inspection integrated circuit encapsulation, can improve the efficient that pin is checked accuracy and inspection, and encapsulate by the location independent of suction nozzle fixing with integrated circuit.

Claims

1. device that is used to check the pin of integrated circuit encapsulation is characterized in that it comprises:

One bracing or strutting arrangement, it is installed versatilely and rotatably to pick up described integrated circuit encapsulation;

At least three pairs of photophores and detector, they face with each other and are provided with and row's pin of described integrated circuit encapsulation is placed between the two, and by the described optical axis intersection that photophore and detector are formed in a bit; And

One controller, be used to measure that each described photophore sends, walk around described pin and by arriving the light quantity of each described detector between the pin then, to check the layout of described pin.

2. one kind is utilized the device of checking pin to come the method that the pin of integrated circuit encapsulation is checked, described testing fixture comprises at least three pairs of photophore and the detectors that face with each other and be provided with, one row's pin of integrated circuit encapsulation is between photophore and detector, and in a bit, described method comprises step by the described optical axis intersection that photophore and detector are formed:

The integrated circuit encapsulation is placed between photophore and the detector;

Detect that photophore sends walk around pin and by between the pin and arrive the light quantity of detector;

The optical axis angle that utilizes every pair of photophore and detector to form is constructed a function as independent variable with by the shading amount that described pin produces as dependent variable;

Try to achieve described minimum of a function value and minimum optical axis angle;

And will compare with a reference value, thereby the layout of pin is estimated with the maximum light income of minimum optical axis angle correspondence.

3. the method for the pin of inspection integrated circuit encapsulation as claimed in claim 2 is characterized in that described photophore and detector are three pairs, and described function is a quadratic function.