TWI263801B - Detection method for warpage of semiconductor packages - Google Patents

Abstract

A detection method for warpage of semiconductor packages comprises the following steps: mounting a reference grating above a position where the semiconductor package is positioned; providing a predetermined light to pass through the reference grating so that a grating shadow is projected on the semiconductor package; capturing an image of a moire phenomenon of the grating shadow caused by the reference grating in a video camera module; moving the reference grating to at least two predetermined phases to capture at least two different images of moire phenomenons; calculating the images to obtain a serial-phase image; and then processing the serial-phase image so as to obtain a reference numeral appearing warpage of the semiconductor package.

Description

I2638〇i IX, invention description: [Technical field of invention] This I is related to a kind of dreams... The special system is about the specific detection of the curvature of the curve. Pair-to-test package into the method. Inspection of the surface warpage value of the Λ Temple 4 package [Prior Art] The value method _ the appropriate optical principle (for example, the triangle is: the needle, and the surface of the matching body is micro), the wire changes. However, 1^fine-package to be tested: the method of measuring the point measurement _ the method of detecting the light-piercing method of the plug-in is also relatively small. Therefore, = plus point-by-point measurement time increase and failure to implement the global two =: leading to the high precision, long-stroke position of the optical probe method, thus increasing the cost of the domain II. It is necessary to "accurate but the illusion of the sorcerer has a higher measurement accuracy, so the structure of the light is a light source and requires a higher precision optical machine, and the cost of the production equipment is relatively increased. Detecting environmental requirements. In addition, the material is relatively low in detection cost, detection environment requirement and high detection efficiency compared with the needle method and micro-interference 1 , but = in practice, due to the use of conventional embossing The method generates too much noise in the detection step of phase reconstruction, thus relatively extending the mathematical calculation method C:\Linda\PK Pat\PK97TZ doc

05/12/07/10:20 AM ——5~ !263801 ^The day guard, so as to reduce the detection efficiency. Therefore, it is necessary to improve the above-mentioned warpage value of the difficult county. It is necessary to improve the above disadvantages in view of the fact that the present invention improves the above-mentioned disadvantages, and the embossing method is combined with a specific image processing method to quickly go to the above-mentioned medium. The generated noise "can relatively improve the detection efficiency and:::= [Summary of the content] The county is responsible for the purpose of storage and supply - the county taxation = test method, which will be - reference grating relative - to be tested dragon body = Specially, she took a few shadow overlays to calculate the effect of the confirmation.升 detection efficiency and detection fine ^ ^ invention * to provide the purpose of providing _ kinds of county and county speed detection method, which uses image segmentation, image pre-processing (such as two = = method, thin line method), image object recognition and The decision-reaction and other image i-measurement package phase reconstruction, so that the invention has the effect of reducing the transportation of different materials and improving the detection efficiency. Another object of the present invention is to provide a rapid detection method for the surface curvature value of a package, which is to provide a similar parallel light through a fiber to a telecentric lens (tel_riC), so that the invention has the cost of reducing equipment. efficacy. The present invention further provides a method for rapidly detecting the warpage value of a package body, which uses at least an i-electric material to control the phase shift distance of a reference light thumb. The invention has improved phase shift distance accuracy and detection. Accuracy C:\Linda\Pk· Pat\PK9772 doc

〇5/12/〇7/1〇: 2〇 AM —6 — -1263801. The method for quickly detecting a package warpage value according to the present invention comprises the steps of: setting a reference transmission to a top of a county body; and using a reference line to form a shadow grating on the surface of the county to be tested; Using an image capturing module to capture the shadow grating formed by the reference grating and the shadow grating; moving the reference grating to the mosquito = after 'using the same method to capture another at least two shadow overlays; calculating the plurality of shadows The moiré obtains a phase image; and performs image processing on the phase image to obtain a surface warpage value of the package to be tested. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features, and advantages of the present invention will become more <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; As shown in FIGS. 1 and 2, the first step of the method for rapidly detecting the warpage value of the surface of the package according to the preferred embodiment of the present invention is disclosed. The reference grating 20 is disposed above a package to be tested 6. As shown in FIG. 2, the rapid detection structure of the surface warpage value of the package of the present invention comprises a carrier 1, a phase shifting mechanism 2, a light source 3, an image capturing module 4 and a grain unit 5. . The carrier 1 is used to carry the package 6 to be tested, and the carrier 1 may be selected from a conveyor such as a conveyor belt or a static carrier platform. The phase shifting mechanism 2 is configured to combine the reference grating 2 to move the kite grating 20 relative to the package to be tested 6 . The reference peach 20 can select an appropriate stripe density according to the required detection accuracy, for example, 20 lines/mm [bars/mm] or 4 lines/mm. The light source 3 is used by C:\Linda\PK Pat\PK9772. doc 〇5/12/〇7/i〇;2〇-7 763801

The reference grating 20 is illuminated, and the light source 3 can be selected from a laser source, a halogen source, and the like. The light source 3 is preferably selected from the group consisting of a light source, a plurality of optical fibers, and a telecentric lens. The halogen light source is guided to the telecentric lens via the optical fiber to provide a similar parallel light, thereby relatively reducing the device. cost. The image capturing module 4 is preferably selected from a photosensitive coupled device (CCD) image capturing module for capturing the reference grating 2 itself and the reference grating 20 in the package to be tested. The image of the shadow formed on 6. The loading unit 5 is provided with a feeding portion 51, a good product portion 52 and a defective product portion 53. The feeding portion 51 is for holding the package to be tested 6, and the good product portion 52 and the defective product portion 53 are respectively It is used for recovering the good products and defective products after the detection of the package 6 to be tested. The package to be tested is preferably applied to an integrated circuit (integrated drcuit, IC i&amp; ij completes the inspection of the colloid, such as the detection of a Ball Grid Array (BGA) type package. Referring to Figures 1 to 7 and the accompanying drawings la, which disclose the second and third steps of the method for rapidly detecting the warpage value of the package body according to the preferred embodiment of the present invention, the light source 3 is used to illuminate the reference a grating 2 〇 to form a shadow grating on the surface of the package 6 to be tested; and using an image capture, the group 4 captures the reference grating 2 〇 together with the shadow grating to form a shadow «pattern [such as the attached la Show]. Thereby, when the light source 3 illuminates the reference grating 20%, the shadow grating is formed on the surface of the package to be tested 6 below the reference grating 2〇. At the same time, since the surface of the package to be tested 6 is completely flat, the stripe pitch and relative position of the shadow grating are different from the reference grating 6. In addition, as shown in Fig. 3, the light source 3 and the shadow C:\Linda\PK PBt\PK9772. doc 05/12/07/10:20 - 8 - 1263801 are set between the capture module &lt;5 One of the central corners is set at 45. As shown in Fig. 4, the light source 3 can find the light-transmitting portion of the grating 2〇, and after the reflection of the agricultural body to be tested, the reference gratings HA, C, E, the a, c, E three points form a bright spot; 2; =: 6 surface B, D: riding (four) axis ginseng = light transmission at the point of control to form a dark spot. As shown in the fifth, the surface displacement value of the package 6 is measured as a plane [Formula 1], as follows:

Ng = Wtana + Wtanj3 where: W: represents the out-of-plane displacement value of the body 6 to be tested. 3 represents the stripe number (ie, the Nth stripe), which is the distance to be measured, installed, and the reference grating 2〇 is 〇 (ie, a point) is defined as a strip, and the text order, N - 〇, due to The e of the surface of the package to be tested 6 is located in the second bright line, and the stripe number is N=2. g · The density of the reference grating 2〇. α : represents the angle between the incident beam and the normal of the reference grating 20 . Called. Represents the angle between the image capture module 4 and the reference raster 2〇 normal. Then, after formulating the formula 1, the formula 2 can be obtained as follows: __Ns tana + tan C:\Linda\PK Pat\PK977Z doc

05/12/07/10:20 AM [2] I2638〇i as shown in Fig. 6, if the light source 3 and the image capturing module 4 have the same distance L from the package 6 to be packaged, and The distance between the light source 3 and the image capturing module 4 is D, and Equation 3 can be obtained as follows: tana + tan^z=_A_ [3]

L + W where, if W « L, then Equation 3 can be broken down to Equation 4, as follows: 9 L Next, after taking Equation 4 into Equation 1, Equation 5 can be obtained, such as tana + tan^ D 〔 4] Next: [5] %;&gt; Then the formula follows: 'If the design of the detection mechanism of the present invention is D = L, it can be simplified to Formula 6, as follows: 'Λ (4) Leather, if the light source 3 is changed to parallel Light, it can solve the problem that the money ~uN is not proportional to the package_6. Please refer to the show. For example, the 44# μ and 9 diagrams show a fourth step of the method for quickly detecting the curvature of the present invention, and after the external phase 2G moves a specific phase, the method of marriage is used to capture another Show, this; = pattern [as shown in the attached picture]. As shown in Fig. 9, at least the second shifting mechanism 2 is provided with a support block 21, a grating holder U member 23 and at least one elastic member 24. The support block 2ι C:\Linda\PK Pat\PK9772· doc

05/12/07/10:20 AM —10 — 1263801 is used to support the light by a. The aperture a is formed to incorporate the reference grating 20, and the grating frame 22 is placed on the support block 21 by the piezoelectric element 23 and the elastic element ^4, 'α σ °. Therefore, by controlling the piezoelectric element = 3, the lifting height of the grating frame 22 can be controlled. In this way, the image capturing module 4 can capture the shadow overlays of several different phases for the subsequent phase (4) calculations to further improve the detection. In addition, the phase of the phase shifting mechanism 2 is preferably Γ/2. A heart &amp; 1 and the accompanying le, which discloses the fifth step of the method for quickly detecting the surface value of the preferred package of the present invention, the basin system, the nose and the number of shadow overlays [such as the attached la Stripe to ld

Kx, y) = I 〇 (x, y) * {i + r (x5y) cos [ φ { where: (γ): represents the coordinate value of each pixel in the phase image. degree. Represents the image intensity at the coordinate value of the phase image, t, y): the image of the image is located at the back of the image of the special value 7 (x, y): represents the amplitude of the light intensity. : Two represents the phase value of each pixel in the phase image. The phase value of each pixel is made, y), and the number is obtained. If the pattern is to be folded, and the present invention preferably captures at least: the shadow of the shadow is reduced to reduce C:\Linda\PK. Pat\PK9772. doc

05/12/07/10:20 AM ~ 11~ Ϊ263801 The phase value of the prime indicates the error. Thereby, each image of the phase image [Equation 7] can be obtained as follows:

[8] In addition - engraved 光栅 2G grating 2G each time moving the μ phase, a total of at least three movements, to take at least four to divide the job \ this method can be referred to as the four-step method]. Then, the four shadows are overlaid by the formula 7, and the phase image is obtained. Please refer to the first! And the accompanying drawings, which disclose the sixth step of the method for detecting the surface tortuosity value of the package body of the present invention, which is a sixth step image of the anger wheel gf system (as shown in the attached 1e) for image processing (ie, Phase reconstruction processing] to obtain the surface tortuosity value of the county body 6 to be tested. At this time, the image processing includes steps (1) and shadow (four): the money is pre-separated from the area to be processed by the pool to reduce the amount of data and the operation time. In the present invention, the image segmentation system uses the region of interest method [regk]n (10)], that is, the package to be tested 6 is pre-clamped to calculate for the region of the weight to be processed. [2], image pre-processing: When there are too few features on the target image (such as a thick line at the phase of the performance) or too much (such as noise), the basin 2 selects (4) for her image selection. Preferably, the shadow p process of the present invention may include a binary method (ie, a grayscale value segmentation method), a thin, and a grayscale value of the phase image in the phase image (ie, 255 C:\Linda) \PK Pat\PK977^ doc

05/12/07/10:20 AM —12 — 1263801=Interval] Set a value; if the gray level value of a specific part of the phase image is large, the value of this value is defined as a bright point (ie gray level value 255) If the grayscale value is 7阙, it is defined as a dark point (ie, the grayscale value is 0). The thinning method is used to obtain the skeleton of the phase image (as shown by the attached lf). (1) Image object recognition: It will be identified by the binary method and the thin line 2 [R_n G_ing]. The growth method of the region includes steps: [a], slave growth core, [criteria And U], calculation progress. Among them, (5), determine ^ core. As attached ig*, since all the scorpions are concentric 2Ϊ, the growth core of the first zone can be set at the center of the image: set. (1) Given the same-valued criterion·· As shown in the attached picture lg, since the stupidity has only dark points (ie, gray-scale value G) and bright points (ie, gray-scale value 255), the bits are not continuous. In this way, the same-valued criterion is set by the growth core to be the same as the dark spot until the white point is encountered. [c], II. As indicated in point lh, those who meet the conditions of the same-valued criteria are: and two. 2 The search for a district and the search for all the second districts begins with the growth core and ignores the “,,,,,,,,,,,,,,,,,,,,,,,,,, Analogy to find the rest of the area. ... Image [such as attached π&quot; η Temple body 6 phase unfolding overlay [such as 5 + 'experimental financial towel found the shadow 2 two movements: shown] in the phase shift [this The invention moves from the lower to the higher, and the phase is C:\Linda\PK Pat\PK9772 doc —13 ~ 05/12/07/10.-20 Α« 1263801, = the relative height of the image. Then, according to the relationship between the regions, the relationship between the two is 27 y. That is, y accurately obtains the phase value of each point, and then obtains the phase-expanded image, and then finds the highest phase value and the lowest value of the phase-expanded image. Phase value. 'To subtract the two values, the surface value of the package to be tested can be obtained from the above formulas to obtain a three-dimensional image (as shown by the attached π) 〇, ... as described above The detection method of the county’s financial auditory value is based on the use of optical probe method, microscopic interferometry or embossing method. The county high and the measurement _ long turn point, the first picture of the creation of the storage by the reference grating in a number of specific phase shadow overlay, to calculate the phase image, and the specific image processing of the phase image The disc can improve the detection efficiency and the detection accuracy relatively. I Although the present invention is not difficult to implement the present invention, it is not intended to limit the present invention, and anyone skilled in the art can avoid the spirit of the present invention. Within the scope of 'there are various changes and modifications', the scope of protection of the present invention is subject to the definition of the scope of the patent application. C:\Lind8\PK PatvPK977i doc —14 —

05/12/07/10:20 AM 1263801 [Simple description of the drawing] Fig. 1 · The package diagram of the present invention. &amp; Quick detection method for the value of the clothing surface. Fig. 2 · The package of the present invention. The rapid detection structure of the surface warpage value: Front view Fig. 4 The rapid detection structure of the surface warpage value of the X-month package. Fig. 4························ The rapid detection method of the value is shown in Fig. 5: the fourth front [η. Brother 6 Figure · The schematic diagram of the package inspection operation of the present invention. 4_Quick value detection method into the younger brother 7: The package of the invention uses the parallel light riding detection operation d (four) value of the rapid detection method mining, not thinking. Figure 8: Side view of the present invention when the phase shift is applied. The front view of the phase shift mechanism of the rapid detection structure of the surface of the package on the surface of the moon. See nickname &amp; 2 attached la to Id: a shadow overlay image captured by the encapsulation method of the present invention. <Time private profit v Γ Γ, Γ * Invention seal | body surface (four) value of the rapid detection method to calculate the phase image of the nose. Attached: The rapid detection method of the surface warpage value of the hair _ (4) uses the skeleton of the phase image calculated by the thin line method. ::\Linda\PK Pat\Pi977Z doc

05/12/07/10:20 AM 15 1263801 Attached lg: The method for quickly detecting the warpage value of the surface of the package of the present invention. Attachment lh: The area segmentation schematic image calculated by the rapid detection method of the surface warpage value of the package of the present invention. Attached Li: The phase unwrapped image calculated by the rapid detection method of the surface warpage value of the package of the present invention. Attachment lj: A three-dimensional image produced by the rapid detection method of the surface warpage value of the package of the present invention. [Main component symbol description] 2 Phase shifting mechanism 21 Support block 23 Piezoelectric element 3 Light source 5 Container unit 52 Good part 6 Package to be tested 1 Carrier seat ~ 20 Reference grating Fun J 22 Grating stand 24 Elastic component 4 Image capture Module 51 feeding section) 53 defective parts

Claims (1)

1263801 X. Patent application scope: The rapid detection method of the _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Shadow raster, The method includes a step of extracting a shadow shadow of the reference light and the shadow formed by the image capturing module in the image capturing module to be tested; κ=refer to the λ gate to move a specific phase, and using the same method to capture In addition, at least two shadow overlays; force calculation of the number of gift shadows, Dina - she For the phase of the ride, the surface warpage value of the rider is changed. According to the application for the rapid detection structure of the surface warpage value of the county body described in the article Wei Wei, the system includes a carrier, a phase shifting mechanism, a light source and an image capturing module. To carry a package to be tested, the phase shifting mechanism moves the reference grating, and the light source uses, and emits the reference grating, and the image capturing module is configured to capture the reference grating and its shadow. 3. The rapid detection structure of the county wire whose value is described in the section of the “Fei·Feng·Wei 丨 丨 ' 其 其 其 其 其 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容 容And a defective product department. 4. The method for quickly detecting the surface (four) value of the package body according to the application of the patent (4), wherein the phase shifting mechanism is provided with a support grating and a grating C:\Linda\PK Pat\PK9TT2. doc 05/12/07 /10:20 AM —17 — 1263801 = at least a piezoelectric element and at least one elastic element, the grating frame is coupled to the support block by the piezoelectric element and the elastic element, and the piezoelectric element is used To control the movement of the grating. 5 According to the patent, the surface curvature value of the package described in item i is fast, and the light source can be selected from the laser source and the light source 〇6 according to the first item of the patent scope. The surface of the package is fast The speed 1 method, wherein the light source has a -3⁄4 source, a plurality of fibers, and a telecentric lens, the fiber guiding the light from the source to the telecentric lens. 7. The rapid detection method of the package curvature value according to the first aspect of the patent scope, wherein the light source and the image capturing unit have an angle between them. 8. According to the application, the rapid detection method of the package age warping value described in Item 7 is applied, wherein the angle is 45. . The method for rapidly detecting the surface warpage value of the package body according to the first aspect of the patent application, wherein the distance from the light source to the image capturing module is substantially equal to the light source and the image capturing module to the reference grating vertical distance. 10. A rapid detection method for the surface warpage value of the package according to item 1 of the patent application scope, wherein the reference grating is moved at a position of 7Γ/2 11 for each movement, and the package according to the first item of the patent application scope A rapid detection method for the surface warpage value, wherein the image processing is selected from the image segmentation, before the image C:\Linda\PK Pftt\PI977Z doc —18 — 05/12/07/10:20 AM 1263801 Processing, image Object identification, decision response. 12. The rapid detection method of the surface warpage value of the package according to claim 11 of the patent application scope, wherein the image segment is selected from the key area method. 13. The rapid detection method of the surface warpage value of the package according to Item 11 of the patent application scope, wherein the image pretreatment is selected from the group consisting of a binary method and a thin line method. 14. The rapid detection method for the surface warpage value of the package according to claim 11 of the patent application scope, wherein the image object identification system is selected from the group growth method 15. The rapid detection method for the surface warpage value of the package according to item 14 of the patent application scope wherein the growth method of the region comprises the steps of: determining the growth core; determining the same value; and calculating the advancement. C:\Iinda\PK Pat\PK977Z doc —19 — 05/12/07/10:20 AM