JP3386967B2 - Substrate inspection method - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for inspecting a substrate.

[0002]

2. Description of the Related Art The number of input / output terminals has increased as the degree of integration of semiconductors has improved. Therefore, a semiconductor package having a large number of input / output terminals has been required. Generally, I / O terminals are arranged in a row around the package,
There is a type that arranges not only the periphery but also the interior in multiple rows.
The former is QFP (Quad Flat Packag)
e) is typical. When the number of terminals is increased, it is necessary to reduce the terminal pitch, but in the area of 0.5 mm pitch or less, a high level technique is required for connection with the wiring board. The latter array type is suitable for increasing the number of pins because the terminals can be arranged at a relatively large pitch. Conventionally, the array type has a PGA (Pin Gri) having connection pins.
d Array) is generally used, but the connection with the wiring board is an insertion type and is not suitable for surface mounting. For this reason,
Surface mountable BGA (Ball Grid Arra)
A package called y) has been developed.

On the other hand, with the miniaturization of electronic equipment, there is an increasing demand for further miniaturization of the package size. To cope with this miniaturization, a so-called chip size package (CS
P; Chip Size Package) has been proposed. This is a package having a connection portion with an external wiring board in the mounting area, not in the peripheral portion of the semiconductor chip. As a specific example, a polyimide film with bumps is adhered to the surface of a semiconductor chip, an electrical connection is made between the chip and a gold lead wire, and then epoxy resin or the like is potted and sealed (NIKKEI MATERI).
ALS & TECHNOLOGY 94.4, No.
140, p18-19), or metal bumps are formed on the temporary substrate at positions corresponding to the connection portions of the semiconductor chip and the external wiring substrate, the semiconductor chip is face-down bonded, and then transfer molded on the temporary substrate ( Sm
allest Flip-Chip-Like Pac
case CSP; TheSecond VLSI
Packing Workshop of Japan
an, p. 46-50, 1994).

[0004]

However, most of the conventionally proposed semiconductor packages are not compact and capable of accommodating a high degree of integration, preventing package cracks, and being excellent in reliability and productivity. . The present invention provides a method of inspecting a package chip support substrate for preventing package cracks and capable of manufacturing a small semiconductor package having excellent reliability. The present invention provides a method for inspecting a chip support substrate for a semiconductor package, which allows the adhered state of the entire insulating film adhesive to be easily observed in a short time.

[0005]

A method of inspecting a substrate according to the present invention comprises: Wiring that Yusuke <br/> the semiconductor chip mounting area on one surface of the insulating support substrate is formed of two or more, the wiring of the semiconductor chip to the semiconductor chip mounting region through the insulating film adhesive material B. When mounted, a space is formed between the surface of the insulating film adhesive facing the insulating support substrate, the end surface of the second wiring, and the surface of the insulating support substrate, B. Wherein the insulating support substrate is at least one through hole is formed at a position that menses in the gap, C. A method for inspecting a supporting substrate for a semiconductor package, wherein an insulating film adhesive is formed on a portion where a semiconductor chip is mounted, including on the wiring in the semiconductor chip mounting region, and D. Liquid is injected into the void from a part of the opening of the void.
Then, E. Time for liquid to reach the through hole by capillary action
By measuring the time and the insulating film
Pre-measured according to the attachment status of the adhesive
-By comparing the time that was divided,
Insulating film-like bonding on conductor package support substrate
It is characterized by inspecting the adhering condition of the material .

As a package chip support substrate capable of preventing a package crack and manufacturing a small semiconductor package having excellent reliability, A. Two or more wirings having a semiconductor chip mounting area are formed on one surface of the insulating support substrate, and the wiring is insulated when the semiconductor chip is mounted on the semiconductor chip mounting area via an insulating film adhesive. A surface of the adhesive film adhesive facing the insulative support substrate, the wiring end face of the second wiring, and the surface of the insulative support substrate are arranged to form a space, and B. At least one through hole is formed in the insulating support substrate at a position facing the void, and C.I. There is a chip support substrate for a semiconductor package, in which an insulating film adhesive is formed, at a position where the semiconductor chip is mounted, including on the wiring in the semiconductor chip mounting region.

In this semiconductor package chip support substrate, when the insulating film adhesive material adhered to the semiconductor chip mounting portion is adhered (it is adhered in a tent shape between wirings to form a void connected to the through hole). It is important to note that it is impossible to fully observe the state of the insulating film adhesive after it has been attached. It takes a lot of time and labor to observe a chip supporting substrate for a semiconductor package by casting it with epoxy resin or the like, cutting the cross section, and observing only one cross section. However, it is very difficult to observe the entire pasted state, but the inspection method of the present invention can easily observe the entire pasted state of the insulating film adhesive. In the present invention, the opening of the void corresponds to a gap between the through hole and the wiring.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION As the insulating support substrate, a plastic film of polyimide, epoxy resin, polyimide or the like, or a material such as glass nonwoven fabric impregnated and cured with a plastic of polyimide, epoxy resin, polyimide or the like can be used. . In order to form a plurality of sets of wiring on one surface of the insulative support substrate, a method of etching a copper foil, a method of plating copper at a predetermined place, a method of using them in combination, and the like can be used. The through holes can be formed in the insulating support substrate by mechanical processing such as drilling or punching, laser processing such as excimer laser or carbon dioxide laser, and the like. Also, an opening is provided in advance on an adhesive insulating base material and the like, and it is attached to a metal foil for forming a wiring such as copper foil, or an opening is provided on an insulating base material with a copper foil or in which wiring is formed in advance. It is possible to provide them and to use them together.

In the semiconductor chip mounting area, it is preferable that the wiring patterns are arranged as uniformly as possible. Specifically, the insulating support substrate in the semiconductor chip mounting area,
It is preferable that the wirings are arranged so that at least one wiring is formed in a range of a radius of 1 millimeter including the arbitrary point. However, if such a condition cannot be satisfied only by wiring, an independent dummy pattern, a positioning mark, a metal pattern such as characters / codes may be separately provided.

As the insulating film adhesive, a plastic film made of polyimide, epoxy resin, polyimide or the like coated with an adhesive on one or both sides, or a single-layer insulating film adhesive can be used. As a single-layer insulating film adhesive, for example,

[Chemical 1] (However, the integer of n = 2-20 is shown.) The tetracarboxylic dianhydride whose content of the tetracarboxylic dianhydride (1) is 70 mol% or more of all the tetracarboxylic dianhydrides. And a polyimide resin obtained by reacting a diamine, and a film adhesive made of a thermosetting resin such as an epoxy resin. Further, an inorganic substance filler such as silica or alumina may be contained therein.

Regarding the thickness of the single-layer insulating film-like adhesive material, the thinner it is, the easier it is to attach in a tent shape, as long as the insulation between the semiconductor chip and the wiring can be secured. Specifically, 0.005 mm or more and 0.030
mm or less, and more preferably 0.010 mm or more and 0.020 mm or less. When using an insulating film coated with adhesive,
Similarly, the thickness of the adhesive layer is preferably thin. At least one through hole is formed in the insulating film adhesive mounting region. The hole diameter is not particularly limited, but for example, 0.
It is preferably at least 05 mm and at most 1.000 mm. The arrangement is not particularly limited, but it is preferable that a plurality of them are arranged as evenly as possible, and the hole diameter and the arrangement thereof are selected according to the wiring pattern.

The liquid used for the inspection is not particularly limited, but it has an appropriate viscosity and surface tension in consideration of the materials of the insulating support substrate and the insulating film-like adhesive, and the space between voids. Must be selected. The viscosity is preferably 0.003 to 1 P, more preferably 0.01 to 0.1
P is more preferred. Further, in order to make the injection state of the liquid into the voids easier to observe, a coloring matter, a fluorescent substance or the like may be added to the liquid.

As an example of manufacturing a semiconductor package using a semiconductor package chip support substrate, first,
A semiconductor chip is mounted on the surface of the insulating film-like adhesive material of the semiconductor package chip support substrate. At this time, if the chip mounting surface of the insulating film adhesive has an adhesive function, it can be mounted as it is, but a paste die-bonding adhesive can also be used together. Next, the semiconductor chip electrode is connected to the inner connecting portion of the supporting substrate by wire bonding or the like. Further, at least the semiconductor chip electrode surface of the semiconductor chip is resin-sealed, and solder balls are mounted on the outer connecting portions, whereby a semiconductor package can be manufactured.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. An outer connecting portion 3 and a through hole (vent hole) 9 are formed by drilling in a polyimide bonding sheet 1 having a thickness of 0.07 mm in which both sides of a polyimide film are coated with a polyimide adhesive material. Next, thickness 0.
018mm copper foil (Nippon Electrolytics, trade name: SLP-1)
After 8) is adhered, the inner connection portion and the developed wiring 2 are formed by a usual etching method. Further, the exposed wiring is sequentially subjected to electroless nickel plating (film thickness: 5 μm) and electroless gold plating (film thickness: 0.8 μm) (not shown). Although electroless plating is used here, electrolytic plating may be used. Next, using a punching die, it is punched into a frame shape to prepare a support substrate on which a plurality of sets of inner connecting portions, developed wirings, and outer connecting portions are formed (Fig. 2a). As a method of manufacturing the support substrate, a commercially available two-layer (copper / polyimide) flexible substrate of polyimide may be used to form the outer connection hole and the like by laser processing.

Next, in the semiconductor chip mounting area of the support substrate,
Die bond film 4 (manufactured by Hitachi Chemical Co., Ltd., trade name: DF-335, thickness 0.015 mm) is adhered (Fig. 2b). The oil 12 (with a viscosity of 0.0
5 poises) and oil 12 is injected from the opening of the void by utilizing the capillary phenomenon (FIG. 1). The time taken for the oil 12 to reach the through hole 9 of the support substrate was measured, and those within 3 minutes were group A (those in good tent condition) and those within 5 minutes were group B (somewhat bad tent condition). The above is set as C group (the tent is in a bad state), and three kinds of samples in the attached state are prepared by changing the attaching conditions. Next, with respect to the samples of each group, the semiconductor chip 6 was adhered to a predetermined position of the supporting substrate using a silver-free paste (manufactured by Hitachi Chemical Co., Ltd., trade name: EN-4322) on the adhered die bond film. , 180 ℃,
After-curing for 1 hour, the die bond film and the silver-free paste are cured. Further, the semiconductor chip electrode and the inner connecting portion are electrically connected by bonding the gold wire 5 (FIG. 2c). The thus-formed product is loaded into a transfer mold die, and epoxy resin 7 for semiconductor encapsulation (manufactured by Hitachi Chemical Co., Ltd., trade name: CL
-7700) for sealing (FIG. 2d). After that, the solder balls 8 are placed on the outer connection portion and melted (FIG. 2e), and separated into individual packages by punching to obtain semiconductor packages (FIG. 2f). After three days of moisture absorption (30 ° C / 75% RH), IR reflow (230 ° C,
The test which performs 5 seconds) was performed for 2 cycles. The results are shown in the table below.

Number of occurrences of reflow cracks Group 1st reflow 2nd reflow ─────────────────────── A 0/7 0/7 B 2 / 7 3/7 C 3/3 3/3 ─────────────────────── In this way, according to the inspection method of the present invention, the die bond film is attached. It was confirmed that the sample of group A, which was judged to be in good condition, had good reliability and that this test method was an effective means.

[0017]

【The invention's effect】

a. Forming a plurality of sets of wirings (having at least an inner connecting portion for connecting to a semiconductor chip electrode and a semiconductor chip mounting region portion) on one surface of the insulating support substrate; b. An opening is provided in a portion of the insulating support substrate where the wiring of the insulating support substrate is formed and where an outer connecting portion that is electrically connected to the inner connecting portion is provided, c. Providing one or more through holes in the non-wiring semiconductor chip mounting area of the insulating support substrate, d. Forming an insulative film in a place where a semiconductor chip is mounted, including a semiconductor chip mounting area part of wiring; e. Adhering the semiconductor chip to the surface of the support substrate on which the inner connection portion is provided, f. Connecting the semiconductor chip electrode to the inner connection portion of the substrate by wire bonding, g. In a semiconductor package manufactured by sealing at least the semiconductor chip electrode surface of a semiconductor chip with a resin, it is important to attach an insulating film adhesive to the support substrate to ensure high reliability. In order to fully utilize the function of the (vent hole), it is necessary to attach the insulating film adhesive material in a tent shape between the wirings to form a gap between the insulating film adhesive material and the supporting substrate. According to the present invention, the adhering state of the insulating film adhesive can be easily judged in a short time, and the inspection of the supporting substrate for manufacturing a highly reliable small semiconductor package is significantly speeded up. Was done.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a semiconductor package manufacturing process which is an object of the present invention.

[Explanation of symbols]

1 Polyimide bonding sheet 2 Inner connection part and development wiring 3 Outer connection part 4 die bond film 5 gold wire 6 semiconductor chips 7 Epoxy resin for semiconductor encapsulation 8 solder balls 9 Through holes (vent holes) 10 Silver-free paste 11 Semiconductor package area 12 oil

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-10-135247 (JP, A) JP-A-10-163256 (JP, A) JP-A-10-189820 (JP, A) JP-A-9- 148475 (JP, A) JP-A-10-223795 (JP, A) International Publication 98/19338 (WO, A1) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 21/52 H01L 21 / 66 H01L 23/12 501 H01L 21/60 301 H01L 21/60 311

Claims (2)

(57) [Claims] 1. A. Wiring that having a semiconductor chip mounting area on one surface of the insulating support substrate is formed of two or more, the time the wire in which a semiconductor chip is mounted on the semiconductor chip mounting region through the insulating film adhesive material The insulating film adhesive is arranged so that a gap is formed between the surface of the insulating film adhesive facing the insulating support substrate, the wiring end surface of the second wiring, and the surface of the insulating support substrate. Wherein the insulating support substrate is at least one through hole is formed at a position that menses in the gap, C. A method for inspecting a supporting substrate for a semiconductor package, wherein an insulating film adhesive is formed on a portion where a semiconductor chip is mounted, including on the wiring in the semiconductor chip mounting region, and D. Liquid is injected into the void from a part of the opening of the void.
Then, E. Time for liquid to reach the through hole by capillary action
By measuring the time and the insulating film
Pre-measured according to the attachment status of the adhesive
-By comparing the time that was divided,
Insulating film-like bonding on conductor package support substrate
A board inspection method characterized by inspecting the adhering condition of materials . 2. The method for inspecting a substrate according to claim 1, wherein the viscosity of the liquid is 0.003 to 1P.