JP2589019B2 - Carrier tape for packaging chip-type electronic components - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a package having a function of protecting chip-type electronic components from contamination, and aligning and taking out the chip-type electronic components for mounting on electronic circuit boards when storing, transporting and mounting the chip-type electronic components. The present invention relates to a plastic carrier tape having a storage pocket.

[0002]

2. Description of the Related Art In recent years, transistors such as ICs, transistors, diodes, capacitors, piezoelectric element resistors,
Chip-type electronic components for surface mounting, such as packaging, consist of a plastic carrier tape that continuously forms embossed pockets that can be stored according to the shape of the electronic component, and a cover tape that can be sealed to the carrier tape. It is supplied packaged in the body. The electronic components of the contents are transported and stored in a state of being housed in a carrier tape, and after the cover tape of the package is peeled off, they are automatically taken out and surface-mounted on an electronic circuit board. With the development of the surface mounting technology, electronic components to be formed into chips are gradually expanding from mechanical components to highly integrated components such as ICs and LSIs. These highly integrated components can cause cracks during solder mounting when the sealing resin that protects the electronic circuit absorbs atmospheric humidity, which is a major problem. After passing through a baking process, it is taped on a carrier tape, sealed in an Al moisture-proof bag called a dry pack, and transported and stored to prevent moisture absorption. In addition, since it takes time to mount the electronic components in one reel of the carrier tape during mounting, it is necessary to repeat the process of transferring to a tray again, baking and using the tray. For this reason, the process is complicated and the carrier tape is further wrapped and re-baking is performed twice, and it is strongly desired to simplify the process while maintaining moisture proof of the product. In addition, since the material molded for the carrier tape is mainly selected for its moldability that can correspond to the shape of various electronic components, it has no moisture proof function and is not a material having heat resistance higher than the baking temperature.

[0003]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention has been intensively studied in order to obtain a carrier tape having a moisture-proof function while maintaining moldability into various embossed shapes. As a result, it is preferable that at least one layer of the carrier tape is a thermoplastic resin having good moldability and at least the other layer is formed of a composite sheet of two or more layers made of a metal layer having a moisture-proof function. The present inventors have found that the present invention has excellent characteristics, and have completed the present invention.

[0004]

The present invention provides a plastic embossed tape in which storage pockets for storing chip-type electronic components are continuously formed, wherein at least one layer of the carrier tape is made of an amorphous polyester. (Amorphous P
ET), polyurethane (PU), polypropylene (P
P), polystyrene (PS), polycarbonate (P
C), an embossable thermoplastic resin selected from ABS, polyacrylonitrile (PAN), and polyvinyl chloride (PVC), and at least the other layer is formed of Al,
It is a composite sheet of two or more layers of any of Cu, Zn, Sn, Ni, Ti or a compound thereof, and the moisture permeability of the composite sheet is JIS Z 0208 40 ° C., 90% R
1.5 g / m ² · 24 hr or less as measured by H
This is a chip-type electronic component packaging carrier tape which is excellent in moisture proofness and suppresses moisture absorption of electronic components in pockets during a product transportation / storage process.

[0005]

The constituent elements of the carrier tape 1 of the present invention will be described with reference to FIG. 1. The first layer 2 is made of crystalline polyester, amorphous polyester, polyurethane, polypropylene, polystyrene, polycarbonate, ABS, polyacrylonitrile, or polyvinyl chloride. Either, thickness is 50-4
It is a thermoplastic resin that can be embossed and has a thickness of 00 μm. 5
If it is 0 μm or less, the sheet strength is insufficient, and if it exceeds 400 μm, the moldability is significantly reduced. The second layer 3 is made of Al, C
u, Zn, Sn, Ni, Ti or a compound thereof, and is a metal layer having a moisture-proof function with a thickness of 1 to 50 μm. When the thickness is less than 1 μm, the moisture-proof function is insufficient.
If it exceeds 50 μm, the moldability will be significantly reduced and the cost will be increased. The metal layer is formed by a method such as adhesion of a metal foil, deposition of a metal or metal oxide, sputtering, or ion plating, and any method may be used, and there is no particular limitation. The side of the first layer 2 in contact with the second layer 3 or the side of the second layer 3 in contact with the first layer 2 is provided with a corona treatment, a plasma treatment, a sand blast treatment, and a chemical treatment for the purpose of improving the adhesion between the two layers. Surface treatment such as treatment may be performed. For the same purpose, both may be laminated via a thermosetting adhesive layer of isocyanate type, imine type or the like. For the purpose of imparting antistatic performance, an antistatic agent, a conductive powder or the like may be kneaded in one or both layers of the resin or coated on the surface.

The moisture-proof performance of the composite sheet must be at least 1.5 g / m ² · 24 hr or less, more preferably 0.6 g / m ² , measured by JIS Z 0208 at 40 ° C. and 90% RH. m ² · 24 hr or less is good. If it exceeds 1.5 g / m ² · 24 hr, the function of preventing cracks in the sealing resin at the time of solder mounting is insufficient, and protection and storage by packaging in a moisture-proof bag in a later process, or implementation of rebaking is required. Required. When the embossing is performed, the layer on the side of the carrier tape that is sealed with the cover tape may be either the first layer 2 or the second layer 3, but in order to further stabilize the sealing property with the cover tape. It is preferable that the first layer 2 be a surface sealed by a cover tape of a carrier tape. Further, the layer constituting the carrier tape may be a composite film of three or more layers having the above two layers as a basic unit.

[0007]

EXAMPLES Examples of the present invention are shown below, but the present invention is not limited by these examples. << Examples 1, 2, 3, 4, 5, 7, 8, 9 and Comparative Examples A, B, C, D >> A first layer made of a thermoplastic resin having excellent embossability and having a thickness of 200 μm, and A second layer of a 10 μm thick metal layer made of a metal foil having excellent moisture resistance is bonded by dry lamination with a two-component thermosetting type urethane-based adhesive to form a two-layer composite sheet for a carrier tape having a total thickness of 210 μm. Obtained. The obtained composite sheet was embossed with a layer having a moisture-proof function outside the emboss by a pressure molding machine to obtain a carrier tape having a width of 24 mm.
Also, the moisture permeability of the composite sheet is determined according to JIS Z 0208 method 40.
C., 90% RH. Next, the electronic component QFP
The 52P was housed in an emboss and sealed with a cover tape using PET for the biaxially oriented film of the outer layer 5 and a sealant layer 7 using an acrylic adhesive in the layer configuration shown in FIG. After the sample was placed in a 30 ° C., 70% RH environment for 60 days, the cover tape was peeled off, and the change in weight of the sealing resin of the electronic component due to moisture absorption was measured to calculate the moisture absorption rate. Next, the removed electronic component is subjected to IR reflow (240 ° C., 1
0 second) and observed for cracks with an engineering microscope (× 100).
It was shown to.

Table 1

Note 1: The raw material names of the resins used are as follows. PVC: VSS-1 manufactured by Sumitomo Bakelite Co., Ltd.
202 PS: Toporex PC manufactured by Mitsui Toatsu Chemicals Co., Ltd. Lexan PP manufactured by GE Co., Ltd. Noblen PAN manufactured by Sumitomo Chemical Co., Ltd. PAN: Zeklon Urethane manufactured by Mitsui Toatsu Chemicals, Inc .: Kyowa Hakko Kogyo Ltd. Estan ABS: Sumitomo Nogatack Co., Ltd. Plastics PET: Eastman Chemical Co., Ltd. PE
TG (Amorphous) Note 2: The moisture permeability is JIS Z in the state of the composite sheet before molding.
The measurement was performed at 40 ° C. and 90% RH. Note 3: Moisture absorption after sealing in carrier tape, 30 ℃, 7
0% RH, QFP in carrier tape treated for 60 days
Calculated from the weight change of 52P (14 mm x 14 mm x 2 mmt). Note 4: Cracks were evaluated by soldering electronic components taken out of the carrier tape and observing the surface of the sealing resin.

[0010]

According to the present invention, the electronic components housed in the carrier tape do not absorb moisture during transportation and storage of the electronic components without being repackaged by a dry pack in a later process, and can be used during the mounting process. There is no need for re-baking, and the occurrence of cracks in the sealing resin in the soldering process can be prevented. At the same time, the dry pack packaging step and the re-baking step can be omitted, and the number of steps can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a layer configuration of a carrier tape of the present invention.

FIG. 2 is a cross-sectional view showing an example of a layer configuration of a cover tape to be sealed on the carrier tape of the present invention.

Claims (2)

(57) [Claims] 1. A plastic embossed tape in which storage pockets for accommodating chip-type electronic components are continuously formed, wherein at least one layer is a thermoplastic resin which can be embossed, and at least the other layer is Al, Cu, Z
A composite sheet of two or more layers composed of a metal layer made of any one of n, Sn, Ni, Ti or a compound thereof, wherein the moisture permeability of the composite sheet is JIS Z 0208 40 ° C., 90%
A carrier tape for packaging chip-type electronic components, which has an RH measurement method of 1.5 g / m ² · 24 hr or less. 2. The chip-type electronic component packaging according to claim 1, wherein the embossable thermoplastic resin is any of amorphous polyester, polyurethane, polypropylene, polystyrene, polycarbonate, ABS, polyacrylonitrile, and polyvinyl chloride. Carrier tape.