JPH08298298A - Semiconductor carrier - Google Patents

Abstract

PURPOSE: To obtain a semiconductor carrier and a plastic semiconductor package having an excellent heat resistance, moisture resistance, insulating ability, low dielectric constant, and chemical resistance by using an electric insulating layer which is made by impregnating total aromatic liquid crystal polyester nonwoven fabric with cyanate resin component and then hardening it. CONSTITUTION: A conductor circuit is formed on a copper lined laminated sheet; a semiconductor chip 3 is placed on one surface; solder balls are provided at pad portions made of poreless copper foil on the opposite surface; and the terminal of semiconductor chip 3 and a pad copper foil 5 are brought into a continuity. Moreover, the conductor circuit and copper foil 5 are bonded to an electric insulating layer which was produced by impregnating a total aromatic liquid crystal polyester unwoven cloth with a cyanate resin component and then hardening, thereby forming a semiconductor carrier. By doing this, subminiature radius hole machining by laser beam can be performed in an outermost electric insulating layer, from which a semiconductor carrier and a plastic semiconductor package, which can be highly densified, can be produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor carrier having a high heat resistance, a high insulation property, a high humidity resistance and a low dielectric constant and a plastic semiconductor package.

The electric insulating layer of a copper clad laminate used for semiconductor carriers and plastic semiconductor packages is a glass cloth impregnated with a thermosetting resin and cured,
Aramid fiber impregnated with thermosetting resin and cured,
Examples include those using a polyimide resin.

A glass cloth impregnated with a thermosetting resin and hardened is generally used, but a drill is generally used to form a through hole for connecting to a conductor circuit. However, there is a limit to the drilling of ultra-small diameters, and there is a limit to increasing the density of semiconductor carriers and plastic semiconductor packages.

A aramid fiber impregnated with a thermosetting resin and cured has poor moisture resistance and lowers reliability.

A cured product of a polyimide resin is inferior in heat resistance and moisture resistance and lowers reliability. The electrical insulating layer exemplified above results in extremely poor reliability as a semiconductor carrier and a plastic semiconductor package.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a highly reliable, high-density semiconductor carrier and a plastic semiconductor package which solves the above-mentioned drawbacks of the conventional semiconductor carrier and plastic semiconductor package material.

[0007]

Means for Solving the Problems That is, according to the present invention, a wholly aromatic liquid crystal polyester non-woven fabric is impregnated with a cyanate resin composition, and an electrically insulating layer obtained by curing is used to obtain a
A semiconductor carrier and a plastic semiconductor package with excellent moisture resistance, insulation, low dielectric constant, and chemical resistance can be obtained, and in addition, through holes and / or blind through holes can be formed by laser irradiation. The problem can be solved by forming ultra-small diameter holes with high density.

The thermosetting resin in the present invention means a cyanate resin in an amount of 30 wt% or more of the whole resin, and also polyvalent maleimide, epoxy resin, unsaturated polyester resin, phenol resin, diallyl phthalate resin, polyamine-bismaleimide. Resins, polymaleimide-isocyanate resins, other thermosetting resins; thermoplastic resins such as polyvinyl butyral, acrylonitrile-butadiene rubber, polyfunctional acrylate compounds, polyphenylene ether, etc., containing a composition prepared by appropriately mixing two or more of these. , Other known resins, and those modified with additives are exemplified.

The liquid crystal polyester non-woven fabric is a non-woven fabric using a liquid crystal polyester fiber obtained by spinning a liquid crystal polyester resin. Further, the liquid crystal polyester resin is a polymer capable of forming an anisotropic molten phase. The liquid crystal polyester fiber is not particularly limited, but a fiber made of wholly aromatic polyester (that is, polyester whose main chain is composed of repeating units of aromatic rings) resin is preferable. Therefore,
A resin obtained by appropriately combining an aromatic diol, an aromatic dicarboxylic acid, and / or an aromatic hydroxycarboxylic acid. Among these, the polyester copolymer of p-hydroxybenzoic acid and 2-hydroxynaphthalene-6-carboxylic acid has excellent balance of spinnability and heat resistance, and therefore can be preferably used, and p-hydroxy Because the polyester copolymer of benzoic acid, terephthalic acid, and 4,4′-hydroxyphenyl has excellent heat resistance,
It can be preferably used. Further, the above liquid crystal polyester non-woven fabric, plasma-treated or calendered,
Sequins may be used as appropriate.

The liquid crystal polyester nonwoven fabric may be impregnated with a solution of the above-mentioned thermosetting resin composition or a liquid solventless one by a known method and dried. The amount of resin at this time is 40 to 70
The wt% and the molding thickness are preferably 0.03 to 0.25 mm.

For the laser-drilling, a carbon dioxide gas laser or an excimer laser can be used as the laser, but a carbon dioxide gas laser is preferred. The carbon dioxide gas laser irradiation conditions represent the irradiation fluence (energy density) of the laser light, and the M value (reduction ratio) is 5 to 20, preferably,
8-14. The number of pulses is uniquely determined by the thickness of the electrical insulating layer to be removed and the irradiation fluence.

According to the present invention, since the outermost electric insulating layer can be drilled with a laser beam having a very small diameter, blind via holes can be arranged at a high density, and high heat resistance, high humidity resistance, high insulation property, low dielectric constant, A plastic semiconductor package having excellent chemical resistance is provided. In addition, it is possible to form a through hole by drilling a hole, if necessary.

[0013]

EXAMPLES The concrete contents of the present invention will be described below.
They do not limit the scope of the invention. The "parts" in the examples are by weight unless otherwise specified. Example 1 As a thermosetting resin, 540 parts of 2,2-bis (4-cyanatephenyl) propane and 60 parts of bis (4-maleimidophenyl) methane were pre-reacted at 150 ° C. for 130 minutes, and this was reacted with methyl ethyl ketone and N 2. , N-dimethylformamide was dissolved in a mixed solvent. Bisphenol A
A varnish was obtained by dissolving 600 parts of a type epoxy resin (trade name; Epicoat 1001, manufactured by Yuka Shell Epoxy Co., Ltd., epoxy equivalent: 450 to 500) and 0.1 part of zinc octylate.

Liquid crystal polyester non-woven fabric with a thickness of 0.1 mm (p
-Hydroxybenzoic acid and 2-hydroxynaphthalene-6
-Comprising carboxylic acid) was impregnated with the above varnish and dried to obtain a prepreg. 18 on both sides of the prepreg obtained above
Pressure of 20kgf / cm ² ,
Insulation layer thickness 0.
A 1 mm double-sided copper clad laminate was obtained.

On one side of the obtained double-sided copper-clad laminate, the copper foil at the position for laser ultra-small diameter (100 μm) drilling was removed.
The unpenetrated holes were processed using a carbon dioxide laser. The obtained copper-clad laminate was plated to conduct electricity on the front and back sides, and then a conductor circuit and pads for solder balls were formed into printed boards. Epoxy Ag paste (Ab
Silicon chip (10mm) using lestick 965-1L
After bonding 10 mm), the semiconductor terminal and the circuit conductor were connected by gold wire wire bonding and sealed with an epoxy-based encapsulation compound to produce a pseudo package. After the moisture absorption treatment of the pseudo package at 40 ° C, 85% RH for 48 hours, 260 ° C,
Immersed in solder for 5 seconds.

Example 2 The same procedure as in Example 1 was carried out except that a 4-layer copper clad laminate was used and carbon dioxide gas lasers were used on both sides of the outermost electrical insulating layer to form unpenetrated holes.

Comparative Example 1 The same procedure as in Example 1 was carried out except that aramid fiber (trade name: Technora; manufactured by Teijin Ltd.) was used.

Comparative Example 2 The same procedure as in Example 2 was carried out except that aramid fiber (trade name: Technora; manufactured by Teijin Ltd.) was used. The above results are shown in Table 1.

[0019]

Table 1 Types of base materials used during heat shock Number of cracks / number of tests Example 1 Liquid crystal polyester non-woven fabric 0/10 Example 2 Same as above 0/10 Comparative example 1 Aramid fiber 8/10 Comparative example 2 Same as above 8/10

[0020]

As is apparent from the detailed description of the invention, Examples and Comparative Examples, according to the semiconductor carrier and the plastic semiconductor package of the present invention, the wholly aromatic liquid crystal polyester nonwoven fabric is provided with the cyanate resin composition. By using the impregnated and hardened electrical insulation layer, it has excellent heat resistance, moisture resistance, insulation, low dielectric constant and chemical resistance, and the outermost electrical insulation layer can be processed with ultra-small diameter holes by laser light, resulting in high density. It is possible to manufacture a semiconductor carrier and a plastic semiconductor package that can be realized, and the significance thereof is extremely high.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a semiconductor carrier of the present invention.

FIG. 2 is a schematic diagram showing a state where FIG. 1 is viewed from above.

FIG. 3 is a schematic diagram showing a state where FIG. 1 is viewed from the lower side.

FIG. 4 is a sectional view schematically showing a three-layer copper-clad laminate semiconductor carrier of the present invention.

FIG. 5 is a schematic diagram showing a state of FIG. 4 viewed from the upper side (first layer).

FIG. 6 is a schematic view showing a second layer of FIG.

FIG. 7 is a schematic diagram showing a state where FIG. 4 is viewed from the lower side (third layer).

[Explanation of symbols]

 1 Sealing compound 2 Wire 3 Silicon chip 4 Through hole 5 Solder ball pad 6 Solder ball 7 Blind via hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Morio Gaku 2-5-2 Marunouchi, Chiyoda-ku, Tokyo Sanryo Gas Chemical Co., Ltd.

Claims (3)

[Claims] 1. A semiconductor chip terminal comprising a conductor circuit formed on a copper clad laminate, a semiconductor chip mounted on one surface, and a solder ball provided on a pad portion made of copper foil having no holes on the opposite surface. A semiconductor carrier in which the pad copper foil and the copper foil are electrically connected to each other, wherein the conductor circuit and the copper foil impregnate a wholly aromatic liquid crystal polyester nonwoven fabric with a thermosetting resin of a cyanate resin composition, and adhere the cured electrical insulating layer. A semiconductor carrier. 2. The copper-clad laminate according to claim 1, wherein the copper-clad laminate has three or more layers, and at least one outermost layer of the multilayer copper-clad laminate is a wholly aromatic liquid crystal polyester non-woven fabric and a cyanate resin composition. A plastic semiconductor carrier having an electric insulating layer which is impregnated with and cured by the thermosetting resin. 3. The small-diameter hole formed by removing the outermost electrical insulation layer with a laser beam in claim 1, is connected to a conductor circuit formed on the surface opposite to the electrical insulation layer by copper plating. Semiconductor carrier to do.