JP2969490B2 - Carbon jig for EPROM package manufacturing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carbon jig for manufacturing an EPROM package, and more particularly to a carbon jig used for fusing and fixing an ultraviolet ray introducing glass to an EPROM ceramic package.

[0002]

2. Description of the Related Art An EPROM is a type of ROM having the characteristic that all stored information can be erased by irradiating ultraviolet rays from a glass window attached to the top surface of a package, and is widely used as a component of various electronic devices. ing. In this device, in addition to the IC chip, a glass window plays an important role. For example, if the glass becomes opaque or the glass surface becomes dirty, the effect of ultraviolet irradiation cannot be obtained.

FIG. 1 (plan view) shows an EPROM package.
As shown in FIG. 2 (cross-sectional view), a glass disk 2 is fixed to a center hole of a ceramic plate 1 to form a window. Conventionally, a glass window is fixed to a ceramic plate. The following process is adopted. That is,
As shown in FIG. 3, the EPROM is placed on the carbon jig 3 underneath.
A ceramic plate 1 having a center hole serving as a frame of a package is placed, and a glass disk 2 is fitted into the center hole. After the upper carbon jig 4 having an opening having the same size as the center hole of the ceramic plate 1 is stacked on the upper part thereof, the weight carbon jig 5 is fitted into the opening. Heat treatment in an inert gas atmosphere such as nitrogen or argon in such a set state,
The glass disk 2 is melted and fused to the ceramic plate 1 to be fixed as a glass window.

[0004] For each carbon jig used in the above process, a graphite material, which is a heat-resistant material having good workability, was initially useful. Was detached and stained the glass window, and scratches and the like generated on the surface of the jig were transferred to the glass surface as it was, resulting in impaired transparency and smoothness. In order to solve such a problem, an EPR in which the carbon material is made of a hard and substantially gas-impermeable glassy carbon.
An OM package manufacturing jig has been developed and put to practical use (Japanese Patent Publication No. 3-42509).

[0005]

The jig made of the vitreous carbon material does not cause the phenomenon that the glass is stained by the generation of powder or the surface of the jig is damaged. Stable use is possible. However, since the jig material is too dense and has gas impermeability, outgassing at the time of glass fusion becomes incomplete, and there is a problem that the transparency of the glass is sometimes reduced. In addition, processing into a jig shape was extremely difficult due to high hardness.

[0006] An object of the present invention is to select a glassy carbon material having appropriate air permeability and not extremely hard for a tissue as a jig material, thereby reducing the risk of a decrease in glass transparency due to insufficient gas release during package formation. An object of the present invention is to provide a carbon jig for manufacturing an EPROM package which is free from troubles such as powder detachment and flaw formation.

[0007]

In order to achieve the above object, a carbon jig for producing an EPROM package according to the present invention has an average pore diameter of 20 μm or less and a gas permeation amount of 0.01 to 20 ml.
A structural feature is that it is made of a vitreous carbon material having characteristics of /hr.cm.mmAq and a Shore hardness of 30 to 110. The gas permeation amount refers to a permeated gas amount when nitrogen gas is permeated through a glassy carbon specimen having a diameter of 50 mm and a thickness of 3 mm at room temperature under a pressure of 200 mmAq.

The glassy carbon material forming the jig of the present invention is characterized by a material structure having a moderate air permeability in which fine pores are uniformly distributed and a hardness structure not extremely high, and is specified by the above structure. The intended purpose is effectively achieved when the average pore diameter, the amount of gas permeation and the hardness are satisfied.

That is, the characteristic range of the average pore diameter of 20 μm and the gas permeation amount of 0.01 to 20 ml / hr.cm.mmAq, which indicates that the glassy carbon structure has an appropriate air permeability, facilitates the degassing during melting of the glass. This is an important requirement for fusing and fixing transparent glass without product trouble. If the size of the intervening average pore diameter exceeds 20 μm, fine irregularities appear on the surface, resulting in a decrease in the surface smoothness of the glass. On the other hand, if the gas permeation amount is less than 0.01 ml / hr.cm.mmAq, the outgassing becomes insufficient and the transparency of the fused glass is impaired, while the gas permeation amount exceeds 20 ml / hr.cm.mmAq. Then, oxidation consumption based on the residual oxygen proceeds in the use stage, and the use life of the jig is greatly reduced.

[0010] The material hardness is also important.
It is a requirement that it be within the range of ~ 110. Shore hardness
If it is less than 30, particles are detached due to structural deterioration during use and the transparency of the glass is impaired. If it exceeds 110, material processing becomes extremely difficult.

It is difficult to obtain a glassy carbon material having the above-mentioned structural characteristics by a method of carbonizing a molded article of a thermosetting resin, which has conventionally been a typical production means. However, when a method of carbonizing a molded article obtained by impregnating a thermosetting resin liquid into a cellulose fiber at a temperature range of 1000 to 2700 ° C. is applied, a glassy carbon material satisfying the characteristic range of the present invention can be easily produced. be able to.

The preferred process for producing a vitreous carbon material by this method is specifically described as follows. First, short fibers (thickness: 3 to 10 denier, length: 5 to 10 mm) containing 90% or more of α-cellulose such as pulp or rayon pulp are dispersed in water together with a binder component such as polyvinyl alcohol, and formed into a papermaking sheet. . After being dried, the papermaking sheet is immersed in a thermosetting resin solution having a residual carbon ratio of 40% or more to be impregnated and semi-cured. Residual carbon ratio of thermosetting resin is 800 in non-oxidizing atmosphere.
Refers to the weight of carbon remaining when fired at a temperature of ℃.
Examples of such resins containing a residual carbon ratio of 40% or more include phenol resins, furan resins, and polyimide resins. The organic solvent used for forming the thermosetting resin into a solution is selected according to the type of the resin. Usually, an organic solvent such as methanol, ethanol, acetone, or methyl ethyl ketone, which has a low viscosity, high permeability, and easily volatilizes by heat, is used. Selected from solvents.

Then, a required number of semi-cured sheets are laminated, and the entire surface is uniformly compressed to form a laminate. Subsequently, the molded body is fired in a non-oxidizing atmosphere at a temperature in the range of 1000 to 2700 ° C. to evaporate the heat-volatile component and to carbonize the thermosetting resin component to convert it into a glassy carbon material.
It is important to set the temperature range during this carbonization process.
If the temperature is lower than ℃, the material is easily oxidized, and 2700 ℃
When the temperature exceeds the limit, graphitization proceeds, and detachment of fine particles occurs.

By appropriately adjusting the papermaking conditions of the cellulose fiber raw material, the amount of the impregnated resin, the conditions of the lamination molding, and the like, using the above-mentioned production process, the average pore diameter is 20 μm or less, and the gas permeability is 0.01 to 20 ml / hr. .mmAq texture and Shore hardness
A glassy carbon material having a material characteristic of 30 to 110 can be produced. The carbon jig for manufacturing an EPROM package of the present invention is manufactured by processing the glassy carbon material.

[0015]

The carbon jig for manufacturing an EPROM package according to the present invention has an average pore diameter of 20 μm or less and a gas permeability of 0.01 to 2 μm.
It has a moderate air permeability of 0ml / hr.cm.mmAq, which is effective for smooth outgassing at the time of fusing glass and maintaining normal transparency of the glass at all times. Perform a typical action. In addition, the porous structure is not so large as to cause irregularities on the surface of the material, so that glass molding with excellent surface smoothness can be performed, and even in long-term use, oxidative consumption that causes practical problems will occur. Never.

Since the material hardness is in the range of 30 to 110 as the Shore hardness, relatively good material workability can be secured, and the other material structure is excellent in a skeletal structure which does not have powder detachment inherent to glassy carbon. Because of the excellent surface lubricity and mechanical strength, it is possible to efficiently manufacture an EPROM package without any operational trouble.

[0017]

Examples 1 to 8 and Comparative Examples 1 to 5 Cellulose fibers containing 90% of α-cellulose were prepared by a papermaking method using polyvinyl alcohol as a binder.
The sheet was formed into a sheet having a thickness of 00 mm and a thickness of 0.1 mm.
0 "], dried and then laminated the same
The molded body was obtained by hot pressing under heating at a temperature of ° C. Next, the compact was placed in an electric furnace, and the surroundings were covered with coke powder for 15 minutes.
The carbonization treatment was performed by raising the temperature to a temperature of 1000 to 2700 ° C. at a rate of ° C./hr. At this time, by controlling the papermaking conditions, the amount of the impregnated resin, the molding pressure and the carbonization temperature, glassy carbon materials having different average pore diameters, gas permeation amounts, Shore hardness and the like were produced.

Each of the obtained glassy carbon materials was processed into a jig shape, and transferred to a 900 ° C. electric furnace held in a nitrogen atmosphere in a set form as shown in FIG. 3 to conduct a production test of an EPROM package. Product yield of each jig (50 pieces manufactured)
Table 1 shows the product appearance, oxidation loss and the like in comparison with the material properties. As Reference Example 1, a dense graphite material [“G347” manufactured by Tokai Carbon Co., Ltd.], and as Reference Example 2, a substantially gas-impermeable glassy carbon material produced by carbonizing a phenolic resin molded article [Tokai Carbon "GC2" manufactured by
0 ″] was also tested similarly.
The results are shown in Table 1. In addition, the oxidation weight loss is 100
It is shown by the degree of thickness reduction (mm) after repeated use.

[0019]

[Table 1]

From the results shown in Table 1, the use of the carbon jig of the present invention makes it possible to mount the glass window for ultraviolet irradiation of the EPROM package with good glass transparency while maintaining good glass transparency. Moreover, the workability of the jig is good and the service life is long.

[0021]

As described above, according to the present invention, by selecting and using a glassy carbon material having a structure having an appropriate air permeability and a hardness not extremely high as a jig material, a transparent material always having good transparency can be obtained. It is possible to efficiently manufacture an EPROM package in which a glass window is fixed. Therefore, the productivity of the EPROM package can be improved as compared with a conventional carbon jig made of a graphite material or a glassy carbon material having a dense structure.

[Brief description of the drawings]

FIG. 1 is a plan view showing an EPROM package.

FIG. 2 is a sectional view showing an EPROM package.

FIG. 3 is a cross-sectional view showing a set state of a carbon jig when an EPROM package is manufactured.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ceramic plate 2 Glass disk 3 Underlay carbon jig 4 Upper carbon jig 5 Weight jig for weight

Claims (2)

(57) [Claims] 1. An average pore diameter of 20 μm or less and a gas permeation amount of 0.01
A carbon jig for manufacturing an EPROM package, comprising a glassy carbon material having characteristics of about 20 ml / hr.cm.mmAq and a Shore hardness of 30 to 110. 2. The EPROM package according to claim 1, wherein the glassy carbon material is obtained by carbonizing a molded article obtained by impregnating a cellulose fiber with a thermosetting resin liquid at a temperature in the range of 1000 to 2700 ° C. Carbon jig for manufacturing.