JP3968381B2 - How to open the resin - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for opening a resin sealing a circuit component. Specifically, the present invention relates to a method for opening a resin that does not require the use of chemicals that require post-treatment such as fuming nitric acid and concentrated sulfuric acid.
[0002]
[Prior art]
Conventionally, for example, in order to analyze a failure of a semiconductor device, an integrated circuit chip sealed inside the device is observed using an optical microscope or an electron microscope. As shown in FIG. 3, so-called unsealing is performed to remove a part of the package resin above the integrated circuit chip in order to analyze an LSI that does not perform or to modify the processing depending on the case.
[0003]
As shown in FIG. 4, the conventional method for opening a resin is to form a recess in a part of the resin above the circuit component using, for example, a grinder, and apply a powerful drug such as fuming nitric acid or concentrated sulfuric acid to the recess. This is an unsealing method in which the desired part of the substrate is melted and removed to expose the surface of the circuit component.
[0004]
Problem of dimensional accuracy in melting and removing means of desired resin portion by vigorous drug such as fuming nitric acid or concentrated sulfuric acid, that is, lead frame in which size of resin removing portion exceeds, for example, IC chip outer dimensions and is embedded in surrounding package resin Japanese Laid-Open Patent Publication No. 2001-358158, for example, discloses a technique that solves the problem of peeling the bonding wire connected to the lead frame and pulling the bonding wire to break. However, even in this prior art, there is no difference from the prior art in that fuming nitric acid is used as the resin opening means.
[0005]
[Problems to be solved by the invention]
When using the above prior art, it is necessary to set up a special working environment to safely use powerful fumes such as fuming nitric acid and concentrated sulfuric acid used to open the resin, and a process to make these harmful powerful poisons harmless. Become. In addition, the resin opening operation accompanied with handling of powerful drugs such as fuming nitric acid and concentrated sulfuric acid has a problem of lack of precision. This problem has become more serious under the trend that circuit components such as LSI are becoming finer and more complicated.
[0006]
On the other hand, for example, the manufacturing process of circuit components such as LSIs has been integrated into a series of processes from design to testing, and the commercialization of independent circuit component design processes has progressed. It has become a form to perform in the place. Thus, there is an increasing need to make it possible to easily and quickly perform analysis and processing correction work of circuit parts deeply related to circuit part design work in the normal office.
[0007]
As mentioned earlier, in order to analyze and correct circuit components, it is necessary to open the resin that seals the circuit components. This opening is performed in a normal office where circuit components are designed. Therefore, there has been a strong demand for technical means that can be performed without using a means that requires detoxification treatment even after opening using powerful drugs such as fuming nitric acid or concentrated sulfuric acid. It is desirable that the material used for opening can be reused and recycled. Furthermore, it is necessary to be means that can easily control the position and size of the resin opening portion.
[0008]
The present invention does not use a powerful medicine such as fuming nitric acid or concentrated sulfuric acid to open the resin, and does not require any detoxification treatment after opening, and the position and size of the resin opening can be controlled with high accuracy. An object of the present invention is to provide a method for opening a resin in which the material used can be reused and recycled.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a melt of a substance in a glass state is dropped on a portion where the resin of a circuit component sealed with resin is opened and the circuit component is to be exposed. This is a method of opening a resin in which the resin is heated in a shut-off state to change and soften a desired portion of the resin, and then mechanically processed to open the resin. According to the present invention, without using a powerful drug that requires detoxification after opening, such as fuming nitric acid or concentrated sulfuric acid, and the resin portion to be opened is heated in an oxygen-blocked state, The resin can be opened without causing combustion. Further, a melt of a substance in a glass state used for opening becomes a glassy solid at room temperature, and this can be reused and recycled.
[0010]
The invention according to claim 2 is a substance in a glass state corresponding to one or both of the area and the depth of the portion where the resin of the circuit component sealed with resin is opened and the circuit component is to be exposed. The method for opening a resin according to claim 1, wherein control is performed to change either or both of the temperature and amount of the melt. According to the present invention, the position and size of the resin opening part can be controlled with high accuracy.
[ 0011 ]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described according to preferred embodiments thereof.
The present invention is a resin opening method, for example, a substance in a glass state such as a waste glass bottle, glass cullet, water glass, silica glass, silicate glass, borate glass, phosphate glass, vanadate glass, etc. Alternatively, these mixtures are heated to form a melt, which is dropped onto a desired portion of the resin that seals the circuit components to alter and soften the resin to facilitate mechanical processing. For example, with a grinder The altered and softened parts are removed by grinding and easily opened. At that time, the size (area / depth) of the part to be opened can be controlled with high accuracy by controlling the temperature and / or the amount of the melted substance or the mixture in the glass state to be dropped. . In addition, the melted substance in a glassy state or a mixture thereof can be easily recovered as a glassy solid at room temperature, and can be reused and recycled, and is non-polluting.
[ 0012 ]
In the present invention, as shown in FIG. 1, the portion 3 to be opened of the resin 2 that seals the circuit components by the heat of the melt 1 of the substance in the glass state is in a high temperature state under the interruption of oxygen. The heat is transmitted exclusively in the direction perpendicular to the surface of the resin 2 without causing smoke or combustion, and the resin 2 is altered only at the heat receiving part, and its physical properties are changed to allow simple mechanical processing such as grinding. Easily deleted by ding.
[ 0013 ]
In the present invention, the substance in a glass state used as a means for applying heat to the portion 3 to be opened of the resin 2 under oxygen interruption is silicon, boron, phosphorus, vanadium, aluminum, iron, gallium, tellurium, etc. Any of oxides and carbonates or mixtures thereof, as well as oxides or carbonates of alkali metals or alkaline earth metals such as lithium, sodium, potassium, calcium, magnesium, strontium, barium, or mixtures thereof It may be a compound.
[ 0014 ]
Although the preferred embodiment of the present invention has been described above, the inventors have made various studies on means for opening a desired portion of a resin sealing a circuit component without using a powerful drug such as fuming nitric acid or concentrated sulfuric acid. As a result, the region to be opened of thermosetting resin such as phenol resin, urea resin, melamine resin, and unsaturated polyester resin, which is a resin that seals circuit components, is heated to a temperature range of 800 ° C. to 1000 ° C. It is thought that the carbon-carbon bond of the resin can be broken to alter and soften the resin, and the resin in the glass state is heated to form a high-temperature melt, and this is dropped onto the portion of the resin to be opened. The resin was transformed and softened, and the resin was successfully opened by simple mechanical processing such as grinding. The present invention has been completed by this finding by the inventors. At that time, it is necessary that the resin does not generate smoke and combustion, and for this purpose, heating and temperature rise must be performed while blocking oxygen to the resin.
[ 0015 ]
The inventors of the present invention do not provide large-scale equipment such as electric equipment for heating or a temperature control device, and heat a material in a glass state suitable for the heating conditions as a material that is easy to handle, easy to reuse, and recycle. Selected as medium.
[ 0016 ]
Of course, the present invention, the heating of the resin by substances in the glass state, not limited to heating, other heating, heating of the resin due to temperature increase device such as high temperature metals, heating by heating and highly integrated energy beam such as a laser It may be.
[ 0017 ]
【Example】
Example 1
A melt mainly composed of vanadium pentoxide heated and melted at 800 ° C. is dropped onto the portion 3 of the package resin 2 to be opened, and when the surface becomes soft, it is manually opened using tweezers. Tried. This was performed 5 times, but it took about an hour to open the material, although it became easier to cut. Next, a melt mainly composed of vanadium pentoxide heated and melted at 1000 ° C. was dropped onto the portion 3 of the package resin 2 to be opened, and was manually opened using tweezers. When the vanadium pentoxide melt temperature was 1000 ° C., the viscosity of the melt was too low and the melt spread on the surface of the package resin 2. In this case, it is difficult to heat a narrow and limited region, but if the enclosure is made so that the melt does not flow out, the package resin 2 can be opened at the melt temperature.
[ 0018 ]
Example 2
A waste glass bottle (silicate glass) [cola bottle] was used. This silicate glass has a high melting point , and the melt heated and melted at 1000 ° C. has a high viscosity and is difficult to be dropped onto the portion 3 of the package resin 2 to be opened. Therefore, in order to lower the melting point, the waste glass added with boron oxide, sodium carbonate, and calcium carbonate was heated and melted. The composition is waste glass: boron oxide: sodium carbonate: calcium carbonate = 3: 1: 1: 1. The glass melt (1000 ° C.) was dropped onto the portion 3 of the package resin 2 to be opened to soften the surface, and then the resin was removed with tweezers. As a result of performing the same operation four times, opening was possible, but it took about 30 minutes. In order to remove in a short time, the glass was dropped and then ground with a grinder instead of tweezers, it was easy to open. The required time was about 1 to 2 minutes.
[ 0019 ]
Example 3
Water glass was used. Since water glass is a liquid having a high viscosity at room temperature, if water glass is used, it is possible to position the water glass at a portion 3 to be opened of the package resin 2 and to heat only the water glass with a laser or the like in that state. it can. After holding the water glass melt at 1000 ° C. in the portion 3 of the package resin 2 to be opened, it was easily opened by grinding with a grinder. The required time was about 1 to 2 minutes.
[ 0020 ]
Example 4
Water glass + vanadium pentoxide (1: 1) was used. The glass glass + vanadium pentoxide (1: 1) melt at 1000 ° C. was dropped onto the portion 3 of the package resin 2 to be opened, and then ground with a grinder, so that it could be easily opened. The required time was about 1 to 2 minutes.
[ 0021 ]
In the above embodiment, the dimension (area, depth) of the portion 3 of the package resin 2 to be opened is controlled by controlling either or both of the temperature and amount of the melt of the substance in the glass state. Can be opened with high accuracy.
[ 0022 ]
Reference Example FIG. 2 shows an apparatus for carrying out the resin opening method of the present invention. In FIG. 2, 11 is a means for heating and melting a substance in a glass state, and functions to make the substance in a glass state a melt thereof. As the heating and melting means 11 for the substance in the glass state, an electric furnace, burner, microwave oven, laser or the like can be used. The heating and melting means 11 for the substance in the glass state is equipped with a temperature control mechanism. Reference numeral 12 denotes melt droplet dropping means for dropping a melt of a substance in a glass state onto a desired region of the portion 3 of the package resin 2 to be opened. 13 is a mechanical processing means, for example, a grinder is used. The mechanical processing means 13 removes and opens the resin of the portion 3 to be opened of the package resin 2 that has been altered or softened by dripping and heating the melt of a substance in a glass state.
[ 0023 ]
The resin opening method of the present invention is not limited to the LSI field, but is applied to the fields of thin film magnetic heads, display devices (liquid crystal devices, plasma display devices, etc.), printed circuit boards, and CCDs (charge coupled devices). be able to.
[ 0024 ]
Although the present invention has been described with reference to the above-described preferred embodiments, the present invention is not limited to this, and the present invention is not limited to this, and is applied exclusively by applying heat to a desired portion of the resin under a condition that does not cause the resin to smoke or burn. A method may be employed in which heat is transmitted in a direction perpendicular to the surface of the resin, and a desired portion of the resin is locally heated to be altered and softened, and then subjected to mechanical processing for opening.
[ 0025 ]
As a means of applying heat to a desired part of the resin under a state in which the smoke and combustion of the resin are suppressed, for example, a metal rod heated to a high temperature by energization or the like in an inert gas atmosphere such as nitrogen gas is pressed. It is possible to take means for heating. Also, a means for irradiating a highly integrated energy beam such as a laser can be employed.
[ 0026 ]
【The invention's effect】
According to the present invention, it is possible to open a desired portion of a resin sealing a circuit component without using a powerful drug such as fuming nitric acid or concentrated sulfuric acid.
[ 0027 ]
According to the second aspect of the present invention, the resin that seals the circuit components can be opened easily and accurately in a very short time without using a powerful drug such as fuming nitric acid or concentrated sulfuric acid. Therefore, it is not necessary to perform analysis and modification of the circuit components after designing the circuit components under a special environment corresponding to the use of powerful drugs such as fuming nitric acid or concentrated sulfuric acid, and can be performed in a general office. Thus, in the field of packaged printed circuit boards mounted on devices and the like, it is possible to add a correction process after manufacturing according to the present invention even in regions where it has been difficult to introduce “correction work”. Can create a new process and can bring about a major change in the production line.
[ 0028 ]
Further, a melt of a substance in a glass state dripped onto a resin sealing a circuit component can be easily recovered as a glassy solid at room temperature, and can be reused and recycled any number of times. Furthermore, it is possible to perform control corresponding to the dimensions (area and depth) of the part to be opened of the resin sealing the circuit component. Further, the resin can be opened with high productivity with a simple apparatus configuration.
[ 0029 ]
[Brief description of the drawings]
FIG. 1 is a schematic view showing an embodiment of a resin opening method according to an embodiment of the present invention. FIG. 2 is a schematic view showing an embodiment of a resin opening device of the present invention. FIG. 4 is a schematic view showing a conventional method for opening a semiconductor device package resin. [ 0030 ] FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Melt of substance in glass state 2 Resin 3 Part to be opened of resin sealing circuit component 11 Heating and melting means 12 of glassy substance 12 Melting liquid dropping means 13 Mechanical processing means

Claims (2)

  The resin part of the resin-sealed circuit component is opened and the circuit part is exposed, and a melt of a substance in a glass state is dropped and the resin is heated in an oxygen-blocked state to change the desired part of the resin, A method of opening a resin, characterized in that after being softened, the resin is opened by mechanical processing.   The temperature and amount of the melt of the substance in the glass state corresponding to one or both of the area and the depth of the portion where the circuit component should be exposed by opening the resin of the resin-sealed circuit component The method for opening a resin according to claim 1, wherein control is performed to change one or both of them.

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