JP3427713B2 - Resin-sealed semiconductor device and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-sealed semiconductor device including a semiconductor element having a ferroelectric film and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, a non-volatile or large-capacity semiconductor memory device having a thin film of a ferroelectric substance (a dielectric material having a high dielectric constant or a substance having a perovskite type crystal structure) has been proposed. The ferroelectric film has characteristics such as spontaneous polarization and high dielectric constant characteristics. Therefore, there is a hysteresis characteristic between the polarization of the ferroelectric substance and the electric field, and by utilizing this, a nonvolatile memory can be realized. In addition, since the dielectric constant is much higher than that of a silicon oxide film, if a ferroelectric film is used as a capacitive insulating film, the memory cell area can be reduced, and a large-capacity, highly integrated RAM (Random Access Memory) can be obtained. ) Can be realized.

The ferroelectric film is made of a sintered body of metal oxide and contains a large amount of highly reactive oxygen. When a capacitor is formed by using such a ferroelectric film as a capacitive insulating film, the upper electrode and the lower electrode of the capacitive insulating film are resistant to an oxidation reaction such as an alloy containing platinum as a main component. It is essential to use stable substances.

After the capacitors and the interlayer insulating film are formed, a passivation film is formed on the outermost surface of the device.
Silicon nitride or silicon oxide is used for the interlayer insulating film and the passivation film, and is generally used for CVD (Chemical Vap
or depositon) method, so hydrogen is often incorporated in the film.

[0005]

When a semiconductor element using a ferroelectric film is used in consumer electronic equipment, it must be a low cost resin-encapsulated semiconductor device with good mass productivity. In particular, ferroelectric non-volatile memory is a low-power, low-voltage non-volatile memory that does not require a refresh operation. There is a demand for a resin-sealed semiconductor device.

At present, however, ceramic-sealed products are the mainstream of devices using a ferroelectric film as a capacitive insulating film, and there are almost no resin-sealed products. Moreover, a large-capacity device has not been developed yet. This is because the polarization characteristics of the ferroelectric film are deteriorated by the heat treatment.

It is known that when a capacitor having a ferroelectric film is annealed in a hydrogen atmosphere, the polarization characteristics are deteriorated ("'96 Ferroelectric thin film memory technology forum lecture collection" (Science Forum Co., Ltd.). Issue) No. 4-
Page 4, lines 1-12). It is speculated that this deterioration occurs because the platinum of the upper and lower electrodes acts with hydrogen to act as a reduction catalyst and reduce the ferroelectric film. In particular, in the case of a large-capacity and highly integrated device, the size of the ferroelectric film also becomes small, so it is expected that the characteristic deterioration of this capacitor will greatly affect the characteristics of the entire device.

A sealing resin containing a filler (usually silica) is used for resin sealing of the semiconductor element by the transfer mold method. However, since the particles of the filler contained in the sealing resin are hard, the filler may damage the element surface during sealing. Further, since the ferroelectric material has piezoelectricity, the characteristics of the ferroelectric film change when pressure is applied to the ferroelectric film in the element during sealing. In addition, DRAM (Dynamic Random Access Memo)
In the production of ry), α-rays are emitted from the radioactive component contained in the filler, which may cause a memory soft error. Therefore, in order to prevent the damage to the device surface by the filler, to prevent the pressurization to the ferroelectric film, and to shield the α ray from the filler, the device surface is protected beforehand by the organic film made of polyimide. It is necessary to form a film. This polyimide surface protective film is usually formed by curing a polyimide precursor composition film by heating it at a temperature of about 350 to 450 ° C. When the polyimide precursor is heat-cured, hydrogen contained in the passivation film or the interlayer insulating film diffuses, so that the polarization characteristics of the ferroelectric film deteriorate. Therefore,
At present, there is no known resin-sealed product of a ferroelectric non-volatile element using a thermosetting resin as a surface protective film.

It is an object of the present invention to provide a highly reliable resin-sealed semiconductor device having a ferroelectric film having good polarization characteristics and a method for manufacturing the same.

[0010]

When the conditions under which the polarization characteristics of the ferroelectric film are deteriorated were examined, it was found that the deterioration occurred when heating at 300 ° C. or higher. Therefore,
The inventors of the present invention performed heat curing of the polyimide surface protective film to 30
It was thought that it may be performed at 0 ° C. or lower, but when a conventional polyimide precursor that cures at such a low temperature is used, there is a problem in solder reflow resistance of the obtained resin-encapsulated semiconductor device.

Currently, the surface mounting method is the mainstream method for mounting a resin-sealed semiconductor device on a printed circuit board. The surface mounting method uses a solder reflow method in which the leads of the semiconductor device and the wiring of the printed circuit board are temporarily fixed with cream solder, and the entire semiconductor device and the substrate are heated for soldering. As a heating method, an infrared reflow method utilizing infrared radiation heat or a vapor phase reflow method utilizing condensation heat of a fluorine-based inert liquid is known.

An epoxy resin is usually used as the sealing resin. This epoxy resin always absorbs moisture under normal environment. During the solder reflow, the resin-sealed semiconductor device is exposed to a high temperature of 215 to 260 ° C.
When a resin-encapsulated semiconductor device is mounted on a substrate by a solder reflow method in a moisture-absorbed state, cracks occur in the encapsulation resin due to rapid evaporation of water, and the reliability of the semiconductor device increases.
It's a big problem. Therefore, various improvements have been made from the viewpoint of lowering moisture absorption and high adhesion of the sealing resin ("Thermosetting Resin" Vol. 13, No. 4 (issued in 1992), page 37, right column, 8 to Line 23, 1996 PROCEEDINGS
46th ELECTRONIC COMPONENTS & TECHNOLOGY CONFERENCE
pp.48-55).

The inventors of the present invention investigated resin cracks generated in a conventional resin-encapsulated semiconductor device, and peeled off at the interface between the polyimide element surface protective film and the encapsulation resin, and this was the starting point for the encapsulation resin. It was found that cracks occur. It was also found that this peeling is affected by the physical properties of the surface protective film, particularly the glass transition temperature and Young's modulus.

Therefore, a more detailed study revealed that when the polyimide element surface protective film is formed by heat treatment in the temperature range of 230 ° C. or higher and 300 ° C. or lower, the deterioration of the polarization characteristics of the ferroelectric film is small. It was Further, the polyimide formed at this heat treatment temperature has a glass transition temperature of 240 ° C. or higher and 400 ° C. or lower, and a Young's modulus of 2 or less.
It was found that in the case of 600 MPa or more and 6 GPa or less, the resin-sealed semiconductor device has excellent solder reflow resistance, peeling does not occur at the interface between the polyimide and the sealing resin during solder reflow, and the reliability is high.

Based on this new finding, the present invention provides a resin-encapsulated semiconductor in which a semiconductor element having a ferroelectric film and a surface protective film and a sealing member made of a resin are provided, and the surface protective film is made of polyimide. A device is provided. Such a device could only be realized by the present invention.

Further, in the present invention, a step of forming a polyimide precursor composition film on the surface of a semiconductor device having a ferroelectric thin film, and heating and curing the polyimide precursor composition film to form a polyimide film There is provided a method of manufacturing a resin-sealed semiconductor device, which includes a step of forming a surface protective film and a step of sealing a semiconductor element having a surface protective film formed thereon with a sealing resin.

The polyimide used as the surface protective film in the present invention has a glass transition temperature of 240 ° C to 400 ° C.
And the Young's modulus is preferably 2600 MPa to 6 GPa. By using such a polyimide, it is possible to obtain a highly reliable semiconductor device in which cracks do not occur even by solder reflow. The temperature at which the polyimide precursor composition film is heated and cured is preferably 230 ° C. or higher and 300 ° C. or lower, but even if the temperature is higher than 300 ° C., a short time of 350 ° C. or lower (even for heat resistance of the semiconductor element used However, the polyimide film formed has a Young's modulus of 3500 MPa or more and a glass transition temperature of 260 ° C.
With the above, the object of the present invention can be achieved without degrading the polarization characteristics of the ferroelectric film.

The manufacturing method of the present invention can also be applied to a resin-sealed laminate using a polyimide film for purposes other than a surface protective film such as an insulating film.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION 230 ° C. to 30 suitable for the present invention
By heat curing at 0 ° C, the glass transition temperature becomes 2
40 ° C to 400 ° C and Young's modulus of 2600M
Examples of the polyimide precursor capable of obtaining a polyimide having Pa of 6 to 6 GPa include a polyamic acid composed of a repeating unit represented by the following general formula (Formula 1).

[0020]

[Chemical 1]

(Wherein R ¹ is at least one of tetravalent aromatic organic groups represented by the following chemical formula group (Chemical Formula 2),
R ² is at least one of divalent aromatic organic groups represented by the following chemical formula groups (Chemical Formula 3) and (Chemical Formula 4). )

[0022]

[Chemical 2]

[0023]

[Chemical 3]

[0024]

[Chemical 4]

Among these polyamic acids, R ¹ is at least one of those listed in the following chemical formula group (Chemical formula 7), and R ² is at least one of those listed in the following chemical formula group (Chemical formula 8). Acids are particularly suitable for the present invention.

[0026]

[Chemical 7]

[0027]

[Chemical 8]

In particular, the following chemical formulas (formula 14) and (formula 16)
To (Chemical Formula 18) are suitable for the present invention. Among these, polyamic acid composed of a repeating unit represented by the chemical formula (Formula 16) is most preferable.

[0029]

[Chemical 14]

[0030]

[Chemical 16]

[0031]

[Chemical 17]

[0032]

[Chemical 18]

The polyamic acid used in the present invention is, in addition to the repeating unit represented by the above (Chemical formula 1), in the molecule, further, if it is 10.0 mol% or less of the total number of repeating units, the above ( It may have the same structure as in Chemical formula 1) and may have a repeating unit having a siloxane group as R ² . At this time, the siloxane group used as R ² is
It may be either an aromatic siloxane group or an aliphatic siloxane group, and may be, for example, at least one of groups having a structure represented by the following chemical formula group (Formula 6).

[0034]

[Chemical 6]

When the composition of the polyimide precursor is liquid or varnish, for example, the composition is applied or sprayed on the surface of the device and, if necessary, heated to a semi-cured state (completely imide). It is possible to form a film by bringing the film into a non-formed state. For example, a means such as spin coating using a spinner may be used. The coating film thickness can be adjusted by the coating means, the solid content concentration of the polyimide precursor composition, the viscosity, and the like. Further, if the polyimide precursor composition is in the form of a sheet, it can be deposited by placing or sticking it on the surface of the device.

An opening for exposing the lower layer is often formed in a desired portion such as a bonding pad portion in the surface protective film. To form such an opening,
A semi-cured polyimide precursor composition film, or by forming a resist film on the surface of the polyimide film after heat curing,
The resist film may be peeled off by patterning with a usual fine processing technique. In the case of opening in a semi-cured state, after patterning, heat treatment is performed to completely cure.

If the polyimide precursor composition is a photosensitive composition, the composition film is exposed through a mask having a predetermined pattern, the unexposed portion is dissolved and removed with a developing solution, and then heat-cured. By doing so, a polyimide film having a desired pattern can be obtained. Therefore, the polyimide precursor composition used in the present invention has, in addition to the above polyamic acid, an amine compound having a carbon-carbon double bond, a bisazide compound, a photopolymerization initiator, and / or a sensitizer. It is desirable that the photosensitive polyimide precursor composition contains

Specific examples of the amine compound include 2-
(N, N-dimethylamino) ethyl acrylate, 2-
(N, N-dimethylamino) ethyl methacrylate, 3
-(N, N-dimethylamino) propyl acrylate,
3- (N, N-dimethylamino) propyl methacrylate, 4- (N, N-dimethylamino) butyl acrylate, 4- (N, N-dimethylamino) butyl methacrylate, 5- (N, N-dimethylamino) pentyl Acrylate, 5- (N, N-dimethylamino) pentyl methacrylate, 6- (N, N-dimethylamino) hexyl acrylate, 6- (N, N-dimethylamino) hexyl methacrylate, 2- (N, N-dimethylamino) ) Ethyl cinnamate, 3- (N, N-dimethylamino) propyl cinnamate, 2- (N, N-dimethylamino)
Ethyl-2,4-hexadienoate, 3- (N, N-
Dimethylamino) propyl-2,4-hexadienoate, 4- (N, N-dimethylamino) butyl-2,4-
Hexadienoate, 2- (N, N-diethylamino)
Ethyl-2,4-hexadienoate, 3- (N, N-
Preferred examples include diethylamino) propyl-2,4-hexadienoate.

These may be used alone, or 2
You may use it in mixture of 2 or more types. It is desirable that the compounding ratio of these is 10 parts by weight or more and 400 parts by weight or less with respect to 100 parts by weight of the polyamic acid polymer.

Specific preferred examples of the bisazide compound include the compounds listed in the structural formula groups (formula 9) and (formula 10) below. These may be used alone or in combination of two or more. The blending ratio of these is 0.5 with respect to 100 parts by weight of the polymer.
It is desirable to use at least 50 parts by weight.

[0041]

[Chemical 9]

[0042]

[Chemical 10]

Preferred examples of the photopolymerization initiator and the sensitizer are Michler's ketone, bis-4,4'-diethylaminobenzophenone, benzophenone, benzoyl ether, benzoin isopropyl ether, anthrone, 1,9-benzanthrone, Acridine, nitropyrene, 1,8-dinitropyrene, 5-nitroacetonaphthene, 2-nitrofluorene, pyrene-1,6-quinone 9-fluorene, 1,2-benzanthraquinone,
Antoanthrone, 2-chloro-1,2-benzanthraquinone, 2-bromobenzanthraquinone, 2-chloro-1,8-phthaloylnaphthalene, 3,5-diethylthioxanthone, 3,5-dimethylthioxanthone,
3,5-diisopropylthioxanthone, benzyl, 1
-Phenyl-5-mercapto-1H-tetrazole, 1
-Phenyl-5-meltex, 3-acetylphenanthrene, 1-indanone, 7-H-benz [de] anthracene-7-one, 1-naphthaldehyde, thioxanthen-9-one, 10-thioxanthenone, 3-acetyl. Examples include, but are not limited to, indole. Moreover, these are used individually or in mixture of 2 or more types. A suitable blending ratio of the photopolymerization initiator and the sensitizer used in the present invention is 0.1 to 3 relative to 100 parts by weight of the polymer.
0 parts by weight is preferred.

As the exposure light source used for the patterning by the photolithography, visible light, radiation, etc. can be used in addition to ultraviolet light.

As the developing solution, N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphoramide, dimethylimidazolidinium An aprotic polar solvent such as non-, n-benzyl-2-pyrrolidone, N-acetyl-ε-caprolactam or γ-butyrolactone may be used alone or
Alternatively, a mixed solution of a poor solvent for a polyamic acid such as methanol, ethanol, isopropyl alcohol, benzene, toluene, xylene, methyl cellosolve, and water, and the above aprotic polar solvent can be used.

The pattern formed by development is then washed with a rinse solution to remove the developing solvent. As the rinse liquid, it is desirable to use a poor solvent of polyamic acid having good miscibility with the developer, and the above-mentioned methanol, ethanol, isopropyl alcohol, benzene, toluene, xylene, methyl cellosolve, water and the like are preferable examples. Can be mentioned.

As a heat treatment method for heating and curing the polyimide precursor composition film, heating with a hot plate is desirable. By using a hot plate, compared to heat treatment using a furnace body such as an oven furnace or a diffusion furnace,
A film can be formed by imidizing a polyimide precursor material in a short time. As a result, it is possible to reduce the heating time for the ferroelectric film.

Examples of the semiconductor device to which the present invention is applied include a non-volatile semiconductor memory and a large capacity DRAM. Further, the ferroelectric film in the semiconductor element may be a film made of a dielectric material having a high dielectric constant, and examples thereof include a film of a ferroelectric material having a perovskite type crystal structure.

As the dielectric material, lead zirconate titanate (Pb (Zr, Ti) O ₃ , abbreviation: PZT), barium strontium titanate ((Ba, Sr) TiO ₃ , abbreviation: BST), niobium tantalate is used. Strontium bismuth (SrBi ₂ (Nb, Ta)
₂ O ₉ , abbreviation: Y1 series) and the like. These materials are chemical vapor deposition (CVP (Chemical Vapor Depositio
n) method), sol-gel method, sputtering method and the like.

Next, regarding an example of the semiconductor device of the present invention,
A lead-on-chip type (hereinafter abbreviated as LOC type) resin-sealed semiconductor device shown in FIG. 1 will be described as an example. In addition,
The semiconductor device of the present invention is not limited to the LOC type, and may be a resin-encapsulated semiconductor device of another form such as a chip-on-lead type (hereinafter abbreviated as COL type).

The sealed semiconductor device of the present invention includes the semiconductor element 1 having the surface protective film 2 made of polyimide on at least a part of the surface thereof, the external terminal 3, and the semiconductor element 1 and the outside through the surface protective film 2. Adhesive member 4 for adhering terminals 3
A wiring 5 for establishing electrical continuity between the semiconductor element 1 and the external terminal 3, and a sealing member 6 for sealing the semiconductor element 1 and the wiring 5 as a whole. The surface protective film 2 is made of polyimide obtained by heating and curing the above polyimide precursor. In the semiconductor device shown in FIG. 1, the external terminal 3 also serves as a lead frame.

Next, an example of a method of manufacturing the semiconductor device of the present invention will be described in detail with reference to FIG. Note that FIG.
Although the manufacturing method of the LOC type semiconductor device shown in FIG. 1 is shown, the manufacturing method of the present invention is not limited to the manufacturing method of the LOC type semiconductor device, and after the semiconductor element and the external terminal (lead frame) are bonded in advance. A semiconductor device obtained by sealing with a mold resin can be applied to the manufacture of other semiconductor devices such as a COL type.

(1) Surface Protective Film Forming Step As shown in FIG. 2A, the surface protective film 2 made of polyimide is formed on the silicon wafer 9 in which the element region and the wiring layer are formed. As a method of forming the surface protective film 2,
For example, a method of applying the above-mentioned polyimide precursor composition to the surface of the wafer 9 and heating and curing, or placing the polyimide precursor composition formed into a sheet shape in advance on the surface of the wafer 9,
There is a method of heating and curing.

As described above, the surface protection film 2 has openings formed at predetermined positions, and the element 1 is formed at the bonding pad 7 and the scribe region 8.
The surface of is exposed. In order to form the surface protection film having a pattern excluding the bonding pad portion 7 and the scribe region 8, a wet etching method using the above-described photoresist and a polyimide etching solution may be used, as well as a patterned inorganic film or a metal film. As a mask, a photoetching technique such as a dry etching method for removing the exposed polyimide film with oxygen plasma can be used. The surface protective film 2 can also be patterned by applying a polyimide precursor composition except for the regions 7 and 8 using a mask.

The scribe region of the silicon wafer 9 having the surface protective film 2 thus formed is cut to obtain the semiconductor element 1 (shown in FIG. 2B) having the surface protective film 2.
Although the method of forming the surface protection film 2 on the silicon wafer 9 in advance and cutting the surface protection film 2 to obtain the semiconductor element 1 having the surface protection film 2 has been described here, the present invention is not limited to this. After the wafer 9 is cut to obtain the semiconductor element 1, a film of the polyimide precursor composition is formed on the surface of the obtained semiconductor element 1, and the film is heat-cured to obtain the semiconductor element 1 having the surface protective film 2. You may get it.

(2) Element mounting process The external terminal 3 and the semiconductor element 1 are adhered via the adhesive member 4, and the semiconductor element 1 and the external terminal 3 as shown in FIG.
And are connected via the surface protection film 2 and the adhesive member 4. Further, as shown in FIG. 2D, a gold wire 5 is laid between the bonding pad portion 7 of the semiconductor element 1 and the external terminal 3 with a wire bonder to secure the conduction between the semiconductor element 1 and the external terminal 3. To do.

(3) Sealing step As shown in FIG. 2 (e), a molding temperature of 180 ° C. and a molding pressure of 70 kg / cm ² were used using a silica-containing epoxy resin.
The sealing member 6 is formed by molding with. Finally, by bending the external terminal 3 into a predetermined shape,
The LOC type resin-sealed semiconductor device shown in FIG. 2F is obtained.

Next, a semiconductor element used in the resin-sealed semiconductor device of the present invention will be described. As an example of a semiconductor element used in the resin-encapsulated semiconductor device of the present invention, 1
FIG. 4 is a sectional view of a memory cell portion of a ferroelectric memory including memory cells of (transistor / 1 capacitor).

This ferroelectric memory device 40 has a p or n well 421 and a source 4 on the surface of a silicon substrate 41.
22 and drain 423, an oxide film 424, a gate 425, and an insulating layer 426.
ntary Metal Oxide Semiconductor) Transistor layer 4
2 is formed on the surface of the insulating film 426, the lower electrode layer 431, the ferroelectric thin film 432, and the upper electrode layer 433.
And a capacitor 43 composed of a metal wiring layer 434 and an insulating layer 435. As described above, the present invention is applied to the case where the polyimide surface protective film is formed on the surface of the laminated body (including the semiconductor element) provided with the ferroelectric thin film 432 and then the resin is sealed. In the example shown in FIG. 4, the polyimide surface protective film is the capacitor 43.
Is formed so as to cover the metal wiring layer 434 and the insulating layer 435.

As described in detail above, the present invention provides a resin-sealed type ferroelectric device having a polyimide surface protective film. The heat curing temperature of the polyimide precursor is 230 ° C.
By setting the temperature to ˜300 ° C., deterioration of the polarization characteristics of the ferroelectric film can be suppressed to a small level. Further, by setting the glass transition temperature of the polyimide constituting the surface protective film to 240 ° C. or higher and the Young's modulus to 2600 MPa or higher, the solder reflow resistance after resin sealing is excellent, and the polyimide and the sealing are performed during solder reflow. A semiconductor device in which peeling does not occur at the resin interface can be obtained. Moreover, even if the heat curing temperature of the polyimide precursor is higher than 300 ° C.,
The temperature is 0 ° C or lower, the heating time is 4 minutes or shorter, and the glass transition temperature of the polyimide obtained after curing is 260 ° C.
By using the polyimide precursor composition having the Young's modulus of 3500 MPa or more, deterioration of polarization characteristics of the ferroelectric film can be suppressed to a small level, and further, solder reflow resistance after resin sealing is excellent, It is possible to obtain a semiconductor device in which peeling does not occur at the interface between the polyimide and the sealing resin during reflow. Therefore, according to the present invention,
A highly reliable semiconductor device can be obtained.

Examples of the present invention will be described below. In addition,
Regarding the polyimide film used in the following examples, Young's modulus and glass transition temperature were measured using a separately prepared polyimide film. That is, first, using a hot plate, under the same conditions as in each example, after forming a polyimide film on a silicon wafer, the polyimide film is peeled from the wafer, washed with water, and dried to form a polyimide film having a film thickness of 9 to 10 μm. Got This polyimide film was cut into a length of 25 mm x width of 5 mm to form a test piece, and an "AUTOGRAPH AG-100E" tensile tester (manufactured by Shimadzu Corp.) was used to pull at a speed of 1 m.
The Young's modulus was obtained by measuring the tensile load and elongation on the film under the condition of m / min. Also, the length of the polyimide film is 1
The test piece was cut into 5 mm x 5 mm width, the load in the extension direction was ² gf (about 4 x 10 ^-2 N / m ² ), and the heating rate was 5 ° C / min. The thermal expansion curve obtained from thermomechanical measurement was obtained using Riko ULVAC), and the glass transition temperature was obtained from this.

The solder reflow resistance of the resin-sealed semiconductor device was measured as follows. First, the semiconductor device was left standing at 85 ° C. and a constant temperature and humidity of 85% for 168 hours to be humidified. The step of heating the humidified semiconductor device at a maximum temperature of 240 to 245 ° C. for 10 seconds and then allowing it to cool to room temperature was repeated three times using an infrared solder reflow furnace.
Then, using an ultrasonic flaw detector, non-destructive observation of interfacial destruction between the polyimide and the sealing resin was carried out to examine the solder reflow resistance of the polyimide surface protective film. The temperature profile of the infrared solder reflow furnace is described in "Mounting Technology of Surface Mount LSI Package and Its Reliability Improvement" on page 451 (Hitachi, Ltd., Semiconductor Division, 1988). The maximum temperature of 240-245 ℃
Was followed as.

The viscosity of the polyimide precursor solution is DVR-
It was measured at 25 ° C. with an E-type viscometer (manufactured by Tokimec Co., Ltd.).

<Example 1> 92.0 g (0.46 mol) of 4,4'-diaminodiphenyl ether and 9.12 g of 4-aminophenyl 4-amino-3-carbonamidophenyl ether under a nitrogen stream. 44 mol)
Was dissolved in 1580.2 g of N-methyl-2-pyrrolidone to prepare an amine solution. Next, add this solution to about 15 °
54.5 g (0.25 mol) of pyromellitic dianhydride and 3,3 ′, while stirring at the temperature of
4,4'-benzophenone tetracarboxylic acid dianhydride 8
A mixture of 0.5 g (0.25 mol) was added. After the addition was completed, the mixture was further stirred and reacted at about 15 ° C. for about 5 hours under a nitrogen atmosphere to obtain a polyimide precursor composition solution having a viscosity of about 30 poise. The obtained polyimide precursor composition solution contains a polyamic acid represented by the following general formula (Formula 1) as a polyimide precursor.

[0065]

[Chemical 1]

However, the polyamic acid of this embodiment is R ¹
But,

[0067]

[Chemical 11]

And R ² is

[0069]

[Chemical 12]

Is a copolymer of In addition, (Chemical formula 11)
In and (Chemical Formula 12), [] represents the ratio of the number of repeating units in one molecule.

A ferroelectric material was used for the capacitance insulating film, a silicon nitride film was formed on the outermost surface, and a wafer having a semiconductor element having a bonding pad portion for electrical connection was prepared.

A PIQ coupler manufactured by Hitachi Chemical Co., Ltd. was spin-coated on this wafer and heated at 300 ° C. for 4 minutes in the air using a hot plate heating device, and then the above polyimide precursor was added. The body composition solution was spin-coated and heated at 140 ° C. for 1 minute in a nitrogen atmosphere using a hot plate heating device.

Next, a positive photoresist "OFPR800" manufactured by Tokyo Ohka Kogyo Co., Ltd. was spin-coated and heated at 90 ° C. for 1 minute by a hot plate heating device to form a resist film on the surface of the polyimide precursor composition film. Was formed, exposed through a photomask and developed to form an opening in the resist film for exposing the underlying polyimide precursor film. Then, it heated at 160 degreeC for 1 minute with the hot plate heating apparatus.

Next, the polyimide precursor composition film was etched by using the alkaline aqueous solution as the resist developing solution as it was, and an opening was formed at the location of the polyimide precursor composition film corresponding to the resist opening. . The resist film is removed with a resist stripping solution and a dedicated rinse solution, the polyimide precursor composition film is washed with water, and then at 230 ° C. for 4 minutes, 30 minutes.
Heating at 0 ° C. for 8 minutes to imidize the polyimide precursor,
A polyimide surface protective film having an opening in the bonding pad portion was formed on the device surface. The thickness of the obtained polyimide film was 2.3 μm. Moreover, when the Young's modulus and the glass transition temperature of the polyimide film were measured as described above, they were about 3700 MPa and about 300 ° C., respectively.

Then, using the polyimide film as a mask, the silicon nitride film covering the bonding pad portion is removed by C
Dry etching was performed with a mixed gas of 94% F ₄ and 6% O ₂ to expose the aluminum electrode in the bonding pad portion.

Here, the residual polarizability of the ferroelectric film, which is an electrical characteristic of the device, was measured, and the value was 5% compared with the residual polarizability of the initial ferroelectric film before the PIQ coupler treatment. It was only decreasing.

Next, this wafer was cut in the scribe region to obtain a semiconductor element having a surface protective film. This semiconductor element was fixed to a lead frame in a die bonding process, and thereafter, a gold wire was wired between a bonding pad portion of the semiconductor element and an external terminal with a wire bonder. Furthermore, using a silica-containing biphenyl epoxy resin manufactured by Hitachi Chemical Co., Ltd., a molding temperature of 180 ° C. and a molding pressure of 70
A resin-sealed portion was formed by sealing with kg / cm ² . Finally, the external terminals were bent into a predetermined shape to obtain a completed resin-encapsulated semiconductor device shown in FIG.

With respect to the obtained resin-encapsulated semiconductor device,
When the solder reflow resistance evaluation test was performed as described above, no peeling or cracking occurred at the interface between the polyimide surface protective film and the sealing epoxy resin, and a highly reliable semiconductor device could be obtained.

<Comparative Example 1> A wafer similar to that of Example 1 was prepared, and PIQ manufactured by Hitachi Chemical Co., Ltd. was placed on the wafer.
After spin-coating the coupler and heating in air at 300 ° C. for 4 minutes with a hot plate heating device, a polyimide precursor solution “PIQ-13” manufactured by Hitachi Chemical Co., Ltd. was spin-coated with a hot plate heating device. The polyimide precursor composition film was formed by heating at 140 ° C. for 1 minute in a nitrogen atmosphere.

Next, in the same manner as in Example 1, after forming an opening in the polyimide precursor composition film, it was heated in a nitrogen atmosphere at 230 ° C. for 4 minutes by a hot plate heating device, and further, in a horizontal diffusion furnace. 30 at 350 ℃ in nitrogen atmosphere
Heated for minutes. As a result, a polyimide film (PIQ-13 film) having an opening in the bonding pad portion was formed on the element surface. The obtained PIQ-13 film has a thickness of 2.3.
was μm. Moreover, when the Young's modulus and the glass transition temperature of the PIQ-13 film were measured as described above, they were about 3300 MPa and about 310 ° C., respectively.

After that, the aluminum electrode of the bonding pad portion was exposed and the residual polarizability of the ferroelectric film was measured in the same manner as in Example 1. As a result, it was found that the value was 60% lower than the value before the PIQ coupler treatment.

Next, a completed resin-encapsulated semiconductor device was prepared in the same manner as in Example 1, and solder reflow resistance was evaluated in the same manner as in Example 1. As a result, a polyimide surface protective film and an encapsulated epoxy resin were prepared. No peeling or cracking occurred at the interface. However, the device obtained in this comparative example is significantly deteriorated in the characteristics of the ferroelectric film as compared with the device of Example 1,
It was not suitable for practical use.

<Comparative Example 2> In the same manner as in Comparative Example 1, a surface protective film was formed on the wafer surface. However, the heating time at 350 ° C. in the heat curing treatment of the polyimide precursor composition film was shortened to 8 minutes. Similarly to Comparative Example 1, the Young's modulus and glass transition temperature of the PIQ-13 film of this Comparative Example were about 3300 MPa and about 310 ° C. However, the residual polarizability of the ferroelectric film in the device of this comparative example is PI
The value was 25% lower than the value before the Q-coupler treatment, and the characteristic deterioration was remarkable as compared with Example 1, which was not suitable for practical use.

Comparative Example 3 A wafer similar to that of Example 1 was prepared, and a polyimide precursor composition “PIX8803-9L” manufactured by Hitachi Chemical Co., Ltd. was spin-coated on this wafer and heated with a hot plate. In a nitrogen atmosphere by the device,
The film was heated at 100 ° C. for 1 minute and further at 230 ° C. for 8 minutes to obtain a semi-cured polyimide precursor composition film.

After forming an opening in this polyimide precursor composition film in the same manner as in Example 1, the film was heated in a nitrogen atmosphere at 230 ° C. for 4 minutes by a hot plate heating device,
A polyimide film (PIX8803-9L film) having an opening in the bonding pad was obtained. The thickness of the obtained polyimide film was 2.3 μm. Moreover, when the Young's modulus and the glass transition temperature of the PIX8803-9L film were measured as described above, they were each about 2000 MPa.
And about 200 ° C.

Next, as in Example 1, the silicon nitride film was dry-etched using the polyimide film as a mask to expose the aluminum electrode in the bonding pad portion, and the residual polarizability of the ferroelectric film was measured. The difference between the measured value and the value before coating the polyimide precursor composition was within 1%, and almost no deterioration of the characteristics was observed.

Next, a completed resin-encapsulated semiconductor device was prepared in the same manner as in Example 1, and solder reflow resistance was evaluated in the same manner as in Example 1. As a result, a polyimide surface protective film and an encapsulated epoxy resin were prepared. Peeling was observed over the entire interface, and only a semiconductor device with extremely low reliability could be obtained.

<Example 2>4,8'-diaminodiphenyl ether 88.0 g (0.44 mol) and 4-aminophenyl 4-amino-3-carbonamido phenyl ether 13.68 g (0. (06 mol) was dissolved in 1584 g of N-methyl-2-pyrrolidone to prepare an amine solution. Next, add this solution to about 15 °
54.5 g (0.25 mol) of pyromellitic dianhydride and 3,3 ′, while stirring at the temperature of
4,4'-benzophenone tetracarboxylic acid dianhydride 8
A mixture of 0.5 g (0.25 mol) was added. After the addition was completed, the mixture was further stirred and reacted at about 15 ° C. for about 5 hours under a nitrogen atmosphere to obtain a polyimide precursor composition solution having a viscosity of about 30 poise. The obtained polyimide precursor composition solution contains, as a polyimide precursor, the same polyamic acid copolymer as in Example 1 except that the copolymerization ratio of R ² was different. R ² in this example is

[0089]

[Chemical 13]

It is In addition, in [Chemical Formula 13], []
The number inside represents the ratio of the number of repeating units in one molecule.

Next, a wafer similar to that of the first embodiment is prepared,
A PIQ coupler manufactured by Hitachi Chemical Co., Ltd. was spin-coated on the surface of the wafer and heated at 260 ° C. for 4 minutes in the air using a hot plate heating device.
The above polyimide precursor composition solution was spin-coated and heated at 140 ° C. in a nitrogen atmosphere with a hot plate heating device at 1 ° C. for 1 hour.
Heated for minutes. As a result, a polyimide precursor composition film was obtained.

After forming an opening in this composition film in the same manner as in Example 1, the polyimide precursor was imidized by heating at 230 ° C. for 4 minutes and 260 ° C. for 8 minutes to form an opening in the bonding pad portion. A certain polyimide surface protective film was formed on the device surface. The thickness of the obtained polyimide film is 2.3 μm
Met. Moreover, when the Young's modulus and the glass transition temperature of the polyimide film were measured as described above, they were about 3300 MPa and about 300 ° C., respectively.

When the residual polarizability of the ferroelectric film was measured, it was only about 2% lower than the residual polarizability of the initial ferroelectric film before the PIQ coupler treatment. Met.

Next, after a resin-encapsulated semiconductor device was completed as in Example 1, a solder reflow resistance evaluation test was carried out on the obtained completed product. No peeling or cracking occurred at the interface of the sealing epoxy resin, and a highly reliable semiconductor device could be obtained.

<Example 3>4,4'-under nitrogen stream
90.0 g (0.45 mol) of diaminodiphenyl ether and 9.6 g (0.05 mol) of bis (3-aminopropyl) tetramethyldisiloxane were dissolved in 1584 g of N-methyl-2-pyrrolidone to prepare an amine solution. .
Next, 147 g (0.5 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added while stirring the solution while maintaining the temperature at about 15 ° C. After the addition was completed, the mixture was further stirred and reacted at about 15 ° C. for about 5 hours under a nitrogen atmosphere to obtain a polyimide precursor composition solution having a viscosity of about 50 poise. The obtained polyimide precursor composition solution,
The polyimide precursor includes a polyamic acid copolymer composed of a first repeating unit represented by the following general formula (Formula 14) and a second repeating unit represented by the following general formula (Formula 15). However, the ratio of the number of second repeating units to the total number of first repeating units and the number of second repeating units in one molecule of polyamic acid is 10%.

[0096]

[Chemical 14]

[0097]

[Chemical 15]

Next, a wafer similar to that of the first embodiment is prepared,
A PIQ coupler manufactured by Hitachi Chemical Co., Ltd. was spin-coated on the surface of the wafer and heated at 260 ° C. for 4 minutes in the air using a hot plate heating device.
The above polyimide precursor composition solution was spin-coated and heated at 140 ° C. in a nitrogen atmosphere with a hot plate heating device at 1 ° C. for 1 hour.
Heated for minutes. As a result, a polyimide precursor composition film was obtained.

After forming an opening in this composition film in the same manner as in Example 1, the polyimide precursor was imidized by heating at 230 ° C. for 4 minutes and 260 ° C. for 8 minutes to form an opening in the bonding pad portion. A certain polyimide surface protective film was formed on the device surface. The thickness of the obtained polyimide film is 2.3 μm
Met. Further, when the Young's modulus and the glass transition temperature of the polyimide film were measured as described above, they were about 3000 MPa and about 255 ° C., respectively.

Here, when the residual polarizability of the ferroelectric film was measured, it was only about 2% lower than the residual polarizability of the initial ferroelectric film before the PIQ coupler treatment. Met.

Next, a resin-encapsulated semiconductor device was completed as in Example 1, and a solder reflow resistance evaluation test was conducted on the obtained completed product. No peeling or cracking occurred at the interface of the sealing epoxy resin, and a highly reliable semiconductor device could be obtained.

<Example 4>3,3'-under nitrogen stream
Dimethylbenzidine 103.0 g (0.5 mol) was added to N-
Methyl-2-pyrrolidone dissolved in 1474.5 g, 4,
155.0 g (0.5 mol) of 4'-oxyphthalic dianhydride was added. After the addition was completed, the mixture was further stirred and reacted at about 15 ° C. for about 5 hours under a nitrogen atmosphere to obtain a polyimide precursor composition solution having a viscosity of about 30 poise. The obtained polyimide precursor composition solution contains, as a polyimide precursor, a polyamic acid having a repeating unit represented by the following general formula (Formula 16).

[0103]

[Chemical 16]

Next, a wafer similar to that used in Example 1 was prepared, and a PIQ manufactured by Hitachi Chemical Co., Ltd. was placed on the wafer surface.
After spin-coating the coupler and heating in air at 240 ° C. for 4 minutes using a hot plate heater, the above-mentioned polyimide precursor composition solution was spin-coated in a nitrogen atmosphere with a hot plate heater. 140
Heated at 0 ° C for 1 minute. As a result, a polyimide precursor composition film was obtained.

After forming an opening in this composition film in the same manner as in Example 1, the polyimide precursor was imidized by heating at 230 ° C. for 4 minutes and 240 ° C. for 10 minutes to form an opening in the bonding pad portion. A certain polyimide surface protective film was formed on the device surface. The thickness of the obtained polyimide film is 2.3μ.
It was m. When the Young's modulus and the glass transition temperature of the polyimide film were measured as described above, they were about 4000 MPa and about 250 ° C., respectively.

When the remanent polarizability of the ferroelectric film was measured, the decrease in the remanent polarizability of the ferroelectric film was within about 1% as compared with the initial remanent polarizability of the ferroelectric film before the PIQ coupler treatment. It was

Next, after a resin-encapsulated semiconductor device was completed as in Example 1, a solder reflow resistance evaluation test was performed on the obtained completed product. No peeling or cracking occurred at the interface of the sealing epoxy resin, and a highly reliable semiconductor device could be obtained.

Example 5 Polyimide precursor polymer 100 was added to the polyimide precursor composition solution synthesized in Example 1.
20.0 parts by weight of 3- (N, N-dimethylamino) propyl methacrylate and 2,6-di (p-
5.0 parts by weight of azidobenzal) -4-carboxycyclohexanone was added and dissolved to obtain a photosensitive composition solution.

Next, a wafer similar to that used in Example 1 was prepared, and a PIQ manufactured by Hitachi Chemical Co., Ltd. was placed on the surface of the wafer.
The coupler was spin-coated and heated in air at 250 ° C. for 4 minutes using a hot plate heating device, and then the above photosensitive composition solution was spin-coated in a nitrogen atmosphere with a hot plate heating device. Heated at 85 ° C for 1 minute, followed by 95 ° C for 1 minute. As a result, a polyimide precursor composition film was obtained.

This composition film was exposed through a photomask, developed with a mixed solution of 4 volumes of N-methyl-2-pyrrolidone and 1 volume of ethanol, and then rinsed with ethanol to open at the bonding pad portion. Parts were formed. Next, by using a hot plate heating device, the polyimide precursor is cured by sequentially heating at 130 ° C. for 4 minutes, 170 ° C. for 4 minutes, 220 ° C. for 4 minutes, and 250 ° C. for 8 minutes to open the bonding pad. A polyimide film having The thickness of the obtained polyimide film was 2.3 μm. Moreover, when the Young's modulus and the glass transition temperature of the polyimide film were measured, they were about 3300 MPa and about 300 ° C., respectively.

When the remanent polarizability of the ferroelectric film was measured, the decrease in the remanent polarizability of the ferroelectric film was within about 1% as compared with the initial remanent polarizability of the ferroelectric film before the PIQ coupler treatment. It was

Next, a resin-encapsulated semiconductor device was completed in the same manner as in Example 1, and a solder reflow resistance evaluation test was conducted on the obtained completed product. No peeling or cracking occurred at the interface of the sealing epoxy resin, and a highly reliable semiconductor device could be obtained.

<Example 6> Polyimide precursor polymer 100 was added to the polyimide precursor composition solution synthesized in Example 2.
20.0 parts by weight of 3- (N, N-dimethylamino) propyl methacrylate and Michla ketone 3.
0 parts by weight and 3.0 parts by weight of bis-4,4′-diethylaminobenzophenone were added and dissolved to obtain a photosensitive composition solution.

Next, a wafer similar to that used in Example 1 was prepared, and a PIQ manufactured by Hitachi Chemical Co., Ltd. was placed on the surface of the wafer.
The coupler was spin-coated and heated in air at 270 ° C. for 4 minutes using a hot plate heating device, and then the above photosensitive composition solution was spin-coated in a nitrogen atmosphere with a hot plate heating device. Heated at 85 ° C for 1 minute, followed by 95 ° C for 1 minute. As a result, a polyimide precursor composition film was obtained.

After forming an opening in this composition film in the same manner as in Example 5, the film was heated to 13 by a hot plate heating device.
4 minutes at 0 ℃, 4 minutes at 170 ℃, 4 minutes at 220 ℃,
The polyimide precursor was cured by sequentially heating at 270 ° C. for 8 minutes to form a polyimide film having an opening portion in the bonding pad portion. The thickness of the obtained polyimide film is 2.3 μm
Met. Also, when Young's modulus and glass transition temperature of the polyimide film were measured, each was about 3300MP.
a and about 300 ° C.

Here, when the residual polarizability of the ferroelectric film was measured, the decrease in the value was within about 1% as compared with the residual polarizability of the initial ferroelectric film before the PIQ coupler treatment. It was

Next, after a resin-encapsulated semiconductor device was completed as in Example 1, a solder reflow resistance evaluation test was performed on the obtained completed product. No peeling or cracking occurred at the interface of the sealing epoxy resin, and a highly reliable semiconductor device could be obtained.

Example 7 Polyimide precursor polymer 100 was added to the polyimide precursor composition solution synthesized in Example 3.
20.0 parts by weight of 3- (N, N-dimethylamino) propyl methacrylate and 2,6-di (p-
5.0 parts by weight of azidobenzal) -4-carboxycyclohexanone was added and dissolved to obtain a photosensitive composition solution.

Next, a wafer similar to that used in Example 1 was prepared, and a PIQ manufactured by Hitachi Chemical Co., Ltd. was placed on the surface of the wafer.
The coupler was spin-coated and heated in air at 260 ° C. for 4 minutes using a hot plate heating device, and then the above photosensitive composition solution was spin-coated in a nitrogen atmosphere with a hot plate heating device. Heated at 85 ° C for 1 minute, followed by 95 ° C for 1 minute. As a result, a polyimide precursor composition film was obtained.

After forming an opening in this composition film in the same manner as in Example 5, the film was heated to 13 by a hot plate heating device.
4 minutes at 0 ℃, 4 minutes at 170 ℃, 4 minutes at 220 ℃,
The polyimide precursor was cured by sequentially heating at 260 ° C. for 8 minutes to form a polyimide film having an opening portion in the bonding pad portion. The thickness of the obtained polyimide film is 2.3 μm
Met. Moreover, when Young's modulus and glass transition temperature of the polyimide film were measured, each was about 3000 MP
a and about 260 ° C.

Here, when the residual polarizability of the ferroelectric film was measured, the decrease in the value was within about 2% as compared with the residual polarizability of the initial ferroelectric film before the PIQ coupler treatment. It was

Next, after a resin-encapsulated semiconductor device was completed as in Example 1, a solder reflow resistance evaluation test was conducted on the obtained completed product. No peeling or cracking occurred at the interface of the sealing epoxy resin, and a highly reliable semiconductor device could be obtained.

Example 8 Polyimide precursor polymer 100 was added to the polyimide precursor composition solution synthesized in Example 4.
20.0 parts by weight of 3- (N, N-dimethylamino) propyl methacrylate and Michla ketone 3.
0 parts by weight and 3.0 parts by weight of bis-4,4′-diethylaminobenzophenone were added and dissolved to obtain a photosensitive composition solution.

Next, a wafer similar to that in Example 1 was prepared, the surface of the wafer was treated with a “PIQ coupler” in the same manner as in Example 5, and then the above-described photosensitivity was performed in the same manner as in Example 5. The composition solution was applied and heated to form a polyimide precursor composition film.

The composition film was subjected to an opening treatment in the same manner as in Example 5 and then heat-cured in the same manner as in Example 5 to form a polyimide film. The thickness of the obtained polyimide film is 2.3μ.
It was m. Also, when Young's modulus and glass transition temperature of the polyimide film were measured, each was about 4000M.
Pa and about 250 ° C.

When the remanent polarizability of the ferroelectric film was measured, the decrease in the remanent polarizability of the ferroelectric film was within about 1% as compared with the initial remanent polarizability of the ferroelectric film before the PIQ coupler treatment. It was

Next, after completing a resin-encapsulated semiconductor device as a finished product in the same manner as in Example 1, a solder reflow resistance evaluation test was performed on the obtained finished product. No peeling or cracking occurred at the interface of the sealing epoxy resin, and a highly reliable semiconductor device could be obtained.

<Embodiment 9> A wafer similar to that of Embodiment 1 is prepared, and the wafer surface is provided with PI manufactured by Hitachi Chemical Co., Ltd.
The Q coupler was spin-coated and heated in air at 230 ° C. for 4 minutes using a hot plate heating device, and then the polyimide precursor composition solution synthesized in Example 4 was spin-coated and heated by a hot plate heating device. It heated at 140 degreeC in nitrogen atmosphere for 1 minute. As a result, a polyimide precursor composition film was obtained.

After forming an opening in this composition film in the same manner as in Example 4, it was heated to 20 by a hot plate heating device.
The polyimide precursor was cured by heating at 0 ° C. for 4 minutes and then at 230 ° C. for 10 minutes to obtain a polyimide surface protective film having openings in the bonding pad portion. The thickness of the obtained polyimide film was 2.3 μm. Also, when Young's modulus and glass transition temperature of the polyimide film were measured as described above, they were about 4000 MPa and about 2 MPa, respectively.
It was 50 ° C.

When the residual polarizability of the ferroelectric film was measured, the deterioration due to the heat treatment was about 1 as in Example 4.
It was within%. Further, after the resin-encapsulated semiconductor device was completed as in Example 1 to obtain a finished product, the solder reflow resistance of the obtained finished product was as good as in Example 4.

Example 10 To the polyimide precursor solution synthesized in Example 4, 20.0 parts by weight of 3- (N, N-dimethylamino) propyl methacrylate was added to 100 parts by weight of the polyimide precursor polymer. , Mihiraketone 6.0
The solution was added with parts by weight and dissolved to obtain a photosensitive composition solution.

Next, a wafer similar to that in Example 1 was prepared, the surface of the wafer was treated with a “PIQ coupler” in the same manner as in Example 9, and then the above photosensitive composition solution was spin-coated. A polyimide precursor composition film was formed by heating at 85 ° C. for 1 minute and then at 95 ° C. for 1 minute in a nitrogen atmosphere with a hot plate heating device.

After forming an opening in this composition film in the same manner as in Example 5, the film was heated to 13 by a hot plate heating device.
4 minutes at 0 ℃, 4 minutes at 170 ℃, 4 minutes at 200 ℃,
The polyimide precursor was cured by sequentially heating at 230 ° C. for 10 minutes to form a polyimide film having an opening portion in the bonding pad portion. The thickness of the obtained polyimide film is 2.3μ.
It was m. Also, when Young's modulus and glass transition temperature of the polyimide film were measured, each was about 4000M.
Pa and about 250 ° C.

When the residual polarizability of the ferroelectric film was measured, the deterioration due to the heat treatment was about 1 as in Example 4.
It was within%. Further, after the resin-encapsulated semiconductor device was completed as in Example 1 to obtain a finished product, the solder reflow resistance of the obtained finished product was as good as in Example 4.

<Example 11>3,3'-under nitrogen stream
Dimethylbenzidine 95.4 g (0.45 mol) and bis (3-aminopropyl) tetramethyldisiloxane 9.6 g (0.05 mol) were dissolved in N-methyl-2-pyrrolidone 1040 g to prepare an amine solution. Was prepared.
Next, while maintaining this solution at about 15 ° C. while stirring, 4,5.0 g of 4,4′-oxyphthalic acid dianhydride was obtained.
(0.5 mol) was added, and the mixture was further stirred at about 15 ° C. for about 8 hours in a nitrogen atmosphere to obtain a polyimide precursor solution having a viscosity of about 30 poise.

The obtained polyimide precursor solution contains, as a polyimide precursor, a first repeating unit represented by the above general formula (Formula 16) and a first repeating unit represented by the following general formula (Formula 19). And a polyamic acid copolymer composed of units. However, the number of second repeating units in one molecule of polyamic acid was about 10% of the whole. Using the obtained polyimide precursor solution, a photosensitive composition solution was prepared in the same manner as in Example 5.

[0137]

[Chemical 19]

Next, a wafer similar to that used in Example 1 was prepared, the obtained photosensitive composition solution was spin-coated on the surface of the wafer, and a hot plate heating device was used to perform 1-hour heating at 85 ° C. in a nitrogen atmosphere. After heating for 1 minute at 95 ° C. for 1 minute and then exposing through a photomask, N-methyl-2-
It was developed with a mixed solution of 4 volumes of pyrrolidone and 1 volume of ethanol, and rinsed with ethanol to form an opening for exposing the bonding pad section. Then, using a hot plate device, in a nitrogen atmosphere at 130 ° C. for 3 minutes, 1
The polyimide was cured by sequentially heating at 70 ° C. for 3 minutes, 220 ° C. for 3 minutes, and 300 ° C. for 6 minutes. The thickness of the obtained polyimide film was 2.3 μm. The Young's modulus of this polyimide was about 4000 MPa, and the glass transition temperature was 260 ° C.

Here, the residual polarizability of the ferroelectric film was measured, and as compared with the residual polarizability of the initial ferroelectric film before the application of the polyimide precursor solution, the decrease in the value was within 1%. there were.

Next, a resin-encapsulated semiconductor device was completed as in Example 1, and a solder reflow resistance evaluation test was conducted in the same manner as in Example 1. Example 1
It was just as reliable as.

<Embodiment 12> In this embodiment, heating after formation of the opening is performed at 130 ° C. for 3 minutes and 170 ° C. for 3 minutes.
A resin-encapsulated semiconductor device was produced in the same manner as in Example 11 except that the temperature was 3 minutes at 20 ° C. and the temperature was 350 ° C. for 2 minutes. The same as in Example 11.

Here, the residual polarizability of the ferroelectric film was measured, and as compared with the initial residual polarizability of the ferroelectric film before the application of the polyimide precursor solution, the decrease in the value was within 5%. there were.

Next, after completing a resin-encapsulated semiconductor device in the same manner as in Example 1, a solder reflow resistance evaluation test was performed in the same manner as in Example 1. It was reliable.

[0144]

As described above in detail, in the present invention, since the heat curing temperature of the polyimide precursor is 230 ° C. to 300 ° C., the polarization characteristic deterioration of the ferroelectric film is small. Further, the glass transition temperature of the polyimide obtained by heating and curing is 2
Since the temperature is 40 ° C. or higher and the Young's modulus is 2600 MPa or higher, the solder reflow resistance of the semiconductor device after resin sealing is excellent, and peeling does not occur at the interface between the polyimide and the sealing resin during solder reflow. In addition, even if the temperature is higher than 300 ° C., the heat treatment is performed at a temperature of 350 ° C. or less for a short time (usually within 4 minutes depending on the heat resistance of the semiconductor element to be used), and the Young's modulus of the formed polyimide film is 3500 MP.
When the temperature is a or higher and the glass transition temperature is 260 ° C. or higher, the object of the present invention can be achieved without deteriorating the polarization characteristics of the ferroelectric film. Therefore, according to the present invention, a highly reliable semiconductor device can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a LOC (Lead on Chip) type resin-sealed semiconductor device.

FIG. 2 is an explanatory diagram showing an example of a manufacturing process of a resin-sealed semiconductor device.

FIG. 3 is a cross-sectional view of the resin-sealed semiconductor device manufactured in Example 1.

FIG. 4 is a cross-sectional view showing a configuration example of a semiconductor element having a ferroelectric film.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Semiconductor element, 2 ... Surface protective film, 3 ... External terminal (lead frame) 4 ... Adhesive member, 5 ... Metal wire 6 ... Sealing member, 7 ... Bonding pad section, 8 ... Scribe area, 9 ... Element area Silicon wafer 40 with built-in wiring layer ... Ferroelectric memory element, 41 ... Silicon substrate, 42 ... CMOS transistor layer, 421 ...
p or n well, 422 ... Source,
423 ... drain, 424 ... oxide film,
425 ... Gate, 426 ... Insulating layer,
43 ... Capacitor, 431 ... Lower electrode layer,
432 ... Ferroelectric thin film, 433 ... Upper electrode layer, 434 ... Metal wiring layer, 435 ...
Insulation layer.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI H01L 21/56 H01L 23/12 501V 23/12 501 27/10 451 23/31 23/30 D 27/10 451 (56) Reference Documents JP-A-9-293837 (JP, A) JP-A-7-221259 (JP, A) JP-A-9-142844 (JP, A) JP-A-6-73178 (JP, A) JP-A-7- 78840 (JP, A) JP 7-302863 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 23/29 C08G 73/10 C08L 79/08 C09D 179/08 H01L 21/312 H01L 21/56 H01L 23/12 501 H01L 23/31 H01L 27/10 451

Claims (9)

(57) [Claims] 1. A semiconductor device having a ferroelectric film and a device surface protection film, and a sealing member made of a resin for sealing the semiconductor device , wherein the surface protection film is a thermosetting polyimide.
Therefore, the glass transition temperature is 240 ° C to 400 ° C.
Has a Young's modulus of 2600 MPa to 6 GPa
It is Te resin-encapsulated semiconductor device according to claim. 2. The ferroelectric film is a capacitance insulator of a capacitor.
The resin-sealed semiconductor device according to claim 1, which is a film . 3. The perovskite type crystal is used as the ferroelectric film.
2. The resin-encapsulated semiconductor device according to claim 1, which is made of a dielectric material having a structure . 4. A semiconductor device having a ferroelectric film and a device surface protection film.
A conductor element and a sealing part made of resin for sealing the semiconductor element
And a surface protection film of 230 ° C. or higher and 300 ° C.
A resin-encapsulated semiconductor device, which is obtained by curing by heating below . 5. A semiconductor device having a ferroelectric film and a device surface protection film.
A conductor element and a sealing part made of resin for sealing the semiconductor element
And the surface protection film is higher than 300 ° C.
Resin obtained by curing at a temperature of 0 ° C. or less for 4 minutes or less
Sealed semiconductor device. 6. A semiconductor device having a ferroelectric film and a device surface protection film.
A conductor element and a sealing part made of resin for sealing the semiconductor element
And the surface protection film is higher than 300 ° C.
It was obtained by curing by heating at a temperature of 0 ° C. or lower for 4 minutes or less, and the Young's modulus was 3500.
A resin-encapsulated semiconductor device having a MPa or higher and a glass transition temperature of 260 ° C. or higher . 7. A half having a ferroelectric film and a device surface protection film.
A conductor element and a sealing part made of resin for sealing the semiconductor element
And the surface protective film is a thermosetting polyimide.
Then, the polyimide precursor composition is heated to 230 ° C. or higher and 300 ° C.
A resin-encapsulated semiconductor device, which is obtained by curing by heating below . 8. A semiconductor device having a ferroelectric film and a device surface protection film.
A conductor element and a sealing part made of resin for sealing the semiconductor element
And the surface protective film is a thermosetting polyimide.
Then, the polyimide precursor composition is higher than 300 ° C.
A tree obtained by curing the resin by heating at a temperature of 50 ° C. or lower for 4 minutes or less.
Oil-sealed semiconductor device. 9. A semiconductor device having a ferroelectric film and a device surface protection film.
A conductor element and a sealing part made of resin for sealing the semiconductor element
And the surface protective film is a thermosetting polyimide.
Then, the polyimide precursor composition is higher than 300 ° C.
It was obtained by curing by heating at a temperature of 50 ° C. or lower for 4 minutes or less, and a Young's modulus of 350.
A resin-sealed semiconductor device having a glass transition temperature of 0 MPa or more and a glass transition temperature of 260 ° C. or more .