JPS63307797A - Multilayer interconnection substrate and manufacture thereof - Google Patents

Abstract

PURPOSE:To improve the degree of integration of wirings while preventing the peeling of a resin film from a substrate by selecting glass and a polyimide resin, thermal expansion coefficients of which are close mutually, and respectively forming a glass thick-film multilayer section and a polyimide resin thin-film multilayer section while laminating both multilayer sections. CONSTITUTION:Glass 1 and a polyimide resin 6, thermal expansion coefficients of which are close mutually, are selected as upper and lower insulating layers 1, 6, a glass thick-film multilayer section is formed by the former, and a polyimide resin thin-film multilayer section is shaped by the latter, and both multilayer sections are laminated. The glass thick-film multilayer section is formed by shaping and laminating respectively corresponding wirings 3 on layers and via holes 2 in thick-films to a plurality of the glass insulating layers 1, and the polyimide resin thin-film multilayer section is formed by shaping and laminating wirings 8 on layers and via holes 7 by thin-films and plating at every layer in the polyimide resin insulating layer 6.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a multilayer wiring board and a method for manufacturing the same, particularly a highly integrated, large-area, high-speed board having a large number of fine interlayer wirings with high positional accuracy. The present invention relates to a wiring board for signal propagation processing and a manufacturing method thereof.

[Prior Art] A multilayer wiring board on which multiple highly integrated LSIs and the like are mounted has an extremely large number of interlayer wirings (hereinafter referred to as dia).
The number of LSI elements on a board used in the central logical operation unit of an electronic computer reaches several tens, and the number of diamonds reaches tens of thousands.

In addition, in the multilayer board mentioned above, the formation of large-capacity wiring to supply power to each mounted element, multilayering of low-resistance wiring using a low dielectric constant insulating material for high-speed signal processing between elements, and For connection with elements, it is necessary to form fine connection terminals with high positional accuracy on the substrate surface.

Conventionally, this type of multilayer wiring board has been produced by forming large-capacity wiring using a sintered ceramic thick film circuit board manufacturing technology called the green sheet thick film method, and by using a thin film circuit board manufacturing technology that uses a low dielectric constant organic polymer as an insulating film between all layers. Manufactured by pattern formation with high positional accuracy.

For example, the green sheet thick film method for forming large capacity wiring is as follows. A green (green) sheet is produced by mixing powder mainly composed of alumina, an organic binder and an organic bath agent, and using a doctor blade method. This green sheet is cut to the required size, through holes for diamonds are formed in the sheet by mechanical processing such as punching or drilling, and then 5W or Mo is formed by thick film screen printing according to each circuit pattern.
A conductive paste is filled into the through holes, and a wiring film is formed on the sheet. After that, a predetermined number of sheets that have been distributed by MA are laminated under pressure and heated to 1600°C by H, -N.
, -)1. (Heat treatment is performed in a non-oxidizing atmosphere such as J and sintered on the green sheet laminate to produce a ceramic thick film multilayer wiring board.

A thin film multilayer wiring circuit using polyimide resin as an insulating layer on a ceramic substrate is manufactured, for example, in the following manner. First, polyimide resin is coated on a ceramic multilayer wiring board using a spinner, and after hardening by heating, a photoresist l is applied on top of this.
1ie is formed by heating and curing. Furthermore, a through hole for a diamond for connecting the thick film multilayer wiring circuit and the thin film multilayer wiring circuit is formed on the resist film by mask exposure, development, plasma etching, etc., and the through hole is filled with a Cu conductor by electroless plating. be done. Subsequently, a Cr film and a Cu film are formed on the entire surface of the substrate by spatter deposition, and a photosensitive resist film is formed on the Cu film except for the areas that will become wiring conductors, and KCu metallization is formed on the parts that will become wiring conductors. be done. Next, the photosensitive resist film is removed, and the Cu film and Cr film below this resist film are etched away, and wiring is formed on the polyimide resin film. Then, form a polyimide resin film again, form a resist film, form a through hole pattern on the photoresist film, form a through hole in the polyimide resin film by plasma etching, fill the inside of the through hole with a conductor by electroless Cu plating, and sputter deposition. Cr film, C
U film formation, photosensitive resist film formed except for the 184 locations, electroless plating, removal of the photosensitive resist film, removal of Cu film and Cr film under the photosensitive resist film, etc. A thin film multilayer circuit is formed by repeating all steps a predetermined number of times.

For information related to this glazed multilayer circuit board, see Nikkei Electronics August 27, 1984 issue, p.
pl 45-159.

[Problem that the invention seeks to solve]

The above conventional technology has the following problems and limitations.

First, the formation of through-holes in the green sheets for the diamonds of the ceramic thick-film multilayer wiring board cannot be performed simultaneously on all the green sheets because mechanical processing methods such as punching and drilling are used. For this reason, as the number of through holes increases to more than 50 holes/cId and the spacing between the through holes narrows to 1W or less, the green sheet becomes sagging and distorted, resulting in a decrease in positional accuracy. Sometimes it took time.

Second, the green sheet laminate is reduced to 15% by heat treatment.
Sintering shrinks during summer, but the accuracy of this shrinkage rate is ±L1.
% is the limit for mass production, and ceramic multilayer wiring boards manufactured by sintering inevitably have a dimensional error exceeding ±0.5%, and this dimensional error is, for example, ±500 μm for a board with 100 corners. becomes.

Sixth, in order to absorb dimensional errors in ceramic thick film multilayer wiring boards, the advantage of technically possible formation of fine, highly dense patterns in thin film multilayer circuits may be reduced.

For @4, we used a polyimide resin film because of the large thermal expansion coefficient of the alumina substrate (7 x 107/T:) and the large thermal expansion coefficient of the polyimide flank (2,0 x 10'/°C), which are conventionally widely used as ceramics. The application area is wide,
Further, as the film thickness increases, the polyimide greasy film tends to peel off from the ceramic substrate, and there are also problems such as there being a limit to the scale and number of layers of a thin film multilayer circuit.

An object of the present invention is to provide a multilayer wiring board and a method for manufacturing the same that can solve the above-mentioned problem, enable high integration of wiring, and prevent peeling between the resin film and the board. .

[Means for solving problems]

The present invention provides a multilayer wiring board formed by alternately stacking wiring layers and insulating layers having dia for electrically connecting the upper and lower wirings, as a means for solving the above-mentioned problems. As a result, glass tophorimide resins having similar coefficients of thermal expansion are selected, and the former forms a glass thick film multilayer part, and the latter forms a polyimide resin thin film multilayer part, and both are laminated. The film multilayer part is formed by laminating a plurality of glass insulating layers with thick film wiring and diamonds on each layer. It is characterized in that it is constructed by forming a thin film and a wiring layer and a diamond layer on each layer and stacking them.

Further, as a means for solving the above problems, the present invention provides a multilayer wiring board in which wiring layers and insulating layers having wiring for electrically connecting upper and lower wirings are laminated alternately to perform multilayer wiring. In the manufacturing method, a plurality of glass layers having a coefficient of thermal expansion similar to that of the polyimide resin are arranged, and through holes are formed at predetermined positions R of each glass layer by etching through a mask. After that, thick film conductors are printed to provide layered wiring, the through holes are filled with thick film conductors to form diamonds, and the above glass insulating layers are laminated and melted to form a single glass thick film. A multilayer part is formed, and a polyimide resin insulating layer is laminated on the top layer of the glass thick film multilayer part, and the polyimide side insulating layer is provided with a through hole for each resin layer to be laminated, and is formed by thin film and plating. When an on-layer wiring is provided, the through hole is made conductive to form a dia.

The glass insulating layer constituting the glass thick film multilayer section is preferably selected from one having a coefficient of thermal expansion of s, oxl[T'/° C. or higher. Further, as the polyimide resin constituting the polyimide resin thin film multilayer section, a polyimide resin having a coefficient of thermal expansion of 2.0 x 101/l or less is preferably selected.

[Effect]

A photosensitive glass plate is closely exposed using a patterned light-shielding mask to precipitate microcrystals that are easily acid-etched under the exposure partial pressure. can be formed. The present invention forms this through hole and uses nine glass plates by compressing the green sheet of the prior art, Ag,
Au, Ag/Pd, Ag/Pt, Au/Pt
Alternatively, a conductive paste such as Cu is used as the wiring material, and wiring, terminal formation, and diamond filling are performed by thick film screen printing.

Next, after laminating the wired glass plates according to the predetermined circuit layers, the glass plates are heat-treated at 800 to 900°C to integrate them, and the glass plates are changed into crystallized glass with high mechanical strength, and the wiring material is Baked on glass. The dimensional change due to heat treatment is less than 12%, and its accuracy is less than ±CLO5%, and the dimensional accuracy can be improved by one order of magnitude compared to the conventional method.

Due to the above-mentioned effects, thin film multilayer wiring circuits can be formed with higher density and finer details.

Furthermore, since the present invention greatly reduces the difference in thermal expansion coefficient between the glass multilayer wiring board and the polyimide resin, the film thickness of the polyimide resin formed on the glass multilayer wiring board can be made thicker and larger than before. Since it can be formed over a large area, it is highly integrated,
Large-scale multilayer wiring boards can be back-circuited.

[Example] An example of a multilayer wiring board and a method for tearing the same according to the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing the structure of an embodiment of a multilayer wiring board based on the misfire 8A.

In FIG. 1, the multilayer wiring board of this embodiment is constructed by laminating a glass thick film multilayer part q and a polyimide resin # film multilayer part P.

The glass thick film multilayer part q is formed by laminating a plurality of (four in this embodiment) glass insulating layers 1 with corresponding on-layer wiring 3 and dia 2 made of thick film. As the glass forming the glass insulating layer 1, a glass whose coefficient of thermal expansion is close to that of polyimide resin is selected. In this embodiment, a temperature of aO×1σ1/° C. or higher is selected. As will be described later, the dia 2 is formed by etching a through hole at a corresponding position in each glass insulating layer IK and filling the through hole with a thick film conductor. The layer wiring 3 is printed on each glass insulating layer 1)
Form.

Further, the glass thick film multi-layer part G is made by laminating the above-mentioned glass insulating layers 1, melting them, and integrating them. Thick film terminals 4 for input/output are provided in advance on the lower layer surface of the glass thick film multilayer portion G. This input/output thick film terminal 4 is connected to the dia 2 and provided.

Further, on the upper surface of the glass thick film multilayer portion G, a thick film terminal 5 for thin film circuit connection is provided.

The above-mentioned polyimide resin thin film multilayer part P has a polyimide resin insulating layer 6 formed by thin film and plating for each layer to form wiring 8 on the υ layer.
and dia 7 are provided and stacked. As the resin forming the polyimide resin insulating layer 6, a resin whose coefficient of thermal expansion is close to that of the glass insulating layer 1 is selected. In this embodiment, 2. OX 10-'/'C or less is selected.

In addition, in this example, the polyimide resin thin film multilayer part P is as follows:
For example, by applying and curing a polyimide resin by the method described later, a polyimide resin insulating layer 6 having a thickness of 30 μm is formed, and the above-mentioned layers Iw8 and Dia 7 are provided thereon, and then the same 5I! Then, a polyimide resin insulating layer 6 is formed to have a multilayer structure. In this embodiment, a 25-layer structure is used. The diamonds 7 are placed at corresponding positions on the polyimide resin insulating layer 6.
As will be described later, a through hole is provided by plasma etching, and a zero conductor is filled in this through hole by non-flL deplating. The layered edges 8 are formed at corresponding positions on each layer of the polyimide resin insulating layer 6 by etching, sputter linking, 7F etching, and electroless plating, as will be described later.

The dia 7 provided in the lowermost layer of the polyimide porridge insulation layer 6 is connected to the thick film terminal 5 for thin film circuit connection provided in the upper layer of the glass thick film multilayer part q. Furthermore, LSI connection terminals 9 and other surface terminals 10 are provided on the top layer of the polyimide resin insulation j-6. These elements 9 and 10 are each connected to the dia 7 provided on the top layer of the polyimide resin insulating layer 6.

Next, a method of manufacturing the multilayer wiring board configured as described above will be explained with reference to FIGS. 1 and 2.

FIG. 2 is a flowchart showing the manufacturing process of the multilayer wiring board.

The manufacturing process of the multilayer wiring board of this embodiment basically consists of the following steps: (1) manufacturing a thick film multilayer wiring board, (2) manufacturing a thin film multilayer wiring circuit, and (2) manufacturing a multilayer wiring circuit board. This)@ will be explained below.

(1) Production of thick film multilayer wiring board First, a fine 1t (0.01%) ~ and Au-added Li20-AI, 03-7SiU, photosensitive glass plate, which will serve as the insulating layer 1, is placed on an arm-t The next number is 5KL
, and make it. The above glass is melted at 1400° C. for 20 hours, the melt is poured into a mold, the ingot-shaped glass is cooled and solidified, and is cut and polished to form a glass plate having a thickness of α25 mm and a square size of 100 mm.

Next, regarding the glass plate formed above, a light-shielding mask glass in which a through-hole pattern is patterned according to each circuit layer using a separately prepared Cr-Cr0 film is placed in close contact with the photosensitive glass plate. In this state, ultraviolet rays are irradiated from above the mask glass for 5 minutes to transmit the ultraviolet rays perpendicularly to the portion of the photosensitive glass plate where the through holes are to be provided. This transparent portion is subjected to a subsequent heat treatment to form crystals that are easily soluble in low concentrations of butic acid. The exposed glass plate was placed on a quartz glass stand and heated to 530°C in the air.
, tsh is heat-treated. Subsequently, the glass plate was immersed in a 3% fluoric acid aqueous solution for 30 minutes, washed with water, and dried. In this way, a through hole with a maximum diameter of 0.15 mm, a minimum diameter Q of 0.6 mm, and a pitch α of 5 mm is formed.

Next, the entire surface of each glass plate is irradiated with ultraviolet rays for 4 minutes to perform pretreatment for crystallization in high-temperature heat treatment. Subsequently, the inside of each through hole is filled with paste by thick film screen printing to form a diamond 2, and then a necessary wiring pattern of the layered wiring 3 is patterned on the surface of each glass plate.

Here, K Ag/Pd paste is used for the input/output terminals 4 on the back surface of the bottom layer in order to increase the solder connection strength.

Further, on the surface of the uppermost layer, a pattern of the upper layer wiring 3 and a terminal 5 for connection with the thin film wiring circuit section are formed.

Subsequently, glass plates patterned with predetermined on-layer wiring 5 are laminated according to the circuit configuration, and the glass softens by mm (60 mm).
Heat to ℃). Subsequently, from the softening temperature to the crystallization treatment temperature (850° C.), pressurization and heat treatment are carried out while evacuation is under reduced pressure. As a result, an integrated glass thick film multilayer wiring circuit board is obtained. In this example, the dimensional change of the glass plate due to the heat treatment was -160±CLO4, and the thermal expansion coefficient was tIX10'/l.

(2) Production of thin film multilayer wiring circuit 'First, polyimide resin precursor face (organic diamine, silyl silyl, organic tetracarboxylic dianhydride, N-methylpyrrolidone 1
．． N-dimethylacetamide dissolved in an organic solvent and subjected to a condensation reaction) was applied with a spinner, and dried and heated (200
~360℃, 50 minutes) Curing and t-S return, thickness 50μm
A polyimide resin insulating layer 6 is formed over the entire surface of the glass thick film multilayer wiring board.

On this polyimide resin insulating layer 6, a P-cymene solution of an organosilicon polymer material was applied using a spinner, and
A 7r tresist) ffl is formed by heat treatment for 10 min. Furthermore, on the resist layer, through-holes for diamonds for connecting the thick-film multilayer wiring circuit and the thin-film multilayer wiring circuit were patterned by mask exposure, developed with a mixed solvent of isopropyl alcohol and toluene, and then patterned with isopropyl alcohol. Wash.

Next, a 20 μm square through hole is formed in the #R plasma etched polyimide resin film.

Note that the area of the polyimide resin film is 95 tm square.

Subsequently, the through hole K is formed by electroless Cu plating.
A dia 7 is formed by filling with a Cu conductor.

11 on the entire surface of the substrate by sputter deposition 1
After forming a 00 nm thick Cr film and a 350 nm thick Cu film, a photosensitive resist film was formed on the Cu film except for the areas that would become signal wiring conductors, and a 10 μm thick resist film was formed on the areas that would become signal wiring conductors.
A Cu plating pattern with a thickness of m is formed. Then, the photosensitive l
After removing the cyst film, the Cu film and Cr film under the resist film are removed by etching, and the first signal layer HI8 is formed on the polyimide resin film.

Then, again forming a polyimide resin film, forming a photoresist film, forming a through hole pattern on the photoresist film, forming a through hole in the polyimide resin film by plasma etching, filling the inside of the through hole with a conductor by electroless Cu-plating K, Formation of Cr film and Cu film by sputter deboxing, formation of photosensitive resist film except for areas that will become signal wiring conductors, electroless Cu plating, removal of photosensitive resist film, and formation of photosensitive resist film under the photosensitive resist film. The existing Cu film and Cr
The film removal process is repeated several times to form a 25-layer thin film multilayer circuit. The thickness of the nine polyimide resin thus obtained is 750 μm, and the coefficient of thermal expansion of the resin is t5) lO-7
/℃.

Note that terminals 9 for LSI chip connection, terminals 10 for continuity testing, etc. are formed on the top layer of the thin film circuit.

(3) Multilayer wiring circuit board With the above method, it is possible to manufacture a multilayer wiring circuit board on which 64 5++wa square LSI chips are mounted. The thermal expansion coefficient of this board is tIX1cr@/1: which is a large difference from the thermal expansion coefficient of the Si chip (4 x 1ff''?/℃), but this can be resolved by a connection method that absorbs the difference in thermal expansion coefficient. .

Input/output bins are also soldered to the back side of the board.

Note that the thermal expansion coefficient of polyimide resin is 2. oxNj”7
If the temperature exceeds .degree. C., the effect of preventing separation from the substrate is small.

〔Effect of the invention〕

As explained above, according to the present invention, (1) high-density and fine through-holes are formed simultaneously on the entire surface, and the dimensional change due to heat treatment is small, and the accuracy is 1.
Because of the 0x improvement, the positioning accuracy of the diamonds in thick film multilayer wiring circuits is improved, and the terminal area for bonding thin film multilayer wiring circuits can be reduced, making it possible to achieve significantly higher wiring integration than conventional sum. Can be done.

(2) Since a glass substrate with a large coefficient of thermal expansion (for example, about 11×101/°C) is used, the difference in coefficient of thermal expansion between the polyimide thin film multilayer wiring circuit and the polyimide resin thin film multilayer wiring circuit is smaller than before. Also, there is no need to peel off the resin film and the substrate due to temperature cycling, etc., further increase the number of wiring layers, or increase the number of wiring layers in the thin film multilayer wiring circuit section.
! It is possible to further expand IT.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a multilayer wiring board according to the present invention, and the second factor is a flowchart showing a manufacturing process of the multilayer wiring board according to the present invention. 1...Glass insulating layer, 2...Dia (thick film), 5...
... Layer wiring, 4... Thick film terminal for input/output, 5... Thick film leaker for thin film circuit connection, 6... Polyimide resin insulation layer, 7... Dia (Meriki), 8...・Upper layer wiring, 9・
...Picture connection terminal, 10...Other surface terminals. -, 躬 1 Roto Input/output layer "Mei J 70 Ze's hunger front face Endi 5
The 11th time of Bo I

Claims (1)

[Claims] 1. In a multilayer wiring board formed by alternately laminating wiring layers and insulating layers having wiring for electrically connecting the upper and lower wirings, the upper and lower insulating layers have thermal expansion coefficients that are different from each other. By selecting similar glass and polyimide resin, the former forms a glass thick film multilayer part, the latter forms a polyimide resin thin film multilayer part, and both are laminated. The polyimide resin thin film multilayer part is formed by laminating a glass insulating layer with thick film on each layer and interlayer wiring. A multilayer wiring board characterized in that it is formed by providing wiring and interlayer wiring and laminating them. 2. As the glass insulating layer constituting the glass thick film multilayer section, select one with a coefficient of thermal expansion of 8.0 x 10^-^7/℃ or more, and the polyimide constituting the polyimide resin thin film multilayer section. As a resin insulation layer, the thermal expansion coefficient is 2.0.
The multilayer wiring board according to claim 1, wherein the multilayer wiring board is selected to have a temperature of not more than ×10^-^6/°C. 3. In a method for manufacturing a multilayer wiring board in which wiring layers and insulating layers having wiring for electrically connecting upper and lower wirings are laminated alternately to perform multilayer wiring, a glass insulating layer having a coefficient of thermal expansion similar to that of a polyimide resin is used. After arranging a plurality of glass insulating layers and etching them through a mask to form through-holes at predetermined positions in each glass insulating layer, a thick film conductor is printed to provide wiring on the layer, and the through-holes are etched. A thick film conductor is filled to provide interlayer wiring, the above glass insulating layers are laminated and melted to form a glass thick film multilayer part, and a polyimide resin insulating layer is formed on the glass thick film multilayer part. The polyimide resin insulating layer is provided with a through hole for each resin layer to be laminated, and an on-layer wiring is provided by thin film and plating, and the through hole is made conductive to form an interlayer wiring. A method for manufacturing a multilayer wiring board, characterized by: 4. Select a glass insulating layer that has a thermal expansion coefficient of 8.0 x 10^-^7/°C or more as the glass insulating layer constituting the glass thick film multilayer part, and a polyimide constituting the polyimide resin thin film multilayer part. As a resin insulation layer, the thermal expansion coefficient is 2.0.
The method for manufacturing a multilayer wiring board according to claim 3, wherein a temperature of not more than ×10^-^6/°C is selected.