JP2003017159A - Manufacturing method of thin film sheet with bumps, and thin film sheet with bumps - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a manufacturing method of a thin film sheet with bumps which can easily make the height of respective bumps uniform, and to improve the yield of a thin film sheet with bumps for a card-shaped probe. SOLUTION: The manufacturing method of a thin film sheet with bumps includes a process of forming a plurality of concave parts 38 penetrating to a first conduction layer 32 by irradiating laser beam from a second conduction layer 34 side against a three layer structure 36 composed of the first conduction layer 32, a thin film sheet 24 and the second conduction layer 34; a process of forming a plated metal layer 40 which electrically connects the first conduction layer 32 exposed at respective concave parts 38 and the second conduction layer 34 by applying a plating to the second conduction layer 34 side; a process of forming resists 48a, 48b corresponding to respective concave parts 38 on the surfaces of the first conduction layer 32 and the second conduction layer 34; a process of forming a plurality of bump top end parts 27 protruding from the surface of the thin film sheet 24 by applying etching treatment to the surface of the first conduction layer 32; and a process of forming a plurality of bump rear end parts 28 which are electrically connected to bump top end parts 27 respectively and insulated from each other, by applying etching treatment to the second conduction layer 34 side.

Description

Detailed Description of the Invention

[001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thin film sheet with bumps, and more particularly to a thin film sheet having a large number of bumps for electrically connecting to a large number of electrode pads formed on the surface of a silicon wafer or the like. Manufacturing method.

[002]

2. Description of the Related Art In a semiconductor manufacturing process, it is extremely important to check an integrated circuit formed on a silicon substrate at each stage and eliminate defective products in advance. Therefore, starting from a function test that simply checks that each integrated circuit is functioning, a burn-in test that accelerates and extracts potential defects by applying temperature and voltage, high-speed probe inspection, etc. Inspection (test) is being carried out. Conventionally, these tests
Except for basic inspection such as "/ W (Good chip / Wafer) check", most of them are processed into dice (cutting out from silicon wafer), mounting, bonding, resin encapsulation, lead molding, etc. It was carried out, so it was inefficient.

On the other hand, recently, it has been attempted to carry out various inspections collectively or separately for all integrated circuits formed on a silicon wafer before cutting individual integrated circuits. In order to realize this so-called wafer level test, a probe is brought into contact with a large number of electrode pads (20,000 to 80,000 pins) formed on a silicon wafer, and an electric signal from the tester is surely applied. Required to do. Various probe structures have been proposed to realize this, and among them, the most prominent one is the type shown in FIG.

This card-type probe 70 is composed of a wiring board 16 having a conductive pattern 14 laminated on the surface of an insulating substrate 12 such as ceramic or glass, and a localized anisotropic conductive rubber provided with a plurality of conductive particle portions 18. It has a laminated structure of a plate 20 and a thin film sheet 72 with bumps. The conductive pattern 14 of the wiring board 16,
The conductive particle portions 18 of the anisotropic conductive rubber plate 20 and the bumps 74 of the bumped thin film sheet 72 are electrically connected to each other.

When the probe 70 is used to inspect the silicon wafer 29, first, the tip portions of the bumps 74 functioning as the probes are arranged to face the electrode pads 30 on the silicon wafer 29, and then the silicon wafer 29 is placed. And probe
Vacuum suction between 70. As a result, the tips of the bumps 74 come into pressure contact with the electrode pads 30, and the electric signal applied through the conductive pattern 14 is supplied to the electrode pads 30 via the conductive particle portions 18 and the bumps 74. Instead of such a vacuum pressure bonding method, a mechanical pressure bonding method can also be used to form bumps 74 and electrode pads.
The contact state between 30 can be secured.

By using the probe 70 having such a structure, inspection signals can be collectively applied to a large number of electrode pads 30 formed on the surface of the silicon wafer 29, and at the same time, output signals can be output to the outside. Since it can be taken out, it becomes possible to efficiently perform various inspections at a stage before being cut out as individual integrated circuits.

The thin film sheet with bumps 72, which is a main constituent member of the probe 70, has conventionally been formed through the steps shown in FIGS. 34 to 39. First, a two-layer structure 80 in which a conductive layer 78 of copper or the like is formed on one surface of a thin film sheet 76 made of polyimide or the like having flexibility and insulation is prepared (FIG. 3).
4).

Next, the surface of the thin film sheet 76 is irradiated with a laser to form a recess 82 (non-through hole) (FIG. 35). A resist 84 is formed in a predetermined pattern on the surface of the thin film sheet 76 and the surface of the conductive layer 78 (see FIG. 3).
6).

Next, the thin film sheet 76 side is subjected to a plating treatment to deposit a required amount of metal such as nickel on the surface of the conductive layer 78 exposed on the bottom surface of the recessed portion 82, thereby forming the thin film sheet 76.
A bump 74 having a tip protruding from the surface of the is formed (FIG. 37). Similarly, the conductive layer 78 side is also plated,
Metal layer 86 such as nickel on the part not covered with resist
Is formed.

Next, after removing the resist 84 (see FIG.
8), the conductive layer 78 connecting between the bumps 74 is partially removed by etching (FIG. 39), and the bumps 74 are removed.
Insulation between them is secured.

[0011]

In order to perform the wafer level test by the probe 70, all the bumps must be formed.
74 and the electrode pad 30 must be in firm contact,
For that purpose, it is required that the height (projection amount) of the tip of each bump 74 (portion protruding from the surface of the thin film sheet 76) be uniform. This is because if there is variation in the height between the tips of the bumps 74, the lower bumps 74 cannot contact the electrode pads 30. However, as long as the above-described conventional manufacturing method is used, it is extremely difficult to control the protrusion amount of the bump 74 with high accuracy because the metal deposition state is affected by the current density distribution and the liquid flow in the plating process.

The present invention has been devised in order to solve the above problems of the conventional method for manufacturing a thin film sheet with bumps, and a manufacturing method capable of easily making the height of each bump uniform. By realizing the above, it is intended to improve the yield of the thin film sheet with bumps.

[0013]

In order to achieve the above object, a first method for manufacturing a thin film sheet with bumps according to the present invention comprises a first conductive layer, a thin film sheet having flexibility and insulation, And a step of forming a plurality of recesses that reach the first conductive layer from the second conductive layer in the laminated structure including the second conductive layer, and plating treatment on the second conductive layer side. And a step of forming a plated metal layer for electrically connecting the first conductive layer and the second conductive layer exposed in each recess, and each recess on the surface of the first conductive layer and the plated metal layer. And forming a resist corresponding to
Etching the conductive layer side and removing the portion not covered with the resist to form a plurality of bump tips protruding from the surface of the thin film sheet, and the second conductive layer side etching treatment. By removing at least the plated metal layer and the second conductive layer in the portion not covered with the resist, a plurality of bump rear end portions electrically connected to the bump front end portions and insulated from each other are provided. And a step of forming.

According to this manufacturing method, individual bump tips are formed by etching the first conductive layer, and the height (the amount of protrusion from the surface of the thin film sheet) of the first conductive layer is different from that of the first conductive layer. Specified by thickness. Therefore, if the thickness of the first conductive layer is made uniform in advance,
The height of each formed bump can be easily controlled. Specifically, the variation in the height of the individual bump tips is ± 10% of the reference bump height.
It becomes possible to suppress below.

As the first conductive layer, stainless steel,
A thin metal film such as nickel is applicable. The second conductive layer is made of, for example, a copper thin film. The thin film sheet having flexibility and insulation is made of, for example, polyimide, liquid crystal polymer, epoxy or polyimide resin impregnated aramid nonwoven fabric. The plated metal layer is formed by nickel plating or copper plating, for example. After this plating treatment, it is desirable to perform a polishing treatment on the surface of the plated metal layer to ensure smoothness and adjust the thickness. The recess is formed, for example, by irradiating the surface of the second conductive layer with a laser to partially remove the second conductive layer and the thin film sheet. Alternatively, a plurality of openings reaching the thin film sheet are formed on the surface of the second conductive layer to form a conformal mask, and the surface of the conformal mask is irradiated with laser to expose the thin film in each opening. The recess may be formed by removing the sheet.

A second method of manufacturing a thin film sheet with bumps according to the present invention is a method for manufacturing a laminated structure including a thin film sheet having flexibility and insulation and a conductive layer. From the step of forming a plurality of recesses reaching the conductive layer, a step of forming a conductive thin film or a catalyst layer on the surface of the thin film sheet and the inner surface of each recess, the thin film sheet side is subjected to a plating treatment, the conductive thin film Alternatively, a step of forming a plated metal layer covering the catalyst layer, a step of forming a resist corresponding to each recess on the surface of the conductive layer and the plated metal layer, and an etching treatment on the conductive layer side, The step of forming a plurality of bump tips protruding from the surface of the thin film sheet by removing the uncovered portion, and the plating metal layer side are subjected to an etching treatment, By removing at least the plated metal layer and the conductive thin film or the catalyst layer in the portion not covered with the bumps, a plurality of bump rear ends electrically connected to the above bump front end and insulated from each other are formed. It has a forming process.

According to this manufacturing method, individual bump tips are formed through the etching process on the conductive layer, and the height (protrusion amount) thereof is defined by the thickness of the conductive layer. Therefore, if the thickness of the conductive layer is made uniform in advance, the height of each formed bump can be easily controlled.

The conductive layer is made of metal such as stainless steel or nickel. The thin film sheet having flexibility and insulation is made of, for example, polyimide, liquid crystal polymer, epoxy or polyimide resin impregnated aramid nonwoven fabric. The conductive thin film is, for example, a sputtered film or a deposited film of nickel, rhodium, palladium, chromium, or the like, and is adopted when the plated metal layer is formed by electroplating. The catalyst layer is made of palladium, for example, and is adopted when the plating metal layer is formed by electroless plating. The plated metal layer is formed by nickel plating or copper plating, for example. Also in this case, it is desirable to perform a polishing treatment on the surface of the plated metal layer after the plating treatment to secure the smoothness and adjust the thickness. The recess is formed, for example, by irradiating the surface of the thin film sheet with a laser and partially removing the laser.

A third method of manufacturing a thin film sheet with bumps according to the present invention is a method for electrically conducting a laminated structure including a flexible and insulating thin film sheet and a conductive layer from the surface of the thin film sheet. A step of forming a plurality of recesses reaching the layer, a step of forming a conductive thin film or a catalyst layer on the surface of the thin film sheet and the inner surface of each recess, and a plating treatment on the conductive layer side to provide a necessary thickness. A step of forming a first plated metal layer, a step of performing a plating treatment on the thin film sheet side to form a second plated metal layer covering the conductive thin film or the catalyst layer, and the first plated metal Forming a resist corresponding to each recess on the surface of the layer and the second plated metal layer, and performing etching treatment on the first plated metal layer side to form a first portion of the portion not covered with the resist. Plated metal And a step of forming a plurality of bump tips protruding from the surface of the thin film sheet by removing the conductive layer, and at least a portion not covered with a resist by performing an etching process on the second plated metal layer side. And removing the second plated metal layer and the conductive thin film or the catalyst layer to form a plurality of bump rear ends that are electrically connected to the bump tips and are insulated from each other. There is.

According to this manufacturing method, the tip of each bump is formed through the etching process on the first plated metal layer and the conductive layer, and the height (protruding amount) of the first plated metal layer and the conductive layer is adjusted. It is defined by the thickness of the conductive layer. Therefore, the height of each bump can be controlled by making the thickness of the conductive layer uniform in advance and making the thickness of the first plated metal layer uniform. Since the first plated metal layer is formed over the entire surface of the conductive layer, it can be said that it is easier to control the total thickness as compared with the conventional method of individually growing the plated metal for each bump. It is also easy to make the entire thickness uniform through a polishing process after forming the plated metal layer.

The conductive layer is made of a metal such as stainless steel or nickel. The thin film sheet having flexibility and insulation is made of, for example, polyimide, liquid crystal polymer, epoxy or polyimide resin impregnated aramid nonwoven fabric. The conductive thin film is, for example, a sputtered film or a deposited film of nickel, rhodium, palladium, chromium, or the like, and is adopted when the plated metal layer is formed by electroplating. The catalyst layer is made of palladium, for example, and is adopted when the plating metal layer is formed by electroless plating. The plated metal layer is formed by nickel plating or copper plating, for example. Also in this case, it is desirable to perform a polishing treatment on the surface of the plated metal layer after the plating treatment to secure the smoothness and adjust the thickness. The recess is formed, for example, by irradiating the surface of the thin film sheet with a laser and partially removing the laser.

The thin film sheet with bumps according to the present invention is
A thin film sheet having a flexible and insulating layer, a plurality of bump tip portions arranged on one surface side of the thin film sheet, and a plurality of bump rear end portions arranged on the other surface side of the thin film sheet, In a thin film sheet with bumps in which the front end of each bump and the rear end of each bump penetrate through the thin film sheet and are electrically connected, the variation in height between the front ends of the bumps is ± 10%.
It is characterized by the following.

[0023]

1 is a partial cross-sectional view showing a card type probe 10 according to the present invention, which is a wiring board 16 having a conductive pattern 14 laminated on the surface of an insulating substrate 12 such as ceramic or glass. A laminated structure of a localized anisotropically conductive rubber plate 20 having a plurality of conductive particle portions 18 and a bumped thin film sheet 22 is provided. The bumped thin film sheet 22 is a thin film sheet 24 made of polyimide or the like having flexibility and insulation.
And a plurality of bumps 26 arranged so as to penetrate the thin film sheet 24. Each bump 26 is a thin film sheet.
Conductive tip 27 protruding from one side of 24 and thin film sheet
And a conductive rear end portion 28 that penetrates through 24 and is taken out to the other surface side. The front end portion 27 and the rear end portion 28 of each bump are electrically connected. Conductive pattern 14 on wiring board 16
And the conductive particle portion 18 of the anisotropic conductive rubber plate 20 and the bump 26.
The spaces are electrically connected to each other.

Using this probe 10, a silicon wafer 29
When performing the inspection on (1), similarly to the above, the bump tip portion 27 is arranged to face the electrode pad 30 on the silicon wafer 29, and then the silicon wafer 29 and the probe 10 are vacuum-sucked. As a result, the bump tip portion 27 is pressed against each electrode pad 30, and the electric signal from the tester is supplied to the electrode pad 30 via the conductive pattern 14, the conductive particle portion 18, and the bump 26. The contact state between the bumps 26 and the electrode pads 30 can be secured by a mechanical pressure welding method instead of the vacuum pressure welding method.

The first method of manufacturing the thin film sheet 22 with bumps will be described below with reference to FIGS. First, as shown in FIG. 2, a first conductive layer 32 (thickness: 10 to 100 μm) made of stainless steel or nickel, a thin film sheet 24 (thickness: 10 to 50 μm), and a second conductive layer made of copper or the like. A three-layer structure 36 including the conductive layer 34 (thickness: 5 to 35 μm) is prepared. The surface of the first conductive layer 32 is roughened in advance by blasting or the like.

Next, as shown in FIG. 3, the second conductive layer
The surface of 34 is irradiated with a laser beam (for example, a YAG third harmonic laser) in a predetermined pattern to partially remove the second conductive layer 34 and the thin film sheet 24. As a result, a plurality of recesses (non-through holes) 38 reaching the first conductive layer 32 are formed. Here, if necessary, a burr processing step on the periphery of the recess and a desmearing step on the inner surface of the recess are performed.

Next, as shown in FIG. 4, after the plating resist layer 37 is formed on the surface of the conductive layer 32, the second conductive layer 34 is formed.
The inner surface of the recess 38 and the second conductive layer are plated.
A plated metal layer 40 made of nickel or the like is formed on the surface of 34. At this time, the plated metal deposited in the recess 38 and the first conductive layer 32 are electrically connected. Prior to this plating process, the recess 38 is formed by means such as vapor deposition or sputtering.
A conductive film may be deposited on the inner surface of the. After the plated metal layer 40 is formed, the surface thereof is subjected to polishing treatment such as CMP (chemical mechanical polishing) or lapping to adjust the surface smoothness and thickness. Next, as shown in FIG. 5, a gold plating layer 42 is formed on the surface of the plating metal layer 40. The gold plating layer 42 is formed for the purpose of reducing the contact resistance with the conductive particle portion 18 of the anisotropically conductive rubber plate 20, and even if gold is deposited using a technique such as vapor deposition or sputtering. Good. Further, a metal other than gold (for example, rhodium, palladium, etc.) may be deposited on the surface of the plated metal layer 40 by a method such as plating, vapor deposition, and sputtering (the same applies hereinafter).

Next, after removing the plating resist layer 37, as shown in FIG. 6, photoresist layers 44a and 44b are formed on the surfaces of the first conductive layer 32 and the gold plating layer 42, respectively.
Is formed. As shown in FIG. 7, photomasks 46a and 46b having a light transmitting portion of a predetermined pattern are arranged on the surfaces of the photoresist layers 44a and 44b, and ultraviolet rays are irradiated. Thereafter, the photoresist layers 44a and 44b are subjected to a development process, so that the exposed portions are left by the exposure process and the circular or rectangular resists 48a and 48b are formed into the concave portions 38 as shown in FIG. Is formed at a position corresponding to. The resists 48a and 48b are heat-treated at a predetermined temperature. The photoresists 44a, 44
As b, instead of using the negative type in which the photosensitive portion remains as described above, a positive type in which the photosensitive portion is removed may be adopted (the same applies hereinafter).

Next, a predetermined etching treatment is applied to the first conductive layer 32 side, and as shown in FIG.
The part not covered with a is removed. As a result, a large number of truncated cone-shaped or truncated pyramid-shaped bump tips 27 having the relatively sharp edges 27a project from the surface of the thin film sheet 24. Further, the gold plating layer 42 side is also subjected to a predetermined etching treatment to remove the gold plating layer 42, the plating metal layer 40, and the second conductive layer 34 in the portions not covered with the resist 48b, as shown in FIG. To do. As a result, a large number of bump rear end portions 28 insulated from each other are formed. The bump front end portion 27 and the bump rear end portion 28 are electrically connected, and the bump 26 is formed by both. Finally, by removing the resists 48a and 48b covering the bump front end portion 27 and the rear end portion 28, the bumped thin film sheet 22 is completed. The end surface 27b of the bump tip 27 is subjected to surface roughening treatment such as etching, if necessary.

According to this manufacturing method, the height of the tip portion 27 of each bump 26 is previously defined as the thickness of the first conductive layer 32, and the plating metal is grown for each bump as in the conventional case. Since it is different from the method of ensuring a predetermined height, the amount of protrusion of the bump tip portion 27 can be easily controlled.

The electrode pad 30 formed on the silicon wafer 29 is generally made of aluminum,
An oxide film (alumina) is formed on the surface. Therefore, at the time of inspection, it is required that the tip end portion 27 of the bump pierces the oxide film and surely contacts the electrode pad 30. On the other hand, the bump tip portion 27 obtained by the above manufacturing method has a roughened end surface 27b and a sharp edge portion.
Since 27a is provided, the surface oxide film of the electrode pad 30 can be easily crushed.

As a method of forming the concave portion 38, as shown in FIGS.
As shown in FIG. 5, a so-called conformal mask method can also be used. In this case, first, as shown in FIG. 11, a photoresist layer 50 is formed on the surface of the second conductive layer 34, and a photomask 52 having a light transmitting portion having a predetermined pattern is arranged on the surface thereof.

Next, an exposure process and a development process are performed on the surface of the photomask 52, and a resist 54 is formed on the surface of the second conductive layer 34, as shown in FIG.
Here, an etching process is performed on the second conductive layer 34 side to remove a portion of the second conductive layer 34 which is not covered with the resist 54, thereby opening the thin film sheet 24 as shown in FIG. Many parts 56 are formed. After that, the resist 54 is removed to complete the conformal mask 57 as shown in FIG.

When the surface of the conformal mask 57 is irradiated with a laser beam such as an excimer, as shown in FIG. 15, the thin film sheet 24 exposed in the opening 56 is partially removed, and a recess communicating with the opening 56 is formed. 58 is formed. After that,
By following the steps of FIGS. 4 to 10, the thin film sheet 22 with bumps is completed.

In addition, the second procedure is performed in the same manner as in FIGS.
After forming the opening 56 by etching the conductive layer 34 of
Instead of using the laser beam, the recess 58 is formed by partially removing the thin film sheet 24 by chemical etching or plasma etching using a chemical such as hydrazine.
Can also be formed (not shown).

A second method of manufacturing the bumped thin film sheet 22 will be described below with reference to FIGS.
First, as shown in FIG. 16, a conductive layer 32 (thickness: 10 to 100 μm) made of stainless steel or nickel, and a thin film sheet 2
4 (thickness: 10 to 50 μm) is prepared. The surface of the conductive layer 32 is roughened in advance by blasting or the like.

Next, as shown in FIG. 17, a thin film sheet
The thin film sheet 24 is partially removed by irradiating the surface of 24 with a laser beam (YAG third harmonic laser) in a predetermined pattern. As a result, a plurality of recesses (non-through holes) 60 reaching the conductive layer 32 are formed. Here, if necessary, a burr processing step on the periphery of the recess and a desmearing step on the inner surface of the recess are performed.

Next, as shown in FIG. 18, a thin film sheet
A sputtering process is performed on the 24 side to form a sputtered film 61 made of nickel or the like. As a result, the surface of the thin film sheet 24 and the inner surface of the recess 60 (including the exposed surface of the conductive layer 32) are
Covered by sputtered film 61. Next, as shown in FIG. 19, after forming a plating resist layer 62 on the surface of the conductive layer 32, a plating process is performed on the thin film sheet 24 side to cover the inner surface of the recess 60 and the surface of the thin film sheet 24 with the sputtered film 61. above,
A plated metal layer 63 made of nickel or the like is formed. At this time, the plated metal deposited in the recess 60 and the conductive layer 32 are electrically connected via the sputtered film 61. Plated metal layer
After forming 63, the surface is subjected to a predetermined polishing treatment to adjust the surface smoothness and thickness. As shown in FIG.
A gold plating layer 42 is further formed on the surface of the plating metal layer 63.

Next, after removing the plating resist layer 62, as shown in FIG. 21, photoresist layers 44a and 44b are formed on the surfaces of the first conductive layer 32 and the gold plating layer 42, respectively.
Is formed. On the surface of each photoresist layer 44a, 44b, a photomask 46a provided with a light transmitting portion of a predetermined pattern,
46b is arranged and is irradiated with ultraviolet rays. After that, by developing the photoresist layers 44a and 44b, as shown in FIG. 22, the portions exposed by the above exposure process are left, and the circular or rectangular resists 48a and 48b are left.
b is formed at a position corresponding to each recess 60. The resists 48a and 48b are heat-treated at a predetermined temperature.

Next, the conductive layer 32 side is subjected to a predetermined etching treatment to remove the portion not covered with the resist 48a, as shown in FIG. As a result, a large number of truncated cone-shaped or truncated pyramid-shaped bump tips 27 having the relatively sharp edges 27a project from the surface of the thin film sheet 24. Further, the gold plating layer 42 side is also subjected to a predetermined etching treatment to remove the gold plating layer 42, the plating metal layer 63, and the sputter film 61 in the portions not covered with the resist 48b. This results in bump rear ends 28 that are isolated from each other.
Are formed in plural. The bump front end portion 27 and the bump rear end portion 28 are electrically connected, and the bump 26 is formed by both. Finally, by removing the resists 48a and 48b covering the bump front end portion 27 and the rear end portion 28, the bumped thin film sheet 22 is completed. An end surface 27b of the bump tip portion 27 is subjected to surface roughening treatment such as etching, if necessary.

According to this manufacturing method, the height of the tip end portion 27 of each bump 26 is previously defined as the thickness of the conductive layer 32, and the plating metal is grown for each bump as in the conventional case, and the predetermined height is obtained. Since it is different from the method to secure the
The amount of protrusion of 27 can be easily made uniform.

A third method of manufacturing the thin film sheet 22 with bumps will be described below with reference to FIGS. First, as shown in FIG. 24, the thin film sheet 24 (thickness: 10 to 50
A two-layer structure 65 is prepared by depositing a conductive layer 64 (thickness: 5 to 35 μm) made of copper, stainless steel, nickel or the like on the surface of (μm).

Next, as shown in FIG. 25, a thin film sheet
The thin film sheet 24 is partially removed by irradiating the surface of 24 with a laser beam (eg, YAG third harmonic laser) in a predetermined pattern. As a result, a plurality of recesses (non-through holes) 60 reaching the metal thin film are formed. Here, if necessary, a burr processing step on the periphery of the recess and a desmearing step on the inner surface of the recess are performed.

Next, as shown in FIG. 26, a thin film sheet
A sputtering process is performed on the 24 side to form a sputtered film 61 made of nickel or the like. Next, as shown in FIG. 27, the conductive layer 64 side is plated to form a first plated metal layer 66 of nickel or the like with a predetermined thickness. Further, the thin film sheet 24 side is also plated to form a second plated metal layer 67 of nickel or the like on the sputtered film 61 covering the inner surface of the recess 60 and the surface of the thin film sheet 24. At this time, the plating metal deposited in the recess 60 and the conductive layer 64,
It is electrically connected via the sputtered film 61. After forming the first plated metal layer 66 and the second plated metal layer 67, the respective surfaces are subjected to a predetermined polishing treatment to adjust the smoothness and thickness of the surfaces. As shown in FIG. 28, a gold plating layer 42 is formed on the surface of the second plating metal layer 67.

Next, as shown in FIG. 29, photoresist layers 44a and 44b are formed on the surface of the first plated metal layer 66 and the surface of the gold plated layer 42. Each photoresist layer
Photomasks 46a and 46b each having a light transmitting portion having a predetermined pattern are arranged on the surfaces of 44a and 44b, and are irradiated with ultraviolet rays. Thereafter, by performing a developing process on each of the photoresist layers 44a and 44b, as shown in FIG. 30, the portions exposed by the above exposure process are left, and the circular or rectangular resists 48a and 48b are formed into the concave portions 60. Is formed at a position corresponding to. The resists 48a and 48b are heat-treated at a predetermined temperature.

Next, the first plating metal layer 66 side is subjected to a predetermined etching treatment, and as shown in FIG. 31, a portion of the first plating metal layer which is not covered with the resist 48a.
66 and the conductive layer 64 are removed. As a result, a large number of truncated cone-shaped or truncated pyramid-shaped bump tips 27 having the relatively sharp edges 27a project from the surface of the thin film sheet 24. Further, the gold plating layer 42 side is also subjected to a predetermined etching treatment so that the gold plating layer 42, the second plating metal layer 67, and the sputter film 61 which are not covered with the resist 48b are formed.
To remove. As a result, the back ends of the bumps are
Many 28 are formed. Finally, by removing the resists 48a and 48b covering the bump front end portion 27 and the rear end portion 28,
The bumped thin film sheet 22 is completed. An end surface 27b of the bump tip portion 27 is subjected to surface roughening treatment such as etching, if necessary.

According to this manufacturing method, the height of the tip portion 27 of each bump 26 is determined by the thickness of the conductive layer 64 plus the thickness of the first plated metal layer 66. Since the first plated metal layer 66 is formed over the entire surface of the conductive layer 64, it is easier to control the total thickness as compared with the conventional method of individually growing the plated metal for each bump. The final protrusion amount of the bump tip portion 27 can be easily made uniform.

As described above, the photoresists 44a, 44b
Instead of forming the resists 48a and 48b by subjecting the resists to an exposure process and a development process (see FIGS. 7, 21, and 29), an excimer laser is used as the photoresists 44a, 44.
A resist having a required size and shape may be formed by irradiating b with a predetermined pattern.

Further, as shown in FIGS. 5, 20, and 28, in the above, the gold plating layer 42 is formed on the surfaces of the plating metal layers 40, 63, 67 at a relatively early stage, and bumps are formed. The example of partially removing the gold plating layer 42 together with the plating metal layers 40, 63, 67 through the etching process in the process of forming the rear end portion 28 has been described (see FIGS. 10, 23 and 31).
It is also possible to form the gold plating layer 42 after forming the bump rear end portion 28. FIG. 32 shows an example of the thin film sheet 22 after forming a thin film sheet 22 with bumps having a bump front end portion 27 and a rear end portion 28 according to the first manufacturing method.
Electrode thin film for plating 68 that covers the tip 27 of each bump on the surface of 24
Are formed. The electrode thin film 68 for plating is composed of a sputtered film or a deposited film of copper or the like. Next, a gold plating layer 42 is formed on the bump rear end 28 side by electroplating. Finally, the plating electrode thin film 68 is removed. Alternatively, although not shown, each bump rear end portion 28
After forming a resist covering the surface of the thin film sheet 24 between,
The resist may be peeled off after the gold plating layers 42 are formed on the surfaces of the bump rear ends 28 by electroless plating, respectively.

The thin film sheet with bumps 22 obtained by the above manufacturing method is a probe for wafer level test.
The use is not limited to 10 and can be applied to, for example, a probe for checking pixels in a liquid crystal panel.

[0051]

According to the first method of manufacturing a thin film sheet with bumps according to the present invention, the bump tips protruding from the surface of the thin film sheet are formed through the etching treatment on the first conductive layer. The amount of protrusion at the tip of each bump is defined by the thickness of the first conductive layer. Therefore, by making the thickness of the first conductive layer uniform in advance, it becomes possible to easily control the amount of protrusion of each bump tip formed.

According to the second method for manufacturing a thin film sheet with bumps according to the present invention, the tip of the bump protruding from the surface of the thin film sheet is formed by etching the conductive layer. It will be defined by the layer thickness. Therefore, by making the thickness of the conductive layer uniform in advance, it is possible to easily control the protrusion amount of each bump tip.

According to the third method of manufacturing a thin film sheet with bumps according to the present invention, the tip of the bump protruding from the surface of the thin film sheet is formed through the etching treatment on the first plated metal layer and the conductive layer. The protrusion amount is defined by the thicknesses of the first plated metal layer and the conductive layer. Therefore, by making the thickness of the conductive layer uniform in advance and making the thickness of the first plated metal layer uniform, it is possible to easily control the protrusion amount of each bump tip. Become.

According to the thin film sheet with bumps of the present invention, the variation in height between the tip portions of the bumps is suppressed to ± 10% or less. If a card-type probe is constructed by combining it with a plate, it becomes possible to surely bring all the bump tips into contact with the electrode pads on the silicon wafer.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing an example of a card type probe according to the present invention.

FIG. 2 is a partial cross-sectional view showing a first manufacturing process of a thin film sheet with bumps which is a constituent member of the card type probe.

FIG. 3 is a partial cross-sectional view showing a first manufacturing process of a thin film sheet with bumps.

FIG. 4 is a partial cross-sectional view showing a first manufacturing process of a thin film sheet with bumps.

FIG. 5 is a partial cross-sectional view showing a first manufacturing process of a bumped thin film sheet.

FIG. 6 is a partial cross-sectional view showing a first manufacturing process of a bumped thin film sheet.

FIG. 7 is a partial cross-sectional view showing a first manufacturing process of a bumped thin film sheet.

FIG. 8 is a partial cross-sectional view showing a first manufacturing process of a bumped thin film sheet.

FIG. 9 is a partial cross-sectional view showing a first manufacturing process of a bumped thin film sheet.

FIG. 10 is a partial cross-sectional view showing a first manufacturing process of a bumped thin film sheet.

FIG. 11 is a partial cross-sectional view showing the process of forming a conformal mask.

FIG. 12 is a partial cross-sectional view showing the process of forming a conformal mask.

FIG. 13 is a partial cross-sectional view showing the process of forming a conformal mask.

FIG. 14 is a partial cross-sectional view showing the process of forming a conformal mask.

FIG. 15 is a partial cross-sectional view showing the process of forming a conformal mask.

FIG. 16 is a partial cross-sectional view showing the second manufacturing process of the bumped thin film sheet.

FIG. 17 is a partial cross-sectional view showing the second manufacturing process of the bumped thin film sheet.

FIG. 18 is a partial cross-sectional view showing the second manufacturing process of the thin film sheet with bumps.

FIG. 19 is a partial cross-sectional view showing a second manufacturing step of a thin film sheet with bumps.

FIG. 20 is a partial cross-sectional view showing a second manufacturing step of a bumped thin film sheet.

FIG. 21 is a partial cross-sectional view showing a second manufacturing step of a bumped thin film sheet.

FIG. 22 is a partial cross-sectional view showing the second manufacturing step of the bumped thin film sheet.

FIG. 23 is a partial cross-sectional view showing the second manufacturing process of the bumped thin film sheet.

FIG. 24 is a partial cross-sectional view showing the third manufacturing process of the thin film sheet with bumps.

FIG. 25 is a partial cross-sectional view showing the third manufacturing process of the bumped thin film sheet.

FIG. 26 is a partial cross-sectional view showing the third manufacturing step of the bumped thin film sheet.

FIG. 27 is a partial cross-sectional view showing a third manufacturing step of a thin film sheet with bumps.

FIG. 28 is a partial cross-sectional view showing the third manufacturing process of a bumped thin film sheet.

FIG. 29 is a partial cross-sectional view showing the third manufacturing process of a thin film sheet with bumps.

FIG. 30 is a partial cross-sectional view showing the third manufacturing process of the thin film sheet with bumps.

FIG. 31 is a partial cross-sectional view showing the third manufacturing process of a thin film sheet with bumps.

FIG. 32 is a partial cross-sectional view showing a modified example of the first manufacturing process of the thin film sheet with bumps.

FIG. 33 is a partial cross-sectional view showing an example of a conventional card type probe.

FIG. 34 is a partial cross-sectional view showing a conventional manufacturing process of a thin film sheet with bumps.

FIG. 35 is a partial cross-sectional view showing a conventional manufacturing process of a bumped thin film sheet.

FIG. 36 is a partial cross-sectional view showing a conventional manufacturing process of a thin film sheet with bumps.

FIG. 37 is a partial cross-sectional view showing a conventional manufacturing process of a thin film sheet with bumps.

FIG. 38 is a partial cross-sectional view showing a conventional manufacturing process of a thin film sheet with bumps.

FIG. 39 is a partial cross-sectional view showing a conventional manufacturing process of a thin film sheet with bumps.

[Explanation of symbols]

10 card type probe 12 Insulation board 14 Conductive pattern 16 wiring board 18 Conductive particle part 20 Localized anisotropic conductive rubber plate 22 Thin film sheet with bumps 24 thin film sheet 26 bumps 27 Tip of bump 27a Edge part 27b End face 28 Rear end of bump 29 Silicon wafer 30 electrode pad 32 First conductive layer 34 Second conductive layer 36 three-layer structure 37 Plating resist layer 38 recess 40 plated metal layer 42 gold plated layer 44a, 44b Photoresist layer 46a, 46b Photomask 48a, 48b resist 50 photoresist layer 52 photo mask 54 Resist 57 Conformal mask 59 two-layer structure 60 recess 61 Sputtered film 62 Plating resist layer 63 plated metal layer 64 Conductive layer 65 two-layer structure 66 First plated metal layer 67 Second plated metal layer 68 Electrode thin film for plating

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masatoshi Kashiwagi             32 Mitsui Chemicals, 580 Nagaura, Sodegaura City, Chiba Prefecture             Within the corporation (72) Inventor Moriji Moriji             32 Mitsui Chemicals, 580 Nagaura, Sodegaura City, Chiba Prefecture             Within the corporation F-term (reference) 2G011 AA10 AA11 AB06 AB08 AC14                       AE03 AF07                 4M106 AA01 BA01 BA14 CA56 CA70                       DD03 DD09 DD10 DD15

Claims (6)

[Claims] 1. A laminated structure including a first conductive layer, a flexible and insulating thin film sheet, and a second conductive layer, wherein A step of forming a plurality of recesses that reach the layer, and a plating process in which the second conductive layer side is plated to electrically connect the first conductive layer and the second conductive layer exposed in each recess A step of forming a metal layer; a step of forming a resist corresponding to each recess on the surfaces of the first conductive layer and the plated metal layer; and a step of etching the first conductive layer side and coating the resist with the resist. The step of forming a plurality of bump tips protruding from the surface of the thin film sheet by removing the uncovered portion, and the plating metal layer of the portion not covered with the resist by etching the second conductive layer side. And by removing the second conductive layer And a step of forming a plurality of bump rear end portions electrically connected to the bump front end portions and insulated from each other. 2. A conformal mask is formed by forming a plurality of openings reaching the thin film sheet on the surface of the second conductive layer, and irradiating the surface of the conformal mask with laser to form each opening. The method for manufacturing a thin film sheet with bumps according to claim 1, wherein the recess is formed by removing the exposed thin film sheet. 3. A thin film sheet having flexibility and insulating properties,
A step of forming a plurality of recesses that reach the conductive layer from the surface of the thin film sheet in a laminated structure including a conductive layer, and forming a conductive thin film or a catalyst layer on the surface of the thin film sheet and the inner surface of each recess And a step of performing a plating treatment on the thin film sheet side to form a plated metal layer covering the conductive thin film or the catalyst layer, and a resist corresponding to each recess on the surface of the conductive layer and the plated metal layer. The step of forming each of them, the step of forming a plurality of bump tips protruding from the surface of the thin film sheet by etching the conductive layer side and removing the portion not covered with resist, and the plating metal The bump tip portion is formed by etching the layer side and removing the plated metal layer and the conductive thin film or the catalyst layer which are not covered with the resist. Are electrically connected, the manufacturing method of the bumps thin sheet and forming mutually plurality of bumps rear end which is insulated. 4. A thin film sheet having flexibility and insulation,
A step of forming a plurality of recesses that reach the conductive layer from the surface of the thin film sheet in a laminated structure including a conductive layer, and forming a conductive thin film or a catalyst layer on the surface of the thin film sheet and the inner surface of each recess And a step of forming a first plated metal layer having a required thickness by plating the conductive layer side, and performing a plating process on the thin film sheet side to form the conductive thin film or catalyst layer. A step of forming a second plated metal layer covering the surface of the first plated metal layer and a step of forming a resist corresponding to each recess on the surfaces of the first plated metal layer and the second plated metal layer, and the first plating A step of forming a plurality of bump tips protruding from the surface of the thin film sheet by performing etching treatment on the metal layer side and removing the first plated metal layer and the conductive layer which are not covered with the resist; The second plating metal layer side is subjected to an etching treatment to remove the second plating metal layer and the conductive thin film or the catalyst layer which are not covered with the resist, thereby electrically connecting to the bump tip portion. And a step of forming a plurality of bump rear ends that are insulated from each other. 5. The method for producing a thin film sheet with bumps according to claim 1, wherein the recesses are formed by laser irradiation. 6. A thin film sheet having a flexible and insulating layer,
The thin film sheet includes a plurality of bump tip portions arranged on one surface side and a plurality of bump rear end portions arranged on the other surface side of the thin film sheet, and each bump tip portion and each bump rear end portion are In the thin film sheet with bumps that penetrates through the thin film sheet and is electrically connected, the variation in height between the tip portions of the bumps is ± 10% or less.