JP2009122071A - Electric test-use contactor and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the mechanical strength of a contact part, while enabling its stylus tip to be positioned accurately. <P>SOLUTION: A contactor for burn-in tests is equipped with a tabular mount part which extends vertically; a tabular arm part extending horizontally, to at least one side from the lower end of the mount part; a tabular pedestal part projecting downward from the head of the arm part; and a contact part projecting downward from the lower end of the pedestal part. The lower end of the contact part is used as the stylus tip. The mount part, the arm part and the pedestal part are made of a conductive metal material in tabular forms, and the hardness of the contact part is higher than that of the metal material of the pedestal part, or the like. The surface of at least a portion on the contact part side of the pedestal part and the surface of the contact part, except at least the stylus tip and its proximity, are covered by a film, having an optical reflection coefficient which is smaller than that of the conductive material of the pedestal part, and the like. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a contact for use in an electrical test of a flat object to be inspected such as a semiconductor integrated circuit and a method for manufacturing the contact.

  A flat test object such as a semiconductor integrated circuit is subjected to an electrical test as to whether or not it is manufactured according to specifications. This type of electrical test is an electrical connection device such as a probe card, a probe block, or a probe unit in which a plurality of probes that are individually pressed against the electrodes of an object to be inspected, that is, contacts are arranged on a substrate such as a wiring board or a probe board. It is done using. This type of electrical connection device is used to electrically connect an electrode of a device under test and an electrical circuit of a tester.

  As a contactor used in this type of electrical connection device, a plate-shaped mounting portion that is attached to the substrate so as to extend in the vertical direction, and a plate-shaped arm portion that extends from the lower end portion of the mounting portion to one side in the left-right direction. And a plate-like pedestal that protrudes downward from the tip of the arm, and a contact that protrudes downward from the lower end of the pedestal, with the lower end of the contact being the needle tip (that is, And a part to be inspected).

  In the above contact, the attachment portion, the arm portion, and the pedestal portion are formed in a plate shape from a conductive metal material to form a contact body. Such a contact is attached to the substrate at the upper end of the attachment portion and is supported in a cantilever shape. An electrical test apparatus having a large number of contacts arranged on a substrate is attached to a tester.

  In a state in which the electrical connecting device is attached to the tester, the contact is illuminated from the side of the object to be inspected by illuminating the needle tip from the side of the object to be inspected, and an area sensor such as a CCD camera images the needle tip . The obtained image signal is processed so as to perform alignment for determining the coordinate position of the needle tip by obtaining the position of the needle tip with respect to the electrode of the tester or the object to be inspected.

  On the other hand, in the case of an integrated circuit, the density of an integrated circuit to be inspected has increased, and a large number of integrated circuits are formed on one wafer, and these integrated circuits are uncut and simultaneously or divided into multiple times. Testing is being done. For this reason, it is desired to reduce the arrangement pitch of the contacts on the substrate and simultaneously increase the number of integrated circuits that can be tested.

  However, when increasing the arrangement density of the contacts on the substrate and reducing the contacts and their needle tips, not only the reflected light from the needle tips but also the reflected light from the pedestal near the needle tips enters the area sensor, The reflected light only from the needle tip cannot be identified. As a result, the conventional contact cannot accurately determine the position of the needle tip with respect to the electrode of the tester or the object to be inspected, and a correct test cannot be performed.

  In order to solve the above-described problem, a technique has been proposed in which the lower surface of the pedestal portion is inclined with respect to the vertical plane and the reflected light from the pedestal portion is prevented from entering the area sensor (Patent Document 1). However, in this contactor, the angle of the lower surface of the pedestal portion with respect to the vertical plane is insufficient to suppress the incidence of reflected light from the pedestal portion on the area sensor.

WO 2006-09544 A1

  From the above, in the conventional contact described above, the angle of the lower surface of the pedestal portion with respect to the vertical surface must be reduced in order to further suppress the reflected light from the pedestal portion entering the area sensor. However, if it does so, the connection location of a base part and a contact part will become thin, and the mechanical strength of the contact part to an electrode will be insufficient.

  An object of the present invention is to increase the mechanical strength of the contact portion even though the position of the needle tip can be accurately determined.

  An electrical test contact according to the present invention includes a plate-shaped mounting portion extending in the vertical direction, a plate-shaped arm portion extending from the lower end portion of the mounting portion to at least one side in the left-right direction, and a tip portion of the arm portion. A contactor body including a plate-like pedestal portion that protrudes downward, and a contact portion that protrudes downward from the lower end of the pedestal portion, the contact portion having the lower end of the contact portion as a needle tip.

  The attachment portion, the arm portion, and the pedestal portion are formed in a plate shape with a conductive metal material, and the hardness of the contact portion is higher than that of the metal material. The surface of at least the contact portion side of the pedestal portion and the surface of the contact portion excluding at least the needle tip and the vicinity thereof are covered with a film having a light reflectance lower than that of the conductive material.

  The film may be formed of a material having a visible light reflectance lower than that of the metal material.

  The film may be formed by at least one selected from the group including an electroplating technique, a sputtering technique, and a vapor deposition technique. The arm portion may extend from the lower end portion of the attachment portion to one side in the left-right direction.

  The method for manufacturing the contact as described above includes the following steps.

  A first photoresist layer having a first recess that imitates at least the surface of the contact main body on the side of the contact portion and at least the surface of the contact portion excluding the needle tip and its vicinity; A first step of forming a first low-reflection coating on the first recess by depositing a conductive material having a low light reflectance on the first recess.

  By depositing a metal material having a light reflectance higher than that of the first low-reflection coating, at least a portion on the contact portion side of the contact main body, and at least the portion of the contact portion excluding the needle tip and its vicinity. A second step of forming on the first low reflection coating.

  After removing the first photoresist layer, a second photoresist layer having a second recess imitating the remainder of the contactor body is formed on the base member, and a conductive material is deposited. A third step of forming the remaining part of the contact body in the second recess.

  The second photoresist layer is removed, and a third recess imitating at least the surface of the contact body on the side of the contact portion and the surface of the contact portion excluding at least the needle tip and the vicinity thereof A third photoresist layer having a point is formed on the base member, and a second low reflection film is formed in the third recess by depositing a material having a low light reflectance in the third recess. The 4th process to do.

  A fifth step of separating the contact body, the contact portion, the first low-reflection coating, and the second low-reflection coating from the base member;

  The first and second low-reflection coatings may be formed of a material having a lower reflectance with respect to visible light than the mounting portion, the arm portion, the pedestal portion, and the contact portion.

  The first and second low reflection coatings may be formed by at least one selected from the group including an electroplating technique, a sputtering technique, and a vapor deposition technique.

  The second step includes depositing a high hardness conductive material on the first low reflective coating, and the third step deposits a high tough conductive material in the second recess. Can be included. These conductive materials can be metallic materials.

  As described above, the surface of at least the contact portion side of the pedestal portion and the surface of the contact portion except at least the needle tip and the vicinity thereof are coated with a film whose light reflectance is lower than that of the material of the pedestal portion or the contact portion. When covered, the reflected light from the surface of the base portion at least on the contact portion side and at least the surface of the contact portion excluding the needle tip and the vicinity thereof are significantly reduced from entering the area sensor. As a result, the ratio of the reflected light from the needle tip to the incident light to the area sensor becomes remarkably high, and the needle tip position can be determined accurately.

  Moreover, since it is not necessary to reduce the angle of the lower surface of the pedestal portion with respect to the vertical surface unlike conventional contacts, there is no need to reduce the connection portion between the pedestal portion and the contact portion, and the mechanical strength of the connection portion is reduced. There is no need to let them.

  [Explanation of terms]

  In the present invention, in FIG. 1, the direction (vertical direction) in which the side of the electrical connection device is upward and the inspection stage side is downward is referred to as the vertical direction, and the horizontal direction orthogonal to the vertical direction is referred to as the horizontal direction. The direction of the back of the paper perpendicular to the direction is called the front-back direction.

  However, the vertical direction in the present invention differs depending on the posture of the object to be inspected at the time of inspection with respect to the tester. Therefore, the vertical direction as used in the present invention may be determined to be one of the vertical direction, the opposite direction, the horizontal direction, and the inclined direction inclined with respect to the horizontal plane, depending on the actual inspection apparatus. Good.

  [Electrical test apparatus and contactor embodiments]

  Referring to FIG. 1, an electrical test apparatus 10 is disposed in a tester (not shown) having a disk-shaped semiconductor wafer having a plurality of integrated circuits as a device under test 12. The tester inspects an electrical performance test of a plurality of uncut integrated circuits formed on the inspected object (wafer) 12 at one time or in several times. Each integrated circuit has a plurality of electrodes such as pad electrodes on the top surface.

  The electrical test apparatus 10 includes a probe card or electrical connection device 16 including a plurality of plate-like contacts 14, a chuck top 18 on which the integrated circuit 12 is disposed, and the chuck top 18 at least in the front-rear direction, the left-right direction, and It includes an inspection stage 20 that is moved three-dimensionally in the vertical direction, and an area sensor 22 such as a CCD camera disposed on the inspection stage 20 so as to photograph at least one contact 14 for current test.

  As shown in FIG. 2 to FIG. 5, each contactor 14 includes an attachment portion 24 extending in the vertical direction, an arm portion 26 extending in the left-right direction from the lower end portion of the attachment portion 24, and downward from the tip portion of the arm portion 26. A projecting plate-like pedestal portion 28 and a contact portion 30 projecting downward from the lower end of the pedestal portion 28 are included. The mounting portion 24, the arm portion 26, and the pedestal portion 28 function as a contact body in this embodiment.

  As will be described later, the contact body is made of nickel / phosphorus alloy (Ni-P), nickel / tungsten alloy (Ni-W) except for a part of the pedestal (base 44 integrated with the contact portion 32). Rhodium (Rh), phosphor bronze, nickel (Ni), palladium-cobalt alloy (Pd-Co), palladium-nickel-cobalt alloy (Pd-Ni-Co), etc. It is integrally formed in the shape of a plate having a vertical dimension.

  The contact portion 30 is made of a conductive metal material whose hardness is higher than that of the metal material that is the material of the mounting portion 24 or the like, such as rhodium or tungsten. In the illustrated example, the lower end surface of the contact portion 30 is a flat needle tip 32 perpendicular to a virtual axis extending in the vertical direction so as to be pressed by the electrode of the device under test 12.

  The surface of the contact portion 30 side of at least the contact portion 30 side of each contactor 14 and the surface of the contact portion 30 excluding at least the needle tip 32 and the vicinity thereof have a light reflectivity of the mounting portion 24, arm portion 26, pedestal. It is covered with a film 34 lower than the material of the part 28 and the contact part 30.

  The coating 34 can be formed of a glossy metal material close to black, such as zinc-nickel alloy (Ni—Zn), nickel tin alloy (Ni—Sn), black rhodium, or black ruthenium. In particular, when the material of the mounting portion 24, the arm portion 26 and the pedestal portion 28 is nickel, the reflectance of red light is about 68.6%. Material can be used.

  In the example shown in the figure, the arm portion 26 is connected to two arm regions 36 and 38 extending in the front-rear direction with an interval in the vertical direction, and two arm regions 36 and 38 are connected to each other at the front end portion and the rear end portion 2. Two connecting regions 40 and 42 are provided.

  The contact portion 30 is made of the same material as that of the base portion 44 and is integrally formed with the base portion 44 embedded in the main material of the pedestal portion 28. The base portion 44 functions as a part of the pedestal portion 28.

  The contact portion 30 includes a base portion 46 having a truncated pyramid shape when viewed from the front-rear direction and manufactured integrally with the base portion 44. For this reason, each surface of the contact part 30 in the left-right direction is inclined with respect to a virtual axis extending in the up-down direction.

  The needle tip 32 is a lower surface of a columnar tip portion 48 that is manufactured integrally with the base portion 46. However, the needle tip 32 may be a surface inclined with respect to a virtual axis extending in the up-down direction, or may be a sharp needle tip such as a pyramidal or conical tip. The members forming the base portion 44, the base portion 46, and the columnar portion 48 are bent into a crank shape.

  Each contactor 14 has a cantilever shape by a conductive bonding material such as soldering on a flat conductive portion (for example, a connection land) formed on the lower surface of the electrical connection device 16 on the upper surface of the mounting portion 24. Attached to.

  The electrical connection device 16 includes a wiring substrate 50 made of an electrically insulating material such as glass-filled epoxy, a ceramic substrate 52 attached to the lower surface of the wiring substrate 50, and a probe substrate attached to the lower surface of the ceramic substrate 52. 54 and a reinforcing plate 56 attached to the upper surface of the wiring board 50.

  The chuck top 18 holds the integrated circuit 12 in a vacuum and keeps it immovable. The inspection stage 20 is a three-dimensional movement mechanism that moves the chuck top 18 in three directions, the front-rear direction, the left-right direction, and the up-down direction, and rotates angularly around an axis that extends the chuck top 18 in the up-down direction. A θ moving mechanism is provided.

  As shown in FIG. 1, the area sensor 22 focuses the light beam 58 and directs it toward the needle tip 32 of the specific contact 14 to illuminate the needle tip 32 and the vicinity thereof, and from the needle tip 32 and the vicinity thereof. The reflected light is received and converted into an electrical signal. The output signal of the area sensor 22 is supplied to an image processing apparatus that determines the coordinate position of a specific contact 14, particularly the needle tip 32.

  In the electrical test apparatus 10, the light beam 58 applied to the specific contact 32 from below is reflected on the needle tip 32 of the contact portion 30 and the lower surface of the pedestal portion 28.

  However, the contactor 14 has a light reflectivity at least on the surface of the pedestal portion 28 on the contact portion 30 side and at least the surface of the contact portion 32 excluding the needle tip 32 and the vicinity thereof. Therefore, the amount of reflected light traveling toward the area sensor 22 from the lower surfaces of the pedestal portion 28 and the base portion 46 is significantly smaller than the amount of reflected light from the needle tip 32. For this reason, the position of the needle tip 32 of the specific contactor 14 can be determined accurately.

  According to the experiment, in the contactor 14, the image obtained by processing the output signal of the area sensor 22 only showed the image 60 of the needle tip 32 clearly as shown in FIG.

  On the other hand, in the conventional contact, the image 64 obtained by processing the output signal of the area sensor 22 clearly shows the image 64 of the root 46 near the image 62 of the needle tip 32 as shown in FIG. In addition, an image (not shown) of the lower surface of the pedestal portion 28 appeared around the image 62.

  According to the contact 14 described above, unlike the conventional contact, it is not necessary to significantly reduce the angle of the lower surface of the pedestal portion 28 with respect to the vertical surface. There is no need to make it thinner, and there is no need to reduce the mechanical strength of the connection location.

  [Example of manufacturing method]

  An example of a method for manufacturing the contact 14 having the structure shown in FIGS. 2 to 5 will be described with reference to FIGS.

  First, as shown in FIG. 6A, a plate-like base member 70 made of stainless steel is prepared.

  Next, as shown in FIG. 6B, a photoresist layer 72 is formed on the upper surface of the base member 70 by coating or the like.

  Next, as shown in FIG. 6C, the photoresist layer 72 is exposed in a state where a portion thereof is masked, the photoresist layer 72 is developed, and a recess 74 is formed in the photoresist layer 72. The

  Next, as shown in FIG. 6D, a sacrificial layer 76 is formed in the recess 74 by an electroplating technique, a sputtering technique, a vapor deposition technique, or the like.

  Next, as shown in FIG. 6E, the photoresist layer 72 is removed, and instead, a photoresist layer 78 is formed on one surface of the base member 70 and the sacrificial layer 76 by coating or the like.

  Next, as shown in FIG. 6F, the photoresist layer 78 is exposed in a state in which a part thereof is masked, the photoresist layer 78 is developed, and a plane of a part of the film 34 is formed on the photoresist layer 78. A recess 80 having a planar shape corresponding to the shape is formed by photolithography. The recess 80 has a planar shape imitating at least the surface of the contact main body on the side of the contact portion 30 and at least the surface of the contact portion 30 excluding the needle tip 32 and the vicinity thereof.

  Next, as shown in FIG. 7A, the first low-reflection film 82 made of a material whose light reflectance is lower than that of the mounting portion 24, the arm portion 26, the pedestal portion 28, and the contact portion 30 is formed in the recess 80. Formed by deposition.

  Next, as shown in FIG. 7B, the crank-shaped member 84 that defines the base portion 44, the base portion 46, and the columnar portion 48 is formed on the first low reflection coating 82 by deposition.

  Both the first low-reflection coating 82 and the member 84 can be formed by a deposition technique such as an electroplating technique, a sputtering technique, or a vapor deposition technique. The base portion 44, the base portion 46, and the columnar portion 48 are integrated as a member 84. The base 44 acts as a part of the pedestal 28 as described above.

  Next, as shown in FIG. 7C, the photoresist layer 78 is removed, and instead, a photoresist layer 86 is formed on the base member 70, the sacrificial layer 76, and the member 84 by coating or the like.

  Next, as shown in FIG. 7D, exposure is performed with the photoresist layer 86 partially masked, the photoresist layer 86 is developed, and contact including the mounting portion 24, the arm portion 26, and the pedestal 28 is performed. A recess 88 having a planar shape corresponding to the planar shape of the child body is formed in the photoresist layer.

  Next, as shown in FIG. 7E, a member 90 that defines the mounting portion 24, the arm portion 26, and the rest of the pedestal 28 is formed in the recess 88 by electroplating technology, sputtering technology, vapor deposition technology, or the like. Is done.

  Next, as shown in FIG. 7F, the photoresist layer 86 is removed. Instead, a photoresist layer 92 is applied on the upper surface of the base member 70, the sacrificial layer 76, the member 84, and the member 90 by coating or the like. It is formed.

  Next, as shown in FIG. 8A, the photoresist layer 92 is exposed with a portion thereof masked, the photoresist layer 92 is developed, and a recess 94 is formed in the photoresist layer 92. . The recess 94 has a planar shape imitating at least the surface of the portion of the contact body on the side of the contact portion 30 and the surface of the contact portion 30 excluding at least the needle tip 32 and the vicinity thereof.

  Next, as shown in FIG. 8B, a second low-reflection film 96 made of a material whose light reflectance is lower than that of the mounting portion 24, the arm portion 26, the pedestal portion 28, and the contact portion 30 is formed in the recess 94. Thus, the exposed portion of the member 84 and the member 90 is formed. The second low reflection coating 96 can also be formed by a deposition technique such as an electroplating technique, a sputtering technique, or a vapor deposition technique.

  As a result, at least the surface of the pedestal portion 28 on the side of the contact portion 30 and the surface of the contact portion 30 excluding at least the needle tip 32 and the vicinity thereof are lower in light reflection than the conductive material that is the material of the pedestal portion 28 and the like. A contact 14 covered with a rate coating is produced.

  Next, as shown in FIG. 8C, the photoresist layer 92 is removed to expose the contacts 14, and the sacrificial layer 76 is removed by etching or the like.

  Next, as shown in FIG. 8D, the contact 14 formed on the base member 70 is removed from the base member 70.

  [Other Embodiments of Contact]

  As shown in FIG. 11, the contact 14 has a bifurcated shape by providing another base portion 44 a that extends from the base portion 44 of the contact portion 30 and extends downward in parallel to the base portion 44 at a distance from the base portion 44 in the front-rear direction. Both base portions 44 and 44 a may be embedded in the main material of the pedestal portion 28. In this case, part of both side surfaces of the main material of the pedestal portion 28 may be sandwiched between the bifurcated base portions 44 and 44a.

  The present invention can be used not only for an energization test of an uncut integrated circuit formed on a semiconductor wafer, but also for an energization test of a cut integrated circuit.

  The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

It is a front view which shows one Example of the electrical test apparatus using the contactor which concerns on this invention. It is a front view which shows one Example of the contactor which concerns on this invention. It is a front view which expands and shows the contact part vicinity of the contactor shown in FIG. FIG. 4 is a left side view of FIG. 3. FIG. 4 is a bottom view of FIG. 3. It is process drawing which shows one Example of the manufacturing method of the contactor shown in FIGS. It is a figure for demonstrating the process following FIG. It is a figure for demonstrating the process following FIG. It is a figure which shows one Example of the image acquired by image | photographing the contactor which concerns on this invention from the needle tip side with an area sensor. It is a figure which shows one Example of the image obtained by image | photographing the conventional contactor from the needle-tip side with an area sensor. FIG. 5 is a side view similar to FIG. 4, showing another embodiment of the contact according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electrical test apparatus 12 Inspected object 14 Contact 24 Attachment part 26 Arm part 28 Base part 30 Contact part 32 Needle tip 34 Coating 70 Substrate 72, 78, 86, 92 Photoresist 74, 80, 88, 94 Recess 76 Sacrificial layer 82,96 1st and 2nd light low reflection film 84,90 member

Claims (8)

A plate-shaped mounting portion extending in the vertical direction, a plate-shaped arm portion extending from the lower end portion of the mounting portion to at least one side in the left-right direction, and a plate-shaped pedestal portion protruding downward from the distal end portion of the arm portion. A contact body, and a contact portion protruding downward from the lower end of the pedestal portion, the contact portion having the lower end of the contact portion as a needle tip,
The mounting portion, the arm portion, and the pedestal portion are formed in a plate shape with a conductive metal material,
The hardness of the contact portion is higher than that of the metal material,
The surface of at least the contact portion side of the pedestal portion and the surface of the contact portion excluding at least the needle tip and the vicinity thereof are covered with a film having a light reflectance lower than that of the conductive material. Test contact.   The contact for electrical testing according to claim 1, wherein the film is made of a material having a visible light reflectance lower than that of the metal material.   The electrical test contact according to claim 1, wherein the coating is formed by at least one selected from the group including an electroplating technique, a sputtering technique, and a vapor deposition technique.   The contact for an electrical test according to claim 1, wherein the arm portion extends from a lower end portion of the attachment portion to one side in the left-right direction. A method of manufacturing a contactor comprising a contactor body and a contact part protruding from the contactor body and having a tip as a needle tip,
Based on a first photoresist layer having a first recess imitating at least the surface of the contact main body on the side of the contact portion and at least the surface of the contact portion excluding the needle tip and the vicinity thereof Forming a first low reflection coating on the first recess by depositing a material having a low light reflectance on the first recess; and
By depositing a conductive material having a light reflectance higher than that of the first low-reflection coating, at least a portion on the contact portion side of the contact body, and at least the portion of the contact portion excluding the needle tip and the vicinity thereof. A second step of forming on the first low reflection coating;
After removing the first photoresist layer, a second photoresist layer having a second recess imitating the remainder of the contactor body is formed on the base member, and a conductive material is deposited. A third step of forming the remainder of the contactor body in the second recess;
The second photoresist layer is removed, and a third recess imitating at least the surface of the contact body on the side of the contact portion and the surface of the contact portion excluding at least the needle tip and the vicinity thereof A third photoresist layer having a point is formed on the base member, and a second low reflection film is formed in the third recess by depositing a material having a low light reflectance in the third recess. A fourth step of
And a fifth step of separating the contact main body, the contact portion, the first low-reflection coating and the second low-reflection coating from the base member.   The manufacturing method according to claim 5, wherein the first and second low-reflection coatings are formed of a material having a lower reflectance with respect to visible light than the attachment portion, the arm portion, the pedestal portion, and the contact portion. .   The manufacturing method according to claim 5, wherein the first and second low reflection coatings are formed by at least one selected from the group including an electroplating technique, a sputtering technique, and a vapor deposition technique.   The second step includes depositing a high hardness conductive material on the first low reflective coating, and the third step deposits a high tough conductive material in the second recess. The manufacturing method according to claim 5, further comprising:

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