JP3330532B2 - Probe card for wafer batch type measurement and inspection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a probe card for wafer type measurement / inspection performed on a wafer provided with an optical element such as a light receiving element.

[0002]

2. Description of the Related Art In recent years, electronic devices equipped with a semiconductor integrated circuit device (hereinafter, referred to as a "semiconductor device") have been remarkably reduced in size and price, and accordingly, the size of the semiconductor device has been reduced. Also, demands for lower prices are increasing.

In general, a semiconductor device is supplied after a semiconductor chip and a lead frame are electrically connected to each other by bonding wires, and then the semiconductor chip and the lead frame are supplied in a state of being sealed with resin or ceramics, and mounted on a printed circuit board. Is done. However, due to the demand for miniaturization of electronic equipment, a method of directly mounting a semiconductor device in a state of being cut out from a semiconductor wafer (hereinafter, the semiconductor device in this state is referred to as a bare chip) on a circuit board has been developed. It is desired to supply guaranteed bare chips at a low price.

In order to guarantee the quality of bare chips, it is necessary to inspect semiconductor devices such as burn-in in a wafer state. However, since it takes a lot of time to perform one or several separate inspections on a plurality of bare chips formed on a semiconductor wafer many times, it is realistic in terms of time and cost. is not. Therefore, it is required to perform inspection such as burn-in on all bare chips in a wafer state at once.

In order to inspect a bare chip collectively in a wafer state, a power supply voltage and a signal are simultaneously applied to electrodes of a plurality of semiconductor chips formed on a semiconductor wafer,
It is necessary to operate the plurality of semiconductor chips. For this purpose, it is necessary to prepare a probe card having a very large number of probe needles (usually several thousand or more). To do so, a conventional needle type probe card has a problem in terms of the number of pins. Also can not respond in terms of price.

Therefore, there has been proposed a probe card capable of collectively contacting probe electrodes with a large number of pad electrodes on a wafer (Japanese Patent Application Laid-Open No. Hei 7-231019). According to this technique, a large number of bumps are formed on a probe card, and these bumps are used as probe electrodes.

[0007]

However, according to the above probe card, it is difficult to collectively measure and inspect the wafer on which the light receiving elements are formed. When trying to irradiate the wafer with light from the outside, since many probe electrodes and multilayer wiring are formed on the probe card, reflection or blocking of light in unpredictable directions occurs.
Therefore, it becomes difficult to appropriately irradiate light of a desired intensity to a specific region of the wafer on which the light receiving element is formed,
Accurate measurement and inspection cannot be performed.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a probe card capable of performing a wafer type measurement / inspection even on a wafer on which a light receiving element and the like are formed. Is to do.

[0009]

A thin film provided with a plurality of two-dimensionally arranged probe electrodes and a multilayer wiring board facing the thin film and electrically connected to the plurality of probe electrodes are provided. a wafer-level measuring probe card for testing with the said thin film is arranged light emitting elements in the gap between the multilayer wiring board, and the light emitting element the multilayer interconnection
It is formed on the surface of the substrate facing the wafer side .

[0010] Another probe card of the present invention includes a thin film provided with a plurality of probe electrodes arranged two-dimensionally,
A wafer batch-type measurement / inspection probe card comprising a multilayer wiring board facing the thin film and electrically connected to the plurality of probe electrodes, wherein a light receiving element is provided in a gap between the thin film and the multilayer wiring board. Is disposed , and the light receiving element
Is formed on the surface of the multilayer wiring board facing the wafer side.
Have been.

[0011]

[0012]

[0013]

[0014]

[0015]

Still another probe card according to the present invention is a secondary probe card.
A plurality of probe electrodes originally arranged and the plurality of probes
A multi-layer wiring board electrically connected to the lobe electrode.
Wafer probe for batch measurement and inspection
The multilayer wiring board is formed from a light-transmitting substrate,
A light shielding film is formed on both surfaces of the multilayer wiring board, and the light shielding film
Has an opening in the area facing the predetermined area of the wafer to be inspected.
Having a portion, light incident from the side surface of the multilayer wiring board,
The light propagates in the space between the light shielding films in the lateral direction, and
The inspection target wafer is irradiated from the mouth .

[0017]

[0018]

[0019]

[0020]

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an outline of a wafer batch type measurement / inspection technique using a probe card according to the present invention will be described.

FIG. 1 shows a probe card 1 which can collectively contact a large number of pad electrodes on a wafer with probe electrodes. A wafer (for example, a silicon wafer having a diameter of 200 mm) on which elements and circuits to be measured and inspected are formed is placed on a wafer tray 3 as it is without being divided into chips.
During measurement and inspection, the wafer 2 is sandwiched between the probe card 1 and the wafer tray 3. A small space formed between the probe card 1 and the wafer tray 3 is sealed from the atmosphere by a seal ring 4. The space is depressurized through the vacuum valve 5 (for example, 200
The pressure is reduced to about millitorr), so that the probe card 1 uniformly presses the wafer 2 by applying the force of the atmospheric pressure. As a result, the probe electrodes of the probe card 1 can press the pad electrodes on the wafer 2 with a uniform force over the entire surface of the wide wafer 2. In order to ensure that a large number of probe electrodes on the probe card 1 make contact with predetermined pad electrodes on the wafer 2, it is necessary to perform alignment between the probe card 1 and the wafer 2 with high accuracy before the contact. There is.

According to such a wafer batch type measurement / inspection technique, a large number of pad electrodes formed on the probe card 1 can be formed on a large number of thousands to tens of thousands of pad electrodes formed on the entire surface of the wafer 2. The probe electrodes can be simultaneously and reliably contacted.

Hereinafter, embodiments of the probe card according to the present invention will be described.

FIG. 2 shows a cross-sectional structure of the probe card 20 according to the first embodiment of the present invention. The probe card 20 includes a multilayer wiring board 21 to be electrically connected to a measurement / inspection device, a polyimide thin film 22 with bumps, and a localized anisotropic conductive rubber 23 provided therebetween. At least. The localized anisotropic conductive rubber 23 is an elastic member that electrically connects the electrode wiring 21b of the multilayer wiring board 21 and the bump 22b of the polyimide thin film 22 with bump. FIG. 2 shows a state in which the three members 21 to 23 are separated in the vertical direction. One probe card 20 is formed by tightly fixing these members 21 to 23 (see FIG. 2). (See FIG. 3).

As the multilayer wiring board 21, the glass substrate 2
1a in which a multilayer wiring 21b is formed can be used. The glass substrate 21a is preferable because a glass substrate having high flatness over a wide area can be relatively easily manufactured. In addition, since the thermal expansion coefficient of glass is close to the thermal expansion coefficient of a silicon wafer, glass is particularly suitable as a material for a multilayer wiring board of a burn-in probe card.

The formation of the multilayer wiring 21b can be performed by using a known thin film deposition technique and a known patterning technique. For example, if a conductive thin film such as copper (Cu) is deposited on a glass substrate 21a by a sputtering method or the like and then the conductive thin film is patterned by a photolithography and etching process, a wiring 21b having an arbitrary pattern is formed. be able to. Different levels of wiring 21b are
1c. The interlayer insulating film 21c is formed, for example, by coating a polyimide thin film on the glass substrate 2 by a method such as spin coating.
It is obtained by forming on 1a. The multilayer wiring 21b is
A large number of bumps (probe electrodes) 22b two-dimensionally arranged in a plane are electrically connected to connection electrodes and connectors (not shown) provided in a peripheral area of the probe card 20, and an external inspection device or inspection circuit is provided. And the probe electrode 22b.

The probe card 20 of this embodiment is characterized in that a light emitting element 29 is provided on a multilayer wiring board 21. This light emitting element 29 is preferably a semiconductor light emitting element separately formed on a compound semiconductor substrate. Although the light emitting element 29 of this embodiment is a light emitting diode (LED), a surface emitting semiconductor laser or the like may be used instead of the LED. Such a light emitting element 29 is provided on the multilayer wiring board 21.
A plurality of the wirings are arranged at appropriate upper positions, and are electrically connected to predetermined wirings of the multilayer wiring board 21. The mounting of the light emitting element 29 is preferably performed in a bare chip state. It is not necessary to assign one light emitting element to each chip before being cut out from the wafer. This is because the light emitted from the light emitting diodes spreads in the horizontal direction, so that each light emitting element 29 can irradiate a relatively large area on the wafer with light.

The bumped polyimide thin film 22 is obtained, for example, as follows. First, a large number of openings (inner diameter of 10 to 20 μm) are formed in a base material in which a polyimide thin film 22 a having a thickness of about 18 μm and a copper thin film having a thickness of about 35 μm are formed in two layers.
Degree). Each opening is filled with a metal material such as Ni by using a method such as electrolytic plating to form the bump 22b. If unnecessary portions of the copper thin film are removed from the polyimide thin film 22a by etching, the bumped polyimide thin film 22 as shown is obtained. The height of the bump 22b is
As an example, it is about 20 μm. The lateral size of the bump is about 50 μm. Polyimide thin film 22a
The position of the bump 22b to be formed is determined depending on the position of the pad electrode 26 formed on the wafer 25 to be measured.

In the localized type anisotropic conductive rubber 23, conductive particles 23b are arranged at specific locations in a silicone rubber sheet (about 200 μm thick) 23a, and the conductive particles 23b are located at those locations. ) In a chain. By interposing elastic rubber between the multilayer wiring board 21 and the bumps 22b, the bumps 22b of the probe card 20 and the wafer 25 are not affected by the steps on the wafer 25 and the warpage of the wafer 25. The contact with the upper electrode 26 can be reliably realized. The localized type anisotropic conductive rubber 23 is not provided in a region where the light emitting element 29 is arranged.

When such a probe card 20 is used for burn-in inspection, the coefficient of thermal expansion of the polyimide thin film 22a (about 16 × 10 ⁻⁶ / ° C.) and the coefficient of thermal expansion of the wafer 25 (about 3 × 10 ⁻⁶ / ° C.) ), The bump 22b on the polyimide thin film 22a during heating for burn-in.
Is shifted laterally with respect to the position of the pad electrode 26 on the wafer 25. This displacement is greater in the peripheral portion than in the central portion of the wafer 25, and normal electrical contact between the wafer 25 and the probe card 20 cannot be obtained. To solve such a problem, Japanese Patent Laid-Open No. 7-2
As disclosed in Japanese Patent Publication No. 31019, it is effective to attach a polyimide thin film 22a to a rigid ring (not shown) such as a ceramic ring having a thermal expansion coefficient close to that of a silicon wafer, and to apply a tension to the polyimide thin film 22a in advance. It is. In this case, it is better to form the bump 22b after attaching the polyimide thin film 22a to the rigid ring. This is because the position of the bump 22b is not easily shifted.

The wafer 25 is placed on a wafer tray 28. After the alignment process is performed so that the wafer tray 28 on which the wafer 25 is mounted is located at an appropriate position with respect to the probe card 20, the distance between the probe card 20 and the wafer tray 28 is reduced. As a result, the wafer 25
Upper pad electrode 26 and bump 22 of probe card 20
b makes physical contact. As described above, by reducing the pressure in the sealed space between the probe card 20 and the wafer tray 28, each bump 22b presses the pad electrode 26 on the wafer 25 with a substantially uniform force. Thereafter, an electric signal and a power supply voltage from a drive circuit and an inspection circuit (not shown) are supplied to the pad electrodes 26 on the wafer 25 via the bumps 22 of the probe card 20. In the case of the burn-in inspection, the probe card 20, the wafer 25, and the wafer tray 28 are integrally inserted into the burn-in device and heated in a state as shown in FIG.

According to the probe card 20 of this embodiment, light can be emitted from the light emitting element 29 to the light receiving section 27 of the wafer 25 at the time of measurement and inspection. Wafer 25
When a device having a light receiving unit 27 (for example, a CCD image pickup device) is formed, it is necessary to appropriately irradiate the light receiving unit 27 with light in an appropriate wavelength band during measurement and inspection such as burn-in. As in the present embodiment, the light emitting element 29
Are integrally mounted on the probe card 20, measurement and inspection can be easily performed.

The probe card 20, the wafer 25, and the wafer tray 28 are maintained in a state as shown in FIG. 3 before and after the inspection / measurement. These members integrally hold the wafer without detaching from the probe card 20 in the wafer tray 28 in which the above-mentioned closed space is in a reduced pressure state.

When the wafer type inspection / measurement is completed,
The pressure in the closed space formed between the probe card 20 and the tray 28 is increased to restore the pressure to about atmospheric pressure. As a result, the tray 28 is separated from the probe card 20, and the wafer 25 is taken out from the inside.

As described above, according to the probe card of the present embodiment, even the wafer on which the light receiving portion 27 is formed can be used.
Collective measurement and inspection can be performed.

If it is desired to carry out collective measurement / inspection on the wafer on which the light emitting element is formed, the light emitting element 2
Instead of 9, a probe card provided with a light receiving element may be used. Further, the light receiving element and the light emitting element may be arranged at different positions on one probe card 20.

Instead of forming the light emitting element 29 and the light receiving element on the surface of the glass substrate 21a facing the wafer,
As shown in FIG. 4, these may be formed on the back surface of the glass substrate 21a. In this case, in addition to the advantage that the back surface of the glass substrate 21a can be effectively used, the advantage that the restriction on the element size of the light emitting element or the like is greatly eased is also produced. When the light emitting element 29 is formed on the surface of the glass substrate 21a facing the wafer, the height of the light emitting element 29 needs to be within the space between the polyimide thin film 22 with bumps and the glass substrate 21a. When it is arranged on the back surface of the glass substrate 21a, there is no such restriction at all. However, in order to realize the arrangement shown in FIG. 4, it is necessary to form a wiring for driving the light emitting element 29 (or the light receiving element) on the back surface of the glass substrate 21a.
Such a wiring can be formed by using an ordinary thin film deposition technique or lithography technique.

In the embodiment shown in FIGS. 2 and 3, a glass substrate is used as the base material of the multilayer wiring board 21 of the probe card 20, but another insulating substrate, for example, a ceramic multilayer substrate is used instead of the glass substrate. May be used. However, needless to say, in the embodiment shown in FIG. 4, it is necessary to use a light-transmitting substrate.

Next, still another embodiment of the probe card according to the present invention will be described with reference to FIG. In addition,
5, the members corresponding to the members shown in FIG. 3 are given the same reference numerals, and the description of the members will not be repeated here.

The feature of the probe card 20 shown in FIG. 5 is that light shielding films 40a and 40b are provided on both surfaces of the glass substrate 21a. The light-shielding films 40a and 40b can be formed by depositing a metal thin film of, for example, aluminum or the like on the order of several 100 nm. An opening 4 is provided in a region of the light-shielding film 40b facing the light receiving unit 27 of the wafer to be measured and inspected.
1 is provided. As a result, when light enters from the side surface of the glass substrate 21a as shown in FIG. 5, the light propagates in the space between the light shielding films 40a and 40b in the horizontal direction, and passes through the opening 41 of the light shielding film 40b. Then, the light receiving section 27 of the wafer 25 arranged oppositely is selectively irradiated. Unnecessary light is not irradiated on a region other than the region to be irradiated with light on the wafer.

Thus, according to the present embodiment, collective measurement / inspection of a light receiving element wafer can be performed with a simpler configuration without providing a light emitting element on a probe card as in the above-described embodiment.

Next, still another embodiment of the probe card according to the present invention will be described with reference to FIG.

The probe card of this embodiment has basically the same configuration as that of the above-described embodiment described with reference to FIG. 5, but the light-shielding film 40 is formed on the surface of the glass substrate 21a on the wafer side. It is only provided above. As a result, as shown in FIG. 6, when light is incident from the upper surface side of the glass substrate 21a, the light passes only through the opening 41 of the light shielding film 40, and the light on the wafer 25 disposed opposite to the opening 41 The light receiving section 27 is selectively irradiated.

According to this embodiment, light irradiation can be performed more uniformly over the entire surface of the wafer than in the above-described embodiment.

In the above embodiments, the wiring layer on the multilayer parallel wiring board and the bumps are electrically connected by using the localized anisotropic conductive rubber 23. However, the localized anisotropic conductive rubber 23 is used. The wiring layer and the bump may be directly contacted without using the conductive rubber 23. Conversely, if bumps are formed on the wafer to be measured, there is no need to form bumps on the probe card side. In such a case, by directly pressing the tip of the localized anisotropic conductive rubber 23 of the probe card to the bump on the wafer, the wafer batch type measurement / inspection can be executed. Further, the wiring layer of the multilayer wiring board may be directly contacted with the bump on the wafer without using the localized anisotropic conductive rubber 23.

[0047]

According to the probe card of the present invention, since the probe card itself has the light emitting element, it is possible to carry out the wafer batch type inspection and measurement even on the wafer on which the light receiving element is formed. Therefore, the inspection and measurement of the circuit including the light receiving element can be performed at the wafer level without dividing the wafer into chips, and the time required for the inspection and measurement can be significantly reduced. As a result, cost reduction of the semiconductor device is achieved.

According to another probe card of the present invention, since the probe card itself has the light receiving element, it is possible to perform the wafer batch type inspection measurement even on the wafer on which the light emitting element is formed. For this reason, the inspection and measurement of the circuit including the light emitting element can be performed at the wafer level without dividing the wafer into chips, and the time required for the inspection and measurement can be significantly reduced. As a result, cost reduction of the semiconductor device is achieved.

When the probe electrode is a bump electrode, it is easy to reliably contact the probe electrode with the electrode on the wafer. Also, there is no need to form bump electrodes on the wafer.

If a conductive rubber for electrically connecting the probe electrode to the wiring on the multilayer wiring board is provided between the probe electrode and the multilayer wiring board, the elasticity of the conductive rubber may cause the wafer to be damaged. The difference between the upper steps is absorbed, and reliable contact is achieved over the entire surface of the wafer.

If the probe electrode is formed on a thin film stretched with tension on the rigid ring, the difference in thermal expansion coefficient between the wafer and the thin film in measurement and inspection at a temperature higher than room temperature, such as burn-in. The displacement of the bump position due to the influence of is prevented. As a result, reliable contact between the probe card and the wafer can be achieved even at a temperature different from the normal temperature.

The probe electrode may be formed from at least a part of a wiring layer on the multilayer wiring board. When bump electrodes are formed on the wafer side, it is not necessary to provide bump electrodes on the probe card side, and the structure can be simplified by using the electrodes on the multilayer wiring board as probe electrodes as they are.

When the light emitting element and the light receiving element are arranged on the surface of the multilayer wiring board on which the probe electrodes are arranged,
There is an advantage that light can be emitted from a position near the light receiving portion of the wafer to be measured.

When the multilayer wiring board is formed from a translucent substrate and the light emitting element and the light receiving element are arranged on the back side of the multilayer wiring board, the back side of the multilayer wiring board can be used effectively, and the light emitting element and the light receiving element to be mounted can be used. Greater freedom for size.

According to still another probe card of the present invention, a light-shielding film is formed on both sides of a light-transmitting multilayer wiring board, and the light-shielding film is formed in an area opposed to a predetermined area of a wafer to be inspected. Since the light emitting element has the opening, it is possible to irradiate a predetermined region of the wafer with light propagated in the substrate without providing the light emitting element on the multilayer wiring substrate. For this reason,
It becomes possible to perform a wafer batch type measurement inspection on a wafer on which a light receiving element is formed.

[Brief description of the drawings]

FIG. 1 is a perspective view for explaining a wafer batch type measurement / inspection technique.

FIG. 2 is a sectional view showing a configuration of a probe card and the like according to the embodiment.

FIG. 3 shows a probe card of the present embodiment at the time of measurement,
Sectional drawing which shows the relationship between a wafer and a wafer tray.

FIG. 4 is a sectional view showing another embodiment of the probe card according to the present invention.

FIG. 5 is a sectional view showing still another embodiment of the probe card according to the present invention.

FIG. 6 is a sectional view showing still another embodiment of the probe card according to the present invention.

DESCRIPTION OF SYMBOLS 1 Probe card 2 Wafer (for example, a silicon wafer with a diameter of 200 mm) 3 Wafer tray 4 Seal ring 5 Vacuum valve 20 Probe card 21 Multilayer wiring board 21a Glass substrate 21b Electrode wiring 21c Interlayer insulating film 22 Bumped polyimide thin film 22a Polyimide Thin film 22b Bump 23 Localized anisotropic conductive rubber 25 Wafer 26 Pad electrode 27 Light receiving portion in wafer 28 Wafer tray 29 Light receiving element 40a Light shielding film 40b Light shielding film 41 Opening provided in light shielding film

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-214750 (JP, A) JP-A-7-231019 (JP, A) JP-A-7-201945 (JP, A) JP-A-2- 54948 (JP, A) JP-A-9-5391 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01R 1/06-1/073 G01R 31/26 H01L 21/64- 21/66

Claims (3)

(57) [Claims] 1. A wafer package comprising: a thin film provided with a plurality of two-dimensionally arranged probe electrodes; and a multilayer wiring board facing the thin film and electrically connected to the plurality of probe electrodes. A probe card for mold measurement inspection, wherein a light emitting element is disposed in a gap between the thin film and the multilayer wiring board , and the light emitting element is on a wafer side of the multilayer wiring board.
A probe card formed on a surface facing the probe card. 2. A wafer package comprising: a thin film provided with a plurality of two-dimensionally arranged probe electrodes; and a multilayer wiring board facing the thin film and electrically connected to the plurality of probe electrodes. A probe card for mold measurement inspection, wherein a light receiving element is disposed in a gap between the thin film and the multilayer wiring board , and the light receiving element is on a wafer side of the multilayer wiring board.
A probe card formed on a surface facing the probe card. 3. A plurality of probe electrodes arranged two-dimensionally.
And a plurality of electrodes electrically connected to the plurality of probe electrodes.
Wafer batch type measurement / inspection probe with multilayer wiring board
Card The multilayer wiring board is formed from a light-transmitting substrate, Light shielding films are formed on both surfaces of the multilayer wiring board, The light-shielding film has a region facing a predetermined region of the wafer to be inspected.
Having an opening in the area, The light incident from the side of the multilayer wiring board is
Propagates laterally in the space between the
Irradiating a wafer to be inspected.
Bucard.