JPH01303733A - Probe device - Google Patents

Abstract

PURPOSE:To prevent any leakage current from being set up by a method wherein the holding surface opposite to a specimen of a holder mounting the specimen is composed of an insulating member. CONSTITUTION:A specimen 6 is mounted on a holder (ceramic) 33 wherein a fluid is circulated to set up the previously specified temperature for measuring the electric properties of the specimen 6. Then, the holding surface 33a opposite to the specimen 6 of the holder 33 is composed of an insulating member. Consequently, the specimen 5 held by the holder 33 is interrupted from the fluid circulating in the holder 33 to be electrically insulated from the holder 33. Through these procedures, even if specimen electrodes 22 are impressed with measuring signal current, any leakage current from the rear side of the specimen 6 can be minimized.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field)　゛ The present invention relates to a probe device.

(Prior Art) As is well known, semiconductor-related elements are widely used in various industrial fields. In particular, there are an increasing number of devices that are used under various environmental temperatures ranging from low temperature ranges to high temperature ranges. Accordingly, in the final inspection process of the semiconductor wafer state in the manufacturing process of semiconductor-related elements, it is required to assume and measure the environmental temperature at which the semiconductor wafer will be used. One type of such a measuring device is a probe device that measures a wafer.

A support for measuring a wafer that is used in the above-mentioned probe device is described in Japanese Patent Application Laid-Open No. 58-220438. The above publication describes a structure in which the support on which the wafer is placed is electrically insulated from the probe device, and this support has a structure in which a fluid circulates inside to set the temperature to a predetermined temperature. It doesn't belong to.

Therefore, a probe device that assumes and measures the environmental temperature will be described.

The above-mentioned probe device is composed of a part that transports wafers housed in a carrier one by one, and a measurement part that measures the transported wafers.

The configuration of the measuring section will be explained with reference to FIG. 5.

The measurement section (■) consists of a probe card (■) fixed to a swing insert (2a) that is placed inside the head plate (■), and a support (2) that is movable horizontally below the probe card (■).
(also referred to as a mounting section, chuck, or stage) is placed on the This support part (A) has a built-in circulation system (C) in which a cooled fluid for cooling the support body (C) circulates.

This circulation system 0 is constructed so as to uniformly cool the support 1 made of a conductive material that supports the wafer 0.

That is, a heat exchanger jacket (made of metal, for example, copper material) is placed on the bottom surface of the metal support (2) that supported the wafer 0.
) is provided to allow heat conduction.

Inside the steel pipe of the heat exchanger jacket (■), a conductive refrigerant 0 is pumped into the container (
11) The container (11) is constructed so that the flow is sent from within the container (11), and the container (11) is provided with a ground potential. Therefore, measurements were made with the support surface (7a) supporting the wafer (0) set to the ground potential via the heat exchanger jacket (to) and the refrigerant (0).

That is, the wafer 0 to be measured and inspected is supported on the support surface (7a), and a measurement signal AC voltage is applied between each chip electrode pad from the wafer surface side via the probe needle (12) to measure the wafer chip. Generally, the minute current flowing between electrode pads is measured to determine whether a wafer chip is good or bad.

(Problem to be Solved by the Invention) However, regarding the support (1) insulated from the probe device having the above configuration, the wafer 0 is not connected to the wafer tester (15
) measurement signal AC voltage is passed through the probe needle (12),
A voltage is applied between the electrode pads (14a, 14b) of each chip. This application causes the electrode pads (14a,
14b) A part of the minute current generated between the metal support surfaces (7
From a), it was found that there was a loss due to leakage to ground potential through the heat exchanger jacket (8) and the refrigerant (9). Even if wafer 0 was measured and inspected in such a loss state, the accurate capacitance value of the wafer chip (13) could not be measured, and there was a problem that measurement and inspection were impossible.

SUMMARY OF THE INVENTION An object of the present invention has been made in view of the above-mentioned conventional problems, and it is an object of the present invention to provide a probe device having a structure that prevents the generation of leakage current.

[Structure of the invention]

(Means for Solving the Problems) The probe device of the present invention is a device for measuring electrical characteristics by placing a sample on a support in which a fluid for setting a predetermined temperature circulates. The method is characterized in that at least the support surface of the support body that the sample body contacts is made of an insulating member.

(Function and Effect) Since the sample body is insulated with an insulating member and is placed on an electrically insulated support in which a fluid is circulated to set the temperature to a predetermined temperature, the sample body supported on the support body is It is cut off from the fluid circulating inside the support and electrically isolated from the probe device. Therefore, even if a measurement signal current is applied to the sample electrode, the leakage current from the back surface of the sample can be improved very slightly. Therefore, it is possible to measure the electrical characteristics of the sample body within the allowable leakage current.

(Example) Hereinafter, an example in which the probe device of the present invention is applied to a measuring device in a semiconductor wafer manufacturing process will be described with reference to the drawings.

In the above description, parts that are the same as those in the prior art will be described using the same reference numerals.

The above measuring device measures wafer chips formed on a wafer in one
There is a device, such as a wafer prober, that measures electrical characteristics by sequentially advancing each chip.

This wafer prober measures electrical characteristics by bringing a probe needle of a probe card provided on a surface facing the wafer into contact with an electrode pad formed on each wafer chip.

First, the external structure of this wafer prober will be explained with reference to FIG.

The wafer prober (16) is roughly divided into a loader section (17).
), a measuring section (18), and a loader section (17).
) After positioning the wafer transported from ), the measuring section (18)
It is designed to be measured.

Note that a scope (19) is provided above the measurement section (18). This scope (19) is used to visually observe the alignment between the wafer and the probe needle.

The loader section (17) takes out the wafer (0) from the wafer cassette (6a) containing the wafer (2), and transfers it to the support surface (20a) of the support (20) on the measurement section (18) side. It will be done.

The measurement unit (18) temporarily fixes and adsorbs the wafer 0, which has been transported via the loader unit (17), to the support (20) under vacuum pressure.
The support body (
The wafer (0) is aligned by driving and controlling the wafer (20). After this alignment, the wafer (0) is aligned.
0 moves to the lower side of the probe card (21), and the probe needles (22) come into contact with electrode pads formed on the wafer chip. The probe needle (2
2) is connected to the wafer tester (24) via the signal line (23).
It is connected to the. This wafer tester (24) measures the current and voltage of the wafer chip and determines whether the wafer chip is good or not.
This is used to judge defects.

The support (20) is a support surface (20) for measuring performance at a predetermined wafer temperature state for environmental testing.
a) Allow to cool. This cooling mechanism is based on this mounting body (20
) The support (20) is cooled by circulating a refrigerant, such as ethylene glycol (commonly known as antifreeze), in a copper tube of a heat exchanger jacket provided inside. Here, the heat exchanger jacket is made of copper having excellent thermal conductivity as a support (2
0) so as to be in close contact with the opposite surface. In this way, the support with a cooling function is constructed.

The structure of the support body (20) will be specifically explained with reference to FIG. 2.

A wafer 0 is placed on the mounting surface (20a) of the support (20).
is placed and temporarily fixed by suction from a vacuum suction hole (not shown). A plurality of guide holes (20b) in which pins described later appear are provided perpendicularly to the mounting surface (20a).

On the support surface (20a) and the opposite surface (20c), a heat exchanger jacket surface 0 is provided to allow maximum cooling heat conduction. A heater plate (25) is provided in close contact with the bottom surface (8a) of the heat exchanger (c), and heats the copper member of the heat exchanger jacket (8) to raise the temperature of the support (20). Adjustments are being made.

The heater plate (25) is electrically connected to a heater circuit. A shield plate (26) is fixed to the bottom surface (25a) of the heater plate (25) to block noise emitted from the heater plate (25). Here, the shield plate (2
6) is connected to frame ground.

As described above, the support (20) has the heat exchanger jacket (8), the heater plate (25), and the shield plate (26) fixed to the support (20), and the shield member (27) is on the opposite surface (200). ). The mechanism incorporated in this way is called a support part (28).

A member called a chamber (29) is provided on the bottom surface of the support part (28) concentrically with the center of the support part (20).
0) is fixed by tightening it with a screw (31) or the like.

The chamber (29) is made of ceramic to insulate it from the probe device.

Here, the support part (28) and the chamber (29
) is provided with a member called a three-pin (32) for separating the wafer 0 from the support surface (20a). The sleet bin (32) is connected to the support (20)
By moving up and down, the pin (
32a) appears.

The support body (20) is moved up and down by a pole screw (not shown) and a drive motor that rotates the pole screw. Such a wafer prober (16)
In order to prevent leakage current from the wafer, the wafer 0 may be measured in a state where the support (20) on which the wafer 0 is placed is insulated from the heat exchanger jacket (2).

The characteristic structure of this embodiment is that, as shown in FIG. 1, the wafer 0 and the heat exchanger jacket are electrically insulated.

The mounting body (33) is made of a heat-resistant, cold-resistant, and insulating material, such as a ceramic material. This ceramic member, for example, has a diameter of 13511n and a thickness of 9fl! It is provided with a circular ceramic member. This member is made of a material that does not generate dust.

The support surface (33a) of the support body (33) is provided with the wafer 0 placed thereon, and the opposite surface (33c) is provided with a heat exchanger jacket (2) in close contact with the support surface (33a).

A heater plate (
25) is provided.

Furthermore, a shield plate (
26) are arranged in close contact with each other. This shield plate (2
A shield member (26) is attached to the bottom surface of the support body (33) so as to surround the heat exchanger jacket (8), the heater plate (25), and the shield plate (26).
33c) with screws (33d) or the like.

Therefore, the wafer (0) placed on the support surface (33a)
is the probe needle a (22a) of the probe card (21)
) and probe needle b (22b), AC power from the wafer tester (24) is applied. Through this application, it is determined whether the wafer chip is good or bad based on the minute current and minute voltage values of the wafer pattern.

Since the support surface (33a) is insulated, the configuration is such that measurements can be made with extremely little leakage current.

Next, the effect will be explained.

After taking out the wafers one by one from the wafer cassette (6a) of the loader section (17) and pre-aligning them, the measuring section (
18). In this measurement unit (18), the receiver temporarily fixes the passed wafer (1) to the support surface (33a) of the support (33), for example by vacuum suction, and aligns the wafer (2) by controlling the drive in the planar direction and circumferential direction. do. The aligned wafer 0 is placed under the probe card (21). Wafer 0 placed on the lower side has corresponding probe needles a (22a) and probe needles b (22b).
contact. The wafer ■ in contact with this probe needle (
22) and is electrically connected to the wafer tester (24). It is possible to measure in a region where leakage current is extremely small in this measurement circuit.

As mentioned above, depending on the type of wafer, the bottom surface of the wafer may be used as the common electrode terminal for measurement. In this case, the difference in surface roughness of the support surface (33a) of the ceramic is 3 μs to 8 μs.
Process into s. Electroless nickel plating is applied to this processed support surface. Gold plating is applied to the top surface of this electroless nickel plating. In this way, the supporting surface of the ceramic (3
The gold-plated surface of 3a) becomes a good conductor. At this time, the noise generated from the noise source in the wafer prober (16) is absorbed by the copper member of the heat exchanger jacket 0, so the noise is blocked by the heat exchanger jacket (8). Therefore, noise does not reach the gold-plated portion located above the heat exchanger jacket (c). Therefore, even if the back surface of the wafer is a common electrode terminal, measurement can be performed without being affected by noise.

In the above, a ceramic member was used as the support (33).

Similar effects can be obtained with quartz or glass members.

The support surface (33a) of the support body (33) may be provided with a groove for easy suction of wafers, etc., and a suction hole may be provided at the bottom of this groove so that the wafer can be suctioned. good. The grooves may be concentrically arranged in double or triple layers, and a cross groove may be provided so as to be continuous with the double or triple grooves.

Characteristic Effects of this Example The support surface (33a) on which the wafer 0 is placed is provided with a ceramic member, and after the wafer 0 is placed on this ceramic member surface, the wafer 0 is measured with a wafer tester (24). ing. This measurement shows that even if a signal current is applied between the electrode pads of the wafer chip, leakage current from the supporting surface is extremely small. Therefore, accurate measurement results can be obtained within an acceptable range.

Since the support (33) on which the wafer 0 is placed is provided with a support made of a ceramic member, this support (33)
The heat exchanger jacket (8) surface of the copper member is brought into close contact with the opposite surface (back surface) (33c) of 33).

And the temperature from the heat exchanger jacket (c) surface,
For example, the cooling temperature is transferred to ceramics, which are good at retaining heat but poor at transferring it. Utilizing this property, the cold and hot air from the heat exchanger jacket (c) is transferred to the ceramic support (c).
Since it is in close contact with the opposite surface (back surface) (33c) of 33), cold and hot temperatures can be diffused. Therefore, the supporting surface (
Even if there is no temperature conduction function in the area of the central part of 33a), it is slowly conducted to the support surface (33a) from the temperature conduction function side outside the area of the central part. Therefore, the supporting surface (
It is possible to cool the support surface (33a) with a substantially uniform cooling temperature distribution.

In the above embodiment, since a ceramic member is provided as the insulating member, the thermal expansion of the support surface (33a) during addition, removal, and heating is small, and the difference in thermal expansion from that of wafer 0 during addition, removal, and heating is small. Therefore, the amount of friction between the support surface (33a) and the wafer 0 due to thermal expansion is small, and the generation of dust is extremely small. Furthermore, measurement can be performed with extremely little displacement of the wafer.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the mounting structure for explaining an embodiment of the probe device of the present invention, FIG. 2 is an explanatory diagram for explaining the mounting section structure of FIG. 1, and FIG. FIG. 4 is an explanatory diagram for explaining an embodiment in which the probe device shown in the figure is used as a wafer prober, and FIG. 4 is an explanatory diagram for explaining a conventional probe device. 1.18...Measurement part, 2...Head plate, 3.21...Probe card, 6...Wafer, 7...Support body, 8...Heat exchanger jacket, 9...・Cooling liquid, 12.22... Probe needle, 17... Loader section, 18... Measurement section, 20
...Support body, 20a...Support surface. 20c...Opposite side. Patent applicant Tokyo Electron Ltd. Figure 1 Figure 2 Figure 3 Figure 4 Figure 1

Claims (1)

[Claims] In an apparatus for measuring electrical properties by placing a sample on an electrically insulated support in which a fluid for setting a predetermined temperature circulates inside, at least the sample on the support 1. A probe device characterized in that a supporting surface in contact with which is made of an insulating member.