JPH10116867A - Method for testing semiconductor wafer and temperature controller for testing equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temperature controller for high-temperature screening test equipment, capable of keeping wafers, which generate heat in conduction, at a desired temperature with accuracy. SOLUTION: The temperature controller comprises a large number of temperature controlling plates 2 that are installed opposite to a wafer energizing means, and have a smooth surface that is to be brought into tight contact with a wafer and supports the wafer and contains a heat medium flow path 4 therein; a thermostatic bath 11 that is connected with each of the temperature controlling plates through a first circulation path 15 of heat medium; a heat exchanger R that is connected with the thermostatic bath through a second circulation path 21 of heat medium; and a cooling water supply pipe 27 that is connected with the heat exchanger R and supplies the heat exchanger with cooling water. The temperature controller also contains a three-way valve 26 that adjusts the flow rate in the heat exchanger R installed in the second circulation path 21 according to signals from temperature detectors 9, 12 installed on the temperature adjusting plate 2 and the thermostatic bath 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for screening and testing semiconductor circuit elements and an apparatus used therefor.

[0002]

2. Description of the Related Art In the process of manufacturing an integrated circuit, a defective product due to crystal defects or impurities is detected by directly applying a probe to each chip formed in a wafer and conducting a characteristic test. After the check, the wafer is cut into chips, which are subjected to bonding, packaging steps, and the like to become IC components. These parts are subjected to a long-term energizing test while maintaining a high temperature of 120 to 150 ° C. in a burn-in device, and screening and removing what should be defective in the future due to potential defects. Sex tests have been performed.

As shown in FIG. 6, a burn-in device used for such a purpose is a horizontal partition plate having a box-shaped space surrounded by a heat insulating wall 100 provided with a slight gap from left and right wall surfaces. 101, an air flow path 102 is defined above the partition plate, a temperature test chamber 103 is defined below the partition plate 101, and the left and right ends of the partition plate 101 are directed toward the floor surface 104,
Air flow distribution plates 105 and 106 composed of a pair of perforated plates are vertically provided, and an air cooler 111 composed of a refrigerator and an air heater 11 composed of a heating wire heater are provided in the air passage 102.
2. A constant-temperature air supply device is configured by housing the blower fan 113, and supplies constant-temperature air of about 120 to 150 ° C. to the temperature test chamber 103 to form an appropriate ventilation space in the test chamber 103. The DUT 120, such as the IC components that were carried in and fixed, and the boards on which they were mounted, were connected to the current-carrying part formed on the wall on the rear side of the test chamber, and exposed to a high-temperature environment for several days under current-carrying, to perform screening. It is carried out.

In such a conventional test method, an energization test is performed on a large number of chips formed on a wafer to remove defective products, and then, after a mounting process, an IC component or a printed circuit board on which the IC component is assembled is mounted. In this state, screening is performed in a high-temperature environment. For parts that are removed by the screening test in a high-temperature environment, the test operations are duplicated, and the bonding, packaging, or assembly steps to the printed circuit board are all wasted. There was a disadvantage of becoming.

Further, since the DUT is configured to be maintained at a desired temperature by an air flow, it takes time for the DUT to reach a predetermined temperature, and the influence of heat generation due to energization of parts is reduced. The time lag was large to control, and the test accuracy was limited. In addition, since the DUT is packaged or already incorporated into the substrate, it occupies a large volume and requires space for airflow to flow between the DUTs on average. Therefore, the burn-in device, which is a test device, must be increased in size. However, since this size increase has a certain limit, the number of test pieces that can be processed is naturally limited.

[0006]

SUMMARY OF THE INVENTION It is a first object of the present invention to disclose a method of a high-temperature screening test with high accuracy, which eliminates waste in a test time and a manufacturing process.

A second object of the present invention is to disclose a high-temperature screening test apparatus which can quickly and accurately maintain a semiconductor wafer at a desired temperature.

[0008]

A first gist of the present invention is to predict a chip having a latent defect by energizing each of the integrated circuits while maintaining a wafer on which a large number of integrated circuits are formed at a predetermined high temperature. When performing a screening test for performing the above, the wafer is closely supported on a temperature control plate having a heat medium flow path therein, and the temperature control plate is held in a constant temperature bath through a first circulation flow path of the heat medium. And a heat medium is circulated between the thermostat and the temperature adjustment plate, and the thermostat is connected to a heat exchanger having a coolant flow path through a second circulation flow path of the heat medium. By circulating the heat medium between the heat exchanger and the thermostat, by adjusting the heat medium in the thermostat to a desired temperature by increasing or decreasing the flow rate of the heat medium flowing through the heat exchanger, Place the wafer on the temperature control plate In the method of testing a semiconductor wafer, comprising maintaining at a constant temperature of.

A first feature of the test method of the present invention is that a wafer on which hundreds to thousands or more of semiconductor elements or integrated circuits are formed is separated into chips without subjecting the wafer to high-temperature screening under a current. Is to do a test. For this purpose, it is necessary to accurately maintain the wafer to be tested at a predetermined temperature while being energized. As the energizing means, a probe type or a membrane type may be used, and one of these energizing means or a wafer provided on the other side so as to be able to approach and separate from each other may be used.

When a large number of elements and integrated circuits formed on the wafer are energized, the wafer made of semiconductor flakes becomes a kind of heating element.
In order to keep the temperature of the wafer constant at a predetermined accuracy (for example, ± 1 ° C. or less), the wafer must be constantly cooled.
(3-40000 Kcal / hr). In general, the heating means has a better response than the cooling means, so that the temperature control method by heating is relatively easy.However, the cooling means has a large response delay to the detection signal, and the temperature control method is accurate. Is difficult.

According to the test method of the present invention, a surface of a heat transfer block made of a heat conductive material is smoothened to a mirror finish or the like, and a heat medium flow path is formed inside the heat transfer block. Since the wafer is closely mounted on the plate and the wafer is directly cooled, the test object can be heated to the target temperature in a shorter time than conventional temperature control by airflow. In addition, the temperature control of the heat medium uses a heat exchanger provided in the thermostatic chamber via the second circulation flow path, and has a configuration in which the flow rate of the heat medium passing through the heat exchanger can be freely increased or decreased. The temperature of the heating medium in the thermostat can be reduced in a very short time by rapidly increasing the circulation amount of the heating medium in response to the detection signal of the sensor that detects the temperature change of the temperature control plate. And the result can be immediately reflected in the temperature of the temperature control plate.

As the cooling liquid to be passed through the heat exchanger, brine or the like cooled by a refrigerator may be passed, but cooling water supplied to other devices in the clean room may be used. In general, a wafer screening inspection apparatus is an apparatus having an extremely high-precision mechanism. Therefore, if a heat medium leaks from a temperature control plate or a pipe, serious damage may be caused. For this purpose, it is desirable that the heat medium flowing through the temperature control plate is a material that is not corrosive and has excellent electrical insulation. Examples of such a substance include Florinert (trade name, manufactured by Sumitomo 3M Limited), and Galden (trade name), which have a structural formula in which all hydrogen atoms in the chemical structural formula of silicone oil or polyether are replaced with fluorine atoms. , Italy, Montefuru
os company).

According to a second aspect of the present invention, in the test method defined by the first aspect, the heat exchanger overlaps a plurality of heat exchange plates in a gas- and liquid-tight manner, so that the heat exchange plates are disposed between the heat exchange plates. In a plate heat exchanger in which a heat medium flow path and a cooling fluid flow path to be heat-exchanged with each other are alternately provided adjacent to each other, the heat exchange plate has a heat transfer surface formed on a substantially circular flat plate. And a pair of passage openings for a heat medium and a pair of passage openings for a cooling fluid are formed with the heat transfer surface interposed therebetween, and each of the two pairs of passage openings is a flat plate. It is constituted by a plate-type heat exchanger that is configured so that a fluid flowing from the opening toward the flat plate peripheral portion is guided in a circumferential direction along the flat plate peripheral portion forming an arc by opening near the peripheral edge portion. Test method characterized by the fact that

[0014] In the test method defined in the first gist,
In order to increase the responsiveness of the control, a circulation flow rate adjusting means capable of increasing the circulation flow rate of the heat medium in the second circulation flow path by a necessary and sufficient amount is provided. A heat exchanger must be provided to ensure reliable cooling. The plate heat exchanger defined in the second aspect responds to such a demand.

In the plate heat exchanger according to the above,
The heat transfer surface may simply be a flat plate, or may be an uneven surface provided to increase the heat transfer area, for example, an uneven surface formed by herringbone projections, corrugated projections, or the like. Further, when the fluids to be heat-exchanged from each other flow out of the passage opening into the heat exchange flow path formed between the heat transfer surfaces, the side edges that collide with the flow in the outflow direction and kill the flow force are substantially formed. Flow out of one opening, even if the outflow direction is in the direction opposite to the other opening, is guided smoothly along the peripheral edge of the arc, Stagnation and low pressure loss, preventing the deposition of foreign matter on the heat transfer surface, which tended to occur in the vicinity of the passage opening, and combined with the vast heat transfer surface, excellent heat exchange Efficient.

According to a third aspect of the present invention, there is provided at least one temperature control plate having a smooth surface for closely supporting a wafer on which a large number of integrated circuits are formed and having a heat medium passage therein, A constant temperature bath connected to each of the adjusting plates via a first circulation flow path of the heat medium, a heat exchanger connected to the constant temperature bath via a second circulation flow path of the heat medium, and a connection to the heat exchanger A cooling liquid supply passage for supplying a cooling liquid to the heat exchanger, and a heat exchanger provided in the second circulation passage according to a signal from a temperature detector provided in the temperature control plate and the thermostatic bath. A temperature controller for a high-temperature screening test of a semiconductor wafer, comprising a controller for controlling a flow rate adjusting means.

This temperature controller is an example of a temperature controller used in an apparatus used in a high-temperature screening test method for chips formed on a semiconductor wafer, which is defined in the first aspect. The temperature control plate is provided facing the power supply means. Further, the plate may be provided with a fixing means for temporarily fixing the wafer on its smooth surface, and the heat medium may be evenly distributed to the plurality of temperature control plates. Means for flowing the volume may be provided.

According to a fourth aspect of the present invention, in the temperature controller defined in the third aspect, the heat exchanger overlaps a plurality of heat exchange plates in a gas- and liquid-tight manner, so that the heat exchange plates In a plate-type heat exchanger in which heat medium flow paths and coolant flow paths to be heat-exchanged with each other are provided alternately adjacent to each other, the heat exchange plate has a substantially circular flat heat transfer surface. And a pair of passage openings for a heat medium and a pair of passage openings for a coolant are formed with the heat transfer surface interposed therebetween, and each of the two pairs of passage openings is It is constituted by a plate-type heat exchanger that is configured to be opened in the vicinity of the flat plate peripheral portion, so that fluid flowing from the opening toward the flat plate peripheral portion is guided in the circumferential direction along the flat plate peripheral portion forming an arc. The temperature controller is characterized in that:

In the heat exchanger defined in the fourth aspect, the fluid passage opening has a substantially elliptical shape extending along the periphery of the arc-shaped flat plate, and the fluid contact opening of the heat exchange plates adjacent to each other is overlapped. The plate type heat exchanger having a configuration in which the parts are integrally joined by brazing is a gas-to-gas and liquid-tight overlap with each other. A gasket for liquid-tight isolation is not required, and the openings can be isolated from each other in a very small area.Therefore, there are few factors obstructing the flow force flowing along the arc-shaped peripheral edge, and a substantially elliptical shape is formed. The fluid passage opening also allows a sufficient distance between the opening and the arc-shaped peripheral portion while maintaining a sufficient opening area without changing the opening area, thereby promoting the fluid guiding effect of the flat plate peripheral portion. Has the effect of . Therefore, the heat exchanger has a high effect of preventing dirt from adhering to and clogging of the heat exchanger, and the integral connection of the heat exchange plate can significantly alleviate the disadvantage that the heat exchanger cannot be disassembled and cleaned, and can be applied to a high-purity liquid or high-pressure fluid. Applications can be expanded to applications.

According to a fifth aspect of the present invention, in the temperature controller defined by the third aspect or the fourth aspect, the second circulating flow path includes an outward pipe for passing the heat medium to the heat exchanger; A return pipe for the heat medium going to the thermostat via the heat exchanger;
And, with a circulation pump provided in the second circulation flow path,
The temperature controller is provided with a rotation speed control unit of the circulation pump as a heat exchanger flow control unit of the heat medium.

According to a sixth aspect of the present invention, in the temperature controller defined by the third aspect or the fourth aspect, the second circulating flow path includes a forward pipe for a heat medium to flow to the heat exchanger; A return pipe for the heat medium going to the thermostat via the heat exchanger;
A short-circuit pipe that directly connects the forward pipe and the return pipe; and a circulating pump interposed in the second circulating flow path. A temperature controller is provided with a flow control valve for increasing or decreasing the flow rate of at least one of a pipe and a return pipe.

[0022]

1 and 2 show an embodiment of a temperature controller incorporated in an apparatus for performing a test method according to the present invention. The temperature controller 1 includes, for example, 20 to 30 temperature control plates 2, 2,... According to the number of wafers to be tested at one time. As shown in FIG. 2, the temperature control plate 2 has a series of heat medium passages 4 arranged in a meandering manner in a heat transfer block 3 made of a plate-like aluminum that is a heat conductive material. The outlet is opened outside the heat transfer block 3. The heat medium flow path is formed by spirally shaping a copper pipe, casting it into an aluminum casting so as to wrap it, and opening an outlet and an inlet near the periphery of the plate 2 and near the center of the lower surface of the plate. Alternatively, a flat cylindrical space may be formed inside the heat transfer block 3 and a baffle plate may be provided in this space to form a meandering channel from the inlet to the outlet.

The upper surface of the plate 2 forms a mirror-finished smooth surface 5, and a peripheral edge 6 for wafer positioning is provided around the smooth surface. The heat transfer distance from the smooth surface to the heat medium flow path 4 is preferably long in order to eliminate the temperature unevenness depending on the place. However, as the distance becomes longer, the control response becomes worse. Determined by balance. Several openings 7 for vacuum pressure supply are opened in the smooth surface 5, and these small openings 7 connect all the small openings 7 in the heat transfer block 3 in series. The vacuum flow path 8 is connected to a vacuum source from the side of the heat transfer block via a pipe and a vacuum switching valve.

Reference numeral 9 denotes a temperature detector which is inserted into the heat transfer block from the side of the heat transfer block, detects a temperature near the center of the heat transfer block, and sends a detection signal to the temperature controller 10. The temperature control plate having such a configuration is provided on an appropriate moving means (not shown) so that the wafer placed on the smooth surface can be moved toward a means for supplying electricity to the wafer (not shown). Installed in As schematically shown in FIG. 1, a heating medium is provided between the thermostat 11 at the inlet 4a and the outlet 4b of each heating medium flow path 4, 4,. First circulation channel 15 for circulating and flowing
Are linked.

The first circulation channel 15 is provided with a heat medium supply pipe 16.
And a return pipe 17, a bypass pipe 18 for short-circuiting the return pipe and the supply pipe, and a circulating pump 19
However, the bypass pipes 18 are provided with bypass valves 20 for setting the flow rate of the bypass pipes, respectively.
The supply pipe 16 branches by the number of the temperature control plates 2 to form branch pipes 16 a,... Which are connected to the inlet 4 a of the plate 2, while the return pipe 17 is branched to the heat medium outlet 4 b of the plate 2. Are connected to each other, and each of the branch pipes 17a joins the return pipe on the upstream side of the connecting portion 18a between the bypass pipe 18 and the return pipe 17.

In each of the branch pipes 16a, the flow rate of the heat medium flowing through the heat medium flow path of the temperature control plate 2 per unit time is made uniform. Adjustment valves 16b,... Are interposed. Instead of the flow control valve 16b, a heat medium distribution chamber is provided at the branch of the branch pipe 16a, and a temperature control plate is provided at a position radially equidistant from the distribution chamber via a branch pipe of equal length. You may.

The constant temperature bath 11 is filled with silicone oil as a heat medium, and a temperature sensor 12 for detecting the temperature of the heat medium and a heater 13 comprising an electric heater are housed in the heat medium. ing. The heat medium has a low specific heat, a small change in viscosity (fluidity) with temperature, a boiling point higher than the operating temperature range and is chemically stable, and a non-corrosive and high electric insulation. Is required. In order to satisfy such a condition, ideally, the above-mentioned galden, florinate, etc. are used in addition to the silicone oil.

A second circulating flow path 21 for the heat medium is connected to the constant temperature bath 11, so that the heat medium circulates between the heat exchanger R and the heat exchanger R for cooling the heat medium. . The second circulation flow path 21 includes a forward pipe 22, a return pipe 23, a forward pipe 22, and a short-circuit pipe 24 that bypasses the return pipe 23.
, A circulation pump 25 is interposed, and a three-way valve 26 capable of electric flow control is interposed at a connection portion between the short-circuit pipe 24 and the return pipe 23. The temperature detector 9 inserted in the temperature control plate 2 is composed of a thermocouple, and its output signal is detected by a temperature controller 10 having a PID control circuit in an analog manner, and based on the detected signal, The three-way valve 26 is continuously controlled. In return pipe 2 instead of three-way valve 26
3. Each of the short-circuit tubes 24 may be provided with a flow control valve.

The three-way valve 26 reduces or increases the flow rate of the heat medium passing through the heat exchanger by increasing or decreasing the flow rate of the short-circuit pipe 24 and the return pipe 23 in accordance with a signal from the temperature controller 10. Is changed from 0 to the capacity limit of the circulation pump 25 to adjust the temperature of the heat medium in the thermostat 11. Therefore, instead of the short-circuit pipe 24 and the three-way valve for adjusting the flow rate thereof, the heat exchanger flow rate adjusting means uses the rotation speed of the circulation pump (the rotation speed of the pump drive motor) based on the detection signal of the temperature detector 9. The flow rate of the heat exchanger may be changed by controlling the temperature controller 10 to change the flow rate continuously. In a flow path on the other side adjacent to the heat medium flow path of the heat exchanger R, a cooling water supply pipe 27 and a cooling water return pipe 28 that are drawn in as cooling water as cooling water for equipment in a clean room are provided. Connected. The cooling water return pipe 28 detects the temperature of the cooling water and increases or decreases the flow rate in the pipe.
9 are interposed.

As the heat exchanger R, a plate heat exchanger R as shown in FIGS. 3 to 5 is used. Of course, a device having another configuration can be used, except for its performance. FIG. 3 is a partially omitted cross-sectional explanatory view as viewed from a cross-sectional direction along AA in FIG. 4. The plate heat exchanger R is configured by overlapping the heat exchange plates 40 as shown in FIG. 4 and integrally connecting the overlapping portions by brazing.
The brazing is appropriately performed according to the metal material of the heat exchange plate, such as a method in which the heat exchange plate 40 itself is formed of a brazing sheet and heated in a furnace, or a method in which the sheet-shaped brazing material is interposed and heated in a vacuum furnace. Applied.

The heat exchange plate 40 is formed of a substantially circular metal plate, and a rising edge 42 is formed on a peripheral edge portion 41 of the heat exchange plate 40 while slightly rising in diameter. The end edge of the rising edge 42 is bent in a diametrical direction (in a direction substantially perpendicular to the rising direction of the rising edge), and is deviated by a certain width from the substantially circumferential shape of the rising edge 42. And a flange portion 42a extending toward the front side. In FIG. 4, the heat transfer surface 4 is formed by press-forming a herringbone projection 43 that is bent in a mountain shape, leaving a slight flat portion above and below the round metal plate.
4.

With the heat transfer surface 44 interposed, the flat portion
A pair of passage openings 45a and 45b for the first fluid (heat medium) and a pair of passage openings 46a and 46b for the second fluid (cooling water) are formed at a slight distance from the peripheral portion 41. Have been. These passage openings 45a, b, 46a, b
Of the two virtual lines orthogonal to each other at the center of the heat exchange plate,
The openings 5a and 45b and the openings 46a and 46b are respectively line-symmetrical, and the openings 45a and 46a,
The openings 45b and 46b are respectively line-symmetrical,
positioned. Each opening has a substantially elliptical shape extending along the direction in which the arc formed by the rising edge 42 (or the peripheral edge portion 41) extends. Is kept.

The heat exchange plate 4 having such a configuration
0 is superimposed on the herringbone projection so that the bending directions of the herringbone projections are opposite to each other.
And the heat exchange flow path of the second fluid (cooling water),
Formed alternately. Opening edges 46c of openings 46a, b,
d is the front side of the peripheral edge of the opening in FIG.
Are integrally joined to the periphery of the opening of another heat exchange plate 40a (see FIG. 5) that overlaps the heat exchange plate 40 from above in FIG. Similarly, the periphery of the openings 45a and 45b is
It is integrally joined to the periphery of the opening of another heat exchange plate that comes into contact with the back side of the paper.

A front frame plate 52 is attached to the front side of the heat exchange plate thus integrated and integrated, and an end frame plate 53 is attached to the back side thereof.
By providing the inlet and outlet for the heat exchange fluid, the heat exchanger is completed. In FIG. 4, if the passage opening on the inlet side of the first fluid (heat medium) is 45a, the fluid entering from the first fluid inlet opening in the end frame plate 53 in FIG. A plurality of heat exchange flow paths, which flow between the heat transfer surfaces, merge at the outlet-side passage opening 15b, and communicate with the passage opening 45b. From one fluid outlet (not shown) it goes out of the heat exchanger.

First fluid (heat medium) and second fluid (cooling water)
Are flowing in a countercurrent state, the passage opening 46b serves as an inlet passage for the second fluid, and a second fluid inlet 56 is provided in the front frame plate so as to face the inlet passage, and the lower passage opening 46a Is the outlet channel. The first and second fluids to be heat-exchanged with each other flow adjacently via the heat transfer surface of the heat exchange plate and exchange heat. At this time, the fluid that has entered the heat exchanger R flows into the heat exchange channel from the branch channel formed by the passage opening 45a (or 46b). At this time, the flow from the passage opening 45a (or 46b) radially flows out of the opening radially and without interruption.

In particular, the flow in the direction opposite to the outlet opening (45b) is guided by the rising edge 42 provided on the circular arc-shaped peripheral portion 41, so that it does not stay. FIG.
, The left half of the heat transfer surface 44 is farther from the outlet opening than the right half, and thus is susceptible to pressure loss.
Since the passage area 48 for the first fluid extending in an arc shape is secured also between the first rising edge 42 and the rising edge 42 facing the opening, the flow in this direction is made easier to flow and stays there. There is no. Therefore, the heat exchange rate is improved, and the deposition and deposition of foreign substances can be prevented, and the heat transfer surface can be prevented from being stained or clogged. In the above description, the function and effect of the outlet opening are exclusively described. However, it is needless to say that the effect of the heat exchange plate having the arc-shaped peripheral portion is similarly exhibited in the inlet opening. That is, the fluid that has passed through the heat transfer surface is guided to the inlet opening by the arc-shaped peripheral edge portion, flows into the opening peripheral edge from all directions, and does not stay in the flowing direction.

[0037]

A method of performing a high-temperature screening test using the above apparatus will be described. When the temperature of the heat medium in the thermostat is equal to or lower than a set constant value at the time of rising of the temperature controller, the temperature sensor 12 detects the temperature, and the heater 13 is operated, so that the heat medium temperature is reduced to a predetermined value. Raise to temperature. At this time, the heat medium flow rate of the heat exchanger R is kept at the minimum. When the temperature control plate 2 reaches a predetermined temperature, the heater is stopped, and based on a signal from the temperature detector 9, the temperature controller 10 opens and closes the three-way valve 26 to maintain the temperature control plate at the predetermined temperature. I do. Bypass valve 20,
The adjustment of the flow control valve 16b is not necessary if it is set once according to the test temperature.

After the temperature control plate is brought into a steady state through these steps, when the wafer is supplied onto the temperature control plate, it is fixed on the smooth surface 5 by the vacuum suction force. Next, the plate 2 is moved and brought into contact with the energizing means to maintain the energized state for a required time. When the wafer generates heat by energization, the temperature of the plate 2 rises, and accordingly, the temperature of the heating medium in the thermostat 11 also starts to rise. Temperature detector 9
Immediately detects this and increases the flow rate through the heat exchanger R, whereby the temperature of the thermostat decreases and the temperature of the plate also decreases, so that the temperature regulating plate
A predetermined temperature will be maintained.

[0039]

The temperature controller according to the above embodiment can quickly cool the temperature of the heat medium with a highly efficient heat exchanger. The temperature control of the heat medium can be performed by increasing or decreasing the flow rate through the heat exchanger. The responsiveness is extremely high and the accuracy is extremely high because the cooled heat medium is mixed with the heat medium in a large volume thermostat to level the temperature and then supplied to the temperature control plate. The wafer temperature can be controlled at a high level, and the test accuracy can be significantly improved as compared with the conventional airflow test, the test time can be significantly reduced, and the waste of resources is reduced and the cost is reduced. it can.

[Brief description of the drawings]

FIG. 1 is a conceptual explanatory view showing an embodiment of the present temperature controller.

FIG. 2 is an explanatory sectional view showing details of a temperature control plate 2 of FIG. 1;

FIG. 3 is a diagram showing a heat exchanger R shown in FIG.
It is explanatory drawing shown in A section.

FIG. 4 is an explanatory view showing a heat exchange plate of the heat exchanger shown in FIG.

FIG. 5 is a sectional view taken along the line BB in FIG. 4;

FIG. 6 is an explanatory diagram showing an example of a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Temperature controller 2 Temperature control plate 3 Heat transfer block 4 Heat medium flow path 5 Smooth surface 7 Vacuum supply small hole 9 Temperature detector 10 Temperature controller 11 Constant temperature bath 12 Temperature sensor 13 Heater 15 First circulation flow path 16b Flow control valve 19, 25 Circulation pump 26 Three-way flow control valve 27 Cooling water supply pipe 28 Cooling water return pipe 29 Temperature type water control valve R Plate heat exchanger

Claims (6)

[Claims] When conducting a screening test for predicting a chip having a potential defect by energizing each of the integrated circuits while maintaining a wafer on which a large number of integrated circuits are formed at a predetermined high temperature, The wafer is closely supported on a temperature control plate having a heat medium flow path therein, and the temperature control plate is connected to a constant temperature bath via a first circulation flow path of the heat medium, thereby heating the heat medium to the constant temperature. Circulating between the tank and the temperature control plate, and further connecting the constant-temperature bath to a heat exchanger having a coolant flow path through a second circulation flow path of the heat medium to connect the heat medium to the heat exchanger. Circulating between the thermostat and the constant temperature bath, and adjusting the heat medium in the constant temperature bath to a desired temperature by increasing / decreasing the flow rate of the heat medium flowing through the heat exchanger, thereby setting the wafer on the temperature control plate to a predetermined temperature. To maintain a constant temperature of Method of testing a semiconductor wafer to be. 2. A heat exchanger comprising a plurality of heat exchange plates.
In a plate heat exchanger in which the heat medium passages and the cooling water passages that are liquid-tightly overlapped and exchange heat with each other between the heat exchange plates are provided alternately adjacent to each other, the heat exchange plate Has a heat transfer surface provided on a substantially circular flat plate, and a pair of passage openings for a heat medium and a pair of passage openings for cooling water are formed with the heat transfer surface interposed therebetween. Each of the two pairs of passage openings is opened near the peripheral edge of the flat plate so that the fluid flowing from the opening toward the peripheral edge of the flat plate is guided in the circumferential direction along the peripheral edge of the flat plate forming an arc. The test method according to claim 1, wherein the test method is configured by the configured plate heat exchanger. 3. One or more temperature control plates each having a smooth surface for closely supporting a wafer on which a large number of integrated circuits are formed and having a heat medium passage therein, and a heat medium for each of the temperature control plates. A constant temperature bath connected through a first circulation flow path of the heat exchanger, a heat exchanger connected to the constant temperature bath through a second circulation flow path of a heat medium, and connected to the heat exchanger and cooled to the heat exchanger. A cooling liquid supply channel for supplying a liquid, and a signal from a temperature detector provided in the temperature control plate and the constant temperature bath,
A temperature controller for a high-temperature screening test of a semiconductor wafer, comprising a controller for controlling a heat exchanger flow rate adjusting means provided in a second circulation channel. 4. A heat exchanger comprising a plurality of heat exchange plates.
In a plate heat exchanger in which the heat medium passages and the cooling liquid passages which are liquid-tightly overlapped and exchange heat with each other between the heat exchange plates are alternately provided adjacent to each other, The plate is formed by providing a heat transfer surface on a substantially circular flat plate, and forming a pair of passage openings for a heat medium and a pair of passage openings for a coolant with the heat transfer surface interposed therebetween. Each of the two pairs of passage openings is opened in the vicinity of the peripheral edge of the flat plate, so that the fluid flowing from the opening toward the peripheral edge of the flat plate is guided in the circumferential direction along the peripheral edge of the flat plate forming an arc. 4. The temperature controller according to claim 3, wherein said temperature controller comprises a plate heat exchanger. 5. A second circulation flow path is provided in the forward path for the heat medium to go to the heat exchanger, a return path to the constant temperature bath via the heat exchanger, and in the second circulation path. 5. A temperature controller according to claim 3, further comprising a circulation pump, and a rotation speed controller for the circulation pump as a heat exchanger flow rate controller for the heat medium. 6. A second circulation flow path comprising: a forward pipe in which a heat medium goes to a heat exchanger; a return pipe in which a heat medium passes through a heat exchanger to a thermostat;
A short-circuit pipe that directly connects the forward pipe and the return pipe; and a circulating pump interposed in the second circulating flow path. 5. The temperature controller according to claim 3, further comprising a flow control valve for increasing or decreasing the flow rate of at least one of the pipe and the return pipe.