KR20230131339A - Probe card and method for controlling temperature of the same - Google Patents

Abstract

A probe card for testing a semiconductor die by contacting pads formed on a plurality of semiconductor dies on a wafer, comprising: a probe substrate including a plurality of probe pins in contact with the wafer; a printed circuit board electrically connected to the probe board; It includes an interposer that electrically connects the probe board and the printed circuit board, and the probe board includes at least one heater layer for generating heat in the probe board.

Description

Probe card and temperature control method thereof {PROBE CARD AND METHOD FOR CONTROLLING TEMPERATURE OF THE SAME}

The present invention relates to a probe card for testing a plurality of semiconductor dies by contacting pads formed on a plurality of semiconductor dies on a wafer, and more specifically, to a probe card with a self-heating function and a method of controlling its temperature.

A probe card is a device that connects a semiconductor chip (subject to be inspected) and test equipment to inspect the operation of the semiconductor. The probe pin mounted on the probe card sends electricity as it touches the wafer, and defective semiconductor chips are selected according to the signal returned.

1 shows a probe card according to the prior art. Referring to FIG. 1, a conventional probe card 10 includes a probe board 11 with a plurality of probe pins 14 attached, an interposer 13 connecting the probe board 11 and the printed circuit board 12, and It consists of a reinforcement plate (15).

Generally, a semiconductor operation test using the probe card 10 is conducted with the semiconductor wafer 16 placed on the chuck 17 of the prober, which is a test equipment, heated to a high temperature in order to take into account the usage environment of the semiconductor. do.

At this time, as shown in FIG. 1, the entire area of the thin semiconductor wafer 16 is in contact with the chuck 17, which is a heat source, so the temperature of the wafer 16 is the same as the temperature of the chuck 17. , Except for the plurality of probe pins 14 in contact with the semiconductor wafer 16 in the probe card 10, the probe board 11, printed circuit board 12, and reinforcement plate 15 are connected to the semiconductor wafer 16. ) and the chuck 17, which is a heat source, so the time to reach the saturation temperature and the saturation temperature are different from those of the semiconductor wafer 16. Additionally, since the probe substrate 11 is made of a different material from the semiconductor wafer 16, the amount of expansion is also different.

Here, the saturation temperature is the temperature for matching the positions of the pad of the semiconductor wafer 16 and the probe pin 14, and the heating time required for the probe card 10 to reach the saturation temperature is called the absorption time. It is called (soak time). For example, the absorption time can be as short as 20 minutes or as long as 1 hour.

Then, after the test on one semiconductor wafer 16 is completed, the next semiconductor wafer 16 is loaded onto the chuck 17 and the time required to match the position of the semiconductor wafer 16 and the probe card 10 is idle. It is called idle time. In this process, as the probe card 10 moves away from the chuck 17, which is a heat source, and the temperature decreases, the probe card 10 shrinks relative to the semiconductor wafer 16, causing the semiconductor wafer 16 to shrink. The positions of the pad and the probe pin 14 of the probe card 10 do not match.

In the production of the semiconductor wafer 16, the above-described absorption time and idle time cause time loss, and there is also a risk that the alignment between the pad of the semiconductor wafer 16 and the probe pin 14 may be deteriorated during the above-described process. This causes quality loss.

Korean Patent Publication No. 1951254 (registered on February 18, 2019) Korean Patent Publication No. 1366670 (registered on February 18, 2014)

The present invention is intended to solve the problems of the prior art described above, and seeks to provide a probe card that can efficiently shorten the time required for matching a semiconductor wafer and a probe card, absorption time, and idle time.

However, the technical challenges that this embodiment aims to achieve are not limited to the technical challenges described above, and other technical challenges may exist.

As a means to achieve the above-described technical problem, an embodiment of the present invention provides a probe card for testing a semiconductor die by contacting pads formed on a plurality of semiconductor dies on a wafer, and the probe card is in contact with the wafer. A probe substrate including a plurality of probe pins; a printed circuit board electrically connected to the probe board; A probe card may be provided, comprising an interposer that electrically connects the probe board and the printed circuit board, and the probe board includes at least one heater layer for generating heat in the probe board. .

Another embodiment of the present invention is a method of controlling the temperature of a probe card according to an embodiment of the present invention, comprising: detecting the temperature of the probe substrate from the temperature sensor; Comparing the sensed temperature of the probe substrate with the preset temperature; and operating the heater layer of the probe substrate when the temperature of the probe substrate is lower than the preset temperature, and stopping operation of the heater layer when the temperature of the probe substrate is higher than the preset temperature. can be provided.

The above-described means for solving the problem are merely illustrative and should not be construed as limiting the present invention. In addition to the exemplary embodiments described above, there may be additional embodiments described in the drawings and detailed description of the invention.

According to any one of the above-described means for solving the problems of the present invention, the substrate of the probe card can generate self-heating. Therefore, the time required for matching the semiconductor wafer and the probe card, the temperature specified in the absorption time can be reached more quickly, and the probe card can prevent the shape of the probe card's substrate from being deteriorated due to heat loss during idle time. can be provided.

1 shows a probe card according to the prior art.
Figure 2 is a configuration diagram of a probe card according to an embodiment of the present invention.
Figure 3 is an exemplary diagram for explaining a probe substrate according to an embodiment of the present invention.
Figure 4 is an exemplary diagram for explaining a heater layer according to an embodiment of the present invention.
Figure 5 is a graph showing the temperature change of a probe card using a probe board according to the prior art.
Figure 6 is a graph showing the temperature change of a probe card to which a probe substrate according to an embodiment of the present invention is applied.
Figure 7 is a flowchart of a method for controlling the temperature of a probe card according to an embodiment of the present invention.

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

Throughout the specification, when a part is said to “include” a certain element, this means that it may further include other elements rather than excluding other elements, unless specifically stated to the contrary. In addition, when a part is said to be "connected" to another part throughout the specification, this means not only when it is directly connected, but also when it is connected through another member in the middle, or electrically between other elements in the middle. This also includes cases where they are connected. Furthermore, throughout the specification of the present application, when a member is said to be located “on” another member, this includes not only the case where a member is in contact with another member, but also the case where another member exists between the two members. Additionally, expressions such as “first,” “second,” and the like used in this specification may modify various components regardless of order and/or importance, and may be used to distinguish one component from another component. It is only used and does not limit the corresponding components, and does not necessarily mean other components. For example, 'first direction' and 'second direction' may mean the same direction or different directions.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings.

Figure 2 is a configuration diagram of a probe card according to an embodiment of the present invention. Referring to FIG. 2 , the probe card 100 may include a probe board 110, a printed circuit board 120, an interposer 130, a probe pin 140, and a reinforcement plate 150. The probe substrate 110 may include a heater layer 111. However, the probe card 100 shown in FIG. 2 is only one implementation example of the present invention, and various modifications are possible based on the components shown in FIG. 2.

Referring to FIG. 2, the probe card 100 is formed by combining a reinforcement plate 150 and a printed circuit board 120, and an interposer 130 is located between the printed circuit board 120 and the probe board 110. . The probe board 110 may be arranged to be spaced apart from the printed circuit board 120 . For example, one side of the probe board 110 may be connected to the interposer 130, and the probe pin 140 may be fixedly attached to the other side.

The probe substrate 110 may include a plurality of probe pins 140 in contact with the wafer 160 . For example, the plurality of probe pins 140 may be mounted on the probe substrate 110 and contact the wafer 160 to receive electrical signals. The probe pin 140 may transmit an electrical signal received from the wafer 160 to the probe card 100.

The printed circuit board 120 may be electrically connected to the probe board 110. For example, the printed circuit board 120 and the probe board 110 may be connected to each other through the interposer 130.

The interposer 130 may electrically connect the probe board 110 and the printed circuit board 120. For example, the interposer 130 may be disposed between the printed circuit board 120 and the probe board 110 to connect the printed circuit board 120 and the probe board 110 to each other. The interposer 130 may be elastically supported on the printed circuit board 120 and the probe board 110, respectively.

The probe substrate 110 may include a plurality of heater layers 111 . The heater layer 111 may generate heat in the probe substrate 110, and there may be at least one heater layer 111. For example, the heater layer 111 may be composed of a first heater layer 111a and a second heater layer 111b.

The probe substrate 110 including the heater layer 111 may self-heat at the same temperature as the chuck 170 supporting the wafer 160. Through this, the probe card 100 according to the present invention can reach the saturation temperature in a faster time than the time required to match the wafer 160 and the absorption time.

Additionally, it is possible to prevent deterioration of the shape of the probe board 110 due to heat loss during idle time when the probe card 100 and the chuck 170 move away from each other. For example, as the probe card 100 and the chuck 170, which is a heat source, move away from each other during idle time, the pad of the wafer 160 is damaged due to shrinkage of the probe substrate 110 due to heat loss of the probe substrate 110. The position between the and probe pins 140 may be misaligned. At this time, the preset temperature of the probe substrate 110 can be maintained through self-heating of the probe substrate 110 so that the position of the probe pin 140 does not shift during idle time.

Figure 3 is an exemplary diagram for explaining a probe substrate according to an embodiment of the present invention. As shown in FIG. 3 , the probe substrate 110 may be composed of a heater layer 111, a ceramic layer 112, a ground layer 113, and a signal layer 114.

The probe substrate 110 may include a plurality of heater layers 111, and the heater layer 111 may include a first heater layer 111a and a second heater layer 111b. For example, the first heater layer 111a and the second heater layer 111b may be arranged to be spaced apart from each other.

The probe substrate 110 may further include a ceramic layer 112 between the first heater layer 111a and the second heater layer 111b. For example, the ceramic layer 112 may be disposed between the first heater layer 111a and the second heater layer 111b that are spaced apart from each other.

Figure 4 is an exemplary diagram for explaining a heater layer according to an embodiment of the present invention. Figure 4 (a) is an example of the first heater layer 111a, and (b) is an example of the second heater layer 111b.

As shown in Figures 4 (a), (b), and (c), the first heater layer 111a and the second heater layer 111b can be designed with metal wiring for heat generation. For example, the resistance value can be adjusted by adjusting the width, thickness, and length of the metal wiring designed in the first heater layer 111a and the second heater layer 111b. By adjusting the resistance value, the time for the probe board 110 to reach the preset temperature can be shortened or delayed, so the design of the metal wiring can be changed depending on the situation.

Referring to (a) of FIG. 4 , the first heater layer 111a may have metal wires arranged in a first direction. For example, the first heater layer 111a may include a plurality of layers 111a_1 and 111a_2. The plurality of layers 111a_1 and 111a_2 included in the first heater layer 111a may all include metal wires arranged in the first direction. As an example, a ceramic layer may be further disposed between the plurality of layers 111a_1 and 111a_2.

Referring to (b) of FIG. 4, the second heater layer 111b may have metal wires arranged in a second direction crossing the first direction. For example, the second direction may be perpendicular to the first direction. That is, the second heater layer 111b may be formed of metal wires arranged to be perpendicular to the first heater layer 111a.

For example, the second heater layer 111b may include a plurality of layers 111b_1 and 111b_2. The plurality of layers 111b_1 and 111b_2 included in the second heater layer 111b may all include metal wires arranged in the second direction. That is, the plurality of layers 111b_1 and 111b_2 included in the second heater layer 111b may all include metal wires arranged to intersect the first direction.

Referring to (c) of FIG. 4, the heater layer 111 includes a first heater layer 111a and a second heater layer 111b, and can improve the density of metal wiring, which is a hot wire. For example, the heater layer 111 includes a first heater layer 111a with metal wires arranged in a first direction and a second heater layer 111b with metal wires arranged in a second direction crossing the first direction. It can be included. For example, the first direction may be a longitudinal direction, and the second direction may be a horizontal direction.

In this way, the heater layer 111 can improve the density of heat rays. Accordingly, heat distribution can be made even in all areas of the probe substrate 110, and the absorption time and idle time required during the test process can be more efficiently shortened.

Referring again to FIGS. 2 and 3 , the probe substrate 110 may further include a temperature sensor 115 and a control unit 116. The probe substrate 110 may operate the heater layer 111 based on the temperature detected through the temperature sensor 115.

The temperature sensor 115 may detect the temperature of the probe substrate 110. For example, the temperature sensor 115 may measure the temperature of the probe board 110 and transmit a signal to the control unit 116 provided on the printed circuit board 120 through the interposer 130.

For example, the temperature sensor 115 may continuously measure the temperature of the probe substrate 110. For another example, the temperature sensor 115 may repeatedly measure the temperature of the probe substrate 110 at preset regular intervals.

The control unit 116 may control the temperature detected by the temperature sensor 115. For example, the control unit 116 may be a field programmable gate array (FPGA).

The control unit 116 may operate the heater layer 111 when the temperature detected by the temperature sensor 115 is lower than the preset temperature. For example, the control unit 116 may operate a relay element when the detected temperature is lower than a preset temperature. When the relay element operates, the power of the power supply wiring of the heater layer 111 is applied to the wiring layer for heat generation of the probe board 110 to generate heat.

Here, the preset temperature may be a temperature at which the thermal strain of the probe substrate 110 matches the thermal strain of the wafer 160. As an example, the preset temperature may be set lower than the temperature of the chuck 170. The preset temperature may be an experimental value or a result value measured through simulation. As an example, the chuck temperature may be 120°C and the preset temperature may be 110°C.

On the other hand, the control unit 116 may stop the operation of the heater layer 111 when the temperature detected by the temperature sensor 115 is higher than the preset temperature.

For example, the control unit 116 may operate the heater layer 111 or stop the operation of the heater layer 111 based on the temperature of the probe substrate 110 measured through the temperature sensor 115. . Through this, the temperature of the probe substrate 110 can be set to be maintained at a preset temperature.

Figure 5 is a graph showing the temperature change of a probe card to which a probe board according to the prior art is applied, and Figure 6 is a graph showing the temperature change of a probe card to which a probe board according to an embodiment of the present invention is applied.

First, referring to FIG. 5, the conventional probe card not only takes an absorption time (a) to reach the saturation temperature state, but also is idle every time between testing one wafer 16 and testing the next wafer 16. It is taking time (b).

For example, the conventional probe board 11, which does not include a heater layer, is placed away from the chuck, which is a heat source, and time loss occurs due to absorption time (a) and idle time (b) during the test process.

On the other hand, referring to FIG. 6, the probe substrate 110 including the heater layer effectively reduces the absorption time (A) required for the probe card to reach the saturation temperature state through self-heating compared to the prior art (see FIG. 5). It can be shortened.

Additionally, since the temperature of the probe substrate 110 including the heater layer can be maintained at a preset constant temperature, the idle time (B) can also be omitted. For example, the idle time (B) required between testing one wafer 160 and testing the next wafer 160 can be effectively shortened compared to the prior art (see FIG. 5).

Through this, the probe card 100 according to the present invention effectively shortens the absorption time and idle time occurring during the test process, thereby reducing the wafer 160 test time, thereby reducing the time loss caused by the prior art. can be resolved.

Figure 7 is a flowchart of a method for controlling the temperature of a probe card according to an embodiment of the present invention. The temperature control method of the probe card shown in FIG. 7 includes steps processed in time series according to the embodiment shown in FIGS. 2 to 6. Therefore, even if the content is omitted below, it also applies to the method of controlling temperature in the probe card according to the embodiment shown in FIGS. 2 to 6.

In step S710, the temperature control method may detect the temperature of the probe substrate from a temperature sensor. For example, the temperature control method can continuously measure the temperature of the probe substrate through a temperature sensor. For another example, the temperature control method may repeatedly measure the temperature of the probe substrate at regular intervals using a temperature sensor.

In step S720, the temperature control method may compare the detected temperature of the probe substrate and a preset temperature. For example, the temperature control method may compare the measured temperature of the probe substrate with a preset temperature every time the temperature of the probe substrate is measured through a temperature sensor. Here, the preset temperature may be a temperature at which the thermal strain of the probe substrate matches the thermal strain of the wafer. As an example, the preset temperature may be set lower than the chuck temperature. As an example, the chuck temperature may be 120°C and the preset temperature may be 110°C.

In step S730, the temperature control method may operate the heater layer of the probe substrate when the temperature of the probe substrate is lower than the preset temperature, and may stop operation of the heater layer when the temperature is higher than the preset temperature.

For example, in the temperature control method, if the temperature of the probe substrate measured through the temperature sensor is lower than a preset temperature, the relay element can be operated to turn on the heater layer power. On the other hand, the temperature control method can stop the operation of the heater layer by turning off the power to the heater layer when the temperature of the probe substrate measured through the temperature sensor is higher than a preset temperature.

Through this, the temperature control method can maintain the temperature of the probe board at the set temperature during the test process. Therefore, the absorption time and idle time required during the test process can be effectively shortened.

In the above description, steps S710 to S730 may be further divided into additional steps or combined into fewer steps, depending on the implementation example of the present invention. Additionally, some steps may be omitted or the order between steps may be switched as needed.

The description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as unitary may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

100: Probe card
110: probe board
111: heater layer
120: printed circuit board
130: Interposer
140: probe
150: reinforcement plate
160: wafer
170: Chuck

Claims (7)

In the probe card for testing a plurality of semiconductor dies by contacting pads formed on a plurality of semiconductor dies on a wafer,
A probe substrate including a plurality of probe pins in contact with the wafer;
a printed circuit board electrically connected to the probe board;
It includes an interposer that electrically connects the probe board and the printed circuit board,
The probe substrate is,
A probe card comprising at least one heater layer for generating heat in the probe substrate.
According to claim 1,
The heater layer is,
a first heater layer with metal wires arranged in a first direction; and
A probe card comprising a second heater layer in which metal wires are arranged in a second direction crossing the first direction.
According to claim 2,
The probe substrate is,
A probe card further comprising a ceramic layer between the first heater layer and the second heater layer.
According to claim 1,
The probe substrate is,
A probe card further comprising a temperature sensor that detects the temperature of the probe substrate.
According to claim 4,
Further comprising a control unit for controlling the temperature detected by the temperature sensor,
The control unit,
A probe card characterized in that it operates the heater layer when the temperature detected by the temperature sensor is lower than a preset temperature, and stops operation of the heater layer when the temperature detected by the temperature sensor is higher than the preset temperature.
According to claim 5,
The preset temperature is,
A probe card, wherein the thermal strain of the probe substrate is at a temperature that matches the thermal strain of the wafer.
In the method for controlling the temperature of the probe card according to any one of claims 1 to 6,
detecting the temperature of the probe substrate from the temperature sensor;
Comparing the sensed temperature of the probe substrate with the preset temperature; and
A temperature control method of a probe card comprising operating the heater layer of the probe substrate when the temperature of the probe substrate is lower than the preset temperature, and stopping operation of the heater layer when the temperature is higher than the preset temperature.

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