Antenna device and temperature detection method

Abstract

The present invention provides an antenna device and a temperature detection method. The antenna device of the exemplary embodiment has a first metal layer, a first dielectric layer arranged on the first metal layer, a second metal layer arranged on the first dielectric layer, and a second dielectric layer arranged on the second metal layer, the antenna device has a first metal terminal and a second metal terminal arranged on the second dielectric layer, and a temperature detector arranged on the second dielectric layer, the first metal terminal and the second metal terminal are arranged separately from each other, each of a pair of input and output terminals of the temperature detector is electrically connected to each of the first metal terminal and the second metal terminal, the second metal layer has a first part and a second part arranged on the first dielectric layer, the first part and the second part are arranged separately from each other, the first metal terminal is arranged above the first part, and the second metal terminal is arranged above the second part, and the material of the first dielectric layer has a higher thermal conductivity and higher heat resistance than FR-4 resin.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure relate to an antenna device and a temperature detection method. Background Art

[0002] Various small-sized antennas (tag antennas) have been developed. The technology involved in such an antenna is disclosed in, for example, Patent Document 1 (Japanese Patent Publication No. 2016-146558). The antenna includes a dielectric, a metal layer, a radiation element layer, and a non-contact power supply element. The metal layer is disposed on one side of the dielectric layer. The radiation element layer is disposed on the other side of the dielectric layer. The radiation element layer has a slit portion. The slit portion is disposed in the central portion of the radiation element layer. The non-contact power supply element is disposed above the slit portion. Summary of the invention

[0003] When detecting the temperature of a wafer placed on an electrostatic chuck, the temperature is detected using a temperature detector disposed on the wafer, and sometimes the detection result may be wirelessly transmitted to an external receiving device via an antenna disposed on the wafer. The present disclosure provides a technology that can effectively transmit the detection result of the wafer temperature using an antenna disposed on the wafer.

[0004] In an exemplary embodiment, an antenna device is provided. The antenna device comprises a first metal layer, a first dielectric layer disposed on the first metal layer, a second metal layer disposed on the first dielectric layer, and a second dielectric layer disposed on the second metal layer. The antenna device also comprises a first metal terminal and a second metal terminal disposed on the second dielectric layer, and a temperature detector disposed on the second dielectric layer. The first metal terminal and the second metal terminal are disposed separately from each other. Each of a pair of input and output terminals of the temperature detector is electrically connected to each of the first metal terminal and the second metal terminal. The second metal layer comprises a first portion and a second portion disposed on the first dielectric layer. The first portion and the second portion are disposed separately from each other. The first metal terminal is disposed above the first portion. The second metal terminal is disposed above the second portion. The first dielectric layer has a higher thermal conductivity and a higher heat resistance than FR-4 resin.

[0005] According to the present disclosure, it is possible to provide a technology capable of satisfactorily transmitting the detection result of the temperature of a wafer using an antenna provided on the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 FIG. 1 is a diagram illustrating the appearance of an antenna device according to an exemplary embodiment.

[0007] Figure 2 It is an example Figure 1 A diagram showing a cross-sectional structure of an antenna device.

[0008] Figure 3 It is an example Figure 1 A diagram showing the structure on the surface of an antenna device.

[0009] Figure 4 It is an example Figure 1 A diagram showing another structure of a cross-section of an antenna device is shown.

[0010] Figure 5 is a flow chart showing a temperature detection method according to an exemplary embodiment.

[0011] Figure 6 It is an example Figure 1 The antenna device shown is a cross-sectional view of a state in which it is provided on a wafer.

[0012] Figure 7 It is used to illustrate Figure 1 A diagram showing the effect of the antenna arrangement. DETAILED DESCRIPTION

[0013] Various exemplary embodiments are described below. In an exemplary embodiment, an antenna device is provided. The antenna device includes a first metal layer, a first dielectric layer disposed on the first metal layer, a second metal layer disposed on the first dielectric layer, and a second dielectric layer disposed on the second metal layer. The antenna device also includes a first metal terminal and a second metal terminal disposed on the second dielectric layer, and a temperature detector disposed on the second dielectric layer. The first metal terminal and the second metal terminal are configured separately from each other. Each of a pair of input and output terminals of the temperature detector is electrically connected to each of the first metal terminal and the second metal terminal. The second metal layer includes a first portion and a second portion disposed on the first dielectric layer. The first portion and the second portion are configured separately from each other. The first metal terminal is disposed above the first portion. The second metal terminal is disposed above the second portion. The first dielectric layer has a higher thermal conductivity and higher heat resistance than FR-4 resin. Therefore, since the antenna device has relatively excellent thermal conductivity and heat resistance, the antenna device can work well even in a relatively high temperature environment. Moreover, even if the antenna device is placed on a metal component such as a metal plate, the antenna device can be arranged with the first metal layer facing the metal component, thereby reducing the influence of the metal component on the antenna device.

[0014] In an exemplary embodiment, the material of the first dielectric layer includes aluminum nitride. Thus, since the antenna device includes aluminum nitride having relatively excellent thermal conductivity and heat resistance, the antenna device can operate well even in a relatively high temperature environment. Furthermore, even if the antenna device is placed on a metal component such as a metal plate, the antenna device can be arranged with the first metal layer facing the metal component, thereby reducing the influence that the antenna device may receive from the metal component.

[0015] In an exemplary embodiment, the first dielectric layer has a first layer disposed on the first metal layer, a second layer disposed on the first layer, and a third layer disposed on the second layer. The second metal layer is disposed on the third layer. The materials of the first layer and the third layer are both glass containing SiO2. The material of the second layer is silicon. Thus, since the antenna device has a three-layer structure (glass containing SiO2 / silicon / glass containing SiO2) with relatively excellent thermal conductivity and heat resistance, it can work well even in a relatively high temperature environment. Moreover, even if the antenna device is used by being placed above a metal component such as a metal plate, the antenna device can be configured by arranging the first metal layer toward the metal component, thereby reducing the influence that the antenna device may receive from the metal component.

[0016] In an exemplary embodiment, the material of the first layer and the third layer is quartz. Thus, quartz can be used as the glass containing SiO2 which is the material of the first layer and the third layer.

[0017] In an antenna device according to an exemplary embodiment, the temperature detector may be a non-powered temperature sensor using surface acoustic waves. Thus, the temperature detector is a non-powered temperature sensor, so the antenna device can be used at any position in a confined space where power supply is difficult (for example, in a plasma processing device).

[0018] In the antenna device according to one exemplary embodiment, the first metal terminal and the second metal terminal can be arranged at the center or edge of the surface of the second dielectric layer.

[0019] In an exemplary embodiment, a temperature detection method is provided. The temperature detection method is a method for detecting the temperature of a wafer on an electrostatic chuck. In the temperature detection method, a wafer provided with an antenna device having a temperature detector is placed on the electrostatic chuck. In the temperature detection method, the temperature detector then receives a first signal sent from an external antenna to the antenna device, the temperature detector outputs a second signal based on the first signal, and the antenna device sends the second signal to the external antenna. The first signal is a signal for exciting the temperature detector in order to detect the temperature. The second signal is a signal indicating the temperature detected by the temperature detector. The antenna device comprises a first metal layer, a first dielectric layer provided on the first metal layer, a second metal layer provided on the first dielectric layer, and a second dielectric layer provided on the second metal layer. The antenna device also comprises a first metal terminal and a second metal terminal provided on the second dielectric layer, and a temperature detector provided on the second dielectric layer. The first metal terminal and the second metal terminal are configured to be separated from each other. Each of a pair of input and output terminals of the temperature detector is electrically connected to each of the first metal terminal and the second metal terminal. The second metal layer has a first part and a second part which are arranged on the first dielectric layer. The first part and the second part are arranged separately from each other. The first metal terminal is arranged above the first part. The second metal terminal is arranged above the second part. The first dielectric layer has a higher thermal conductivity and a higher heat resistance than FR-4 resin. Therefore, since the antenna device has relatively excellent thermal conductivity and heat resistance, the antenna device can work well even in a relatively high temperature environment such as during plasma processing. Moreover, even if the antenna device is placed on a metal component such as a metal plate (electrostatic chuck, etc.) for use, the antenna device can be arranged by facing the first metal layer toward the metal component, thereby reducing the influence that the antenna device can receive from the metal component. Therefore, by placing the antenna device on a wafer that is placed on an electrostatic chuck in a plasma processing device and subjected to plasma processing, the antenna device can be well used even in temperature detection of a wafer being processed in a relatively high temperature environment.

[0020] In the temperature detection method according to an exemplary embodiment, the temperature detector 6 may be a non-powered temperature sensor using surface acoustic waves. As such, the temperature detector is a non-powered temperature sensor, and thus the antenna device can be used at any position in a confined space (e.g., a plasma processing device) where power supply is difficult.

[0021] Hereinafter, various exemplary embodiments will be described in detail with reference to the accompanying drawings. In addition, the same reference numerals are given to the same or corresponding parts in each of the drawings.

[0022] refer to Figure 1 , Figure 2 and Figure 3, a structure of an antenna device 10 according to an exemplary embodiment is described. Figure 2 In the figure, it is shown that Figure 1 1 is a cross section of the antenna device 10 taken along line AA shown in FIG. The antenna device 10 includes a first metal layer 1, a first dielectric layer 2, a second metal layer 3, a second dielectric layer 4, a pair of metal terminals (a first metal terminal 5a, a second metal terminal 5b), and a temperature detector 6. The first metal layer 1, the first dielectric layer 2, the second metal layer 3, and the second dielectric layer 4 are stacked in this order.

[0023] The first metal layer 1 has a back surface RS1 of the antenna device 10. The first dielectric layer 2 is provided on the first metal layer 1 and in contact with the first metal layer 1. The second metal layer 3 is provided on the first dielectric layer 2 and in contact with the first dielectric layer 2. The second dielectric layer 4 is provided on the second metal layer 3 and in contact with the second metal layer 3. The second dielectric layer 4 has a main surface PS1 of the antenna device 10.

[0024] The first dielectric layer 2 may have a higher thermal conductivity and higher heat resistance than FR-4 (Flame Retardant Type 4) resin. The first dielectric layer 2 may have a thermal conductivity comparable to that of silicon (Si). For example, the material of the first dielectric layer 2 may be aluminum nitride (AlN).

[0025] Furthermore, the first dielectric layer 2 may include a Figure 4 The three-layer structure shown. Figure 4 The first dielectric layer 2 shown includes a first layer 2a, a second layer 2b, and a third layer 2c. The third layer 2c is provided between the first layer 2a and the second layer 2b. The first layer 2a, the second layer 2b, and the third layer 2c are stacked in this order.

[0026] The first layer 2a is provided on the first metal layer 1 and in contact with the first metal layer 1. The second layer 2b is provided on the first layer 2a and in contact with the first layer 2a. The third layer 2c is provided on the second layer 2b and in contact with the second layer 2b. The second metal layer 3 is provided on the third layer 2c and in contact with the third layer 2c.

[0027] The materials of the first layer 2a and the third layer 2c are both glass containing SiO2, preferably quartz. The material of the second layer 2b can be silicon (Si).

[0028] Regarding the size of the antenna device 10, the main surface PS1 may be, for example, a rectangular shape of about 10 to 30 mm x 30 to 60 mm. When the material of the first dielectric layer 2 is aluminum nitride, the thickness of the first dielectric layer 2 may be, for example, about 0.60 to 0.80 mm. Figure 4In the three-layer structure shown, the thickness of each of the first layer 2a and the third layer 2c can be, for example, about 0.10 to 0.25 mm, the thickness of the second layer 2b can be, for example, about 0.20 to 0.60 mm, and the thickness of the second dielectric layer 4 can be, for example, about 0.5 to 0.7 mm.

[0029] Back to Figure 1 to Figure 3 The second metal layer 3 includes a first portion 3a and a second portion 3b disposed on the first dielectric layer 2. The first portion 3a and the second portion 3b are disposed between the first dielectric layer 2 and the second dielectric layer 4. The first portion 3a and the second portion 3b are disposed apart from each other. The gap between the first portion 3a and the second portion 3b defines a slit SL.

[0030] The first metal terminal 5a and the second metal terminal 5b are disposed on the second dielectric layer 4 (disposed on the main surface PS1 of the second dielectric layer 4) and are in contact with the second dielectric layer 4. The first metal terminal 5a and the second metal terminal 5b are disposed separately from each other. The gap between the first metal terminal 5a and the second metal terminal 5b is defined above the slit SL. The first metal terminal 5a is disposed above the first portion 3a. The second metal terminal 5b is disposed above the second portion 3b.

[0031] like Figure 3 As shown, the first metal terminal 5 a and the second metal terminal 5 b may be arranged at the center CA or the edge EA of the main surface PS1 of the second dielectric layer 4 .

[0032] The temperature detector 6 is provided on the second dielectric layer 4 (provided on the main surface PS1 of the second dielectric layer 4) and is in contact with the second dielectric layer 4. Each of a pair of input / output terminals (input / output terminal 6a, input / output terminal 6b) of the temperature detector 6 is electrically connected to each of the first metal terminal 5a and the second metal terminal 5b. The input / output terminal 6a and the first metal terminal 5a, and the input / output terminal 6b and the second metal terminal 5b can be electrically connected by, for example, wire bonding.

[0033] The temperature detector 6 is a non-powered temperature sensor using surface acoustic waves and does not include a signal processing circuit.

[0034] More specifically, the temperature detector 6 can be a SAW (Surface Acoustic Wave) sensor. The temperature detector 6 of the SAW sensor has a piezoelectric substrate, a comb-tooth electrode (Interdigital Transducer: IDT) and a reflector (not shown) arranged on the piezoelectric substrate. The comb-tooth electrode is electrically connected to the input-output terminal 6a and the input-output terminal 6b, and is configured separately from the reflection circuit. The comb-tooth electrode and the reflector are configured so that the SAW propagates on the surface of the piezoelectric substrate between the comb-tooth electrode and the reflection circuit. The temperature detector 6 of the SAW sensor does not require a battery, so it is not limited to the operating temperature range of the battery, and the operating temperature range is relatively wide, for example, it can be about -100 to 250°C.

[0035] refer to Figure 5 , a temperature detection method based on the antenna device 10 having the temperature detector 6 is described. Figure 5 The flowchart shown in the figure shows a method MT according to an exemplary embodiment of a temperature detection method. The method MT may be, for example, a method for detecting the temperature of a wafer W disposed in a processing space such as a plasma processing apparatus.

[0036] First, in Figure 5 In the method MT shown, the wafer W( Figure 6 ) is placed on an electrostatic chuck (ESC) in a processing space (process ST1). At this time, an antenna device 10 having a temperature detector 6 is provided on the wafer W. The back surface RS2 of the wafer W is in contact with the electrostatic chuck. The antenna device 10 having the temperature detector 6 is arranged in a recess GL provided on the main surface PS2 of the wafer W. The back surface RS1 of the antenna device 10 is in contact with the bottom surface of the recess GL. The temperature detector 6 transmits and receives signals between an external antenna OA connected to an external analysis device (computer) and pre-arranged around the electrostatic chuck.

[0037] In step ST2 following step ST1, temperature detector 6 receives first signal SG1 transmitted from external antenna OA to antenna device 10 via second metal layer 3 and first and second metal terminals 5a and 5b (step ST2). First signal SG1 is a signal for activating temperature detector 6 to detect temperature.

[0038] In step ST3 following step ST2, the temperature detector 6 outputs the second signal SG2 based on the first signal SG1. The second signal SG2 is a signal indicating the temperature detected by the temperature detector 6. When the temperature detector 6 is a SAW sensor, the second signal SG2 can be generated by SAW generated on the piezoelectric substrate of the temperature detector 6 based on the first signal SG1.

[0039] In step ST4 following step ST3 , the antenna device 10 transmits the second signal SG2 to the external antenna OA.

[0040] The antenna device 10 of the structure described above is equipped with a temperature detector 6. The material of the first dielectric layer 2 of the antenna device 10 can be aluminum nitride. Alternatively, the first dielectric layer 2 can have a three-layer structure in which a first layer 2a as glass containing SiO2, a second layer 2b as silicon, and a third layer 2c as glass containing SiO2 are sequentially stacked on the first metal layer 1 instead of aluminum nitride. In this way, the first dielectric layer 2 has a higher thermal conductivity and higher heat resistance than FR-4 resin, and can especially have a thermal conductivity of the same degree as silicon. As a result, the antenna device 10 has aluminum nitride or a three-layer structure (glass containing SiO2 / silicon / glass containing SiO2) with better thermal conductivity and heat resistance than a tag antenna using FR-4 resin. Therefore, the antenna device 10 can work well even in a relatively high temperature environment (such as during plasma processing). In addition, the temperature detector 6 is a non-powered temperature sensor, so the antenna device 10 can be used at any position in a closed space where power supply is difficult (for example, in a plasma processing device).

[0041] Furthermore, even when the antenna device 10 is placed on a metal component such as a metal plate (electrostatic chuck, etc.), the antenna device 10 can be arranged with the first metal layer 1 facing the metal component, thereby reducing the influence of the metal component on the antenna device 10. Figure 7 .exist Figure 7 In the figure, the horizontal axis represents frequency, and the vertical axis represents VSWR (Voltage Standing Wave Ratio). Line GA1 represents the actual measurement result of the VSWR of the antenna device 10 obtained in a method where no metal component is provided. Line GB1 represents the actual measurement result of the VSWR of the antenna device 10 obtained in a method where no metal component is provided. Line GA2 represents the simulation result of the VSWR of the antenna device 10 obtained in a method where no metal component is provided. Line GB2 represents the simulation result of the VSWR of the antenna device 10 obtained in a method where a metal component is provided. According to Figure 7 It can be seen that the influence of the metal components on the VSWR of the antenna device 10 is relatively low in both actual measurements and simulation experiments.

[0042] The antenna device 10 can achieve at least the above-mentioned effects. Thus, for example, by placing the antenna device 10 on a wafer placed on an electrostatic chuck and subjected to plasma processing in a plasma processing apparatus, the antenna device 10 can be well used for temperature detection of a wafer being processed even in a relatively high temperature environment.

[0043] Various exemplary embodiments have been described above, but the present invention is not limited to the exemplary embodiments described above, and various omissions, substitutions, and changes may be made. Furthermore, elements in different exemplary embodiments may be combined to form other exemplary embodiments.

[0044] It should be understood from the above description that the various exemplary embodiments of the present disclosure are described in this specification for the purpose of illustration, and various changes can be made without departing from the scope and spirit of the present disclosure. Therefore, the various exemplary embodiments disclosed in this specification are not intended to be limiting, and their true scope and spirit are shown by the attached claims.

Claims

1. An antenna device comprising: 1st metal layer; a first dielectric layer disposed on the first metal layer; a second metal layer disposed on the first dielectric layer; a second dielectric layer disposed on the second metal layer; A first metal terminal and a second metal terminal provided on the second dielectric layer; as well as a temperature detector provided on the second dielectric layer, The first metal terminal and the second metal terminal are arranged separately from each other. Each of the pair of input / output terminals of the temperature detector is electrically connected to each of the first metal terminal and the second metal terminal. The second metal layer has a first portion and a second portion disposed on the first dielectric layer, The first part and the second part are configured separately from each other, The first metal terminal is arranged above the first portion, The second metal terminal is arranged above the second portion. The first dielectric layer has higher thermal conductivity and higher heat resistance than FR-4 resin.

2. The antenna device according to claim 1, wherein: The material of the first dielectric layer includes aluminum nitride.

3. The antenna device according to claim 1, wherein: The first dielectric layer has: a first layer disposed on the first metal layer; a second layer disposed on the first layer; and a third layer provided on the second layer, The second metal layer is disposed on the third layer, The materials of the first layer and the third layer are both glass containing SiO2. The material of the second layer is silicon.

4. The antenna device according to claim 3, wherein: The material of the first layer and the third layer is quartz.

5. The antenna device according to any one of claims 1 to 4, wherein: The temperature detector is a non-powered temperature sensor using surface acoustic waves.

6. The antenna device according to any one of claims 1 to 4, wherein: The first metal terminal and the second metal terminal are arranged at the center or edge of the surface of the second dielectric layer.

7. A temperature detection method, which detects the temperature of a wafer on an electrostatic chuck, In this temperature detection method, placing a wafer provided with an antenna device having a temperature detector on the electrostatic chuck, The temperature detector receives a first signal transmitted from an external antenna to the antenna device, The temperature detector outputs a second signal according to the first signal, The antenna device transmits the second signal to the external antenna, The first signal is a signal for activating the temperature detector in order to detect the temperature. The second signal is a signal indicating the temperature detected by the temperature detector. The antenna device comprises: 1st metal layer; a first dielectric layer disposed on the first metal layer; a second metal layer disposed on the first dielectric layer; a second dielectric layer disposed on the second metal layer; A first metal terminal and a second metal terminal provided on the second dielectric layer; as well as the temperature detector provided on the second dielectric layer, The first metal terminal and the second metal terminal are arranged separately from each other. Each of the pair of input / output terminals of the temperature detector is electrically connected to each of the first metal terminal and the second metal terminal. The second metal layer has a first portion and a second portion disposed on the first dielectric layer, The first part and the second part are configured separately from each other, The first metal terminal is arranged above the first portion, The second metal terminal is arranged above the second portion. The first dielectric layer has higher thermal conductivity and higher heat resistance than FR-4 resin.

8. The temperature detection method according to claim 7, wherein: The temperature detector is a non-powered temperature sensor using surface acoustic waves.

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