Detection device, detection method and semiconductor process chamber

Abstract

The invention relates to the field of plasmas, and discloses a detection device, a detection method and a semiconductor process chamber. The detection device comprises a conducting current detection unit which is in contact with a focusing ring of the semiconductor process chamber and is used for detecting whether conducting current exists in the focusing ring or not; and the starting state determination unit is used for determining whether the semiconductor process chamber is in a starting state or not according to the detection result of the conduction current detection unit. Therefore, the detection of the starting state in the semiconductor process chamber is realized, the cost is reduced, and the condition of misjudgment is avoided.

Description

Technical Field

[0001] The present invention relates to the field of plasma, and in particular to a detection device and a detection method, and a semiconductor process chamber. Background Art

[0002] With the rapid development of the integrated circuit manufacturing industry, capacitively coupled plasma (CCP) equipment has developed into one of the most widely used plasma generating devices. A typical capacitively coupled plasma device consists of two parallel plate electrodes. One of the electrodes is connected to a radio frequency source to excite and generate plasma; the other electrode is a ground electrode, and the two form a parallel plate capacitor. Among them, reactive ion etching (RIE) is the most representative capacitively coupled plasma equipment. During the normal process, the wafer will be transferred to the electrical static chuck (ESC) by a robot and fixed to the top of the chuck by electrostatic adsorption to ensure that the position of the wafer will not deviate during the ventilation and exhaust process. The process gas enters the chamber evenly through the air intake uniform flow plate (Shower Head, SHD), and the radio frequency power is fed to the ESC through the matcher to excite and generate plasma.

[0003] In order to determine whether the chamber is in a normal process state, that is, to determine whether plasma is generated, the prior art mainly detects the plasma spectrum intensity and compares the detected plasma spectrum intensity with a preset reference threshold. The detection scheme in the prior art is costly and depends on the preset reference threshold, which is prone to misjudgment. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a detection device and a detection method, and a semiconductor process chamber.

[0005] In a first aspect, an embodiment of the present invention provides a detection device, which is applied to a semiconductor process chamber, wherein the semiconductor process chamber includes a focusing ring, and the detection device includes: a conduction current detection unit, which is in contact with the focusing ring of the semiconductor process chamber and is used to detect whether there is a conduction current in the focusing ring; and a ignition state determination unit, which is used to determine whether the semiconductor process chamber is in a ignition state based on the detection result of the conduction current detection unit.

[0006] Optionally, the conduction current detection unit includes: a wire; a wire fixing unit connected to the wire and in contact with the focusing ring, used to fix the wire to the focusing ring and transmit the conduction current to the wire when the conduction current exists in the focusing ring; and an electrical signal detection unit connected to the wire, used to detect the electrical signal to determine whether the conduction current exists in the focusing ring, wherein the electrical signal includes a current signal and / or a voltage signal.

[0007] Optionally, the electrical signal includes a voltage signal, and the electrical signal detection unit includes: a voltage-dividing resistor connected to the wire; and a voltage signal detection unit for detecting a voltage signal related to the voltage-dividing resistor.

[0008] Optionally, the voltage-dividing resistor includes a first resistor and a second resistor, the resistance of the first resistor is greater than the resistance of the second resistor, and the voltage signal detection unit is configured to detect a voltage signal across the second resistor.

[0009] Optionally, the conduction current detection unit further includes: an isolation unit, used to isolate the voltage-dividing resistor from the external environment so that the voltage signal detected by the voltage signal detection unit is only generated due to the conduction current in the focusing ring.

[0010] Optionally, the isolation unit includes: an insulating isolation kit, through which a wire passes to connect with a voltage divider resistor and a voltage signal detection unit; and a metal grounding shell surrounding the voltage divider resistor, the insulating isolation kit isolating the wire and the metal grounding shell.

[0011] Optionally, the metal grounding shell is provided with a first through hole, the insulating isolation kit is installed in the first through hole, and the voltage divider resistor is located in a space formed by the insulating isolation kit and the metal grounding shell.

[0012] In a second aspect, an embodiment of the present invention provides a semiconductor process chamber, comprising: a focusing ring; and the above-mentioned detection device, wherein a conduction current detection unit in the detection device is electrically connected to the focusing ring.

[0013] Optionally, the conduction current detection unit includes a wire, a wire fixing unit and an electrical signal detection unit, and the semiconductor process chamber also includes: a carrying plate, located in the cavity, having a carrying surface, the carrying surface is used to carry the wafer, and the focusing ring surrounds the outside of the carrying surface; a grounding ring, located in the cavity and in contact with the focusing ring, the wire passes through the second through hole inside the grounding ring and is connected to the wire fixing unit, and the wire fixing unit is in contact with the focusing ring.

[0014] Optionally, the conduction current detection unit further includes an isolation unit, the isolation unit includes an insulating isolation kit and a metal grounding shell, the side wall of the cavity is provided with a third through hole, and the metal grounding shell is arranged in the third through hole.

[0015] In a third aspect, an embodiment of the present invention provides a detection method applied to a semiconductor process chamber, wherein the semiconductor process chamber includes a focusing ring, and the detection method includes: detecting whether there is a conduction current in the focusing ring of the semiconductor process chamber; and determining whether the semiconductor process chamber is in a ignition state based on the detection result.

[0016] Through the above technical scheme, it is detected whether there is a conduction current in the focusing ring, and whether the semiconductor process chamber is in a ignition state is determined based on the detection result, thereby realizing the detection of the ignition state in the semiconductor process chamber; in the detection, there is no need to set a reference threshold, and whether the semiconductor process chamber is in a ignition state is directly determined based on the detection result, thereby avoiding dependence on the reference threshold and misjudgment due to inappropriate reference threshold setting; in the detection, there is no need to rely on expensive spectrometer equipment to detect spectral intensity, thereby reducing costs.

[0017] Other features and advantages of the present invention will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this specification. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0019] Figure 1 It is a schematic diagram of the structure of a detection device provided in one embodiment of the present invention.

[0020] Figure 2 It is a schematic diagram of a semiconductor process chamber structure with a detection device provided by another embodiment of the present invention.

[0021] Figure 3 It is a schematic diagram of the composition of a detection device provided in another embodiment of the present invention.

[0022] Figure 4 It is a side view of a partial structure of a detection device provided in another embodiment of the present invention.

[0023] Figure 5a 1 is a bottom view of a focus ring provided in another embodiment of the present invention.

[0024] Figure 5b is a cross-sectional view of a focusing ring provided in another embodiment of the present invention.

[0025] Figure 6 It is a partial enlarged view of a detection device provided by another embodiment of the present invention installed in a semiconductor process chamber.

[0026] Figure 7 It is a schematic diagram of the change curves of RF power, DC bias, and Ar707 characteristic spectrum lines before and after ignition provided by another embodiment of the present invention.

[0027] Figure 8 It is a logical schematic diagram of a detection device provided in another embodiment of the present invention.

[0028] Fig. 9 It is a flow chart of a detection method provided by another embodiment of the present invention. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] During the normal process, after plasma is generated in the chamber, the free radicals, electrons, and ions in the plasma will bombard the wafer surface under the action of the electric field and flow field and cause chemical or physical reactions.

[0031] In order to achieve the purpose of fast matching, more and more etchers now choose to use swept frequency matching to achieve the matching state, that is, swept frequency power supply plus semi-fixed matcher or fixed matcher plus plasma etcher. Under this structure, the static impedance of the back-end impedance of the power supply is generally designed to be closer to the 50 ohm load, so that during the process, the power supply only needs to be slightly adjusted by sweeping the frequency to achieve the matching state. However, when the load is close to 50 ohms, it is easy to achieve a static matching state in the low-pressure process - that is, the RF power is completely absorbed by the back-end devices, the power supply output power is normal, there is no reflected power, but the chamber is not excited to form plasma. When in a static matching state, it is difficult to judge whether the inside of the chamber is in a normal process state only from the reflected power.

[0032] In the first aspect, an embodiment of the present invention provides a detection device. It mainly checks whether the semiconductor process chamber is in the ignition state by detecting whether there is a conduction current on the device in the semiconductor process chamber. When the semiconductor process chamber is full of plasma, the electrons or ions in the plasma will act on the device in the chamber to form a conduction current; if there is no plasma in the chamber, no conduction current is generated. Therefore, the state of the plasma can be accurately determined by measuring the conduction current through a simple structure.

[0033] Figure 11 is a schematic diagram of the structure of a detection device provided by an embodiment of the present invention. The detection device is applied to a semiconductor process chamber, and the semiconductor process chamber includes a focusing ring. The semiconductor process chamber is a chamber that can be used to generate plasma.

[0034] like Figure 1 As shown, the detection device includes a conduction current detection unit 1 and a ignition state determination unit 2. The conduction current detection unit 1 is in contact with the focus ring of the semiconductor process chamber, and is used to detect whether there is a conduction current in the focus ring. Specifically, it is possible to directly detect whether there is a conduction current in the focus ring, for example, by using a device capable of detecting current for detection; it is also possible to indirectly detect whether there is a conduction current in the focus ring, by detecting one or several parameters of an object related to the focus ring to detect whether there is a conduction current in the focus ring, wherein the one or several parameters have a causal relationship with the conduction current in the focus ring. For example, an object is connected to the focus ring through a wire, and when there is a conduction current in the focus ring, there is a current in the object and a voltage can be generated, then it can be determined whether there is a conduction current in the focus ring by detecting whether there is a current and / or whether a voltage is generated in the object. The ignition state determination unit 2 is used to determine whether the semiconductor process chamber is in the ignition state according to the detection result of the conduction current detection unit. Specifically, when there is a conduction current in the focus ring, the semiconductor process chamber is in the ignition state; when there is no conduction current in the focus ring, the semiconductor process chamber is not in the ignition state. When plasma exists in the semiconductor process chamber, that is, when the semiconductor process chamber is in the ignition state, electrons or ions in the plasma will bombard the focus ring, thereby, there is a conduction current in the focus ring. Therefore, it can be determined whether the semiconductor process chamber is in the ignition state by determining whether there is a conduction current in the focus ring.

[0035] Through the above technical scheme, it is detected whether there is a conduction current in the focusing ring, and whether the semiconductor process chamber is in a ignition state is determined based on the detection result, thereby realizing the detection of the ignition state in the semiconductor process chamber; in the detection, there is no need to set a reference threshold, and whether the semiconductor process chamber is in a ignition state is directly determined based on the detection result, thereby avoiding dependence on the reference threshold and misjudgment due to inappropriate reference threshold setting; in the detection, there is no need to rely on expensive spectrometer equipment to detect spectral intensity, thereby reducing costs.

[0036] Optionally, in an embodiment of the present invention, the conduction current detection unit may include a wire, a wire fixing unit and an electrical signal detection unit. The wire fixing unit is connected to the wire and contacts the focus ring, and is used to fix the wire to the focus ring and transmit the conduction current to the wire when there is a conduction current in the focus ring. For example, the wire fixing unit may be a metal screw, a metal stud, a metal rivet, etc., and any object that can fix the wire to the focus ring and can conduct current is acceptable, and there is no limitation on this. Specifically, the wire may be a high temperature resistant wire, so that the detection device is more reliable and less prone to failure, and the detection device has a longer service life. The electrical signal detection unit is connected to the wire and is used to detect an electrical signal to determine whether there is a conduction current in the focus ring, wherein the electrical signal includes a current signal and / or a voltage signal. The electrical signal is generated based on the presence of a conduction current in the focus ring. When the electrical signal detection unit can detect the electrical signal, there is a conduction current in the focus ring; when the electrical signal is not detected, there is no conduction current in the focus ring. By checking the electrical signal to detect whether there is a conduction current in the focus ring, it is relatively simple and direct to detect whether there is a conduction current in the focus ring.

[0037] Optionally, in the case where the electrical signal includes a current signal, the electrical signal detection unit may be any current signal detection unit capable of detecting current, such as an ammeter. The current signal detection unit is used to detect whether there is a current signal on the wire, so as to detect whether there is a conduction current in the focus ring. Specifically, whether there is a conduction current in the focus ring is detected based on the value obtained by the current signal detection unit.

[0038] Optionally, in the case where the electrical signal includes a current signal, the electrical signal detection unit may include a resistor and any current signal detection unit capable of detecting current. For example, the current signal detection unit may be an ammeter connected to the resistor for detecting whether there is current in the resistor so as to detect whether there is a conduction current in the focusing ring.

[0039] Optionally, in the case where the electrical signal includes a voltage signal and a current signal, the electrical signal detection unit may include a voltage-dividing resistor, a current signal detection unit and a voltage signal detection unit. Among them, the voltage-dividing resistor includes one or more resistors. The current signal detection unit is connected to a resistor in the voltage-dividing resistor to detect whether there is a current signal in the resistor. The voltage signal detection unit detects the voltage signal related to the voltage-dividing resistor. For example, it may be a voltage signal detected at both ends of the voltage-dividing resistor. In the case where the voltage-dividing resistor includes multiple resistors, it may be a voltage signal of some resistors (one or more) among the multiple resistors included. Whether there is a conduction current in the focusing ring is detected by whether the current signal detection unit can detect the current signal and whether the voltage signal detection unit can detect the voltage signal. Whether there is a conduction current in the focusing ring is detected based on both the current signal and the voltage signal, thereby improving the reliability of the detection.

[0040] Optionally, in the case where the electrical signal includes a voltage signal, the electrical signal detection unit may include a voltage divider resistor and a voltage signal detection unit, wherein the voltage signal detection unit may be any device capable of detecting voltage, such as a voltmeter or an oscilloscope. The voltage divider resistor includes one or more resistors and plays a role of voltage division. The voltage signal detection unit detects a voltage signal related to the voltage divider resistor. For example, it may be a voltage signal detected across the voltage divider resistor; in the case where the voltage divider resistor includes multiple resistors, it may be a voltage signal of some resistors (one or more) among the multiple resistors included. Whether there is a conduction current in the focusing ring is detected by whether the voltage signal detection unit can detect the voltage signal. In the case where the voltage divider resistor includes multiple resistors, if the voltage signal detection unit detects the voltage signal of some resistors among the multiple resistors, the requirements for the voltage signal detection unit can be reduced, thereby reducing the cost.

[0041] Optionally, in an embodiment of the present invention, the voltage-dividing resistor includes a first resistor and a second resistor, the resistance of the first resistor is greater than the resistance of the second resistor, and the voltage signal detection unit is configured to detect the voltage signal across the second resistor. Selecting to detect a voltage signal with a smaller resistance reduces the requirements for the voltage signal detection unit and reduces the cost. Optionally, in an embodiment of the present invention, the ratio of the first resistor to the second resistor can be determined according to the specific circumstances, for example, it can be 10:1. Optionally, in an embodiment of the present invention, the value of the first resistor is 10-100MΩ, and the value of the second resistor is 1-10MΩ.

[0042] Optionally, in an embodiment of the present invention, the conduction current detection unit may further include: an isolation unit for isolating the voltage-dividing resistor from the external environment so that the voltage signal detected by the voltage signal detection unit is only generated due to the conduction current in the focus ring. By providing the isolation unit, it is ensured that the voltage signal detected by the voltage signal detection unit is generated due to the conduction current in the focus ring, thereby improving the reliability of the detection device.

[0043] Optionally, in an embodiment of the present invention, the isolation unit may include an insulating isolation kit and a metal grounding shell. The wire passes through the insulating isolation kit and is connected to the voltage divider resistor and the voltage signal detection unit; the metal grounding shell surrounds the voltage divider resistor, and the insulating isolation kit isolates the wire and the metal grounding shell. Optionally, the number of insulating isolation kits can be determined according to the specific situation, as long as the isolation of the voltage divider resistor can be guaranteed. By providing the insulating isolation kit and the metal grounding shell, it is convenient to connect the wire and the voltage divider resistor and better isolate the voltage divider resistor.

[0044] Optionally, in an embodiment of the present invention, the metal grounding shell is provided with a first through hole, the insulating isolation kit is installed in the first through hole, and the voltage divider resistor is located in the space formed by the insulating isolation kit and the metal grounding shell. The position of the first through hole on the metal grounding shell can be determined according to the specific situation, and there is no limitation on this. In addition, the shape of the metal grounding shell is not limited, as long as it can meet the technical concept of the embodiment of the present invention. For example, the metal grounding shell can be a rectangular, square or tubular structure. In the case where the metal grounding shell is a tubular structure, it can include two first through holes, and the two first through holes are respectively located at the two ends of the tubular structure.

[0045] The following combines 2 to Figure 7 An exemplary introduction is given to a detection device for detecting a ignition state in a semiconductor process chamber provided in an embodiment of the present invention.

[0046] Figure 2 Schematic diagram of a semiconductor process chamber structure with a detection device provided by another embodiment of the present invention. Figure 2 The semiconductor process chamber structure shown is a typical CCP structure. Figure 2As shown, it includes an air intake pipeline 3, an SHD4, a first lifting structure 5, an inner liner 6, a focusing ring 8, a machine housing 13, a feeding column 14, a dual-frequency fixed matcher 15, a high-frequency power supply 16, a low-frequency power supply 17, an ESC 18, a grounding ring 19, an isolation ring 20, a base liner 21, an insulating ring 22 and a second lifting structure 23. The air inlet pipeline 3 is connected to the SHD 4; the first lifting structure 5 and the second lifting structure 23 are in contact with the machine housing 13 and the liner 6 respectively; the liner 6 is connected to the insulating ring 22; the liner 6 connects the SHD 4 and the base 21; the base 21 contacts the focusing ring 8 and the grounding ring 19; the isolation ring 20 contacts the focusing ring 8 and the grounding ring 19, and isolates the grounding ring 19 and the ESC 18; the ESC 18 contacts the focusing ring 8, and the ESC 18 is used to carry the wafer 7; the feeding column 14 contacts the ESC 18 and the dual-frequency fixed matcher 15; the dual-frequency fixed matcher 15 contacts the machine housing 13, the feeding column 14, the high-frequency power supply 16 and the low-frequency power supply 17. The SHD 4 is generally made of semiconductor material; the first lifting structure 5 and the second lifting structure 23 are used to lift the liner 6; the material of the liner 6 can be a dielectric or a semiconductor material; the focusing ring 8 is made of a semiconductor material; the high-frequency power supply 16 is referred to as HF, such as 60MHz, 40.68, 27.12MHz, etc.; the low-frequency power supply 17 is referred to as LF, such as 2MHz, 800kHz, 400kHz, etc.; the bottom liner 21 is a grid structure, through which the dry pump can extract the gas and by-products inside the chamber to ensure the stability of the gas pressure inside the chamber during the process; in addition, the bottom liner 21 meets certain aspect ratio requirements to ensure that the plasma can be annihilated; the grounding ring 19 is made of metal; the isolation ring 20 is made of a dielectric, generally quartz or ceramic.

[0047] During the process, the gas enters the chamber evenly through the gas inlet pipe 3 and SHD 4, and the high-frequency power and the low-frequency power are transmitted to the semiconductor process chamber through the dual-frequency fixed matcher 15, the feed column 14, and the ESC 18 to achieve the purpose of exciting plasma.

[0048] Figure 3 FIG. 1 is a schematic diagram of the composition of a detection device for detecting the ignition state in a semiconductor process chamber provided by another embodiment of the present invention. Figure 3As shown, the detection device includes a metal screw 201, a wire 202, an insulating isolation kit 203 (two), a metal grounding shell 9, a first resistor 10, a second resistor 11 and a collection unit 12. Among them, the collection unit 12 is used to obtain the voltage signal at both ends of the second resistor. Specifically, the collection unit 12 is an oscilloscope. The metal grounding shell 9 is a tubular structure with first through holes at both ends. The two insulating isolation kits 203 are respectively installed in the first through holes at both ends of the metal grounding shell 9. The first resistor 10 and the second resistor 11 are located in the space formed by the metal grounding shell 9 and the insulating isolation kit 203. The wire 202 passes through one insulating isolation kit 203 to be connected to the first resistor 10, and passes through another insulating isolation kit 203 to be connected to the collection unit 12. The detection device also includes a ignition state determination unit (not shown). In addition, the first resistor 10 is a large resistor, generally with a resistance of 10-100MΩ, and is used as a voltage divider; the wire 202 is a high-temperature resistant wire, one end of which is connected to the first resistor 10, and the other end is connected to the metal screw 201; the metal screw 201 is connected to the focusing ring 8; the second resistor 11 is a small resistor, generally with a resistance of 1-10MΩ; it is generally required that the resistance of the second resistor 11 is in a 1:10 relationship with the resistance of the first resistor 10 to ensure that the large resistor bears most of the voltage.

[0049] The installation side view of the metal grounding shell 9 and the insulation isolation kit 203 is as shown in FIG. Figure 4 As shown, the insulating isolation kit 203 can directly isolate the metal grounding shell 9 from the wire 202 .

[0050] The acquisition unit 12 is a detection signal acquisition device of a DC bias, and is used to detect the voltage signal across the second resistor 11. For example, the acquisition unit 12 may be an oscilloscope. When no RF power is loaded, there is no plasma inside the semiconductor process chamber, and no conduction current passes through the loop. Then, the voltage value collected by the acquisition unit 12 is 0 (see Figure 7 (b)). As the RF power is loaded to 200W, there is plasma in the chamber, and the intensity of the Ar707 characteristic spectrum line (the characteristic peak corresponding to the wavelength of the Ar atom of 707nm) is also significantly enhanced, as shown in Figure 2. Figure 7 At the same time, the electrons or ions in the plasma will bombard the focusing ring 8, and the conduction current will be transmitted to the metal screw 201 through the focusing ring. Then, the voltage value of the second resistor 11 collected by the collection unit 12 will be negative (because the mass of electrons is much smaller than the mass of ions, electrons will reach the focusing ring 8 faster than ions, forming an electron conduction current. The electron conduction current will cause the voltage signal collected on the second resistor 11 to be negative, see Figure 7(b)) and then determine that the chamber is in the ignition state. If the ignition fails, there is no plasma in the chamber, that is, no conduction current passes through the loop, then the voltage value collected by the acquisition unit 12 is still 0, and the chamber is not in the ignition state, that is, the ignition is abnormal. The ignition state determination unit determines whether the semiconductor process chamber is in the ignition state according to the voltage value of the acquisition unit 12. When the voltage value collected by the acquisition unit 12 is 0, the ignition state determination unit determines that the semiconductor process chamber is not in the ignition state; when the voltage value collected by the acquisition unit 12 is not 0, the ignition state determination unit determines that the semiconductor process chamber is in the ignition state.

[0051] The schematic diagram of installing the detection device provided by the embodiment of the present invention in the semiconductor process chamber is as follows: Figure 5a , Figure 5b and Figure 6 As shown. Among them, Figure 5a is a bottom view of the focus ring 8, showing the installation position of the metal screw 201; Figure 5a It is a cross-sectional view, from which it can be seen that the metal screw 201 and the focusing ring 8 are in close contact, and the metal screw 201 and the high-temperature wire 202 are conductive. Figure 6 This is a partial enlarged view of the detection device installed in the semiconductor process chamber. A through hole is drilled inside the grounding ring 19 to ensure that the wire 202 can pass smoothly. In addition, the surface of the grounding ring 19 and the inner surface of the through hole are insulated, and the outside of the wire 202 is a high-temperature insulation layer, so the wire 202 and the grounding ring 19 are not conductive.

[0052] The technical solution provided by the embodiment of the present invention directly receives the conduction current signal formed after the plasma is ignited, and detects whether the semiconductor process chamber is in the ignition state by detecting the voltage signal, without the need to convert the optical signal into the electrical signal, and the device is simpler and the cost is lower. The detection device provided by the embodiment of the present invention has low cost and simple operation, and can effectively monitor whether the semiconductor process chamber is in the ignition state without complicated settings, thereby avoiding static matching in the process. The technical solution provided by the embodiment of the present invention directly receives the conduction current signal formed after the plasma is ignited, and does not require expensive equipment such as a spectrometer, and the device is simpler and the cost is lower; whether the ignition is successful or not can be determined by detecting the presence or absence of the conduction current signal, without relying on the set threshold. The technical solution provided by the embodiment of the present invention monitors the ignition state in the chamber by detecting the voltage signal existing due to the conduction current, and can more directly, accurately and effectively monitor the ignition state in the chamber, avoiding static matching in the process, and avoiding process failure caused by static matching.

[0053] Figure 8 It is a logical schematic diagram of a detection device provided in another embodiment of the present invention.

[0054] In step S80, when the process starts, the gas required in the process is first introduced, and the swing valve is controlled to the corresponding gas pressure. In step S81, the RF power supply is loaded. In step S82, it is determined whether the voltage value collected by the acquisition unit 12 is equal to 0. If the voltage value is equal to 0, it indicates that there is no plasma inside the semiconductor process chamber, and the chamber may be in a static matching state, that is, the semiconductor process chamber is in a ignition state, and step S84 is executed. Otherwise, the chamber is in a normal process state, and step S83 is executed. In step S83, the process flow is carried out normally. In step S84, the RF is turned off, and the swing valve is controlled to increase the pressure inside the chamber. After executing step S84, step S81 is executed to reload the RF. Then step S81 is executed to determine whether the detected voltage value is 0 again; this cycle is repeated until the voltage value is less than 0, the chamber process state is normal, the chamber is in a ignition state, and the process flow is completed normally.

[0055] The technical solution provided by the embodiment of the present invention can detect when the static matching (ignition failure) is in progress, and avoid the occurrence of the static matching situation through process optimization, thereby ensuring the normal completion of the process flow.

[0056] In summary, the technical solution provided by the embodiment of the present invention aims to provide a method for avoiding static matching of the chamber, and proposes a detection device to determine the plasma ignition state; when static matching is detected, the occurrence of static matching is avoided by process optimization.

[0057] In a second aspect, an embodiment of the present invention further provides a semiconductor process chamber, which comprises: a cavity and a focusing ring located in the cavity; and the detection device described in the above embodiment, wherein the conduction current detection unit in the detection device is electrically connected to the focusing ring.

[0058] Optionally, in an embodiment of the present invention, the conduction current detection unit includes a wire, a wire fixing unit and an electrical signal detection unit, and the semiconductor process chamber further includes: a carrier plate, located in the cavity, having a bearing surface, the bearing surface is used to carry the wafer, and the focus ring surrounds the outside of the bearing surface; a grounding ring, located in the cavity, in contact with the focus ring, the wire passes through the second through hole inside the grounding ring and is connected to the wire fixing unit, and the wire fixing unit is in contact with the focus ring. The carrier plate can be an electrostatic chuck.

[0059] Optionally, in an embodiment of the present invention, the conduction current detection unit further includes an isolation unit, the isolation unit includes an insulating isolation kit and a metal grounding shell, the side wall of the cavity is provided with a third through hole, and the metal grounding shell is arranged in the third through hole.

[0060] Optionally, in an embodiment of the present invention, the semiconductor process chamber may further include an adjustment unit. The adjustment unit is used to control the pressure in the semiconductor process chamber to increase when the semiconductor process chamber is not in the ignition state until the semiconductor process chamber is in the ignition state. It should be noted that in an embodiment of the present invention, when it is detected that the semiconductor process chamber is not in the ignition state, the pressure in the semiconductor process chamber may be controlled to increase, and then it is detected whether the semiconductor process chamber is in the ignition state; when it is detected again that the semiconductor process chamber is not in the ignition state, the pressure is continued to be controlled to increase, and then it is detected again whether the semiconductor process chamber is in the ignition state; ...; this cycle is repeated until the semiconductor process chamber is in the ignition state. By setting the adjustment unit, when the semiconductor process chamber is not in the ignition state, the state in the semiconductor process chamber can be optimized to make it in a normal process state.

[0061] Optionally, in an embodiment of the present invention, before controlling to increase the pressure in the semiconductor process chamber, the radio frequency for exciting and generating plasma may be controlled to be turned off first to enhance stability.

[0062] In a third aspect, an embodiment of the present invention provides a detection method.

[0063] Fig. 9 FIG. 1 is a flow chart of a detection method for detecting the ignition state in a semiconductor process chamber provided by another embodiment of the present invention. Applied to a semiconductor process chamber, the semiconductor process chamber includes a focusing ring. Fig. 9 As shown, the detection method includes the following contents.

[0064] In step S90, it is detected whether there is a conduction current in the focus ring of the semiconductor process chamber. In step S91, it is determined whether the semiconductor process chamber is in a ignition state according to the detection result.

[0065] Optionally, in an embodiment of the present invention, the detection method further includes the following: When the semiconductor process chamber is not in the ignition state, controlling the pressure in the semiconductor process chamber to increase until the semiconductor process chamber is in the ignition state.

[0066] The specific working principle and benefits of the detection method provided in the embodiment of the present invention are similar to the specific working principle and benefits of the detection device provided in the embodiment of the present invention, and will not be repeated here.

[0067] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] The above embodiments only express several implementation methods of this specification, and the descriptions are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of this specification, which all belong to the protection scope of this specification. Therefore, the protection scope of the patent of this specification shall be based on the attached claims.

Claims

1. A detection device, characterized in that: Applied to a semiconductor process chamber, the semiconductor process chamber includes a focusing ring, and the detection device includes: a conduction current detection unit, in contact with the focus ring, for detecting whether there is a conduction current in the focus ring; and The ignition state determination unit is used to determine whether the semiconductor process chamber is in the ignition state according to the detection result of the conduction current detection unit.

2. The detection device according to claim 1, characterized in that: The conduction current detection unit comprises: wire; a wire fixing unit connected to the wire and in contact with the focus ring, configured to fix the wire to the focus ring and transmit the conduction current to the wire when the conduction current exists in the focus ring; and An electrical signal detection unit is connected to the wire and is used to detect an electrical signal to determine whether the conduction current exists in the focusing ring, wherein the electrical signal includes a current signal and / or a voltage signal.

3. The detection device according to claim 2, characterized in that: The electrical signal includes a voltage signal, and the electrical signal detection unit includes: A voltage dividing resistor connected to the wire; and The voltage signal detection unit is used to detect the voltage signal related to the voltage dividing resistor.

4. The detection device according to claim 3, characterized in that: The voltage-dividing resistor includes a first resistor and a second resistor, the resistance of the first resistor is greater than the resistance of the second resistor, and the voltage signal detection unit is configured to detect a voltage signal across the second resistor.

5. The detection device according to claim 3 or 4, characterized in that: The conduction current detection unit further includes: The isolation unit is used to isolate the voltage-dividing resistor from the external environment so that the voltage signal detected by the voltage signal detection unit is only generated due to the conduction current in the focusing ring.

6. The detection device according to claim 5, characterized in that: The isolation unit comprises: an insulating isolation kit, through which the wire passes to be connected to the voltage dividing resistor and the voltage signal detection unit; and A metal grounding shell surrounds the voltage dividing resistor, and the insulating isolation kit isolates the wire and the metal grounding shell.

7. The detection device according to claim 6, characterized in that: The metal grounding shell is provided with a first through hole, the insulating isolation kit is installed in the first through hole, and the voltage dividing resistor is located in a space formed by the insulating isolation kit and the metal grounding shell.

8. A semiconductor process chamber, characterized in that: include: a cavity and a focusing ring located in the cavity; as well as The detection device according to any one of claims 1 to 7, wherein the conduction current detection unit in the detection device is electrically connected to the focusing ring.

9. The semiconductor process chamber according to claim 8, characterized in that: The conduction current detection unit includes a wire, a wire fixing unit and an electrical signal detection unit, and the semiconductor process chamber also includes: A carrier plate is located in the cavity and has a carrier surface, the carrier surface is used to carry the wafer, and the focusing ring surrounds the outer side of the carrier surface; A grounding ring is located in the cavity and contacts the focusing ring. The wire passes through a second through hole in the grounding ring and is connected to the wire fixing unit. The wire fixing unit contacts the focusing ring.

10. The semiconductor process chamber according to claim 9, characterized in that: The conduction current detection unit further includes an isolation unit, which includes an insulating isolation kit and a metal grounding shell. A third through hole is provided on the side wall of the cavity, and the metal grounding shell is arranged in the third through hole.

11. A detection method, characterized in that: Applied to a semiconductor process chamber, the semiconductor process chamber includes a focusing ring, and the detection method includes: detecting whether there is a conduction current in the focusing ring; and According to the detection result, it is determined whether the semiconductor process chamber is in a ignition state.

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