TW201906036A - Processing chamber air detection system and operation method thereof - Google Patents

Abstract

A chamber detection system is provided, including a chamber, a vacuuming unit, an exhaust pipe, a connection pipe, and an air detector. The camber is configured to perform a chemical vapor deposition process. The exhaust pipe connected to the chamber and the vacuuming unit, and the connection pipe communicates with the exhaust pipe. The air detector is disposed on the connecting pipe and configured to detect oxygen in the air from the camber.

Description

 Process chamber gas detection system and operation method thereof  

The present disclosure relates to a process chamber gas detection system and a method of operating the same, and more particularly to a detection system having a gas detector and a method of operating the same.

In the semiconductor industry, chemical vapor deposition (CVD) is often used to grow thin films. A typical CVD process exposes a wafer (substrate) to one or more different precursors, chemically and/or chemically decomposed on the surface of the substrate to produce a film to be deposited. During the reaction, different by-products are usually produced concomitantly, so that they are carried away with the gas flow by pumping the reaction chamber so that it does not remain in the cavity. The current CVD process, which is often used in a low pressure environment CVD process, Low Pressure Chemical Vapor Deposition (LPCVD), reduces the pressure to reduce unnecessary gas phase reactions, and increases the uniformity of the film on the wafer. Sex.

With the evolution of semiconductor technology, the quality requirements for the products in the process are relatively improved, so the accuracy of the pressure control in the cavity and the tightness between the cavity and the pipeline are relatively strict. However, because of the long-term use of such components, the degree of adhesion of the cavity, line or cavity to the pipeline may result in degradation and cracking which may result in a decrease in the accuracy and quality of the overall process. Therefore, in order to improve the quality of the process, it is increasingly important to provide accurate and immediate detection mechanisms on each component to determine whether the component has cracks or leaks.

A leak detection system generally used to detect a low pressure chemical vapor deposition (LPCVD) reaction furnace. A pressure detector is often used to detect the pressure inside the reactor furnace. After the pressure is maintained for a period of time, if there is a pressure change during the time, the leak rate can be calculated according to the pressure change/the time, and then it is known whether there is atmospheric intrusion. However, the pressure detector installed on the detection system may have a detection error on the gas pressure in the furnace, so that when a small leak detection is to be performed (for example, the gas pressure in the furnace is less than 10 ^-4 mbar), the measurement occurs. Unacceptable circumstances can not reflect the actual leakage situation.

The invention provides a process chamber gas detecting system, which mainly comprises a cavity, a pumping unit, an exhaust pipe, a connecting pipe and a gas detector. The cavity system is configured to perform a chemical vapor deposition process, the exhaust pipe is connected to the cavity and the pumping unit, the connecting pipe is connected to the exhaust pipe, and the gas detector is disposed on the connecting pipe, and is used for detecting the gas in the cavity. Oxygen content. When the pumping unit extracts the gas in the chamber and the gas passes through the exhaust pipe and the connecting pipe, the gas detector detects whether the gas contains the oxygen.

In one embodiment, when the gas detector detects the oxygen content of the gas, the gas pressure in the chamber is less than 1 x 10 ^-8 mbar.

In one embodiment, the gas detector is at least 25 meters away from the cavity.

In one embodiment, when the gas detector detects the oxygen content of the gas, the temperature in the chamber is greater than 600 ° C.

The invention provides a method for operating a process chamber gas detecting system, comprising: providing an exhaust pipe connecting a cavity and a pumping unit, wherein the cavity is configured to perform a chemical vapor deposition process; providing a connecting pipe and connecting the pumping a gas pipe; a first valve member is disposed on the air suction pipe; a second valve member and a gas detector are disposed on the connecting pipe; the first valve member is opened, and the air suction unit performs a gas on a gas in the cavity Pumping once; opening the second valve member to allow gas to flow from the suction pipe to the connecting pipe; and detecting the oxygen content in the gas by the gas detector.

In one embodiment, the first evacuation described above is performed such that the pressure within the chamber is less than 10 ^-8 mbar.

In one embodiment, after performing the foregoing first pumping step and before the step of opening the second valve member, an inert gas is applied to the chamber, and the pumping unit performs a second operation on the gas in the chamber. Pumping down.

In one embodiment, after performing the aforementioned first pumping step and before the step of opening the second valve member, the first valve member is closed and an inert gas is applied to the chamber, and the chamber is maintained under pressure 5- After 10 minutes, the first valve member is then opened and the pumping unit performs a second pumping of the chamber.

In one embodiment, the gas detector is disposed at least 25 meters away from the cavity.

In an embodiment, the operation method of the detecting system further comprises: setting a trap on the air suction pipe, and the trap is closer to the cavity than the gas detector, and when the air pumping unit performs the gas on the gas in the cavity The trap filters the particles in the gas during a single pumping.

10‧‧‧Pumping unit

30‧‧‧ gas detector

50‧‧‧ Controller

70‧‧‧Capture

301-307‧‧‧Steps

401-404‧‧‧Steps

C‧‧‧ cavity

G‧‧‧ Intake pipe

P‧‧‧ Pressure Detector

T1‧‧‧Exhaust pipe

T2‧‧‧ connection tube

V1‧‧‧ first valve

V2‧‧‧Second valve

1 is a schematic view showing a process chamber gas detecting system according to an embodiment of the present invention.

2 is a schematic view showing a process chamber gas detecting system according to another embodiment of the present invention.

Figure 3 is a flow chart showing the operation of the card processing chamber gas detecting system in accordance with an embodiment of the present invention.

Figure 4 is a flow chart showing the operation of the process chamber gas detecting system of another embodiment of the present invention.

The process chamber gas detecting system of the embodiment of the present invention will be described below. However, it will be readily understood that the embodiments of the present invention are susceptible to many specific embodiments of the invention and can The specific embodiments disclosed are merely illustrative of the invention, and are not intended to limit the scope of the invention.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning meaning It will be understood that these terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the relevant art and the context or context of the present disclosure, and should not be in an idealized or overly formal manner. Interpretation, unless specifically defined herein.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a process chamber gas detecting system according to an embodiment of the present invention. As shown, the process chamber gas detection system can be configured in a semiconductor factory and includes a cavity C, wherein the cavity C is used, for example, in a semiconductor process using Chemical Vapor Deposition (CVD). A film growth reactor in which one or more wafers are exposed to one or more different precursors and chemically reacted or/and chemically decomposed on the surface to produce a film to be deposited. The reaction chamber of Low Pressure Chemical Vapor Deposition (LPCVD) is used, and the reaction temperature is carried out at a high temperature (for example, 600 to 1000 ° C). When film deposition is performed, the gas pressure in the cavity C is, for example, lowered to about 100 mbar or less, so that the reaction proceeds at a low pressure, so that the deposited film has better step coverage capability and thickness uniformity. . A common CVD deposition material is, for example, silicon dioxide, silicon Nitride, polysilicon or a metalloid telluride.

Please refer to FIG. 1 . The process chamber gas detection system includes a pumping unit 10 , a gas detector 30 , an exhaust pipe T1 , a connecting pipe T2 , and a first valve in addition to the cavity C. A piece V1, a second valve member V2 and a controller 50. The exhaust pipe T1 communicates with the cavity C and the pumping unit 10, so that the pumping unit 10 can pump the cavity C by the exhaust pipe T1, and the connecting pipe T2 having a U-shaped structure communicates with the exhaust pipe T1, so that the cavity The gas in the body C can flow to the connecting pipe T2 via the exhaust pipe T1. The first and second valve members V1, V2 can control the gas flow rate. When the first valve member V1 is opened, the pumping unit 10 can be started to pump the chamber C; when the first and second valve members V1, V2 When it is opened, the gas can flow from the exhaust pipe T1 through the connecting pipe T2, and the gas is taken out through the pumping unit 10. In addition, the pressure detector P is also connected to the exhaust pipe T1 and located between the cavity C and the first valve member V1 for detecting the gas pressure in the cavity C.

In the present embodiment, since the low-pressure chemical deposition reaction in the aforementioned cavity C is accompanied by the generation of by-products such as hydrogen, water, silicon tetrachloride or hydrogen chloride ( Hydrochloride, HCl), the chamber C can be evacuated by the pumping unit 10 to discharge the by-products from the chamber C, and the by-products can be discharged (for example, discharged to an exhaust gas washing system) to The purpose of semiconductor pollutant prevention and control.

As can be seen from Fig. 1, a gas detector 30 is provided at one end of the connecting tube T2, which is, for example, an oxygen detector, which can be used to detect the oxygen content of the gas in the cavity C, thereby analyzing the cavity. Whether C is caused by cracks or cavity C and the pipeline are not tightly coupled, and air or other gas in the atmospheric environment enters the cavity C. In detail, in the present embodiment, when a continuous silicon film is grown on the substrate in the cavity C of the CVD process, the chemical used does not contain oxygen, and if excessive oxygen is present in the cavity In the body C, a film which is grown on the substrate may be caused to have a disordered ruthenium oxide film. Therefore, the gas detector 30 can detect whether the gas in the cavity C contains oxygen, and thus can help determine whether the cavity C, the exhaust pipe T1 or the connecting pipe T2 has a crack and leaks or invades the atmosphere. .

With regard to the gas detector 30 described above, it converts the substance to be tested (oxygen) in the gas into an appropriate electrical signal (such as voltage, current or resistance) for metering. For example, a preset value may be input in the gas detector 30, and the gas detector 30 may detect a specific gas content to obtain a measured value, and compare it with the preset value to determine Whether or not this specific gas is contained. Subsequently, the gas detector 30 can transmit information to the controller 50 to cause the controller 50 to notify the process operator to know what the current gas detector 30 has detected.

The flow of the instant detection of the aforementioned cavity C will be described in detail below. First, an intake pipe G delivers the gas to be reacted to the cavity C to react with one or a plurality of substrates (or wafers) in the cavity C to perform a CVD process. Next, the pumping unit 10 is evacuated to the cavity C by opening the first valve member V1 to remove by-products generated in the process, and the gas pressure in the cavity C is drawn to a low pressure environment (for example, less than 10 ^{- At 8} mbar, the second valve member V2 is opened to allow gas to flow from the exhaust pipe T1 to the connecting pipe T2, and the gas detector 30 detects the gas flowing out of the cavity C to detect the gas. Whether the gas contains oxygen. At this time, if it is detected that the current electrical signal is higher than the preset electrical signal to a predetermined extent, it is determined that the external gas intrusion occurs in the cavity C or the pipeline. In other words, in the low-pressure environment, the gas detector 30 can detect the presence or absence of any tiny leaks in the cavity C performing the CVD process, thereby enabling timely processing and allowing the cavity to be processed. The CVD process in C can be maintained at a high quality level.

It should be understood that there is a distance between the gas detector 30 and the cavity C. In the embodiment, the distance is greater than 25 meters. Since the cavity C is a high temperature reaction furnace of a CVD process, the operating temperature is about 600 to 1000 ° C. If the gas detector 30 is placed too close to the cavity C, the gas detector 30 may be destroyed or failed due to high temperature. Therefore, by providing the gas detector 30 at least 25 meters away from the cavity C, the instantaneous monitoring of the cavity C in the CVD process can be stably and safely achieved.

2 is a schematic view of a process chamber gas detecting system according to another embodiment of the present invention, which is mainly different from the process chamber gas detecting system (FIG. 1) in the process chamber gas in this embodiment. The detection system further includes a trap 70 disposed on the exhaust pipe T1 for adsorbing, filtering, and capturing particles or dust in the gas extracted through the pumping unit 10. It is worth noting that the trap 70 is disposed upstream of the gas detector 30 and is closer to the cavity C than the gas detector 30. In this way, before the gas flows to the gas detector 30, the particles can be captured through the trap 70, so that the gas detector 30 can perform oxygen detection more effectively, and the clogging of the exhaust pipe T1 can be reduced.

According to the foregoing embodiments, the present invention also provides a method for operating a process chamber gas detecting system. As shown in FIG. 3, an exhaust pipe T1 is first provided to connect a cavity C and a pumping unit 10, And a connecting pipe T2 is connected to the exhaust pipe T1 (step 301), wherein the cavity C can be used, for example, to perform a CVD process; then, a first valve member V1 is disposed on the exhaust pipe T1, and a second valve member V2 is disposed. And a gas detector 30 is connected to the tube T2 (step 302), wherein the gas detector 30 is disposed at least 25 meters away from the cavity C. Subsequently, the first valve member V1 is opened, and the pumping unit 10 performs the first pumping of the chamber C by the exhaust pipe T1, so that the gas pressure in the chamber C is lower than 10 ^-8 mbar (step 303). Then, the first valve member V1 is closed (step 304), and an inert gas is applied to the cavity C (for example, helium gas is applied through an intake pipe G) and the gas pressure in the cavity C is maintained for a predetermined time (for example, 5- 10 minutes) (step 305); then, the first valve member V1 is opened and the pumping unit 10 performs a second pumping of the chamber C (step 306), and then the gas pressure in the chamber C is lower than 10 ^-8 mbar and open the second valve member V2, so that the gas in the cavity C flows from the exhaust pipe T1 through the connecting pipe T2, so that the gas detector 30 detects the oxygen content in the gas (step 307). In this way, the gas detector 30 can detect the oxygen content in the gas to determine whether the cavity C or the pipeline is slightly damaged or leaked, so that the CVD process can be stopped and properly processed to avoid excessive quality formation. Product produced.

By the step 304 of applying an inert gas to the chamber C as described above, the gas in the chamber C can be efficiently flowed so that the second pumping (step 306) can be performed more efficiently. Maintaining the gas pressure in the cavity C for a predetermined time (step 305) allows the inert gas to have a sufficient time to be evenly distributed in the cavity C, so that the second pumping (step 306) can be performed more efficiently. In turn, the gas detector 30 determines the oxygen content in the gas to be more accurate. In addition, a trap 70 can also be provided on the exhaust pipe T1, wherein the position of the trap 70 is closer to the cavity C than the gas detector 30, and when the pumping unit 10 draws the cavity C, The particles in the gas are filtered through a trap 70.

However, in the operation method of another embodiment, the gas pressure of the holding cavity C in the foregoing step 305 may be omitted for a predetermined time, and the first and second valve members V1 and V2 are directly opened after the inert gas is applied. The gas in the cavity C flows from the exhaust pipe T1 to the connecting pipe T2, so that the gas detector 30 can detect the oxygen content in the gas.

In addition, the present invention further provides another method for operating the process chamber gas detecting system. As shown in FIG. 4, the main difference from the operation method in the foregoing FIG. 3 is that the first pumping of the chamber C is performed. (Step 403), and directly opening the second valve member V2 when the gas pressure in the chamber C is lower than 10 ^-8 mbar, so that the gas in the cavity C flows from the exhaust pipe T1 through the connecting pipe T2, so that the gas detection The detector 30 detects the oxygen content of the gas (step 404).

In summary, the present invention provides a process chamber gas detection system and a method for operating the same, the process chamber gas detection system mainly includes a cavity, a pumping unit, an exhaust pipe, a connecting pipe and a gas detection Device. The cavity system is configured to perform a chemical vapor deposition process, the exhaust pipe is connected to the cavity and the pumping unit, the connecting pipe is connected to the exhaust pipe, and the gas detector is disposed on the connecting pipe, and is used for detecting the gas in the cavity. Oxygen content. When the pumping unit performs pumping on the chamber, the gas pressure in the chamber is lower than 10 ^-8 mbar, at which time the gas flows from the exhaust pipe to the connecting pipe, and the gas detector performs detection on the gas. It is detected whether or not the gas contains the oxygen. In this way, the gas detector can be used to check whether there is a slight leakage in the cavity, so that the CVD process can be stopped in time and appropriate treatment can be performed to avoid excessive generation of defective products, thereby improving the process quality.

The ordinal numbers in the specification and the scope of the patent application, such as "first", "second", etc., have no sequential relationship with each other, and are only used to indicate that two different elements having the same name are distinguished.

The above-described embodiments are described in sufficient detail to enable those of ordinary skill in the art to practice the invention disclosed herein. Some changes and refinements may be made, so the scope of protection of this creation is subject to the definition of the patent application scope attached.

Claims (10)

 A process chamber gas detection system, comprising: a cavity configured to perform a chemical vapor deposition process; a pumping unit; an exhaust pipe connecting the cavity and the pumping unit; a connecting pipe connecting the pumping a gas detector; and a gas detector disposed on the connecting pipe, the gas detector detecting the gas when the pumping unit extracts a gas from the cavity through the exhaust pipe and the connecting pipe The oxygen content in the medium.   The detection system of claim 1, wherein when the gas detector detects the oxygen content of the gas, the gas pressure in the chamber is less than 1 x 10 ^-8 mbar.  The detection system of claim 1, wherein the gas detector is at least 25 meters away from the cavity.    The detection system of claim 1, wherein when the gas detector detects the oxygen content of the gas, the temperature in the cavity is greater than 600 °C.    A method for operating a process chamber gas detection system, comprising: providing an exhaust pipe connecting a cavity and a pumping unit, wherein the cavity is configured to perform a chemical vapor deposition process; providing a connecting pipe to connect the pumping a gas pipe; a first valve member is disposed on the air suction pipe; a second valve member and a gas detector are disposed on the connecting pipe; the first valve member is opened, and the air suction unit is in the cavity a gas performs a first pumping; opening the second valve member to flow the gas from the exhaust pipe to the connecting pipe; and detecting the oxygen content in the gas by the gas detector.   The method of operating the detection system of claim 5, wherein the first pumping is performed such that the pressure within the chamber is less than 10 ^-8 mbar.  The method of operating the detection system of claim 5, wherein an inert gas is applied to the cavity after the step of performing the first pumping and before the step of opening the second valve member, And causing the pumping unit to perform a second pumping of the gas in the chamber.    The method of operating the detection system of claim 5, wherein after the step of performing the first pumping and before the step of opening the second valve member, closing the first valve member and applying a An inert gas is introduced into the chamber, and the chamber is held under pressure for 5-10 minutes, after which the first valve member is opened and the pumping unit performs a second pumping of the chamber.    The method of operating a detection system according to claim 5, wherein the gas detector is disposed at least 25 meters away from the cavity.    The operating method of the detecting system of claim 5, wherein the operating method of the detecting system further comprises: setting a trap on the air suction pipe, and the trap is more than the gas detector Closer to the cavity, the trap filters particles in the gas when the pumping unit performs the first pumping of the gas in the chamber.