阅读说明：本技术 等离子体启辉的检测装置及方法、工艺腔室 (plasma glow starting detection device and method and process chamber ) 是由 叶华 刘红义 于 2018-06-08 设计创作，主要内容包括：本发明公开了一种等离子体启辉的检测装置、方法和工艺腔室。包括光电转换元件和控制单元,其中,光电转换元件的感光面用于与工艺腔室的出光侧对应,以检测工艺腔室内的光信号并将光信号转换为电信号后发送至控制单元；控制单元,用于接收电信号后与预设的临界启辉电信号进行比较,当电信号满足临界启辉电信号时,判定工艺腔室内的等离子体发生启辉。通过检测工艺腔室内的光信号并将光信号转换为电信号,之后根据电信号确定等离子体是否发生启辉。检测等离子体是否启辉的装置简单、有效,能够有效地降低检测等离子体启辉的成本。此外,还便于工艺开发人员进行预判,无需复杂的控制算法与数据处理,可以更好地进行推广应用。(The invention discloses a plasma glow starting detection device and method and a process chamber. The device comprises a photoelectric conversion element and a control unit, wherein a light sensing surface of the photoelectric conversion element is used for corresponding to a light outlet side of a process chamber so as to detect an optical signal in the process chamber, convert the optical signal into an electrical signal and send the electrical signal to the control unit; and the control unit is used for receiving the electric signal, then comparing the electric signal with a preset critical starting electric signal, and judging that the plasma in the process chamber is started when the electric signal meets the critical starting electric signal. The plasma is started or not according to the electrical signal after the optical signal in the process chamber is detected and converted into the electrical signal. The device for detecting whether the plasma is started is simple and effective, and the cost for detecting the plasma is effectively reduced. In addition, the method is convenient for process developers to prejudge, does not need complex control algorithms and data processing, and can be better popularized and applied.)

1. a plasma glow detection device is characterized by comprising a photoelectric conversion element and a control unit, wherein,

The light sensing surface of the photoelectric conversion element is used for corresponding to the light emitting side of the process chamber so as to detect an optical signal in the process chamber, and the photoelectric conversion element can convert the optical signal into an electrical signal and then send the electrical signal to the control unit;

and the control unit is used for receiving the electric signal, comparing the electric signal with a preset critical starting electric signal, and judging that plasma in the process chamber is started when the electric signal meets the critical starting electric signal.

2. The plasma ignition detection apparatus according to claim 1,

The control unit is further configured to determine the plasma ignition intensity according to the electrical signal, wherein the magnitude of the electrical signal is in positive correlation with the plasma ignition intensity.

3. The apparatus for detecting plasma ignition according to claim 1, wherein the photoelectric conversion element includes a solar cell.

4. A plasma ignition detection apparatus according to any one of claims 1 to 3, further comprising:

and the light shielding member is used for placing the photoelectric conversion element, and shields other surfaces except the light sensing surface in the photoelectric conversion element.

5. a plasma ignition detection apparatus as claimed in any one of claims 1 to 3, wherein the electrical signal is an analog electrical signal, the critical ignition electrical signal is a critical ignition digital electrical signal,

The plasma glow starting detection device also comprises an analog-to-digital conversion unit which is electrically connected with the photoelectric conversion element and the control unit;

the analog-to-digital conversion unit is used for receiving the analog electric signal output by the photoelectric conversion element, converting the analog electric signal into a digital electric signal and then sending the digital electric signal to the control unit;

and the control unit is used for receiving the digital electric signal, then comparing the digital electric signal with the critical starting digital electric signal, and judging that plasma in the process chamber is started when the digital electric signal meets the critical starting digital electric signal.

6. A method for detecting plasma ignition, comprising:

S110, detecting an optical signal in a process chamber, and converting the detected optical signal into an electric signal;

And S120, comparing the electric signal with a preset critical starting electric signal, and judging that the plasma in the process chamber is started when the electric signal meets the critical starting electric signal.

7. The method of detecting plasma ignition according to claim 6, further comprising:

And S130, determining the plasma starting intensity according to the electric signal, wherein the magnitude of the electric signal is in positive correlation with the plasma starting intensity.

8. The method of claim 6, wherein the electrical signal comprises a voltage signal or a current signal.

9. A method for detecting a plasma ignition luminance as claimed in any one of claims 6 to 8, wherein said electric signal is an analog electric signal, and said critical ignition electric signal is a critical ignition digital electric signal, and said step S120 includes:

converting the analog electrical signal into a digital electrical signal;

And comparing the digital electric signal with the critical starting digital electric signal, and judging that plasma in the process chamber is started when the digital electric signal meets the critical starting digital electric signal.

10. A process chamber comprising a chamber body and a light transmissive window formed in the chamber body, wherein the plasma ignition detection apparatus of any one of claims 1 to 5 is further provided, and at least a portion of the light transmissive window corresponds to a photosensitive surface of the photoelectric conversion element.

Technical Field

The invention relates to the technical field of semiconductor equipment, in particular to a plasma glow detection device, a plasma glow detection method and a process chamber comprising the plasma glow detection device.

background

Plasma technology is widely used in the field of manufacturing semiconductor devices. In a plasma deposition and etching system, a radio frequency power supply provides energy to a process chamber to generate a plasma; the plasma contains a large amount of active particles such as electrons, ions, excited atoms, molecules, free radicals and the like, and the active particles interact with a wafer which is arranged in the process chamber and exposed to the plasma environment, so that various physical and chemical reactions occur on the surface of the wafer material, the surface performance of the material is changed, and the process processes such as etching, sputtering and the like of the wafer are completed.

Specifically, for example, in the precleaning process chamber, the operating principle is to excite a low-pressure reaction gas (e.g., argon gas, etc.) into plasma by an inductively coupled plasma generating device, and physically bombard the surface of the wafer, so as to remove residues and metal oxides on the surface and at the bottom of the trench, thereby facilitating the subsequent physical vapor deposition (metal film deposition) and improving the adhesion of the deposited film. It is clear that monitoring of plasma ignition conditions in a precleaned process chamber is a critical technique in process development.

disclosure of Invention

the invention aims to solve at least one of the technical problems in the prior art, and provides a plasma glow detection device, a plasma glow detection method and a process chamber comprising the plasma glow detection device.

in order to achieve the above object, a first aspect of the present invention provides a plasma ignition detection apparatus comprising a photoelectric conversion element and a control unit, wherein,

The light sensing surface of the photoelectric conversion element is used for corresponding to the light emitting side of the process chamber so as to detect an optical signal in the process chamber, and the photoelectric conversion element can convert the optical signal into an electrical signal and then send the electrical signal to the control unit;

And the control unit is used for receiving the electric signal, comparing the electric signal with a preset critical starting electric signal, and judging that plasma in the process chamber is started when the electric signal meets the critical starting electric signal.

Optionally, the control unit is further configured to determine the intensity of the plasma ignition according to the electrical signal, where the magnitude of the electrical signal is positively correlated to the intensity of the plasma ignition.

optionally, the photoelectric conversion element comprises a solar cell.

optionally, the method further comprises:

And the light shielding member is used for placing the photoelectric conversion element, and shields other surfaces except the light sensing surface in the photoelectric conversion element.

Optionally, the electrical signal is an analog electrical signal, the critical ignition electrical signal is a critical ignition digital electrical signal,

the plasma glow starting detection device also comprises an analog-to-digital conversion unit which is electrically connected with the photoelectric conversion element and the control unit;

the analog-to-digital conversion unit is used for receiving the analog electric signal output by the photoelectric conversion element, converting the analog electric signal into a digital electric signal and then sending the digital electric signal to the control unit;

and the control unit is used for receiving the digital electric signal, then comparing the digital electric signal with the critical starting digital electric signal, and judging that plasma in the process chamber is started when the digital electric signal meets the critical starting digital electric signal.

In a second aspect of the present invention, a method for detecting plasma ignition is provided, including:

S110, detecting an optical signal in a process chamber, and converting the detected optical signal into an electric signal;

and S120, comparing the electric signal with a preset critical starting electric signal, and judging that the plasma in the process chamber is started when the electric signal meets the critical starting electric signal.

Optionally, the method further comprises:

and S130, determining the plasma starting intensity according to the electric signal, wherein the magnitude of the electric signal is in positive correlation with the plasma starting intensity.

Optionally, the electrical signal comprises a voltage signal or a current signal.

Optionally, when the electrical signal is an analog electrical signal, the critical ignition electrical signal is a critical ignition digital electrical signal, and the step S120 includes:

converting the analog electrical signal into a digital electrical signal;

And comparing the digital electric signal with the critical starting digital electric signal, and judging that plasma in the process chamber is started when the digital electric signal meets the critical starting digital electric signal.

in a third aspect of the present invention, a process chamber is provided, which includes a chamber body, a light-transmitting window disposed on the chamber body, and the plasma glow detection apparatus described above, wherein at least a portion of the light-transmitting window corresponds to a photosensitive surface of the photoelectric conversion element.

According to the plasma glow starting detection method, the plasma glow starting detection device and the process chamber, the optical signal in the process chamber is detected and converted into the electrical signal, and then whether plasma glow is started or not is determined according to the electrical signal. The method for detecting whether the plasma is started is simple and effective, and the cost for detecting the plasma is effectively reduced. In addition, the method is convenient for process developers to prejudge, does not need complex control algorithms and data processing, and can be better popularized and applied.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a process chamber according to an embodiment of the invention;

Fig. 2 is a flowchart of a plasma ignition detection method according to an embodiment of the present invention.

Description of the reference numerals

100: plasma glow detection means;

110: a photoelectric conversion element;

120: a control unit;

130: a light shielding member;

140: an analog-to-digital conversion unit;

200: a process chamber;

210: a chamber body;

220: a light-transmitting window.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

As shown in fig. 1, a first aspect of the present invention relates to a plasma ignition detection apparatus 100, which includes a photoelectric conversion element 110 and a control unit 120 electrically connected to the photoelectric conversion element. The photosensitive surface of the photoelectric conversion element 110 is configured to correspond to the light-emitting side of the process chamber 200 to detect an optical signal in the process chamber 200, and the photoelectric conversion element 110 is further configured to convert the detected optical signal into an electrical signal and send the electrical signal to the control unit 120. The control unit 120 is configured to compare the received electrical signal with a preset critical ignition electrical signal, and determine that plasma in the process chamber 200 is ignited when the electrical signal satisfies the critical ignition electrical signal.

In particular, the plasma within the process chamber 200, when ignited, generates a glow discharge phenomenon that generates a significant amount of glow. Therefore, the optical signal in the process chamber 200 is detected by the photoelectric conversion device 110 and converted into an electrical signal, and then the control unit 120 compares the electrical signal with a predetermined critical ignition signal, and when the electrical signal satisfies the critical ignition signal, it may be determined that plasma in the process chamber 200 is ignited.

It should be noted that, there is no limitation on the specific type of the electrical signal, for example, the electrical signal may be a voltage signal, and of course, the electrical signal may also be a current signal, and the like.

furthermore, it should be understood that no limitation is made to the above-mentioned predetermined critical ignition signal. However, it will be understood by those skilled in the art that the predetermined critical ignition signal should be determined according to theoretical experiments, which should exclude the influence of the ambient light in the process chamber, the influence of the parameters of the photoelectric conversion element itself (e.g., the sensitivity of the photoelectric conversion element to detect the optical signal, etc.), and ensure a minimum threshold value at which the plasma can be ignited after excluding many influences, that is, as long as the electrical signal is greater than or equal to the predetermined critical ignition signal, it can indicate that the plasma in the process chamber is ignited.

In the plasma ignition detection apparatus in this embodiment, first, the optical signal in the process chamber is detected by the photoelectric conversion element and converted into the electrical signal, and then the control unit determines whether the plasma is ignited according to the electrical signal. The device for detecting whether the plasma is started has a simple and effective structure, and can effectively reduce the cost for detecting the plasma. In addition, the method is convenient for process developers to prejudge, does not need complex control algorithms and data processing, and can be better popularized and applied.

optionally, the control unit 120 is further configured to determine the intensity of plasma ignition according to the electrical signal; wherein, the magnitude of the electric signal is in positive correlation with the plasma starting intensity.

The plasma glow detection device in the embodiment can determine the plasma glow generation intensity according to the electric signal, so that a process developer can conveniently pre-judge whether the plasma glow generation intensity meets the process to be performed, and when the plasma glow generation intensity does not meet the process to be performed, the process developer can conveniently adjust in time, a complex control algorithm and data processing are not needed, and the plasma glow detection device can be better popularized and applied.

Alternatively, as a specific structure of the photoelectric conversion element 110 described above, the photoelectric conversion element 110 may be a solar cell. Of course, other structures besides solar cells that can sense light and convert optical signals into electrical signals are also within the scope of the present invention.

Optionally, the apparatus 100 for detecting plasma ignition further comprises a light shielding member 130, wherein the light shielding member 130 is used for placing the photoelectric conversion element 110, and the light shielding member 130 can shield the surface of the photoelectric conversion element 110 except the photosensitive surface. Thus, the light-shielding member 130 prevents the ambient light from being received by the light-sensing surface of the photoelectric conversion element 110, so that the accuracy of detecting the optical signal in the process chamber can be improved, and whether the plasma in the process chamber is ignited or not can be accurately determined.

the light-shielding member 130 is not limited in specific structure, and may be, for example, a frame structure having only one opening corresponding to the light-sensing surface of the photoelectric conversion element 110, and a light-shielding material capable of shielding light is provided on each of the remaining surfaces of the frame structure.

Optionally, the electrical signal is an analog electrical signal, and the critical ignition electrical signal is a critical ignition digital electrical signal. The plasma glow detection device 100 further includes an analog-to-digital conversion unit 140, and the analog-to-digital conversion unit 140 is electrically connected to both the photoelectric conversion element 110 and the control unit 120.

the analog-to-digital conversion unit 140 is configured to receive the analog electrical signal output by the photoelectric conversion element 110, convert the analog electrical signal into a digital electrical signal, and send the digital electrical signal to the control unit 120.

And the control unit 120 is used for comparing the received digital electric signal with the critical ignition digital electric signal, and judging that plasma in the process chamber is ignited when the digital electric signal meets the critical ignition digital electric signal.

As shown in fig. 2, a second aspect of the present invention relates to a method S100 for detecting plasma ignition, including:

and S110, detecting an optical signal in the process chamber, and converting the detected optical signal into an electrical signal.

And S120, comparing the electric signal with a preset critical starting electric signal, and judging that plasma in the process chamber is started when the electric signal meets the critical starting electric signal.

Specifically, when plasma in the process chamber is ignited, a glow discharge phenomenon occurs, and the glow discharge phenomenon generates a large amount of glow. Therefore, the plasma in the process chamber can be judged to be ignited by detecting the optical signal in the process chamber, converting the optical signal into an electrical signal, comparing the electrical signal with a preset critical ignition electrical signal, and when the electrical signal meets the critical ignition electrical signal.

It is to be noted that the structure of the present invention is not limited to the structure for detecting an optical signal in the process chamber and converting the optical signal into an electrical signal. For example, a photoelectric conversion element, specifically, a solar cell may be used, and a photoelectric conversion element having another structure may be selected.

It should be further noted that, there is no limitation on the specific type of the electrical signal, for example, the electrical signal may be a voltage signal, and of course, the electrical signal may also be a current signal, and the like.

Furthermore, it should be understood that no limitation is made to the above-mentioned predetermined critical ignition signal. However, those skilled in the art should know that the preset critical ignition signal should be determined according to theoretical experiments, which should exclude the influence of the ambient light inside the process chamber, the influence of the self-parameters of the photoelectric conversion element (e.g., the sensitivity of the photoelectric conversion element to detect the optical signal, etc.), and ensure a minimum threshold value at which ignition of the plasma can occur after excluding many influences.

In the plasma ignition detection method in this embodiment, an optical signal in the process chamber is detected and converted into an electrical signal, and then whether plasma ignition occurs is determined according to the electrical signal. The method for detecting whether the plasma is started is simple and effective, and the cost for detecting the plasma is effectively reduced. In addition, the method is convenient for process developers to prejudge, does not need complex control algorithms and data processing, and can be better popularized and applied.

optionally, the method S100 for detecting plasma ignition further includes:

S130, determining the plasma starting intensity according to the electric signal; wherein, the magnitude of the electric signal is in positive correlation with the plasma starting intensity.

Specifically, when the plasma is ignited, the stronger the glow discharge phenomenon occurs, the more conspicuous the glow is generated, and thus, the larger the optical signal detected by the photoelectric conversion element is, and the larger the electric signal converted when the optical signal is converted into the electric signal is, so that the intensity of plasma ignition can be calculated inversely according to the magnitude of the electric signal. Therefore, a process developer can judge whether the obtained plasma glow generation intensity meets the conditions of the process to be carried out, and when the obtained plasma glow generation intensity does not meet the conditions, the process developer can improve the plasma glow generation intensity in a mode of increasing radio frequency power and the like.

The plasma glow starting detection method in the embodiment can determine the plasma glow starting intensity according to the electric signal, so that a process developer can conveniently pre-judge whether the plasma glow starting intensity meets the process to be performed, and when the plasma glow starting intensity does not meet the process to be performed, the process developer can conveniently adjust in time, a complex control algorithm and data processing are not needed, and the method can be better popularized and applied.

optionally, the electrical signal is an analog electrical signal, the critical ignition electrical signal is a critical ignition digital electrical signal, and the step S120 specifically includes:

Converting the analog electrical signal into a digital electrical signal;

and comparing the digital electric signal with the critical starting digital electric signal, and judging that plasma in the process chamber is started when the digital electric signal meets the critical starting digital electric signal.

As shown in FIG. 1, a third aspect of the present invention is directed to a process chamber 200 comprising a chamber body 210 and an optically transparent window 220 opening in the chamber body 210. The process chamber 200 further includes the apparatus 100 for detecting plasma ignition described above, and at least a portion of the transparent window 220 corresponds to the photosensitive surface of the photoelectric conversion element 110.

The process chamber in this embodiment has the above-mentioned plasma ignition detection apparatus, and first detects an optical signal in the process chamber by using the photoelectric conversion element and converts the optical signal into an electrical signal, and then the control unit determines whether the plasma is ignited according to the electrical signal. The device for detecting whether the plasma is started has a simple and effective structure, and can effectively reduce the cost for detecting the plasma. In addition, the method is convenient for process developers to prejudge, does not need complex control algorithms and data processing, and can be better popularized and applied.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.