阅读说明：本技术 承载台污染的改善方法及光刻机 (Method for improving pollution of bearing table and photoetching machine ) 是由 不公告发明人 于 2019-09-27 设计创作，主要内容包括：本发明涉及一种承载台污染的改善方法及光刻机。该改善方法包括：检测单元实时检测分析工艺腔室内晶圆异常数据产生的原因；当异常原因确认为工艺腔室承载台上表面污染时,暂停向所述工艺腔室传送晶圆,并清洁所述承载台上表面,所述清洁完成后继续向所述工艺腔室传送晶圆；其中,当同一工艺腔室中连续大于或等于两片晶圆在同一位置产生异常时,确认所述异常原因为所述承载台上表面污染。通过检测到同一工艺腔室中连续大于或等于两片晶圆在同一位置产生异常时,暂停向所述工艺腔室传送当前批次未作业的晶圆,并清洁所述工艺腔室的承载台上表面,减少了承载台表面沾污影响的晶圆数量,降低了工艺成本。(The invention relates to a method for improving pollution of a bearing table and a photoetching machine. The improvement method comprises the following steps: the detection unit detects and analyzes the reason for generating the wafer abnormal data in the process chamber in real time; when the abnormal reason is determined that the upper surface of the bearing table of the process chamber is polluted, stopping conveying the wafer to the process chamber, cleaning the upper surface of the bearing table, and continuing conveying the wafer to the process chamber after the cleaning is finished; when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table. When the abnormality of more than or equal to two wafers continuously generated at the same position in the same process chamber is detected, the transmission of the wafers which are not operated in the current batch to the process chamber is suspended, and the upper surface of the bearing table of the process chamber is cleaned, so that the number of the wafers affected by the contamination on the surface of the bearing table is reduced, and the process cost is reduced.)

1. A method of ameliorating contamination of a carrier table, comprising:

the detection unit detects and analyzes the reason for generating the wafer abnormal data in the process chamber in real time;

when the abnormal reason is determined that the upper surface of the bearing table of the process chamber is polluted, stopping conveying the wafer to the process chamber, cleaning the upper surface of the bearing table, and continuing conveying the wafer to the process chamber after the cleaning is finished;

when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table.

2. The method of claim 1, wherein the method is adapted for improving stage contamination of a photolithography tool.

3. The method of claim 1, wherein the cleaning is performed by a cleaning mechanism.

4. The method of claim 3, wherein the cleaning mechanism is a grinding stone carried by the photolithography tool.

5. The method of claim 1, wherein the wafer anomaly is a wafer flatness anomaly.

6. The method of claim 1, further comprising, after suspending transfer of wafers to the process chamber: transferring the wafers which are not operated on the bearing table to a temporary storage area;

the cleaning of the upper surface of the bearing table further comprises: and conveying the wafers which are not operated in the temporary storage area to the process chamber for operation.

7. A lithography machine, comprising: a detection module, a control module, a cleaning module, a transmission module,

the detection module is used for detecting and analyzing the reason for the abnormal data of the wafer in the process chamber in real time;

the control module is used for controlling the conveying module to suspend conveying the wafer to the process chamber and controlling the cleaning module to clean the upper surface of the bearing table when the detection module confirms that the abnormal reason is the contamination of the upper surface of the bearing table of the process chamber;

the transfer module is used for continuously transferring the wafer to the process chamber after the cleaning module finishes cleaning;

when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table.

8. The lithography machine of claim 7, wherein said cleaning module performs said cleaning by means of grinding stones carried by the lithography machine itself.

9. The lithography machine of claim 7, wherein the control module is further configured to control the transfer module to transfer the non-processed wafer on the susceptor to a buffer, and the control module is further configured to control the transfer module to transfer the non-processed wafer in the buffer to the process chamber for operation.

10. The lithography machine of claim 9, wherein the lithography machine includes a buffer stage for holding a wafer, and the buffer zone includes the buffer stage.

Technical Field

The invention relates to the technical field of semiconductors, in particular to a method for improving pollution of a bearing table and a photoetching machine.

Background

Wafer backside particles are mainly caused by front-end process defects and particles present on the susceptor. The particles on the back surface of the wafer may cause the surface of the wafer on the stage of the lithography machine to protrude or tilt, which may cause the loss of fidelity of the local pattern due to defocusing during the exposure process, and may also cause the misalignment between the current layer pattern and the previous layer pattern due to the local distortion of the wafer, which finally results in the loss of yield.

Disclosure of Invention

In view of the above, it is necessary to provide a new method for improving contamination of a susceptor.

A method of ameliorating contamination of a carrier table, comprising:

the detection unit detects and analyzes the reason for generating the wafer abnormal data in the process chamber in real time;

when the abnormal reason is determined that the upper surface of the bearing table of the process chamber is polluted, stopping conveying the wafer to the process chamber, cleaning the upper surface of the bearing table, and continuing conveying the wafer to the process chamber after the cleaning is finished;

when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table.

In one embodiment, the method for improving the contamination of the carrier table is suitable for improving the contamination of the carrier table of the lithography machine.

In one embodiment, cleaning the upper surface of the carrier is performed by a cleaning mechanism.

In one embodiment, the cleaning mechanism is a grinding stone carried by the photolithography tool.

In one embodiment, the wafer anomaly is a wafer flatness anomaly.

In one embodiment, after suspending the transfer of the wafer to the process chamber, the method further comprises: and transferring the wafers which are not operated on the bearing table to a temporary storage area. After cleaning the upper surface of the bearing table, the method also comprises the following steps: and conveying the wafers which are not operated in the temporary storage area to the process chamber for operation.

In one embodiment, the method for improving the contamination of the carrier table is suitable for plasma chemical vapor deposition or plasma physical vapor deposition.

According to the method for improving the pollution of the bearing table, the detection unit detects and analyzes the reasons for the abnormal data of the wafer in the process chamber in real time; when the abnormal reason is determined that the upper surface of the bearing table of the process chamber is polluted, stopping conveying the wafer to the process chamber, cleaning the upper surface of the bearing table, and continuing conveying the wafer to the process chamber after the cleaning is finished; when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table. When the abnormality of more than or equal to two wafers continuously generated at the same position in the same process chamber is detected, the transmission of the wafers which are not operated in the current batch to the process chamber is suspended, and the upper surface of the bearing table of the process chamber is cleaned, so that the number of the wafers affected by the contamination on the surface of the bearing table is reduced, and the process cost is reduced.

A lithography machine, comprising: a detection module, a control module, a cleaning module, a transmission module,

the detection module is used for detecting and analyzing the reason for the abnormal data of the wafer in the process chamber in real time;

the control module is used for controlling the conveying module to suspend conveying the wafer to the process chamber and controlling the cleaning module to clean the upper surface of the bearing table when the detection module confirms that the abnormal reason is the stain on the upper surface of the bearing table of the process chamber;

the transfer module is used for continuously transferring the wafer to the process chamber after the cleaning module finishes cleaning;

when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table.

In one embodiment, the cleaning module performs the cleaning by the grinding stone carried by the lithography machine.

In one embodiment, the wafer anomaly is a wafer flatness anomaly.

In one embodiment, the control module is further configured to control the transfer module to transfer the non-processed wafer on the susceptor to the buffer area.

In one embodiment, the control module is further configured to control the transfer module to transfer the wafers that are not in operation in the buffer zone to the process chamber for operation.

In one embodiment, the lithography machine comprises a temporary storage stage for placing the wafer, and the temporary storage area comprises the temporary storage stage.

The photoetching machine comprises a detection module, a control module, a cleaning module and a transmission module; the detection module is used for detecting and analyzing the reason for the abnormal data of the wafer in the process chamber in real time; the control module is used for controlling the transmission module to suspend transmitting the current batch of unoperated wafers to the process chamber and controlling the cleaning module to clean the upper surface of the bearing table of the process chamber when the detection module confirms that the abnormal reason is the contamination of the upper surface of the bearing table of the process chamber; the transfer module is used for continuously transferring the unoperated wafer to the process chamber after the cleaning module finishes cleaning; when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table. When the photoetching machine detects that two wafers which are continuously larger than or equal to each other in the same process chamber are abnormal at the same position, the photoetching machine suspends the transmission of the wafers which are not operated in the current batch to the process chamber, and cleans the upper surface of a bearing table of the process chamber, so that the quantity of the wafers which are affected by the contamination on the surface of the bearing table is reduced, and the process cost is reduced.

Drawings

FIG. 1 is a flow chart of a method for improving contamination of a susceptor in an embodiment;

FIG. 2 is a block diagram of a lithography machine in one embodiment.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It will be understood that when an element or layer is referred to as being "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it can be directly on, adjacent to, connected or coupled to the other elements or layers or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly adjacent to," "directly connected to" or "directly coupled to" other elements or layers, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.

Spatial relational terms such as "under," "below," "under," "above," "over," and the like may be used herein for convenience in describing the relationship of one element or feature to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, then elements or features described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary terms "under" and "under" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatial descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

After the wafer is photoetched on a bearing table with particles on the surface, photoetching hot spots, namely photoetching defects generated on the wafer, exist on the surface of the obtained wafer, and the photoetching hot spots caused by the particles on the back of the wafer are a main exception of photoetching patterns. In the traditional photoetching process, when surface hot spot abnormality is detected at the same position on the surfaces of five wafers continuously operated on the same bearing table, the hot spot abnormality is determined to be caused by surface contamination of the bearing table, after the operation of the current batch of products is completed, the photoetching machine automatically runs a surface cleaning step, a grinding stone carried by the photoetching machine grinds the upper surface of the wafer bearing table, and after the contamination on the surface of the bearing table is removed, the operation of the next batch of products is carried out. Before the photoetching machine automatically removes the surface contamination of the bearing table, more than or equal to five wafers are affected by the surface contamination of the bearing table, so that surface hot spot abnormality occurs.

In one embodiment, as shown in fig. 1, a method for improving contamination of a susceptor includes:

s102, detecting and analyzing wafer abnormity.

Before an exposure process is started, a detection unit detects and analyzes the reason for generating abnormal data of a wafer in a process chamber in real time; if the two wafers are continuously greater than or equal to the abnormality in the same position in the same process chamber, determining that the abnormality is the pollution on the upper surface of the bearing table of the process chamber, and executing the step S104; if the abnormality of two wafers continuously or more in the same process chamber at the same position is not detected, normal process steps are carried out.

In one embodiment, the wafer anomaly is a wafer flatness anomaly, and the flatness of the wafer surface can reflect whether particles exist on the wafer back surface.

S104, suspending the operation of the process chamber.

And when the detection unit confirms that the abnormality reason is the pollution of the upper surface of the bearing table of the process chamber, suspending the transmission of the wafers which are not operated in the current batch to the process chamber.

And S106, cleaning the bearing table.

And after the transmission of the current batch of unoperated wafers to the process chamber is suspended, cleaning the upper surface of the bearing table of the process chamber to remove particles on the upper surface of the bearing table.

In one embodiment, cleaning the upper surface of the susceptor of the process chamber is performed by a cleaning mechanism.

In one embodiment, the cleaning mechanism for cleaning the upper surface of the susceptor in the process chamber is a grinding stone carried by the photolithography tool.

S108, continuing to use the process chamber operation.

After the cleaning of the susceptor is completed, the unprocessed wafer is continuously transferred to the process chamber, and the detection of step S102 is repeated.

In one embodiment, the method for improving the contamination of the bearing table is suitable for improving the contamination of the bearing table of the photoetching machine table.

In one embodiment, the method for improving the contamination of the bearing table is suitable for plasma chemical vapor deposition or plasma physical vapor deposition. The anomaly is a surface filming anomaly caused by backside particles.

In one embodiment, step S104 is followed by transferring the unprocessed wafers on the susceptor to a buffer area. In one embodiment, the temporary storage area is a transfer chamber, and in other embodiments, the temporary storage area can be optionally set according to actual conditions, for example, the temporary storage area is set in a process area.

In one embodiment, step S106 is followed by transferring the wafers not in operation in the buffer zone to the process chamber for operation.

According to the method for improving the pollution of the bearing table, the detection unit detects and analyzes the reasons for the abnormal data of the wafer in the process chamber in real time; when the abnormal reason is determined that the upper surface of the bearing table of the process chamber is polluted, stopping conveying the wafer to the process chamber, cleaning the upper surface of the bearing table, and continuing conveying the wafer to the process chamber after the cleaning is finished; when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table. When the abnormality of more than or equal to two wafers continuously generated at the same position in the same process chamber is detected, the transmission of the wafers which are not operated in the current batch to the process chamber is suspended, and the upper surface of the bearing table of the process chamber is cleaned, so that the number of the wafers affected by the contamination on the surface of the bearing table is reduced, and the process cost is reduced.

As shown in FIG. 2, in one embodiment, there is provided a lithography machine 100 comprising: a detection module 102, a control module 104, a cleaning module 106, and a transfer module 108.

The detection module 102 is configured to detect and analyze a cause of wafer abnormal data in a process chamber in real time, where when two or more wafers in the same process chamber are continuously abnormal at the same position, it is determined that the cause of the abnormality is contamination of an upper surface of a susceptor of the process chamber.

The control module 104 is configured to control the transfer module 108 to suspend transferring the current batch of unprocessed wafers to the process chamber and control the cleaning module 106 to clean the upper surface of the susceptor of the process chamber when the detection module 102 detects that the cause of the abnormality is contamination of the upper surface of the susceptor of the process chamber.

A transfer module 108 that continues to transfer the unprocessed wafer to the process chamber after the cleaning module completes the cleaning.

In one embodiment, the cleaning module performs the cleaning by the grinding stone carried by the lithography machine.

In one embodiment, the wafer anomaly is a wafer flatness anomaly, and the flatness of the wafer surface can reflect whether particles exist on the wafer back surface.

In one embodiment, the control module is further configured to control the transfer module to transfer the non-processed wafer on the susceptor to the buffer area. In one embodiment, the temporary storage area is a transfer chamber, and in other embodiments, the temporary storage area can be optionally set according to actual conditions, for example, the temporary storage area is set in a process area.

In one embodiment, the control module is further configured to control the transfer module to transfer the wafers that are not in operation in the buffer zone to the process chamber for operation.

In one embodiment, the lithography machine comprises a temporary storage stage for placing the wafer, and the temporary storage area comprises the temporary storage stage. Wafers which are not operated and are transmitted out of the process chambers are placed through the temporary storage carrying table, and the influence of abnormal particles on the carrying table of one process chamber on the normal operation of other process chambers is avoided.

The photoetching machine comprises a detection module, a control module, a cleaning module and a transmission module; the detection module is used for detecting and analyzing the reason for the abnormal data of the wafer in the process chamber in real time; the control module is used for controlling the transmission module to suspend transmitting the current batch of unoperated wafers to the process chamber and controlling the cleaning module to clean the upper surface of the bearing table of the process chamber when the detection module confirms that the abnormal reason is the contamination of the upper surface of the bearing table of the process chamber; the transfer module is used for continuously transferring the unoperated wafer to the process chamber after the cleaning module finishes cleaning; when two or more wafers are continuously abnormal at the same position in the same process chamber, the abnormality is determined to be the pollution on the upper surface of the bearing table. When the photoetching machine detects that two wafers which are continuously larger than or equal to each other in the same process chamber are abnormal at the same position, the photoetching machine suspends the transmission of the wafers which are not operated in the current batch to the process chamber, and cleans the upper surface of a bearing table of the process chamber, so that the quantity of the wafers which are affected by the contamination on the surface of the bearing table is reduced, and the process cost is reduced.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.