In-situ measurement method and device

Abstract

Various embodiments of the present technology may provide in-situ metrology. A system may include a first sensor embedded within a base and flush with a top surface of the base. The system may also include a lift pin pad having a second sensor arranged to contact the lift pin. The system may also include a third sensor disposed outside the reaction chamber and adjacent the viewing port. The system may also include a processor to receive the output signals from the one or more sensors and use the output signals to determine the film thickness on the wafer.

Description

Technical Field

[0001] The present disclosure generally relates to methods and apparatus for in-situ measurement. More specifically, the present disclosure relates to measuring the amount of deposited material during semiconductor manufacturing. Background Art

[0002] Metrology can be used to analyze and evaluate whether the process is happening as it should during film deposition. An important metric is the thickness of the film deposited on the wafer. This thickness can tell if the correct amount of deposition has occurred. Traditional methods of measuring film thickness are done ex situ (outside of the reaction chamber), these methods are not real-time measurements and are not accurate because the film may change after being removed from the reaction chamber and exposed to different environments. In addition, taking these measurements at different locations can negatively affect yield.

[0003] Films may also accumulate on components of the reaction chamber during processing, which can change the thermal characteristics of the components and may cause uneven heating and thus wafer non-uniformity. Summary of the invention

[0004] Various embodiments of the present technology can provide in-situ metrology. A system can include a first sensor embedded within a susceptor and flush with a top surface of the susceptor. The system can also include a lift pin pad having a second sensor arranged to contact the lift pins. The system can also include a third sensor arranged outside the reaction chamber and adjacent to the viewing port. The system can also include a processor to receive output signals from one or more sensors and use the output signals to determine a film thickness on a wafer.

[0005] According to one aspect, a device includes: a base configured to support a substrate and including a first surface and an opposite second surface, and a plurality of first through holes extending from the first surface to the second surface and a plurality of second through holes extending from the first surface to the second surface; a group of first pins, each first pin being arranged in a through hole among the plurality of first through holes, wherein each first pin is configured to have a plurality of positions; and a group of second pins, each second pin including: a first end adjacent to the first surface of the base and a second end opposite to the first end, wherein: each second pin is arranged in a through hole among the plurality of second through holes; and each second pin has a single fixed position; and a sensor disposed at the first end and electrically connected thereto.

[0006] In one embodiment, the sensor comprises a quartz crystal microbalance and the set of second pins comprises a conductive material.

[0007] In one embodiment, the sensor is flush with the first surface.

[0008] In one embodiment, the base further comprises a plurality of third through holes coupled to a vacuum source.

[0009] In one embodiment, the set of second pins are arranged in a circular pattern.

[0010] In one embodiment, each sensor generates an output signal corresponding to a change in the sensor frequency.

[0011] In one embodiment, the apparatus further comprises a processor configured to receive each output signal and determine a quality value based on the frequency change.

[0012] In one embodiment, the apparatus further comprises a processor configured to receive each output signal and determine a film thickness map on the substrate based on a combination of the output signal and a position of each sensor relative to the other sensors.

[0013] In one embodiment, the apparatus further comprises a mechanism attached to each pin in the set of second pins and configured to exert a force on the sensor.

[0014] On the other hand, an apparatus includes: a base comprising a first surface and an opposing second surface; a plurality of through holes extending from the first surface to the second surface; a plurality of lift pins, each lift pin being disposed in a corresponding through hole among the plurality of through holes; and a plurality of sensors embedded in the base, each sensor comprising a sensing surface disposed flush with the first surface, wherein the sensor is configured to generate an output signal corresponding to a frequency change of the sensing surface.

[0015] In one embodiment, the sensor comprises a quartz crystal microbalance.

[0016] In one embodiment, the base further comprises a plurality of third through holes coupled to a vacuum source.

[0017] In one embodiment, the plurality of sensors are arranged in a circular pattern.

[0018] In one embodiment, each sensor generates an output signal corresponding to a change in the sensor frequency.

[0019] In one embodiment, the apparatus further comprises a processor configured to receive each output signal and determine a quality value based on the frequency change.

[0020] In one embodiment, the apparatus further comprises a processor configured to receive each output signal and determine a film thickness map on the substrate based on a combination of the output signal and a position of each sensor relative to the other sensors.

[0021] In yet another aspect, a system includes: a reaction chamber; a base disposed within the reaction chamber, the base comprising a first surface and an opposing second surface; a plurality of sensors embedded in the base, each sensor comprising a sensing surface disposed flush with the first surface, wherein the sensor is configured to generate an output signal corresponding to a frequency change of the sensing surface; and a processor electrically connected to each sensor, the processor configured to receive each output signal and determine a thickness map based on a combination of the output signal and a position of each sensor relative to the other sensors.

[0022] In one embodiment, the system further includes a mechanism attached to each pin in the set of second pins and configured to exert a force on the sensor.

[0023] In one embodiment, the sensors are arranged in a circular pattern.

[0024] In one embodiment, the processor is further configured to detect when the frequency variation is outside of a predetermined range and to generate an error signal in response.

[0025] In yet another aspect, a system includes: a base disposed within an interior space of a reaction chamber, wherein the base includes a plurality of through holes; a plurality of pins disposed within corresponding through holes among the plurality of through holes; a plurality of pin pads disposed below the base, wherein each pin pad is aligned with one of the plurality of pins; a sensor disposed on a top surface of the pin pad, wherein the sensor generates a signal corresponding to mass; and a processor connected to the sensor and configured to receive the signal, determine a mass change based on the signal, and determine a film thickness based on the determined mass change.

[0026] In yet another aspect, a system includes: a reaction chamber comprising a side wall and a bottom surface perpendicular to the side wall, wherein the side wall and the bottom surface define an interior space of the reaction chamber; a base disposed within the interior space; an observation port disposed within the side wall; an emission meter disposed outside the reaction chamber and adjacent to the observation port, wherein the first emission meter generates an output signal; and a processor connected to the emission meter and configured to receive the output signal and detect a change in the value of the output signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] A more complete understanding of the present technology may be obtained by referring to the detailed description when considered in conjunction with the following illustrative drawings.In the following drawings, like reference numerals refer to like elements and steps throughout the drawings.

[0028] Figure 1 is a block diagram of a system according to various embodiments of the present technology;

[0029] Figure 2 representatively showing a cross-sectional view of a base according to various embodiments of the present technology; and

[0030] Figure 3 A top view of a base according to various embodiments of the present technology is representatively shown. DETAILED DESCRIPTION

[0031] The present technology may be described in terms of functional block components and various processing steps. Such functional blocks may be implemented by any number of components configured to perform a specified function and achieve a variety of results. For example, the present technology may use various reaction chambers, pedestals, lift pins, processors, and showerhead plates.

[0032] refer to Figure 1 , the exemplary system 100 may include a reactor including a showerhead assembly and a reaction chamber 105. The reactor may be used to deposit a film on a substrate such as a wafer 125. The reaction chamber 105 may include a plurality of sidewalls and a bottom surface forming an interior space.

[0033] In an exemplary embodiment, the reaction chamber 105 may further include a first viewing port 145 disposed in the side wall. The first viewing port 145 may extend through the entire thickness of the side wall so that the interior space may be seen from the outside of the reaction chamber 105 through the first viewing port 145. The first viewing port 145 may be formed of quartz, sapphire, or any other suitable transparent material. The first viewing port 145 may be located in an upper region of the side wall and away from the bottom surface.

[0034] In various embodiments, the reaction chamber 105 may further include a second viewing port 170 disposed within the bottom surface of the reaction chamber 105. The second viewing port 170 may extend through the entire thickness of the bottom surface so that the interior space may be seen from the outside of the reaction chamber 105 through the second viewing port 170. The second viewing port 170 may be formed of quartz, sapphire, or any other suitable transparent material. The second viewing port 170 may be located at a position that provides a direct line of sight to the bottom surface of the susceptor 120 and the edge of the susceptor 120.

[0035] In various embodiments, the showerhead assembly may include a cover 110 and a showerhead plate 115. The showerhead plate 115 may include a plurality of through holes 150 configured to allow gas to flow into the inner space of the reaction chamber 105. The showerhead assembly may be arranged above the reaction chamber 105 and close the inner space of the reaction chamber 105. In particular, the showerhead plate 115 may be directly placed on the side wall of the reaction chamber 105.

[0036] In various embodiments, reference Figure 1-3The susceptor 120 may be configured to support the wafer 125 during processing / film deposition and may be disposed within the interior space of the reaction chamber 105. The susceptor 120 may be formed of a ceramic material (e.g., alumina) or a metal material (e.g., metal alloy C22 or any other suitable metal or metal alloy). The susceptor 120 may include a first upwardly facing surface 165 and an opposite second downwardly facing surface. In various embodiments, and during processing, the wafer 125 is located on the first surface 165. In various embodiments, the susceptor 120 may include a heating element (not shown) embedded in the susceptor 120. The heating element may be used to control the temperature of the susceptor 120.

[0037] In various embodiments, the base 120 may include a plurality of first through holes 210 extending from the first surface 165 to the second surface. In an exemplary embodiment, the base 120 includes three through holes 210 arranged in a triangular pattern.

[0038] In some embodiments, the base 120 can be configured to move upward to a processing position (eg, Figure 1 As shown) and move downward to the wafer unloading position. Alternatively, the susceptor 120 can be located in a fixed position.

[0039] In some embodiments, the base 120 may further include a plurality of second through holes.

[0040] In various embodiments, the system 100 may further include a plurality of lift pins 130. Each lift pin 130 may be disposed within a corresponding through hole 210 in the base 120 and extend below the downwardly facing surface of the base 120. The lift pins 130 may be formed of a ceramic material or a metal material.

[0041] In various embodiments, the system 100 may further include a plurality of lift pin pads 135. The lift pin pads 135 may be disposed below the susceptor 120. For example, the lift pin pads 135 may be fixed to the bottom surface of the reaction chamber 105. Alternatively, the lift pin pads 135 may be movable relative to the susceptor 120. For example, the lift pin pads 135 may be coupled to an actuator or the like to move the lift pin pads 135 up and down.

[0042] Each lift pin pad 135 is disposed directly below and aligned with the corresponding lift pin 130. For example, the first lift pin pad 135(a) is disposed directly below the first lift pin 130(a), and the second lift pin pad 135(b) is disposed directly below the second lift pin 130(b). Each lift pin pad 135 may have a top surface having a sufficiently large area to support the corresponding lift pin 130.

[0043] In various embodiments, each lifting pin pad 135 can include a first sensor 140 on a top surface of the pin pad 135. In an exemplary embodiment, the first sensor 140 can include a quarter crystal microbalance configured to generate a first sensor output signal. In an exemplary embodiment, each pin pad 135 in the plurality of pin pads 135 includes a dedicated and independent first sensor 140.

[0044] In various embodiments, the system 100 may further include a thermal sensor 155 configured to measure thermal radiation. The thermal sensor 155 may be disposed outside the reaction chamber 105 and adjacent to the viewing ports 145, 170. For example, a first thermal sensor 155(a) may be adjacent to the first viewing port 145 and a second thermal sensor 155(b) may be adjacent to the second viewing port 170. The first thermal sensor 155(a) may be positioned to measure thermal radiation from components inside the reaction chamber 105, such as the first surface 165 of the susceptor 120, the showerhead plate 115, and opposing sidewalls of the reaction chamber 105. Similarly, the second thermal sensor 155(b) may be positioned to measure thermal radiation from components inside the reaction chamber 105, particularly the bottom surface of the susceptor 120 and the edge of the susceptor 120. The first and second thermal sensors 155(a), 155(b) may be fixedly attached to the exterior of the reaction chamber 120 or rotatably attached. Thermal sensor 155 may include an emissometer or a pyrometer, or any other sensor suitable for measuring thermal radiation or thermal emissivity. Thermal sensor 155 may generate a thermal sensor output signal.

[0045] In some embodiments, the system 100 may further include a set of second sensors 200. Each second sensor 200 may generate a second sensor output signal. The second sensor output signal may indicate a frequency change of the corresponding sensor 200. The set of second sensors 200 may be disposed at the first surface 165 of the base 120. In particular, the set of second sensors 200 may be flush with the first surface 165. The set of second sensors 200 may be arranged across the base 120 in a uniform pattern (e.g., circular and / or equidistant spacing between sensors) or any other suitable pattern. Each second sensor output signal may also correspond to a specific position within the base 120. In an exemplary embodiment, each sensor in the set of second sensors 200 comprises a quartz crystal microbalance.

[0046] In various embodiments, the system 100 may further include a processor 160 configured to receive the sensor signal and generate various control signals based on the received sensor signal. For example, the processor 160 may receive output signals from the first sensor 140, the second sensor 200, and the thermal sensor 155. The processor 160 may be configured to generate a film thickness map on the wafer 125 based on the signal from the first sensor 140 and / or the second sensor 200. For example, the processor 120 may be configured to convert the output signal from the first sensor 140 or the second sensor 200 into a quality value. In some cases, the processor 120 may calculate the quality using a lookup table of predetermined values ​​or using an algorithm.

[0047] In addition, the processor 160 can receive output signals from the thermal sensor 155. The processor 160 can use these output signals to determine changes in emissivity over time. The processor 160 can then use the changes in emissivity to generate an alarm or other message to notify the system 100 (or an operator) that maintenance or cleaning of the reaction chamber 105 and / or the pedestal 120 is required.

[0048] In various embodiments, processor 160 may be configured to transmit control signals to various components of system 100, such as base 120 and heating elements within base 120. For example, processor 160 may control the movement of base 120 and may also control the temperature of base 120 by operating the heating elements.

[0049] The system 100 may further include a set of electrical interconnects 205 configured to provide electrical connections. For example, each electrical interconnect 205 may electrically couple the second sensor 200 to the processor 160 and be configured to transmit the second sensor output signal to the processor 160. Each electrical interconnect 205 may be formed of a conductive material, such as a metal material.

[0050] In some embodiments, the electrical interconnect 205 may include a pin having a rigid form. In this case, each pin may be disposed within a through hole in the plurality of second through holes in the base 120. The first end of the pin may be coupled to one of the set of second sensors 200 to provide an independent electrical connection to the sensor 200.

[0051] In some embodiments, electrical interconnect 205 may include a flexible wire embedded within base 120 .

[0052] Each electrical interconnect 205 can be located at a fixed position within the through hole. Alternatively, each electrical interconnect 205 can be movable within the through hole. For example, where the electrical interconnect is a pin, the second end of the pin 205 can be coupled to a mechanism such as an actuator (not shown) that applies a force to move the pin 205 and the corresponding sensor 200 up and down.

[0053] In various operations, the system 100 can generate a map of the film thickness on the wafer 125. In particular, the processor 160 can move the susceptor 120 to a processing position. During processing, the second sensors 200 can generate an output signal indicating a frequency change of each second sensor 200 and transmit the output signal to the processor 160. The processor 160 can then convert the frequency change into a mass value of each second sensor 200. Since the position of each second sensor 200 is known, the processor 160 can then generate a map of the film thickness on the wafer 125 based on the mass value. The thickness map can indicate whether the film deposited on the wafer 125 is uniform. If the thickness of the film is not uniform, the system 100 can generate an alarm to stop the process or implement a processing plan to correct the non-uniformity, such as adjusting the temperature of a specific area of ​​the susceptor, adjusting the pressure in the reaction chamber 105, etc.

[0054] Additionally or alternatively, the processor 160 may move the susceptor 120 downward to a wafer unloading position. As the susceptor 120 moves downward, the lift pins 130 contact the lift pin pads 135, and the lift pins lift the wafer 125 off the surface of the susceptor 120. In this position, the first sensors 140 may generate an output signal indicating a frequency change of each first sensor 140, and transmit the output signal to the processor 160. The processor 160 may then convert the frequency change into a mass value for each first sensor 140. Since the position of each first sensor 140 is known, the processor 160 may generate a film thickness map on the wafer 125 based on the mass value. The thickness map may indicate whether the film deposited on the wafer 125 is uniform. If the thickness of the film is not uniform, the system 100 may generate an alarm to stop the process or implement a process solution to correct the non-uniformity, such as adjusting the temperature of a particular area of ​​the susceptor, adjusting the pressure in the reaction chamber 105, etc.

[0055] In addition, the system 100 can determine when maintenance and / or cleaning of the reaction chamber 105 and other components, such as the pedestal 120 and the showerhead plate 115, is required. In particular, one or more thermal sensors 155 can generate an output signal indicating the thermal radiation of the surface of the component and transmit the output signal to the processor 160. The processor 160 can then use the thermal radiation data to determine whether maintenance or cleaning is required. As the film is deposited and accumulated on the surface of the component, the thermal radiation of the component will change. For example, as the film accumulates on the pedestal 120 or the showerhead plate 115, the thermal radiation will decrease. This may indicate that the pedestal 120 is not heating the wafer 125 to the desired temperature, which may result in uneven film deposition. Therefore, if the thermal radiation value drops below a predetermined threshold, the processor 160 can generate an alarm or other indication that chamber cleaning or maintenance is required.

[0056] In the foregoing description, the technology has been described with reference to specific exemplary embodiments. The specific embodiments shown and described are illustrations of the technology and its best mode and are not intended to limit the scope of the technology in any way. In fact, for the sake of brevity, the conventional manufacturing, connection, preparation and other functional aspects of the method and system may not be described in detail. In addition, the connecting lines shown in the various figures are intended to represent exemplary functional relationships and / or steps between the various elements. In actual systems, there may be many alternative or additional functional relationships or physical connections.

[0057] The technology has been described with reference to specific exemplary embodiments. However, various modifications and changes may be made without departing from the scope of the technology. The description and drawings are to be regarded as illustrative rather than restrictive, and all such modifications are intended to be included within the scope of the technology. Therefore, the scope of the technology should be determined by the general embodiments described and their legal equivalents, rather than solely by the specific examples described above. For example, the steps described in any method or process embodiment may be performed in any order unless otherwise expressly specified, and are not limited to the explicit order presented in the specific examples. In addition, the components and / or elements described in any device embodiment may be assembled or otherwise operably configured in various arrangements to produce substantially the same results as the technology, and are therefore not limited to the specific configurations described in the specific examples.

[0058] Benefits, other advantages, and solutions to problems have been described above with respect to specific embodiments. However, any benefit, advantage, solution to a problem, or any element that may cause any particular benefit, advantage, or solution to occur or become more significant should not be construed as a critical, required, or essential feature or component.

[0059] The terms "comprises," "comprising," or any variations thereof, are intended to refer to non-exclusive inclusion, such that a process, method, article, composition, or apparatus that includes a list of elements includes not only those elements listed, but may also include other elements not expressly listed or inherent to such process, method, article, composition, or apparatus. Other combinations and / or modifications of the above-described structures, arrangements, applications, proportions, elements, materials, or components used in the practice of the present technology, except those not specifically recited, may be changed or otherwise specially adapted to a particular environment, manufacturing specifications, design parameters, or other operating requirements without departing from the general principles thereof.

[0060] The present technology has been described above with reference to exemplary embodiments. However, changes and modifications may be made to the exemplary embodiments without departing from the scope of the present technology. These and other changes or modifications are intended to be included within the scope of the present technology, as expressed in the following claims.

Claims

1. A device comprising: a susceptor configured to support the substrate and including a first surface and an opposing second surface, and a plurality of first through holes extending from the first surface to the second surface and a plurality of second through holes extending from the first surface to the second surface; a set of first pins, each first pin disposed within a through hole of the plurality of first through holes, wherein each first pin is configured to have a plurality of positions; as well as A set of second pins, each second pin comprising: a first end adjacent to the first surface of the base and a second end opposite the first end, wherein: Each second pin is disposed within a through hole of the plurality of second through holes; and Each second pin has a single fixed position; and A sensor is disposed at the first end and electrically connected thereto.

2. The device according to claim 1, wherein: The sensor comprises a quartz crystal microbalance, and the set of second pins comprises a conductive material.

3. The device according to claim 1, wherein: The sensor is flush with the first surface.

4. The device according to claim 1, wherein: The base also includes a plurality of third through holes coupled to a vacuum source.

5. The device according to claim 1, wherein: The set of second pins are arranged in a circular pattern.

6. The device according to claim 1, wherein: Each sensor generates an output signal corresponding to changes in the sensor frequency.

7. The apparatus of claim 6, further comprising a processor configured to receive each output signal and determine a quality value based on the frequency change.

8. The apparatus of claim 6, further comprising a processor configured to receive each output signal and determine a map of film thickness on the substrate based on a combination of the output signal and a position of each sensor relative to the other sensors.

9. The apparatus of claim 1, further comprising a mechanism attached to each pin in the set of second pins and configured to exert a force on the sensor.

10. An apparatus comprising: Base, including: a first surface and an opposing second surface; a plurality of through holes extending from the first surface to the second surface; a plurality of lift pins, each lift pin disposed within a corresponding through hole of the plurality of through holes; and A plurality of sensors are embedded in the base, and each sensor includes a sensing surface disposed flush with the first surface, wherein the sensor is configured to generate an output signal corresponding to a frequency change of the sensing surface.

11. The device according to claim 10, wherein: The sensor comprises a quartz crystal microbalance.

12. The device according to claim 10, wherein: The base also includes a plurality of third through holes coupled to a vacuum source.

13. The device according to claim 10, wherein: The plurality of sensors are arranged in a circular pattern.

14. The device according to claim 10, wherein: Each sensor generates an output signal corresponding to changes in the sensor frequency.

15. The apparatus of claim 14, further comprising a processor configured to receive each output signal and determine a quality value based on the frequency change.

16. The apparatus of claim 14, further comprising a processor configured to receive each output signal and determine a map of film thickness on the substrate based on a combination of the output signal and a position of each sensor relative to the other sensors.

17. A system comprising: Reaction chamber; a susceptor disposed within the reaction chamber and comprising a first surface and an opposing second surface; a plurality of sensors embedded in the base and each sensor including a sensing surface disposed flush with the first surface, wherein the sensor is configured to generate an output signal corresponding to a frequency change of the sensing surface; as well as A processor is electrically connected to each sensor and is configured to receive each output signal and determine a thickness map based on a combination of the output signal and a position of each sensor relative to the other sensors.

18. The system of claim 17, further comprising a mechanism attached to each pin in the set of second pins and configured to exert a force on the sensor.

19. The system of claim 17, wherein: The sensors are arranged in a circular pattern.

20. The system of claim 17, wherein: The processor is also configured to detect when the frequency variation is outside of a predetermined range and to generate an error signal in response.

21. A system comprising: a base disposed in the interior space of the reaction chamber, wherein the base includes a plurality of through holes; a plurality of pins disposed in corresponding through holes among the plurality of through holes; a plurality of pin pads disposed below the base, wherein each pin pad is aligned with one of the plurality of pins; a sensor disposed on a top surface of the pin pad, wherein the sensor generates a signal corresponding to the mass; and A processor is coupled to the sensor and configured to receive the signal, determine a mass change based on the signal, and determine a film thickness based on the determined mass change.

22. A system comprising: a reaction chamber comprising a side wall and a bottom surface perpendicular to the side wall, wherein the side wall and the bottom surface define an interior space of the reaction chamber; a base disposed within the interior space; a viewing port disposed in the side wall; an emission meter disposed outside the reactor and adjacent to the viewing port, wherein a first emission meter generates an output signal; and A processor is connected to the emission meter and configured to receive the output signal and detect a change in value of the output signal.

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