Radio frequency loop tuning system, tuning method and process tool for semiconductor devices

Abstract

The application discloses a radio frequency loop adjusting system, an adjusting method and a process machine table of a semiconductor device. The adjusting system comprises a first radio frequency transmitter and a second radio frequency transmitter, which respectively provide a first radio frequency current value into a first reaction cavity and a second radio frequency current value into a second reaction cavity; a current detection device acquires the first radio frequency current value and the second radio frequency current value; a controller is configured to: obtain a radio frequency current ratio of the two based on the first radio frequency current value and the second radio frequency current value; substitute the radio frequency current ratio into a first fitting formula and a second fitting formula to obtain a phase synchronization compensation value of the second radio frequency current; provide a target radio frequency current; and adjust the first radio frequency current value and the second radio frequency current value based on the target radio frequency current and the phase synchronization compensation value, so that the film deposition rates in the two reaction cavities are consistent. The application can reduce the crosstalk between the machine table cavities, keep the film formation rates in the cavities consistent and reduce the process error.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, specifically to a radio frequency (RF) circuit adjustment system, a semiconductor device process equipment, an RF circuit adjustment method, and a computer-readable storage medium. Background Technology

[0002] In existing dual-chamber semiconductor device fabrication equipment, such as plasma-enhanced chemical vapor deposition (PECVD) systems, each reaction chamber is equipped with an independent power supply, requiring the use of multiple power supplies. When multiple power supplies are used in a PECVD system without phase synchronization, the output waveforms of each power supply may be in different phases. This causes them to generate peak currents and voltages at different times, resulting in mutually interfering electromagnetic fields. This interference affects plasma stability, leading to uneven film deposition within the reaction chamber. Phase synchronization, by unifying the phases of each power supply, ensures that each power supply generates voltage and current peaks at the same time, thereby reducing the possibility of mutual interference.

[0003] Therefore, to resolve crosstalk between the two chambers in the process equipment, the two power supplies can be synchronized in phase. The current method for power supply phase synchronization involves adjusting the phase of the two initial RF power signals to zero during the initial stage of applying their respective RF power signals to the two reaction chambers. However, due to inherent errors in the hardware within the two reaction chambers—for example, hardware errors may include, but are not limited to, the thickness of the aluminum fluoride in the aluminum heating plate, the depth of the RF grounding mesh in the ceramic heating plate, the precision of the spray plate surface treatment, the mechanical tolerances of the side ceramic components, uneven gas distribution in the split-gas pipeline, and human installation tolerances—process deviations can occur in the deposited thin film.

[0004] Furthermore, over time, a phase difference will still develop between the waveforms of the RF power signals from the two power supplies, resulting in crosstalk between the reaction chambers. Further, RF instability within the two reaction chambers can lead to unstable process performance and even affect hardware matching, causing mismatch and ultimately RF total reflection, resulting in machine downtime. Moreover, since adjusting process parameters (recipe settings) is not permitted in dual-cavity processes, small errors are always likely to exist.

[0005] In order to solve the above-mentioned problems in the prior art, there is an urgent need in the field for a radio frequency circuit adjustment technology that can automatically and in real time adjust the phase uniformity of the radio frequency power signal in each reaction chamber without adjusting the parameter settings in the process, thereby reducing crosstalk between chambers. It can also adjust the film deposition rate in real time, thereby making the film deposition rate of each chamber consistent and reducing process errors. Summary of the Invention

[0006] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify key or decisive elements of all aspects, nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed descriptions that follow.

[0007] To overcome the aforementioned deficiencies in the prior art, the present invention provides an RF circuit adjustment system, a semiconductor device process equipment, an RF circuit adjustment method, and a computer-readable storage medium. This system can automatically and in real-time adjust the phase uniformity of the RF power signals in each reaction chamber without adjusting the parameter settings during the process, thereby reducing crosstalk between chambers. It can also adjust the film deposition rate in real-time, ensuring consistent film deposition rates between chambers and reducing process errors.

[0008] Specifically, the radio frequency (RF) loop adjustment system provided according to a first aspect of the present invention includes: a first RF transmitter and a second RF transmitter, respectively configured to provide a first RF current value to a first reaction cavity and a second RF current value to a second reaction cavity; a current detection device, configured to acquire the first RF current value and the second RF current value; and a controller configured to: obtain an RF current ratio of the first RF current and the second RF current based on the first RF current value and the second RF current value; substitute the RF current ratio into a first fitting formula and a second fitting formula to obtain a phase synchronization compensation value for the second RF current, wherein the first fitting formula includes a relationship between the phase angle of the first RF current and the current, and the second fitting formula includes a relationship between the phase angle of the second RF current and the current; provide a target RF current via the first RF generator; and adjust the first RF current value and the second RF current value based on the target RF current and the phase synchronization compensation value to make the thin film deposition rate in the first reaction cavity and the second reaction cavity consistent.

[0009] Furthermore, in some embodiments of the present invention, a signal splitter coupled to the first radio frequency transmitter and the second radio frequency transmitter is further included, and the controller is further configured to generate, during machine testing, a first radio frequency power signal supplied to the first reaction cavity and a second radio frequency power signal supplied to the second reaction cavity via the signal splitter.

[0010] Furthermore, in some embodiments of the present invention, the step of generating a first radio frequency power signal supplied to the first reaction cavity and a second radio frequency power signal supplied to the second reaction cavity via the signal splitter during the machine testing process includes: the first radio frequency transmitter outputting a sine wave signal as a reference signal for phase synchronization of the two reaction cavities; and via the signal splitter, splitting the sine wave signal into two synchronization signals and outputting them back to the first radio frequency transmitter as the first radio frequency power signal, and outputting them to the second radio frequency transmitter as the second radio frequency power signal.

[0011] Furthermore, in some embodiments of the present invention, the step of obtaining the radio frequency current ratio of the first radio frequency current and the second radio frequency current based on the first radio frequency current value and the second radio frequency current value includes: obtaining the first radio frequency current value of the first radio frequency power signal and the second radio frequency current value of the second radio frequency power signal through the current detection device; and obtaining the radio frequency current ratio of the first radio frequency current and the second radio frequency current, wherein the formula for the radio frequency current ratio is as follows:

[0012] I2=α-βI1

[0013] Where I1 represents the first RF current value, I2 represents the second RF current value, β represents the proportional coefficient, and α represents the offset compensation.

[0014] Furthermore, in some embodiments of the present invention, the first radio frequency transmitter and the second radio frequency transmitter are respectively connected to heating plates in their respective reaction chambers. By adjusting the first radio frequency current on the first heating plate and the second radio frequency current on the second heating plate, the thin film deposition rate on the first heating plate and the thin film deposition rate on the second heating plate are adjusted.

[0015] Furthermore, in some embodiments of the present invention, the length of the RF line from the signal splitter to the CEX feed point of the first RF transmitter is the same as the length of the RF line from the signal splitter to the CEX feed point of the second RF transmitter.

[0016] Furthermore, in some embodiments of the present invention, the step of substituting the radio frequency current ratio into the first fitting formula and the second fitting formula to obtain the phase synchronization compensation value of the second radio frequency current includes: acquiring test data of the instrument, wherein the test data includes the first radio frequency current value and the second radio frequency current value during the test; and based on the first radio frequency current value and the second radio frequency current value, obtaining the first fitting formula and the second fitting formula, wherein the formula of the first fitting formula is as follows:

[0017] offset1 = AI1 + B

[0018] Where offset1 represents the phase compensation value of the first RF current, I1 represents the first RF current value, A is the proportional coefficient, B is the offset compensation, and the formula for the second fitting formula is as follows:

[0019] offset2 = CI2 + D

[0020] Where offset2 represents the phase compensation value of the second RF current, I2 represents the second RF current value, C is the proportional coefficient, and D is the offset compensation; and the phase synchronization compensation value is obtained by substituting the RF current proportionality into the first fitting formula and the second fitting formula.

[0021] Furthermore, in some embodiments of the present invention, the test data further includes a first film thickness test value in the first reaction cavity and a second film thickness test value in the second reaction cavity. After the step of obtaining the first fitting formula and the second fitting formula, the method further includes: based on the first fitting formula and the second fitting formula, performing a second fitting based on the first film thickness test value and the second film thickness test value to obtain a third fitting formula and a fourth fitting formula, wherein the third fitting formula includes the phase angle, film thickness and current relationship of the first radio frequency current, and the fourth fitting formula includes the phase angle, film thickness and current relationship of the second radio frequency current.

[0022] Furthermore, in some embodiments of the present invention, the step of adjusting the first radio frequency current value and the second radio frequency current value based on the target radio frequency current and the phase synchronization compensation value to make the thin film deposition rate in the first reaction cavity and the second reaction cavity consistent includes: assigning the phase synchronization compensation value between the second radio frequency current and the target radio frequency current to the second radio frequency transmitter; synchronously adjusting the first radio frequency current value and the second radio frequency current value to make the first radio frequency current value and the second radio frequency current value tend to be consistent; and in response to the first radio frequency current value and the second radio frequency current value reaching consistency, the thin film deposition rate in the first reaction cavity and the second reaction cavity becomes consistent.

[0023] Furthermore, the semiconductor device process apparatus provided according to the second aspect of the present invention includes: two reaction chambers, each of which performs a thin film deposition process, wherein the upper electrodes in the two reaction chambers are located within the same shielding cover; an isolation cover plate disposed between the two reaction chambers for isolating radio frequency signal interference between the two reaction chambers; and the radio frequency circuit adjustment system provided in the first aspect of the present invention for adjusting the first radio frequency current value in the first reaction chamber and the radio frequency current value in the second reaction chamber to make the thin film deposition rates in the first reaction chamber and the second reaction chamber consistent.

[0024] Furthermore, the radio frequency (RF) loop adjustment method provided by the third aspect of the present invention includes the following steps: providing a first RF current value to a first reaction cavity and a second RF current value to a second reaction cavity via a first RF transmitter and a second RF transmitter in the RF loop adjustment system of the semiconductor device process equipment provided by the second aspect of the present invention; obtaining an RF current ratio of the first RF current and the second RF current based on the first RF current value and the second RF current value; substituting the RF current ratio into a first fitting formula and a second fitting formula to obtain a phase synchronization compensation value for the second RF current, wherein the first fitting formula includes the relationship between the phase angle of the first RF current and the current, and the second fitting formula includes the relationship between the phase angle of the second RF current and the current; providing a target RF current via the first RF generator; and adjusting the first RF current value and the second RF current value based on the phase synchronization compensation value to make the thin film deposition rate in the first reaction cavity and the second reaction cavity consistent.

[0025] Furthermore, according to a fourth aspect of the present invention, a computer-readable storage medium is provided having computer instructions stored thereon. When the computer instructions are executed by a processor, the radio frequency circuit adjustment method described above, provided in the third aspect of the present invention, is implemented. Attached Figure Description

[0026] The above-described features and advantages of the present invention will be better understood after reading the following detailed description of embodiments of the present disclosure in conjunction with the accompanying drawings. In the drawings, components are not necessarily drawn to scale, and components having similar related properties or features may have the same or similar reference numerals.

[0027] Figure 1 A schematic diagram of the structure of a process equipment for a semiconductor device according to some embodiments of the present invention is shown;

[0028] Figure 2 A schematic diagram of the structure of a radio frequency loop adjustment system in a process machine according to some embodiments of the present invention is shown;

[0029] Figure 3 A flowchart of a radio frequency circuit adjustment method provided according to some embodiments of the present invention is shown;

[0030] Figure 4 A flowchart of a radio frequency circuit adjustment method according to a specific embodiment of the present invention is shown;

[0031] Figure 5A The diagram illustrates the phase angle and current curves of a first radio frequency power supply and a second radio frequency power supply provided according to some embodiments of the present invention; and

[0032] Figure 5B A schematic diagram of the phase angle and film thickness of a first radio frequency power supply and a second radio frequency power supply provided according to some embodiments of the present invention is shown.

[0033] Figure label:

[0034] 100. Process equipment for semiconductor devices;

[0035] 110 First reaction chamber;

[0036] 120 Second reaction chamber;

[0037] 130 shielding cover;

[0038] 140 Isolation cover plate;

[0039] 150 spray plates;

[0040] 161 First RF power supply matching unit;

[0041] 162 Second RF power supply matching unit;

[0042] 170 heating plate;

[0043] 200 RF loop conditioning system;

[0044] 210 First radio frequency generator;

[0045] 220 Second radio frequency generator;

[0046] 211, 221 CEX feed points;

[0047] 212, 222 CEX output points;

[0048] 230 Current detection device;

[0049] 240 signal splitter;

[0050] 241, 242 RF cables;

[0051] Steps S310 to S350;

[0052] Steps S410 to S460; and

[0053] Curves 510, 520, 530, and 540. Detailed Implementation

[0054] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention is presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to these embodiments. On the contrary, the purpose of describing the invention in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of the present invention. To provide a thorough understanding of the invention, many specific details will be included in the following description. The invention may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of the invention, some specific details will be omitted in the description.

[0055] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0056] Furthermore, the terms "upper," "lower," "left," "right," "top," "bottom," "horizontal," and "vertical" used in the following description should be understood as the orientations shown in the relevant paragraphs and accompanying drawings. These relative terms are for illustrative purposes only and do not imply that the described apparatus must be manufactured or operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0057] It is understood that although terms such as "first," "second," and "third" may be used herein to describe various components, regions, layers, and / or parts, these components, regions, layers, and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers, and / or parts. Therefore, the first components, regions, layers, and / or parts discussed below may be referred to as second components, regions, layers, and / or parts without departing from some embodiments of the present invention.

[0058] As mentioned above, to resolve crosstalk between the two chambers in a process equipment, the two power supplies can be synchronized in phase. Currently, the method for power supply phase synchronization involves adjusting the phase of the two initial RF power signals applied to the two reaction chambers to achieve a zero phase difference. However, due to inherent hardware errors within the two reaction chambers, and the fact that phase differences will still develop between the RF power signal waveforms over time, crosstalk between the reaction chambers will persist. Furthermore, RF instability within the two reaction chambers can lead to unstable process performance, even affecting hardware matching and causing mismatch, resulting in total radio frequency reflection and equipment shutdown.

[0059] To address the aforementioned problems in the prior art, this invention provides an RF circuit adjustment system, a semiconductor device process equipment, an RF circuit adjustment method, and a computer-readable storage medium. This system can automatically and in real-time adjust the phase uniformity of the RF power signals in each reaction chamber without adjusting the parameter settings during the process, thereby reducing crosstalk between chambers. It can also adjust the film deposition rate in real-time, ensuring consistent film deposition rates between chambers and reducing process errors.

[0060] In some non-limiting embodiments, the radio frequency circuit adjustment system provided in the first aspect of the present invention can be configured in the process equipment of the semiconductor device provided in the second aspect of the present invention, and used to implement the radio frequency circuit adjustment method provided in the third aspect of the present invention.

[0061] Specifically, in some non-limiting embodiments, the computer-readable storage medium provided in the fourth aspect of the present invention stores computer instructions thereon. When the computer instructions are executed by a processor, they can be used to implement the radio frequency circuit adjustment method provided in the third aspect of the present invention.

[0062] The working principle of the above-described RF circuit adjustment system will be described below with reference to some embodiments of semiconductor device process equipment and RF circuit adjustment methods. Those skilled in the art will understand that these embodiments of semiconductor device process equipment and RF circuit adjustment methods are merely non-limiting implementations provided by the present invention, intended to clearly demonstrate the main concepts of the invention and provide specific solutions convenient for public implementation, rather than limiting all operating methods or functions of the RF circuit adjustment system. Similarly, this RF circuit adjustment system is also only one non-limiting implementation provided by the present invention, and does not limit other configurations in the semiconductor device process equipment or the implementing entities of each step in the RF circuit adjustment method.

[0063] Please refer to Figure 1, Figure 1 A schematic diagram of the structure of a process equipment for a semiconductor device provided according to some embodiments of the present invention is shown.

[0064] like Figure 1 As shown, in some embodiments of the present invention, the semiconductor device process equipment 100 may include two reaction chambers, a first reaction chamber 110 and a second reaction chamber 120. Each reaction chamber may include a heating plate 170 for supporting a substrate for thin film deposition. A spray plate 150 may be provided above each reaction chamber, through which process gases may be sprayed onto the substrate on the heating plate 170 below to deposit a thin film on the substrate surface. A first RF power matching device 161 and a second RF power matching device 162 may also be connected above the first reaction chamber 110 and the second reaction chamber 120 to match the impedance between the RF power supply and the load, ensuring that the RF power supply can effectively transfer energy to the load.

[0065] In some optional embodiments, the semiconductor device process equipment 100 can be a PECVD process equipment. The radio frequency (RF) power supply can be located outside the reaction chamber, and its output energy can be connected via an RF copper strip to a matching RF input port of a single reaction chamber. The matching RF output port can be connected via a copper strip to the spray plate 150. That is, in this embodiment, the two reaction chambers can be respectively connected to an external first RF generator and a second RF generator, serving as the RF power supply for the two reaction chambers to provide RF signals to the corresponding reaction chambers.

[0066] Furthermore, each reaction chamber may include an upper electrode and a lower electrode connected to an external radio frequency generator. Under the action of the electric field excited by the radio frequency source, the process gas can be ionized to form plasma, causing the gaseous material containing the thin film composition to undergo a chemical reaction, thereby realizing the growth of thin film material on the substrate. Optionally, the upper electrode can be located in the spray plate 150, while the lower electrode can be located in the heating plate 170.

[0067] Furthermore, such as Figure 1As shown, since the upper electrodes in the first reaction chamber 110 and the second reaction chamber 120, as well as the copper strip of the spray plate connected to the spray plate 150, are all within the same shielding cover 130, there is spatial radiation between the two reaction chambers, resulting in mutual interference. Therefore, to solve this problem, an isolation cover 140 can be provided between the first reaction chamber 110 and the second reaction chamber 120 to isolate the radio frequency signal interference between the two reaction chambers. Moreover, even if there are some gaps in the isolation cover 140 during the actual installation process due to engineering factors, it can still achieve more than 90% effective shielding. However, despite this, the isolation effect within the two reaction chambers is still not ideal. In this embodiment, if crosstalk occurs between the two chambers, the radio frequency instability within each reaction chamber will cause unstable process performance, and may even affect the matching work between hardware, leading to mismatch and radio frequency total reflection causing machine downtime.

[0068] To address this, the semiconductor device process equipment 100 may also include a radio frequency (RF) circuit adjustment system. This RF circuit adjustment system can automatically and in real-time adjust the first RF current value in the first reaction chamber 110 and the second RF current value in the second reaction chamber 120 during the thin film deposition process in both reaction chambers. This automatically and in real-time adjusts the film deposition rate in both chambers, ensuring consistent film deposition rates, reducing deposition errors in different reaction chambers, improving the uniformity of film deposition across multiple chambers, and ultimately enhancing the overall film deposition quality of the semiconductor device process equipment.

[0069] Specifically, please see Figure 2 , Figure 2 A schematic diagram of the structure of a radio frequency circuit adjustment system provided according to some embodiments of the present invention in a process equipment is shown.

[0070] like Figure 2 As shown, in some embodiments of the present invention, the radio frequency loop adjustment system 200 may include a first radio frequency generator 210 (RFG), a second radio frequency generator 220, a current detection device 230, and a controller (not shown in the figures). The first radio frequency generator 210 and the second radio frequency generator 220 may be used to provide a first radio frequency current value to the first reaction cavity 110 and a second radio frequency current value to the second reaction cavity 120, respectively. The current detection device 2130 may be used to acquire the first radio frequency current value and the second radio frequency current value.

[0071] Optionally, the first radio frequency generator 210 can be connected to the first heating plate in the first reaction chamber 110, and the second radio frequency generator 220 can be connected to the second heating plate in the second reaction chamber 120. By adjusting the first radio frequency current on the first heating plate and the second radio frequency current on the second heating plate, the thin film deposition rate on the first heating plate and the thin film deposition rate on the second heating plate can be adjusted respectively. Correspondingly, in this embodiment, the current detection device 230 can detect the current value on the heating plate.

[0072] The controller can be configured to perform the steps of the RF loop adjustment method provided in another aspect of the present invention. Specifically, please refer to... Figure 3 , Figure 3 A flowchart of a radio frequency circuit adjustment method according to some embodiments of the present invention is shown. Further, it can be combined with... Figure 4 Common understanding Figure 4 A flowchart of a radio frequency circuit adjustment method provided according to a specific embodiment of the present invention is shown.

[0073] First, such as Figure 3 As shown, in some embodiments of the present invention, the radio frequency (RF) loop adjustment method may include the following steps. First, step S310 may be performed: a first RF current value is provided to the first reaction cavity and a second RF current value is provided to the second reaction cavity via a first RF transmitter and a second RF transmitter in the RF loop adjustment system of the semiconductor device process equipment.

[0074] Specifically, it can be combined with Figure 2 It is understood that in some embodiments, the RF loop adjustment system 200 may further include a signal splitter 240. For example, the signal splitter 240 may be a split-to-two control board to split the original signal into two. The signal splitter 240 may be coupled to a first RF generator 210 and a second RF generator 220. The controller may also be configured to generate, during machine testing, a first RF power signal supplied to the first reaction chamber 110 and a second RF power signal supplied to the second reaction chamber 120 via the signal splitter 240.

[0075] Step S310 may further include the following process: the controller can control the CEX output point 212 (cex out) of the first RF generator 210 to always output a sine wave signal as a reference signal for phase synchronization of the two reaction cavities. This sine wave signal is split into two by the signal splitter 240, resulting in two synchronization signals. One is output back to the first RF generator 210 as the first RF power signal, and the other is output to the second RF generator 220 as the second RF power signal. That is, after passing through the signal splitter 240, the sine wave signal can be used as synchronization signals for the two RF power supplies and input to the CEX feed point 211 (cex in) of the first RF generator 210 and the CEX feed point 221 (cex in) of the second reaction cavity 120.

[0076] Furthermore, in some preferred embodiments, the length of the RF line 241 from the signal splitter 240 to the CEX feed point 211 of the first RF generator 210 can preferably be the same as the length of the RF line 242 from the CEX feed point 221 of the second RF generator 220. Since the two sinusoidal signals output from the output port of the 1-to-2 signal splitter 240 have the same phase, to ensure that the signals received by the two RF generators also have the same phase, the transmission distance between the signal splitter 240 and the CEX feed points 211 and 221 of the RF generators can be set to be the same, so that the lengths of the RF lines 241 and 242 are set to be consistent, ensuring that the two RF power signals travel on the same path length, thus ensuring that the two signals have the same phase and reducing the generation of RF crosstalk between chambers. If the two RF power signals travel on different path lengths, it is easy for the two signals to have inconsistent phases.

[0077] Optionally, the RF lines 231 and 232 are preferably made of the same material to ensure that the two RF power signals transmit at the same speed, thereby improving the phase synchronization of the two signals and reducing the generation of RF crosstalk between the chambers.

[0078] After that, continue as Figure 3 As shown, step S320 can be executed: based on the first radio frequency current value and the second radio frequency current value, obtain the radio frequency current ratio of the first radio frequency current and the second radio frequency current.

[0079] Specifically, combined Figure 2 and Figure 4As shown, in some embodiments, step S410 can be performed: detecting the radio frequency current value of the heating plates in the first reaction chamber 110 and the second reaction chamber 120. The current detection device 230 can detect the first radio frequency current value of the first radio frequency power signal on the first heating plate and the second radio frequency current value of the second radio frequency power signal on the second heating plate, respectively. Then, step S420 can be performed to obtain the radio frequency current ratio of the first radio frequency current and the second radio frequency current, wherein the formula for the radio frequency current ratio can be as follows:

[0080] I2=α-βI1

[0081] Where I1 represents the first RF current value, I2 represents the second RF current value, β represents the proportionality coefficient, and α represents the offset compensation. For example, in some optional embodiments, to ensure that the generated film thickness in the two reaction chambers is consistent, the RF current ratio in the two reaction chambers can be set to I2 = 3.125 - 1.125I1. Since the ratio may vary for different process equipment, it is necessary to test the RF current ratio required by the current equipment during the installation phase. Optionally, this ratio can also be periodically retested and calibrated according to the actual application of the equipment.

[0082] Then, please continue as follows Figure 3 As shown, step S330 can be executed: substituting the RF current ratio into the first fitting formula and the second fitting formula to obtain the phase synchronization compensation value of the second RF current.

[0083] Specifically, in some embodiments of the present invention, the process equipment for the thin film deposition process can be determined first. Based on the actual state of each equipment, test data for that equipment is obtained. This test data may include a first RF current value and a second RF current value during the test. Then, based on the first and second RF current values, a univariate experiment can be performed to measure the output values ​​from the CEX output points 212 and 222 of the RF generator.

[0084] Specifically, a first fitting formula and a second fitting formula can be obtained based on the first radio frequency current value and the second radio frequency current value. The first fitting formula may include the relationship between the phase angle of the first radio frequency current and the current, and the second fitting formula may include the relationship between the phase angle of the second radio frequency current and the current.

[0085] Specifically, the formula for the first fitting equation can be as follows:

[0086] offset1 = AI1 + B

[0087] Where offset1 represents the phase compensation value of the first RF current, I1 represents the first RF current value, A is the proportional coefficient, and B is the offset compensation. The formula for the second fitting formula can be as follows:

[0088] offset2 = CI2 + D

[0089] Where offset2 represents the phase compensation value of the second RF current, I2 represents the value of the second RF current, C is the proportional coefficient, and D is the offset compensation.

[0090] By using the test data of the first and second radio frequency currents described above, the phase angle and current relationship of the first radio frequency current in the first reaction cavity 110 and the phase angle and current relationship of the second radio frequency current in the second reaction cavity 120 in the current semiconductor device process equipment 100 can be obtained. For example, in some optional embodiments, the phase angle and current relationship of the first radio frequency current in the first reaction cavity 110 can be offset1 = -0.2I1 + 13.23, and the phase angle and current relationship of the second radio frequency current in the second reaction cavity 120 can be offset2 = 0.47I2 + 12.37.

[0091] Then, as Figure 4 As shown, steps S430 and S440 can be executed to substitute the RF current ratio into the first fitting formula and the second fitting formula, thereby obtaining the phase synchronization compensation value (CEX offset) between the second RF current output by the second RF generator 220 and the first RF current output by the first RF generator 210.

[0092] Specifically, please see Figure 5A , Figure 5A A schematic diagram of the phase angle and current curves of a first radio frequency power supply and a second radio frequency power supply provided according to some embodiments of the present invention is shown.

[0093] like Figure 5A As shown, in some embodiments, the vertical axis refers to the current value on the heating plate, and the horizontal axis represents the phase synchronization compensation value (CEX offset value). "Off" indicates that the phase synchronization function is disabled. "First reaction chamber / Second reaction chamber" means that only one reaction chamber is active for radio frequency (RF), while the RF system of the other reaction chamber is disabled. Curve 510 represents the current change of the heating plate in the first reaction chamber 110, and curve 520 represents the current change of the heating plate in the second reaction chamber 120. It can be seen that under different phase synchronization compensation values, the RF current flowing through the lower electrode between different chambers is inconsistent. The current is consistent when the phase difference is 0 and when the function is not enabled, indicating that the effect is not caused by the CEX function being enabled.

[0094] In some preferred embodiments, the test data may further include the first film thickness test value deposited in the first reaction chamber 110 and the second film thickness test value deposited in the second reaction chamber 120. After obtaining the first fitting formula and the second fitting formula, the method may further include: based on the first and second fitting formulas, performing a second fitting based on the first and second film thickness test values ​​to obtain a third fitting formula and a fourth fitting formula. The third fitting formula may include the phase angle, film thickness, and current relationship of the first RF current, and the fourth fitting formula may include the phase angle, film thickness, and current relationship of the second RF current. In other words, a fitting formula suitable for the current equipment can be fitted through a second fitting based on different phase test data, film thickness test data, and current test data.

[0095] Specifically, please see Figure 5B , Figure 5B A schematic diagram of the phase angle and film thickness of a first radio frequency power supply and a second radio frequency power supply provided according to some embodiments of the present invention is shown.

[0096] like Figure 5B As shown, in some other embodiments, the vertical axis refers to the thickness of the process film. The horizontal axis represents the phase synchronization compensation value (CEX offset value), with "off" indicating that the phase synchronization function is disabled. The first / second reaction chamber represents the RF operation within a single reaction chamber, while the RF system of the other reaction chamber is disabled. Curve 530 represents the film thickness within the first reaction chamber 110, and curve 540 represents the film thickness within the second reaction chamber 120. It can be seen that under different phase synchronization compensation values, the film deposition rate of different chambers is inconsistent, resulting in inconsistent film thickness. The consistency between the phase difference (0) and the state without the function indicates that the effect is not caused by the CEX function being enabled. Furthermore, it can be seen that the magnitude of the RF current at the lower electrode affects the film thickness.

[0097] Furthermore, in addition to, Figure 5A and 5B The first, second, third, and fourth fitting formulas, which are derived from the current and film thickness corresponding to the two sets of data (cex0 and cex90), can also be used to perform more parameter tests to more accurately fit the machine fitting formulas that include more process parameters.

[0098] Please return Figure 3 As shown, step S340 can then be performed: providing the target radio frequency current via the first radio frequency generator.

[0099] Specifically, the controller can control the first RF generator 210 to output a first RF current as the target RF current.

[0100] Then step S350 can be performed: based on the target RF current and phase synchronization compensation value, adjust the first RF current value and the second RF current value to make the thin film deposition rate in the first reaction chamber and the second reaction chamber consistent.

[0101] Specifically, such as Figure 2 As shown, in some embodiments, a phase synchronization compensation value between the second RF current and the target RF current can be assigned to the second RF generator 220. Then, the controller can synchronously adjust the first RF current value and the second RF current value of the first RF generator 210 and the second RF generator 220 according to the phase synchronization compensation value of the second RF current, so that the adjusted first RF current value and the second RF current value tend to be consistent. In embodiments of the present invention, adjusting the output energy of the RF generator can change the thickness (THK) of the deposited thin film. Although the phase synchronization compensation value is for the second RF current, if only the phase value of the second RF generator 220 is adjusted, it will simultaneously affect the current in the lower electrode heating plate in both reaction chambers. Because the RF phases in the two reaction chambers have different differences, the RF paths of the two reaction chambers will change at the same time, thereby affecting the RF current of the lower electrode.

[0102] In this embodiment, the film deposition rate on the heating plates in the two reaction chambers can be adjusted by regulating the first radio frequency current value on the first heating plate and the second radio frequency current value on the second heating plate. When the radio frequency current value increases, the film deposition rate on the heating plate increases; conversely, when the radio frequency current value decreases, the film deposition rate on the heating plate decreases, thereby achieving the effect of real-time fine-tuning of the deposition rate.

[0103] When the adjusted first radio frequency current value on the first heating plate and the second radio frequency current value on the second heating plate are consistent, the thin film deposition rate in the first reaction chamber 110 and the second reaction chamber 120 are consistent, thereby further reducing the process error (mismatch) between the chambers.

[0104] Those skilled in the art will understand that the above-described scheme of using the first radio frequency current output by the first radio frequency generator 210 as the target radio frequency current is merely a non-limiting implementation provided by the present invention. It is intended to clearly demonstrate the main concept of the invention and provide a specific solution that is easy for the public to implement, rather than to limit the scope of protection of the invention. Optionally, in alternative embodiments, those skilled in the art can also use the second radio frequency current output by the second radio frequency generator 220 as the target radio frequency current based on the concept of the present invention to obtain the phase synchronization compensation value of the first radio frequency current, thereby achieving the same technical effect.

[0105] In the above embodiments of the present invention, the RF loop adjustment system 200 set between the RF generators of the two reaction cavities can automatically adjust the phase difference of the RF signal in real time based on the process performance within the two reaction cavities, so that the RF current values ​​within the two reaction cavities are basically consistent. This can solve the process error caused by slight differences in the RF loops between multiple cavities and can meet the parameter settings in different process processes. It also provides an additional means of adjusting the machine when recipe settings are not allowed.

[0106] Those skilled in the art will understand that the above-described semiconductor device process equipment 100 including two reaction chambers is merely a non-limiting embodiment provided by the present invention, intended to clearly demonstrate the main concept of the invention and provide a specific solution convenient for public implementation, rather than being used to limit the scope of protection of the invention. The semiconductor device process equipment 100 may also include multiple reaction chambers. Those skilled in the art can also adjust the phase synchronization of the radio frequency power signals within the multiple reaction chambers based on the concept of the present invention to prevent crosstalk between the multiple chambers and improve the film deposition quality within the multiple chambers.

[0107] Although the methods described above are illustrated and depicted as a series of actions for the sake of simplicity, it should be understood and appreciated that these methods are not limited by the order of the actions, as some actions may occur in a different order and / or concurrently with other actions from the illustrations and descriptions herein or not illustrated and described herein but which may be understood by those skilled in the art, according to one or more embodiments.

[0108] Those skilled in the art will further appreciate that the steps of the methods or algorithms described in connection with the embodiments disclosed herein can be embodied directly in hardware, in a software module executed by a processor, or in a combination of both. The software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor so that the processor can read and write information to / from the storage medium. In an alternative, the storage medium may be integrated into the processor. The processor and storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In an alternative, the processor and storage medium may reside as discrete components in the user terminal.

[0109] In one or more exemplary embodiments, the described functionality may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software as a computer program product, the functionality may be stored or transmitted as one or more instructions or code on or through a computer-readable medium. A computer-readable medium includes both computer storage media and communication media, encompassing any medium that facilitates the transfer of a computer program from one location to another. A storage medium may be any available medium accessible to a computer. By way of example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and is accessible to a computer. Any connection is also legitimately referred to as a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of a medium. As used in this article, disk and disc include compact discs (CDs), laser discs, optical discs, digital multi-purpose discs (DVDs), floppy disks, and Blu-ray discs. Disks typically reproduce data magnetically, while discs reproduce data optically using lasers. Combinations of these should also be included within the scope of computer-readable media.

[0110] In summary, the present invention provides an RF circuit adjustment system, a semiconductor device process equipment, an RF circuit adjustment method, and a computer-readable storage medium, which can automatically and in real time adjust the phase uniformity of the RF power signals in each reaction chamber without adjusting the parameter settings during the process, thereby reducing crosstalk between chambers. It can also adjust the film deposition rate in real time, thereby making the film deposition rate of each chamber consistent and reducing process errors.

[0111] The prior description of this disclosure is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not intended to be limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A radio frequency loop adjustment system, characterized by, The method comprises: a first radio frequency generator and a second radio frequency generator, respectively configured to provide a first radio frequency current value to a first reaction cavity and a second radio frequency current value to a second reaction cavity; a current detection device configured to collect the first radio frequency current value and the second radio frequency current value; a controller configured to: based on the first radio frequency current value and the second radio frequency current value, obtain a radio frequency current ratio of the first radio frequency current and the second radio frequency current; substitute the radio frequency current ratio into a first fitting formula and a second fitting formula to obtain a phase synchronization compensation value of the second radio frequency current, wherein the first fitting formula indicates a proportional relationship between a phase compensation value of the first radio frequency current and the first radio frequency current value and an offset compensation thereof, and the second fitting formula indicates a proportional relationship between a phase compensation value of the second radio frequency current and the second radio frequency current value and an offset compensation thereof; provide a target radio frequency current via the first radio frequency generator; assign the phase synchronization compensation value between the second radio frequency current and the target radio frequency current to the second radio frequency generator; synchronously adjust the first radio frequency current value and the second radio frequency current value to make the first radio frequency current value and the second radio frequency current value consistent; and in response to the first radio frequency current value and the second radio frequency current value reaching consistency, make the thin film deposition rates in the first reaction cavity and the second reaction cavity consistent. Further comprising:

2. The radio frequency loop adjustment system of claim 1, wherein, a signal separator coupled with the first radio frequency generator and the second radio frequency generator, the controller is further configured to: in a machine test process, generate a first radio frequency power signal provided to the first reaction cavity and a second radio frequency power signal provided to the second reaction cavity via the signal separator. The step of generating the first radio frequency power signal provided to the first reaction cavity and the second radio frequency power signal provided to the second reaction cavity via the signal separator in the machine test process comprises:

3. The radio frequency loop adjustment system of claim 2, wherein, the first radio frequency generator outputs a sinusoidal wave signal as a phase synchronization reference signal of the two reaction cavities; and via the signal separator, the sinusoidal wave signal is divided into two synchronization signals, which are output back to the first radio frequency generator as the first radio frequency power signal and to the second radio frequency generator as the second radio frequency power signal. The step of obtaining the radio frequency current ratio of the first radio frequency current and the second radio frequency current based on the first radio frequency current value and the second radio frequency current value comprises:

4. The radio frequency loop adjustment system of claim 3, wherein, obtaining the first radio frequency current value of the first radio frequency power signal and the second radio frequency current value of the second radio frequency power signal by the current detection device; and obtaining the radio frequency current ratio of the first radio frequency current and the second radio frequency current, wherein the formula of the radio frequency current ratio is as follows: ​ wherein, denotes the first radio frequency current value, denotes the second radio frequency current value, denotes an offset compensation.

5. The radio frequency loop adjustment system of claim 3, wherein, The first radio frequency generator and the second radio frequency generator are respectively connected to the heating discs in the respective reaction cavities, and the thin film deposition rate on the first heating disc and the thin film deposition rate on the second heating disc are adjusted by adjusting the first radio frequency current on the first heating disc and the second radio frequency current on the second heating disc.

6. The radio frequency loop adjustment system of claim 3, wherein, The radio frequency line length of the signal separator to the CEX feed-in point of the first radio frequency generator is consistent with the radio frequency line length of the signal separator to the CEX feed-in point of the second radio frequency generator.

7. The radio frequency loop adjustment system of claim 3, wherein, The step of substituting the radio frequency current ratio into the first fitting formula and the second fitting formula to obtain the phase synchronization compensation value of the second radio frequency current comprises: Obtaining test data of the machine, wherein the test data comprises the first radio frequency current value and the second radio frequency current value during the test; Based on the first radio frequency current value and the second radio frequency current value, obtaining the first fitting formula and the second fitting formula, wherein the formula of the first fitting formula is as follows: wherein denotes a phase compensation value of the first radio frequency current, denotes a first radio frequency current value, is a proportional factor, is an offset compensation, The formula of the second fitting formula is as follows: wherein denotes a phase compensation value of the second radio frequency current, denotes a second radio frequency current value, is a proportional factor, is an offset compensation; and Substituting the radio frequency current ratio into the first fitting formula and the second fitting formula to obtain the phase synchronization compensation value.

8. The radio frequency loop adjustment system of claim 7, wherein, The test data further comprises a first film thickness test value in the first reaction cavity and a second film thickness test value in the second reaction cavity, and the step of obtaining the first fitting formula and the second fitting formula further comprises: Based on the first film thickness test value and the second film thickness test value, secondary fitting is performed based on the first fitting formula and the second fitting formula to obtain a third fitting formula and a fourth fitting formula, wherein the third fitting formula comprises the phase angle, film thickness and current relationship of the first radio frequency current, and the fourth fitting formula comprises the phase angle, film thickness and current relationship of the second radio frequency current.

9. A process tool for semiconductor devices, characterized by, Comprise: Two reaction cavities, each of which performs a thin film deposition process, wherein the upper electrodes in the two reaction cavities are located in the same shielding cover; An isolation cover plate is arranged between the two reaction cavities for isolating the radio frequency signal interference between the two reaction cavities; and The radio frequency loop adjustment system according to any one of claims 1-8 is used to adjust the first radio frequency current value in the first reaction cavity and the radio frequency current value in the second reaction cavity, so that the thin film deposition rates in the first reaction cavity and the second reaction cavity are consistent.

10. A radio frequency loop adjustment method, characterized by, Comprise the following steps: The first radio frequency generator and the second radio frequency generator in the radio frequency loop adjustment system in the process machine of the semiconductor device according to claim 9 are used to respectively provide a first radio frequency current value to the first reaction cavity and a second radio frequency current value to the second reaction cavity; Based on the first radio frequency current value and the second radio frequency current value, a radio frequency current ratio of the first radio frequency current and the second radio frequency current is obtained; The radio frequency loop adjustment system according to any one of claims 1-8 is used to adjust the first radio frequency current value in the first reaction cavity and the radio frequency current value in the second reaction cavity, so that the thin film deposition rates in the first reaction cavity and the second reaction cavity are consistent. substituting the radio frequency current ratio into a first fitting formula and a second fitting formula to obtain a phase synchronization compensation value of the second radio frequency current, wherein the first fitting formula indicates a proportional relationship between a phase compensation value of the first radio frequency current and the first radio frequency current value and offset compensation thereof, and the second fitting formula indicates a proportional relationship between a phase compensation value of the second radio frequency current and the second radio frequency current value and offset compensation thereof; providing a target radio frequency current via the first radio frequency generator; and assigning a phase synchronization compensation value between the second radio frequency current and the target radio frequency current to the second radio frequency generator; synchronously adjusting the first radio frequency current value and the second radio frequency current value to make the first radio frequency current value and the second radio frequency current value consistent; and in response to the first radio frequency current value and the second radio frequency current value reaching consistency, the thin film deposition rate in the first reaction cavity and the second reaction cavity is consistent.

11. A computer readable storage medium having stored thereon computer instructions, wherein, The computer instructions are executed by the processor to implement the radio frequency loop adjustment method of claim 10.

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