TWI807210B - Inductively coupled plasma treatment device and ignition control method thereof - Google Patents

Abstract

The invention provides an ignition control method for an inductively coupled plasma processing device. The device has a vacuum processing chamber, a radio frequency power source, and a bias power source. The radio frequency power source couples a radio frequency signal to the vacuum processing chamber through an inductive coupling coil. The bias power source applies a bias signal to a base inside the vacuum processing chamber through a radio frequency matching network, and the base is used to support a substrate to be processed. The method includes: obtaining a control command; Plasma ignition. By applying the method provided by the present invention, by controlling the turn-on time of the radio frequency power source and the bias power source, and adjusting the duty cycle and voltage magnitude of the pulse voltage of the bias power source, it is possible to further realize uniform acceleration of the plasma while realizing efficient ignition.

Description

Inductively coupled plasma treatment device and ignition control method thereof

The present invention relates to the technical field of plasma treatment, and more specifically, relates to an inductively coupled plasma treatment device and an ignition control method thereof.

In a plasma processing apparatus, an RF power supply supplies power to a process chamber to generate a plasma. Plasma contains a large number of active particles such as electrons, ions, excited atoms, molecules, and free radicals. These active particles interact with the wafer or components to be processed placed in the chamber and exposed to the plasma environment, causing plasma reactions on the surface to change the surface properties of the wafer or components, thereby completing plasma etching or other processes.

In the above plasma processing device, the Inductively Coupled Plasma (ICP) processing device couples radio frequency power into the processing chamber of the processing device by providing an induction coil outside the processing device. In the ICP technology, there is a discharge caused by the electric field generated by the charge on the surface of the induction coil, that is, capacitive coupling, and a discharge caused by the magnetic field generated by the induction coil, that is, inductive coupling. In the process of plasma ignition and formation, the high voltage generated in the processing chamber by capacitive coupling is of great help to ignite the plasma and help the start of inductive discharge. However, when the plasma is ignited to process the substrate, since the capacitive discharge attached to the induction coil is uneven, this will cause the electric field on the induction coil to accelerate the plasma unevenly, which in turn leads to uneven treatment of the substrate by the plasma.

In order to avoid the uneven consequences caused by the capacitive coupling phenomenon in the plasma treatment process, the technicians have carried out a series of modifications to the shape of the induction coil, which can effectively reduce the voltage on the branches of each induction coil, thereby effectively suppressing the capacitive coupling caused by the high voltage on the induction coil, so as to ensure the uniform treatment of the substrate by the plasma. However, the reduction of capacitive coupling makes it difficult to ignite the plasma under the condition of generating low-pressure and low-density plasma.

In view of this, an embodiment of the present invention provides an inductively coupled plasma processing device and an ignition control method thereof, so as to achieve high-efficiency ignition and further uniform acceleration of plasma.

In order to achieve the above purpose, embodiments of the present invention provide the following technical solutions:

An ignition control method for an inductively coupled plasma processing device. The device has a vacuum processing chamber, a radio frequency power source, and a bias power source. The radio frequency power source couples a radio frequency signal into the vacuum processing chamber through an inductive coupling coil. The bias power source applies a bias signal to a base inside the vacuum processing chamber through a radio frequency matching network, and the base is used to support a substrate to be processed. The method includes: obtaining a control instruction; ignition.

Preferably, the bias power source executes the control command to generate the bias signal, including: executing the control command and turning on the bias power source to generate the bias signal; after turning on the bias power source for a set time, turn on the radio frequency power source to generate the radio frequency signal.

Preferably, in the above method, the setting time is less than 200ms.

Preferably, in the above method, the duty cycle of the pulse voltage is set to be lower than 10%.

Preferably, in the above method, the bias power of the pulse voltage is set to be less than 50 watts.

Preferably, in the above method, the plasma formation process includes: setting the time elapsed from turning on the radio frequency power source to generating the plasma in the vacuum processing chamber as T, and the pulse width of the pulse voltage as 0.1T-10T.

Preferably, in the above method, the process of forming the plasma includes: the time elapsed from the opening of the radio frequency power source to the generation of the plasma in the vacuum processing chamber is T, the opening time of the bias power source is not later than the opening time of the radio frequency power source, and the opening time is not less than T.

Preferably, in the above method, the inductively coupled coil is a combination of multiple single-turn coils or a combination of multiple half-turn coils.

The present invention further provides an inductively coupled plasma processing device, comprising: a vacuum processing chamber, a radio frequency power source, and a bias power source; the radio frequency power source couples a radio frequency signal into the vacuum processing chamber through an inductively coupled coil, and the bias power source applies a bias signal to a base inside the vacuum processing chamber through a radio frequency matching network, and the base is used to support a substrate to be processed; wherein, the bias power source is used to execute a control command to generate a bias signal; the bias signal is a pulse voltage, and is used to ignite the plasma together with the radio frequency signal.

Preferably, in the above device, the inductively coupled coil is a combination of multiple single-turn coils or a combination of multiple half-turn coils.

It can be seen from the above description that in the inductively coupled plasma processing device and its ignition control method provided by the technical solution of the present invention, the pulse voltage output by the bias power source can be used as a bias signal to ignite the plasma together with the radio frequency signal. In the prior art, in order to achieve the purpose of uniform acceleration, the coil structure needs to be changed. Although the capacitive coupling is weakened or even eliminated to achieve the purpose of uniform acceleration, it will make it difficult to ignite. The present invention uses the pulse voltage generated by the bias power source as the bias voltage The signal can assist the ignition, which solves the above problems. By applying the method provided by the present invention, by controlling the turn-on time of the radio frequency power source and the bias power source, and adjusting the duty cycle and voltage magnitude of the pulse voltage of the bias power source, it is possible to further realize uniform acceleration of the plasma while realizing efficient ignition.

10: Gas supply device

100: vacuum processing chamber

105: side wall of processing chamber

110: Base

115: electrostatic chuck

116: Voltage measuring device

120: Substrate

125:Exhaust pump

130: insulation window

140: Inductive coupling coil

145: RF power source

146: Bias power source

150: gas injection inlet

160: Plasma

200: RF matching network

201, 202: variable capacitance

A,B,C: stage

P _Fwd : incident power

P _Ref : reflected power

L: inductance

Rs: resistance

S201, S202: steps

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that are required in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only the embodiments of the present invention. For those skilled in the art, other drawings can be further obtained according to the provided drawings without creative work.

Fig. 1 is a schematic structural diagram of an inductively coupled plasma processing device provided by the present invention; Fig. 2 is a method flow chart of an ignition control method of an inductively coupled plasma processing device provided by the present invention; Fig. 3 is a reflected power model diagram of a radio frequency power source when an inductively coupled plasma is ignited according to the present invention; Fig. 4 is a pulse voltage model diagram at the beginning of an inductively coupled plasma ignition provided by the present invention; Fig. 5 is a circuit diagram of a radio frequency matching network connected to a bias power source provided by an embodiment of the present invention.

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the illustrated embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts fall within the protection scope of the present invention.

In this disclosure, the terms "comprising", "comprising" or any other variation thereof are intended to cover a non-exclusive inclusion such that a process, method, article or apparatus comprising a series of elements includes not only those elements but also further includes other elements not expressly listed or is further included as an inherent element of such process, method, article or apparatus. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the further presence of additional identical elements in the process, method, article or apparatus comprising said element.

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in FIG. 1 , FIG. 1 is a schematic structural view of an inductively coupled plasma processing device provided by the present invention. In FIG. 1 , the inductively coupled plasma reaction device includes a vacuum processing chamber 100, and the vacuum processing chamber 100 includes a cylindrical or approximately cylindrical processing chamber side wall 105 made of a metal material. An insulating window 130 is arranged above the processing chamber side wall 105. An inductively coupled coil 140 is arranged above the insulating window 130. The inductively coupled coil 140 is connected to a radio frequency power source 145. The sidewall 105 of the processing chamber is adjacent to the gas injection port 150 disposed at one end of the insulating window 130 , and the gas injection port 150 is connected to the gas supply device 10 . A base 110 is provided at a downstream position inside the vacuum processing chamber 100 , and an electrostatic chuck 115 is placed on the base 110 for supporting and fixing the substrate 120 . An exhaust pump 125 is further provided below the vacuum processing chamber 100 for discharging the reaction by-products out of the vacuum processing chamber 100 . An RF matching network 200 is provided between the RF bias power source 146 and the susceptor 110 for maximizing the output power of the RF power source 145 applied to the vacuum processing chamber 100 . In addition, a voltage measuring device 116 is further provided on the surface of the electrostatic chuck 115 for measuring the voltage on the surface of the substrate 120 .

Before the processing process starts, the substrate 120 is moved to the electrostatic chuck 115 above the susceptor 110 and fixed, the reaction gas in the gas supply device 10 enters the vacuum processing chamber 100 through the gas injection port 150, and then the RF power source 145 is applied to the inductively coupled coil 140. In the prior art, the inductively coupled coil 140 is a multi-turn single coil structure, and this coil structure can generate a relatively A large radio frequency voltage is used to help the inductive discharge generated by the radio frequency power source 145 on the coil to ignite the reaction gas in the vacuum processing chamber 100. The radio frequency power of the radio frequency power source 145 drives the inductively coupled coil 140 to generate a strong high frequency alternating magnetic field, so that the low pressure reaction gas is ionized to generate plasma 160. Plasma 160 contains a large number of active particles such as electrons, ions, excited atoms, molecules and free radicals. The above-mentioned active particles can undergo various physical and chemical reactions with the surface of the substrate 120 to be processed, so that the morphology of the surface of the substrate 120 changes, that is, the etching process is completed.

However, according to the prior art, the capacitive coupling reaction generated by the multi-turn single inductively coupled coil 140 has a negative impact on the uniformity of the processing of the substrate 120, that is, the capacitive discharge attached to the inductively coupled coil 140 is uneven, causing the electric field on the inductively coupled coil 140 to accelerate the plasma 160 unevenly, which in turn leads to uneven processing results of the plasma 160 on the substrate 120. It is possible to reduce or eliminate the capacitive discharge generated by the inductive coupling coil 140 by changing the structure of the inductive coupling coil 140, so as to ensure the uniformity of the substrate 120 processing. However, although the structure of multiple single-turn coil combinations or multiple half-turn coil combinations adopted in the present invention can increase the uniform acceleration of the plasma 160 and ensure the uniformity of the substrate 120 processing, it is difficult to ignite the reactive gas in the vacuum processing chamber 100 when the plasma is ignited under low pressure and low density conditions due to the reduction of the capacitive discharge generated by the inductively coupled coil 140.

It should be noted that, in order to reduce or eliminate the capacitive discharge generated by the inductive coupling coil 140 , the adopted structure of the inductive coupling coil 140 includes but is not limited to a combination of a plurality of single-turn coils or a plurality of half-turn coils.

In order to solve the problem that the plasma in the inductively coupled plasma processing device of the present invention is difficult to ignite, the present invention provides a method of applying a control command to the bias power source to assist in igniting the plasma. In the plasma etching process, the RF power source 145 is applied to the inductively coupled coil 140, which is mainly used to control the plasma dissociation or plasma density. The RF bias power source 146 applies a control command to apply the generated bias signal pulse mode to the susceptor 110. The function of the bias power source 146 is to control the ion energy. quantity and its energy distribution. Before performing the plasma etching step on the substrate 120 , the reaction gas in the vacuum processing chamber 100 must be dissociated into plasma. The role of the bias power source 146 in the process of igniting the plasma is to generate a bias signal in the vacuum processing chamber 100, and assist the radio frequency signal of the radio frequency power source 145 to ignite the plasma with the pulse voltage of the bias signal pulse mode.

As shown in Figure 2, Figure 2 is a method flow chart of an ignition control method for an inductively coupled plasma processing device provided by the present invention, which is used for the device shown in Figure 1. Specifically, the control method includes:

Step S201: Obtain a control instruction.

In the method provided by the embodiment of the present invention, when the plasma is difficult to ignite under the condition of low pressure and low density of the reaction gas in the vacuum processing chamber, the bias power source is triggered to obtain the control command.

In one way, the device further includes a controller electrically connected to the bias power source, and the controller can generate a control instruction in response to a signal generated by a sensor in the inductively coupled plasma processing device being triggered. In another manner, it is also possible to directly input control instructions to the bias power source manually.

Step S202: The bias power source executes the control command to generate a bias signal; wherein, the bias signal is a pulse voltage and is used to ignite the plasma together with the radio frequency signal.

In the method provided by the embodiment of the present invention, after the bias power source obtains the control command, the bias power source executes the control command, and turns on the bias power source to generate a bias signal, and sets the bias signal as a pulse voltage in a pulse mode, which is used to ignite the plasma together with the radio frequency signal. Wherein, the radio frequency signal is generated by a radio frequency power source. In the embodiment of the present invention, the pulse voltage is used as the bias signal to assist ignition. It should be noted that, in other modes, the bias signal can also be a continuous wave mode.

In the method provided by the embodiment of the present invention, by applying a control command to the bias power source of the inductively coupled plasma processing device, the bias power source is used to execute the control command to make it generate a bias signal, and set the bias signal to a pulse voltage in a pulse mode, and in the subsequent processing process, The ignition of plasma is assisted by pulse voltage and radio frequency signal. By applying the method provided by the invention, the ignition performance of the plasma is improved and the ignition of the plasma is ensured.

As shown in Fig. 3, Fig. 3 is a reflection power model diagram of a radio frequency power source provided by the present invention when inductively coupled plasma is ignited, specifically including: the horizontal axis in the figure is time t (ms), and the vertical axis is power P (w). In the figure, P _Fwd is the incident power, that is, the output power of the RF power source, which remains stable throughout the ignition process. P _Ref is the reflected power, that is, the part of the reflected power detected by the RF power source after being reflected and not completely absorbed after the output of the RF power source.階段A表示電漿形成和穩定的過程，該階段反射功率P _Ref的值約等於入射功率P _Fwd的值，也就是說在未產生電漿時，沒有對射頻功率的利用，射頻功率源輸出的功率相當於全部反射回去，故反射功率P _Ref的值約等於入射功率P _Fwd的值，在階段A和階段B的交界時刻完成點火，產生電漿，電漿吸收能量，導致反射功率降低，故產生階段A到階段B的反射功率跳變，在階段C調節射頻功率源與耦合線圈之間的匹配網路，使得反射功率進一步降低；階段B表示為電漿點火後，在調節阻抗匹配之前的階段，階段C表示為透過匹配網路調節射頻訊號進行阻抗匹配的階段，以提高對射頻功率源的功率利用率。

In the process of plasma ignition, a high electric field is crucial for accelerating the initial electrons of plasma discharge, and the higher the voltage applied to the reaction chamber, the more helpful it is for plasma ignition. If the plasma fails to ignite, phase A will be extended so that the plasma cannot transition to phase B. The pulse voltage frequency of the bias signal is of the same order of magnitude as phase A. In theory, in terms of the contribution to ignition, there is no need to apply a bias signal to phase B and phase C. However, the accuracy of existing hardware control makes the bias signal action time not accurate enough to be effective only in phase A, so the turn-on time of the bias power source can be made to at least cover phase A, so that the bias signal is at least applied to the entire phase A to complete the ignition. And turn off at least after the transition to stage B, so specifically the pulse voltage can be turned off in stage B or in stage C. if stage The duration of A is T, and the pulse width of the pulse voltage is 0.1T-10T. The specific time of the pulse width of the pulse voltage can be set based on requirements, and is not limited to the above range. As shown in Figure 3, T=xms, for example, x can be 0.2ms, 1ms or 2ms. In addition, in the drawing, the duration of stage A to stage B is 10 ms, and the duration of stage A to stage B to stage C is less than 1000 ms.

In the actual process operation, the ignition phase A time is relatively short, usually only a few milliseconds, and limited by hardware technology, it takes several seconds for the RF power supply to switch between different output voltages. Therefore, if the bias RF power supply is set at a higher output voltage during the ignition phase, due to the short ignition phase time, the higher bias RF voltage will continue to phase B and phase C, which will have a negative impact on the process processing of phase B and phase C. In order to improve the ignition performance of the plasma, during the formation of the plasma in stage A, on the one hand, the duty cycle of the pulse voltage is set to less than 10%, and the power value is less than 50 watts, and is transmitted to the vacuum processing chamber in a pulse mode. In this way, through a smaller duty cycle, the higher output voltage of the bias RF power supply can be used to improve the ignition effect without increasing the overall power of the ignition stage. At the same time, the impact of high output power on the processes of stages B and C can be effectively avoided. In addition, in the absence of plasma, relatively small pulse voltages can generate high voltages in the cavity to accelerate initial electrons. On the other hand, after the bias power source is turned on in advance and the time is set, the radio frequency power source is turned on. Wherein, the setting time is less than 200 ms, if the setting time can be less than 20 ms, then the setting time can be set based on requirements, and is not limited to the above range. When the time T elapses from turning on the RF power source to generating plasma in the vacuum processing chamber, the turn-on time of the bias power source is not later than the turn-on time of the RF power source, and the turn-on duration is not less than T. The bias power source can be turned on in advance based on requirements. For example, T can be 15ms or 10ms. In other ways, it can also be turned on synchronously with the radio frequency power source or later than the radio frequency power source. It is known that turning on in advance can achieve the purpose of fast ignition, so the present disclosure preferentially sets the bias power source to turn on in advance.

In addition, it should be noted that the duty cycle of the pulse voltage is not limited to less than 10%, the duty cycle can be set based on demand, not limited to the above range, and can also be higher than 10%; the bias power of the pulse voltage is not limited to less than 50 watts, the bias power can be set based on demand, not limited to the above range, or It can be greater than 50 watts; the turn-on time of the bias power source is not limited to be earlier than the turn-on time of the radio frequency power source, but also can be later than the turn-on time of the radio frequency power source or the bias power source and the radio frequency power source are turned on synchronously. The process parameters of the bias power source can be preset through control commands, and the process parameters such as pulse voltage cycle, duty cycle, and power can be set. These parameters can be set based on actual needs, including but not limited to the example values described in the embodiments of the present disclosure.

As shown in Fig. 4, Fig. 4 is a pulse voltage model diagram at the beginning of ignition of an inductively coupled plasma provided by the present invention.

As shown in the figure, it specifically includes: the horizontal axis in the figure is time t (ms), and the vertical axis is power P (w). In the figure, P _Fwd is the incident power, that is, the output power of the RF power source, which remains stable throughout the ignition process. P _Ref is the reflected power, that is, the part that is not completely absorbed after the output of the RF power source and is detected by the RF power source after reflection. Stage A represents the process of plasma formation and stabilization. In this stage, the value of reflected power P _Ref is approximately equal to the value of incident power P _Fwd . Ignition is completed at the junction of stage A and stage B, and plasma is generated. The plasma absorbs energy, resulting in a decrease in reflected power. Therefore, a jump in reflected power from stage A to stage B occurs. Stage B represents the stage after the plasma is ignited and before impedance matching is adjusted. As shown in Figure 4, T=xms, for example, x can be 0.2ms, 1ms or 2ms. In the figure, the duration of phase A to phase B is 10 ms. In addition, the lower figure in Fig. 4 shows the pulse model generated by the incident power _PFwd changing with time T.

Based on the above-mentioned embodiment of the ignition control method, another embodiment of the present invention further provides an inductively coupled plasma processing device for realizing the above-mentioned ignition control method. The inductively coupled plasma processing device is shown in FIG. On the inner base 110, the base 110 is used to support the substrate 120 to be processed; wherein, the bias power source 146 is used to perform control command to generate a bias signal; the bias signal is a pulse voltage and is used for plasma ignition together with the radio frequency signal.

Wherein, the inductively coupled coil 140 is a combination of multiple single-turn coils or a combination of multiple half-turn coils.

Applying the inductively coupled plasma processing device provided by the embodiment of the present invention can improve the plasma ignition performance and ensure the plasma ignition by controlling the turn-on time of the radio frequency power source and the bias power source, and adjusting the duty cycle and voltage magnitude of the pulse voltage.

It should be noted that, as shown in FIG. 1, a radio frequency matching network 200 is provided between the radio frequency bias power source 146 and the base 110. The structure of the radio frequency matching network 200 is shown in FIG. 5. FIG. When there is plasma in the vacuum processing chamber 100, the load impedance is the sum of the impedances of the vacuum processing chamber 100, the electrostatic chuck 115, and the plasma; when there is no plasma in the vacuum processing chamber 100, the load impedance is the sum of the impedances of the vacuum processing chamber 100 and the electrostatic chuck 115.

As shown in FIG. 5 , the radio frequency matching network 200 includes: a variable capacitor 201 and a variable capacitor 202 . The output end of the bias power source 146 is grounded through the variable capacitor 201 and connected to the load impedance through the variable capacitor 202 . By adjusting the variable capacitor 201 and/or the variable capacitor 202, the amplitude of the pulse voltage output by the bias power source 146 can be adjusted to control the voltage applied to the surface of the susceptor and assist plasma ignition.

Optionally, the radio frequency matching network 200 further includes a resistor Rs and an inductor L. The output terminal of the bias power source 146 is connected to the ground through the resistor Rs and the variable capacitor 201 through the resistor Rs and the variable capacitor 201 , and the output terminal of the bias power source 146 is connected to the load impedance through the resistor Rs, the inductor L and the variable capacitor 202 in sequence.

Based on the embodiment of the radio frequency matching network 200, there is another matching network between the radio frequency power source 145 and the inductively coupled coil 140. After the plasma ignition is completed, in the above control method, the One step is to adjust the matching network to improve the power utilization rate of the radio frequency power source. The matching network is not shown in the figure. The implementation of the matching network can refer to the radio frequency matching network 200 , which will not be repeated here.

It can be seen from the above description that in the method provided by the embodiment of the present invention, a control command is applied to the bias power source of the inductively coupled plasma processing device, and the bias power source is used to execute the control command to generate a bias signal, and the bias signal is set as a pulse voltage in a pulse mode, and in the subsequent processing process, the pulse voltage and the radio frequency signal are used to assist the ignition of the plasma. By applying the method provided by the invention, the ignition performance of the plasma is improved and the ignition of the plasma is ensured.

Each embodiment in this specification is described in a progressive, parallel, or a combination of parallel and progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the related part can be referred to the description of the method part.

It should be further noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Furthermore, the terms "comprising", "comprising" or any other variation thereof are intended to cover a non-exclusive inclusion such that an article or device comprising a series of elements includes not only those elements but also further includes other elements not expressly listed or is further inherent to such an article or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the further presence of additional identical elements in an article or device comprising said element.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these examples will be readily apparent to those of ordinary skill in the art, and the general principles defined herein can be made without departing from the spirit or scope of the invention. case, implemented in other embodiments. Thus, the present invention will not be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

S201, S202: steps

Claims (8)

An ignition control method of an inductively coupled plasma processing device, wherein the device has a vacuum processing chamber, a radio frequency power source and a bias power source, the radio frequency power source couples a radio frequency signal into the vacuum processing chamber through an inductively coupled coil, the bias power source applies a bias signal to a base inside the vacuum processing chamber through a radio frequency matching network, and the base is used to support the substrate to be processed; the method includes: obtaining a control command; the bias power source executes the control command to generate the bias signal; wherein, The bias signal is a pulse voltage, which is used to ignite a plasma together with the radio frequency signal; the time elapsed from turning on the radio frequency power source to generating the plasma in the vacuum processing chamber is T, the turning on time of the bias power source is not later than the turning on time of the radio frequency power source, and the turn on duration is not less than T; the pulse width of the pulse voltage is 0.1T-10T. The method as described in claim 1, wherein the bias power source executes the control command to generate the bias signal, comprising: executing the control command, turning on the bias power source to generate the bias signal; turning on the bias power source for a set time, turning on the radio frequency power source to generate the radio frequency signal. The method according to claim 2, wherein the setting time is less than 200ms. The method according to claim 1, wherein the duty cycle of the pulse voltage is set to be lower than 10%. The method according to claim 1, wherein the bias power for setting the pulse voltage is less than 50 watts. The method according to any one of claim 1 to claim 5, wherein the inductively coupled coil is a combination of a plurality of single-turn coils or a plurality of half-turn coils. An inductively coupled plasma processing device, which includes: a vacuum processing chamber, a radio frequency power source, and a bias power source; the radio frequency power source couples a radio frequency signal into the vacuum processing chamber through an inductively coupled coil, and the bias power source applies a bias signal to a base inside the vacuum processing chamber through a radio frequency matching network, and the base is used to support the substrate to be processed; it also includes a controller electrically connected to the bias power source, and the controller generates a control command; after the bias power source obtains the control command, The bias power source is used to execute the control command, and turn on the bias power source to generate the bias signal; the bias signal is a pulse voltage, which is used to ignite a plasma together with the radio frequency signal; when the time from turning on the radio frequency power source to generating the plasma in the vacuum processing chamber is T, the turn on time of the bias power source is not later than the turn on time of the radio frequency power source, and the turn on duration is not less than T; the pulse width of the pulse voltage is 0.1T-10T. The device according to claim 7, wherein the inductively coupled coil is a combination of multiple single-turn coils or a combination of multiple half-turn coils.

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