JP2011210715A - Ion current density measuring method, ion current density measuring device, plasma treating device, recording medium, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ion current density measuring method and a device for measuring ion current density indicating the amount of ion irradiation to a treated article in plasma treatment, along with plasma density and an electron temperature using a probe measuring instrument without depending on an ion current measuring instrument.SOLUTION: A plasma treating method and the device include obtaining plasma density n in a vacuum chamber and the electron temperature Te by an electrostatic probe method, computing ion current density J indicating the amount of ion irradiation to the treated article on the basis of the obtained plasma density n and plasma potential Te using J=nq[√(k×Te/M)]exp(-1/2)(wherein q is the amount of ion charge, k is a Boltzmann's constant, and M is ion mass), and controlling a plasma generating device to adjust plasma density so that the computed ion current density heads toward the ion current density indicating the amount of ion irradiation for carrying out target treatment to the treated article. A program for carrying out the method, and a recording medium recording the program are also provided.

Description

  In the present invention, when performing processing such as film formation, ion implantation, etching, and surface cleaning processing on an article to be processed using plasma, the ion irradiation dose to the article to be processed The present invention relates to a method and apparatus for measuring ion current density, and further to a plasma processing apparatus, and further relates to a program used to implement the method and a recording medium on which the program is recorded.

  Plasma processing such as film formation (film formation), ion implantation, etching, surface cleaning processing, etc., in order to perform desired processing, plasma parameters such as plasma density and electron temperature, and processing target It is important to control the irradiation amount of ions on the article, and in order to do so, monitoring of these is indispensable.

In general, there are an optical method and an electrostatic probe method for measuring plasma density and electron temperature, but the latter method is considered simpler when measuring the total ion density.
FIG. 3 shows an example in which the plasma parameter is measured using the single probe method which is one of electrostatic probe methods in the plasma processing apparatus A1.

  A filament power supply 4 is connected to the filament 3 installed in the vacuum chamber 1, and when the filament 3 is heated to a high temperature by passing a current through the filament 3 with the power supply (in this example, an output variable power supply) 4, the filament 3 The thermoelectrons emitted from the surface of the filament 3 are applied between the one end of the filament 3 and the chamber 1 so that the one end of the filament 3 is at a negative potential. Accelerated.

  At this time, when a gas, for example, argon gas, is introduced from the gas supply device (not shown) into the chamber 1 while the chamber 1 is exhausted and reduced to a plasma generation pressure by an exhaust device (not shown), the accelerated thermoelectrons are converted into the gas. The plasma 2 is formed by electron impact ionization. The filament 3, the filament power supply 4, the discharge power supply 5, etc. constitute a plasma generation device P.

  When a negative voltage is applied from a bias power source 10 to a pre-arranged article to be processed in the chamber 1, for example, a substrate S whose surface is to be cleaned with argon gas ions, argon in the plasma 2 The ions are accelerated and irradiated toward the substrate S, and the surface of the substrate S is cleaned.

  At this time, the degree to which the surface is cleaned is proportional to the amount of argon ion irradiation, and also depends on the energy of argon ions. The argon ion energy can be controlled and monitored by the voltage of the bias power source 10, but the argon ion irradiation amount needs to be separately monitored.

  In the example shown in FIG. 3, a single probe measuring instrument 8 is installed in the chamber 1, whereby the plasma density and the electron temperature of the plasma 2 that are plasma parameters can be measured.

  The single probe measuring instrument 8 has a tip (probe portion) 81 formed of a conductive material such as metal, and can apply a voltage to the tip probe 81 from an output variable power source 82, and is widely known per se. Is.

  In measuring the plasma parameters by the single probe measuring instrument 8, a voltage is applied from the power source 82 to the tip probe 81, and the current flowing through the probe 81 at this time is measured by an ammeter 83.

Since it is already known per se, detailed description is omitted, but the plasma density, electron temperature, plasma potential, etc. can be obtained from the voltage-current characteristics obtained at this time.
The measurement of plasma parameters using a probe measuring instrument is described in, for example, “Appendix 1. Probe Measurement Method” of “Latest Plasma Generation Technology” published by IPC Corporation on August 5, 1991 and edited by Yoshinobu Kawai. .

  The monitoring of the amount of ions irradiated on the substrate S seems to be achieved by measuring the current flowing through the substrate S, that is, the current flowing through the bias power supply 10, but actually, secondary electrons from the surface of the substrate S Accurate measurement of the current flowing through the power source 10 is not possible due to changes in the secondary electron emission coefficient due to changes in the substrate surface state accompanying the progress of the substrate surface treatment.

  Therefore, for monitoring the amount of ions irradiated on the substrate S, a current measuring instrument having a structure for suppressing secondary electron emission is required. As a typical current measuring instrument, a suppressor electrode is arranged in front of an ion measuring electrode, and a negative voltage is applied to the ion measuring electrode, whereby secondary electrons emitted from the ion measuring electrode are ion measured again. The thing which can measure an exact ion current by pushing back to an electrode can be mentioned.

  In this way, in addition to the measurement of plasma density and electron temperature, which are plasma parameters, both the probe instrument and the ion current instrument are necessary to accurately measure the ion dose to the article to be processed. .

August 5, 1991, published by IPC, edited by Yoshinobu Kawai, "Latest Plasma Generation Technology", "Appendix 1. Probe Measurement Method"

  However, in order to install both of them in the chamber 1, an installation space for that purpose is required, the chamber size is increased accordingly, the installation area of the plasma processing apparatus is increased, and the plasma processing apparatus is expensive.

  Accordingly, the present invention provides a plasma processing apparatus for generating plasma in a vacuum chamber and performing an intended processing on the article to be processed disposed in the vacuum chamber under the plasma. The ion current density that indicates the amount of ion irradiation can be measured together with the plasma density and electron temperature using a probe measuring instrument without relying on the ion current measuring instrument. A first problem is to provide an ion current density measurement method that can be measured at a low cost while the ion current density can be measured.

  The present invention also provides an article to be processed in plasma processing in which a plasma is generated in a vacuum chamber using a plasma generating apparatus, and an object to be processed disposed in the vacuum chamber is subjected to a target process under the plasma. The ion current density that indicates the amount of ion irradiation can be measured together with the plasma density and electron temperature using a probe measuring instrument without relying on the ion current measuring instrument. A second object is to provide an inexpensive ion current density measuring apparatus that is simplified and capable of measuring ion current density.

  Furthermore, the present invention is a plasma processing apparatus for generating a plasma in a vacuum chamber using a plasma generating apparatus, and subjecting an object to be processed disposed in the vacuum chamber to a target process under the plasma, The ion current density, which indicates the amount of ion irradiation to the article to be processed in plasma processing, can be measured together with the plasma density and electron temperature using a probe measuring instrument without relying on the ion current measuring instrument. A third problem is to provide a plasma processing apparatus that can be measured at a low cost without increasing its size while measuring the ion current density together with the temperature measurement.

  Furthermore, the present invention provides a computer-readable recording medium and a program for recording a program for causing a computer to execute at least a part of the procedure for carrying out the ion current density measuring method according to the present invention. Let it be 5 issues.

In order to solve the first problem, the present invention provides:
The amount of ion irradiation to the article to be processed in the plasma processing in which plasma is generated in the vacuum chamber using the plasma generation apparatus, and the object to be processed disposed in the vacuum chamber is subjected to a target treatment under the plasma. Is a method of measuring the ion current density indicating
Obtaining a plasma density n and an electron temperature Te in the vacuum chamber by an electrostatic probe method using a probe measuring instrument;
Based on the obtained plasma density n and electron temperature Te, the ion current density J indicating the ion irradiation amount to the article to be processed
And calculation using the formula J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ionic charge, k is the Boltzmann constant, and M is the ion mass). An ion current density measurement method is provided.

In order to solve the second problem, the present invention
The amount of ion irradiation to the article to be processed in the plasma processing in which plasma is generated in the vacuum chamber using the plasma generation apparatus, and the object to be processed disposed in the vacuum chamber is subjected to a target treatment under the plasma. Is a device for measuring the ion current density indicating
A probe measuring instrument for determining the plasma density n and the electron temperature Te in the vacuum chamber by an electrostatic probe method;
The plasma density n and electron temperature Te obtained using the probe measuring instrument can be inputted, and the ion irradiation amount to the article to be processed is shown based on the inputted plasma density n and electron temperature Te. Ion current density J
Ion current density calculated using the formula J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ionic charge, k is the Boltzmann constant, and M is the ion mass). An ion current density measuring device including a calculation unit is provided.

The ion current density calculator may include a data input unit for inputting the plasma density n and the electron temperature Te obtained using the probe measuring instrument.
In any case, in the ion current measuring method and apparatus according to the present invention, the electrostatic probe method can be an electrostatic probe method selected from a single probe method, a double probe method, and a triple probe method.

  In the ion current density measuring apparatus according to the present invention, when obtaining the plasma density n and the electron temperature Te in the vacuum chamber obtained using the probe measuring instrument, the user performed this appropriately using a computer or the like. The ion current density may be calculated by inputting the plasma density n and the electron temperature Te into the ion current density calculation unit.

However, a measurement unit for the plasma density n and the electron temperature Te is provided, and the measurement unit can determine the plasma density n and the electron temperature Te in the vacuum chamber using the probe measuring instrument when measuring the ion current density. Good.
Then, the ion current density calculation unit calculates the ion current density J indicating the ion irradiation amount to the article to be processed based on the plasma density n and the electron temperature Te thus obtained, from the formula J = nq [√ (k · Te / M)] · exp (−½) may be used for calculation.

  In any case, the ion current density calculation unit or the plasma density n and electron temperature Te measurement unit may be provided exclusively for the ion current density measurement device according to the present invention. For example, an external computer may be used. It may be used. A computer dedicated to the ion current density measuring device can also be used.

  According to the ion current density measuring method and apparatus according to the present invention, the ion current density indicating the ion irradiation amount to the article to be processed can be measured by using a probe measuring instrument without relying on the ion current measuring instrument. They can be measured together with the temperature, and the ion current density can be measured together with the measurement of the plasma density and the electron temperature.

In order to solve the third problem, the present invention
A plasma processing apparatus that generates a plasma in a vacuum chamber using a plasma generation apparatus and performs an intended process on the article to be processed disposed in the vacuum chamber under the plasma. A plasma processing apparatus including a current density measuring apparatus is provided.

  In the plasma processing apparatus according to the present invention, the ion current density indicating the ion irradiation amount to the article to be processed in the plasma processing can be obtained by using the probe measuring instrument without relying on the ion current measuring instrument. It can be measured at the same time, and it can be provided at a lower cost without increasing the size of the ion current density while measuring the plasma density and the electron temperature.

  In the plasma processing apparatus according to the present invention, the plasma is such that the ion current density calculated by the ion current density calculating unit is directed to an ion current density indicating an ion irradiation amount for performing a target process on the article to be processed. A control unit for controlling the plasma generating apparatus to adjust the density n may be included.

  In any case, in the plasma processing apparatus according to the present invention, the treatment to be performed on the article to be treated under plasma includes film formation on the article to be treated, etching of the article to be treated, One or more treatments selected from ion implantation and cleaning treatment of the surface of the article to be treated can be exemplified.

Moreover, this invention solves the said 4th subject,
A recording medium recording a program for causing a computer to execute at least a part of a procedure for performing an ion current measuring method according to the present invention,
The step of obtaining the density n and electron temperature Te of the plasma in the vacuum chamber by an electrostatic probe method using a probe measuring instrument, and the ion irradiation amount to the article to be processed based on the obtained plasma density n and plasma potential Te Ion current density J indicating
A step of calculating using the equation J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ionic charge, k is the Boltzmann constant, and M is the ion mass). Provided is a computer-readable recording medium on which a program to be executed is recorded.

In order to solve the fifth problem, the present invention is also a program for causing a computer to execute at least a part of a procedure for performing the ion current measurement method according to the present invention,
The step of obtaining the density n and electron temperature Te of the plasma in the vacuum chamber by an electrostatic probe method using a probe measuring instrument, and the ion irradiation amount to the article to be processed based on the obtained plasma density n and plasma potential Te Ion current density J indicating
A step of calculating using the equation J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ionic charge, k is the Boltzmann constant, and M is the ion mass). We also provide a program to make it run.

  The program according to the present invention or the program recorded on the recording medium according to the present invention further includes an ion calculated by the formula J = nq [√ (k · Te / M)] · exp (−1/2). For causing a computer to execute a step of controlling the plasma generation device so as to adjust the plasma density so that the current density is directed toward an ion current density indicating an ion irradiation amount for performing a target process on the article to be processed. May contain a program.

  As described above, according to the present invention, plasma processing is performed in which a plasma is generated in a vacuum chamber using a plasma generation apparatus, and an object to be processed placed in the vacuum chamber is subjected to a target processing under the plasma. In this case, the ion current density indicating the ion irradiation amount to the article to be processed can be measured together with the plasma density and the electron temperature using a probe measuring instrument without relying on the ion current measuring instrument. It is possible to provide an ion current density measuring method that can be measured at a low cost while the ion current density can be measured together with the above measurement.

  Further, according to the present invention, in the plasma processing for generating plasma in the vacuum chamber using the plasma generating apparatus and performing the target processing under the plasma on the processing target disposed in the vacuum chamber, the processing target Ion current density, which indicates the amount of ion irradiation to an article, can be measured together with plasma density and electron temperature using a probe measuring instrument without relying on an ion current measuring instrument. Therefore, it is possible to provide a simplified and inexpensive ion current density measuring apparatus that can measure ion current density.

  Furthermore, according to the present invention, there is provided a plasma processing apparatus for generating a plasma in a vacuum chamber using a plasma generating apparatus, and subjecting an object to be processed disposed in the vacuum chamber to a target process under the plasma. The ion current density indicating the ion irradiation amount to the article to be processed in the plasma processing can be measured together with the plasma density and the electron temperature using the probe measuring instrument without relying on the ion current measuring instrument. It is possible to provide a plasma processing apparatus that can be manufactured at a lower cost without being increased in size while the ion current density can be measured together with the measurement of the electron temperature.

  In addition, according to the present invention, it is also possible to provide a program for causing a computer to execute at least a part of the procedure for carrying out the ion current density measuring method according to the present invention, and a computer-readable recording medium on which the program is recorded.

It is a figure which shows one example of the plasma processing apparatus which concerns on this invention. It is a figure which shows the sheath formed between a to-be-processed article (base material) and plasma. It is a figure which shows the example which is measuring the plasma parameter by a probe measuring device in a plasma processing apparatus.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 shows an example A of a plasma processing apparatus provided with an example B of an ion current density measuring apparatus according to the present invention.
The plasma processing apparatus A shown in FIG. 1 includes the same plasma generating apparatus P and single probe measuring instrument 8 as the plasma generating apparatus P and probe measuring instrument 8 in the plasma processing apparatus A1 shown in FIG. The vacuum chamber 1, the holder 6 of the article S to be processed, and the power source 10 for applying a bias voltage thereto are the same as those of the apparatus A1, and the gas supply apparatus to the chamber 1 and the exhaust apparatus from the chamber 1 are not shown. I have.

  The plasma generator P includes a filament 3, a filament power source 4 with variable output, and a discharge power source 5. A current is passed from the power source 4 to the filament 3 to heat the filament 3 and discharge thermoelectrons from its surface, while discharging. By applying a voltage from the power supply 5, the thermal electrons are accelerated and collided with a decompressed gas (for example, argon gas) in the chamber 1, and the plasma 2 can be formed by electron impact ionization.

  By applying a negative voltage from the bias power source 10 to the article to be processed on the holder 6, for example, the substrate S whose surface is to be cleaned with argon gas ions, the argon ions in the plasma 2 are accelerated and irradiated toward the substrate S. Thus, the surface of the substrate S can be cleaned.

  As described above, the degree to which the surface is cleaned is proportional to the argon ion irradiation amount. Therefore, in the plasma processing apparatus A, the probe measuring device 8 is used to measure the ion current density indicating the ion irradiation amount.

  In the example shown in FIG. 1, a single probe measuring instrument 8 is installed in the chamber 1, whereby the plasma density and the electron temperature of the plasma 2 that are plasma parameters can be measured. The probe measuring instrument 8 operates as instructed by the computer PC via the interface 7.

  The probe measuring instrument 8, the interface 7, the personal computer PC, etc. constitute an ion current density measuring apparatus B.

The computer PC is loaded with the following program from the recording medium M in advance.
The step of obtaining the plasma density n and electron temperature Te in the vacuum chamber by an electrostatic probe method using a probe measuring instrument, and the ion irradiation amount to the article S to be processed based on the obtained plasma density n and plasma potential Te Ion current density J indicating
A step of calculating using the equation J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ion charge amount, k is the Boltzmann constant, and M is the ion mass). It is a program for making it run.

The computer PC further reads the next program from the recording medium M in advance. That is,
The ion current density calculated by the formula J = nq [√ (k · Te / M)] · exp (−1/2) indicates the ion irradiation amount for applying the target treatment to the article to be treated S. This is a program for causing a computer to execute the step of controlling the output of the filament power supply 4 in the plasma generating device P so as to adjust the plasma density so as to go to the ion current density that is predetermined and stored in the computer PC.

  When the single probe measuring instrument 8 is instructed to output a voltage from the personal computer PC via the interface 7, the single probe measuring instrument 8 applies a voltage from the output variable power source 82 to the tip probe 81. To detect. The current-voltage characteristics at this time are input to the computer PC, and the computer PC is known per se from the voltage-current characteristics and is stored in advance in the computer PC from the recording medium M in accordance with the calculation procedure. Electron temperature, plasma potential, etc. can be determined.

Further, the computer PC calculates the ion current density J based on the plasma density n and the electron temperature Te thus obtained,
Calculation is performed using the formula J = nq [√ (k · Te / M)] · exp (−1/2).

  The ion current density J thus obtained is compared with the reference ion current density stored in advance in the computer PC for performing the desired target processing, and the plasma density n obtained using the probe measuring instrument 8 and The output of the filament power supply 4 is adjusted under the instruction of the computer PC so that the ion current density J calculated based on the electron temperature Te is directed to the reference ion current density. When the calculated ion current density is too large, the output of the power source 4 is decreased to lower the plasma density. When the calculated ion current density is too small, the output of the power source 4 is increased to increase the plasma density n. Enlarge.

  Next, the fact that the ion current density can be calculated using the formula J = nq [√ (k · Te / M)] · exp (−1/2) will be described.

In this example, a negative voltage is applied from the power source 10 to the base material S arranged at a position facing the plasma 2. As shown in FIG. 2, the negative voltage is applied between the plasma 2 and the base material S. Thus, the sheath sh is formed. The space charge limited current density J ₁ in the ion sheath region is given by the following Child-Langmuir equation (1).

ここで、ε₀ は真空中の誘電率、ｑはイオンの電荷量、Ｍはイオンの質量、Ｖはシース電圧、ｒはシース幅である。
なお、この例では説明を簡単にするためイオン種は１種類としている。イオン種が複数種類のときについては後述する。

Here, ε ₀ is the dielectric constant in vacuum, q is the charge amount of ions, M is the mass of ions, V is the sheath voltage, and r is the sheath width.
In this example, only one ion species is used to simplify the explanation. The case where there are a plurality of ion species will be described later.

On the other hand, the ion saturation current density at the sheath end J ₂ is given by the following equation (2) from the Bohm condition.

ここでｎはプラズマ密度、ｋはボルツマン定数、Ｔｅは電子温度である。

Here, n is the plasma density, k is the Boltzmann constant, and Te is the electron temperature.

When J ₁ = J ₂ = J, the following equation (3) is obtained from equations (1) and (2).

When it can be regarded as a steady state or a steady state, the following equation (4) is obtained by setting dr / dt = 0 in equation (3).

The ion current density J is expressed by the following equation (5) from the equation (2).

  When cleaning the surface of the base material S, it is difficult to remove only contaminants and thin layers of oxide films by ion irradiation. Therefore, the surface of the base material S including these is usually etched to a certain thickness. become. A sputtering rate of ions to the base material is set to 5, for example. Here, the sputtering rate is defined as the number of atoms constituting the base material on which one ion is sputtered. In order to simplify the description, the base material S is assumed to be composed of only one kind of element.

Assuming that the density of the substrate is ρ _s , the mass of the atoms constituting the substrate is m, and the etching rate is R, the following equation (6) is established using the above equation (5).

  From the equation (6), it can be seen that the etching rate R is proportional to the product of the plasma density n and the electron temperature Te to the power of 0.5. Therefore, for example, if the plasma density and the electron temperature are always measured using the single probe measuring instrument 8 as shown in FIG. 1, the etching rate at the time of measurement can be calculated, and the etching amount can be estimated. Therefore, when a predetermined amount of thickness is etched, even if the etching rate changes, the etching rate at that time can be calculated and etching with an accurate thickness can be performed.

  For some reason, the plasma density becomes high, and the temperature of the substrate S may rise too much as the amount of ion irradiation increases. Even in this case, since the plasma density is constantly measured, Such a problem can be prevented by controlling to lower the density.

  The plasma density and the electron temperature can be monitored not only by the single probe method but also by the double probe method or the triple probe method. In the case of plasma in which the plasma potential fluctuates, there may be an error in the measured value in the single probe method. For example, when the substrate S is etched, the error in the etching amount may increase. In such a case, such a problem can be solved by using the double probe method.

  If the time fluctuation of the plasma is large and the plasma density and electron temperature fluctuate with time, the problem can be solved by always performing instantaneous measurement in a very short time using the triple probe method.

  Even when there are two or more types of substrate constituent elements, it is considered that the same relational expression as equation (6) holds if the mass m of the substrate constituent atoms is converted into the average mass of the constituent atoms of the substrate. The quantity can be monitored.

When there are two or more ion species, the following equation (7) holds instead of equation (6).

In formula (7), the subscript i represents an ionic species. The plasma density n measured by the probe method can be expressed by the following equation (8).

Thus it can not determine the individual n _i from equation (8), it is possible to have measured beforehand by a method such as mass spectrometry. Therefore, it is assumed that the following relational expression (9) is obtained.

Here, from the expressions (8) and (9), the following relational expression (10) is satisfied.

Α _i in equation (9) can be considered as a function of the plasma density n, but can be regarded as constant within a range where the plasma density does not change greatly. Then, by substituting equation (9) into equation (7), the following equation (11) is obtained.

  Therefore, from the equation (11), if the plasma density and the electron temperature are measured in the probe method, the etching amount can be monitored.

  Even when ion implantation is performed on the substrate surface, the implantation rate is considered to be proportional to the ion current density given by Equation (5), so if the plasma density and electron temperature are measured in the probe method, the ion implantation is performed. The amount can be monitored.

For example, assuming that the number of ions implanted per unit time and unit area is the _dose rate R _dose , assuming that there is one kind of ion species, one atomic molecular ion, and all ion implantation, the above formula (5) The following equation (12) is established using

  When forming a film on the substrate surface, if only ions contribute to the film formation, as in the case described above, if the plasma density and electron temperature are measured by the probe method, the film thickness during film formation can be monitored. can do.

  If not only ions but also neutral particles such as radicals are involved in the film formation, the ratio becomes a problem. In this case as well, it is possible to measure the ratio using some measurement method in advance. It is. When the plasma density changes, the ratio may also change, but if the plasma density does not change significantly, the approximate ratio can be considered to be constant. As in the case of the above, if the plasma density and the electron temperature are measured in the probe method, it is possible to monitor the film thickness at the time of film formation.

For example, assuming that there is only one kind of ion species, that is, one atomic molecular ion, all of which become a film, and that other than ions do not contribute to film formation, the film density is ρ _f (mass per unit volume), unit time, If the thickness of the film formed per unit area is _defined as the film formation rate R _depo , the following equation (13) is established using the above equation (5).

The computer PC has a program for calculating at least one of the etching amount R, the _dose rate R _dose , and the film forming rate R _depo using at least one of the equations (11), (12), and (13). May be stored in advance from the recording medium M or the like.
The desired factor obtained by the computer PC can be displayed on the display of the computer PC, or can be printed out by a printer (not shown).

  INDUSTRIAL APPLICABILITY The present invention can be used to measure an ion current density indicating an ion irradiation amount to an object to be processed using a probe measuring instrument in processes such as film formation using plasma, ion implantation, and etching.

A, A1 Plasma treatment apparatus 2 Plasma P Plasma generation apparatus 3 Filament 4 Pilement power supply 5 Discharge power supply 6 Holder S Article to be treated (treated substrate in the illustrated example)
B Ion current density measuring device 7 Interface 8 Probe measuring instrument 81 Tip probe 82 Probe power supply 83 Ammeter PC Personal computer M Recording medium 10 Bias power supply sh Sheath r Sheath width

Claims (12)

The amount of ion irradiation to the article to be processed in the plasma processing in which plasma is generated in the vacuum chamber using the plasma generation apparatus, and the object to be processed disposed in the vacuum chamber is subjected to a target treatment under the plasma. Is a method of measuring the ion current density indicating
Obtaining a plasma density n and an electron temperature Te in the vacuum chamber by an electrostatic probe method using a probe measuring instrument;
Based on the obtained plasma density n and electron temperature Te, the ion current density J indicating the ion irradiation amount to the article to be processed
And calculation using the formula J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ionic charge, k is the Boltzmann constant, and M is the ion mass). An ion current density measuring method characterized by the above.   2. The ion current density measuring method according to claim 1, wherein the electrostatic probe method is an electrostatic probe method selected from a single probe method, a double probe method, and a triple probe method. The amount of ion irradiation to the article to be processed in the plasma processing in which plasma is generated in the vacuum chamber using the plasma generation apparatus, and the object to be processed disposed in the vacuum chamber is subjected to a target treatment under the plasma. Is a device for measuring the ion current density indicating
A probe measuring instrument for determining the plasma density n and the electron temperature Te in the vacuum chamber by an electrostatic probe method;
The plasma density n and electron temperature Te obtained using the probe measuring instrument can be inputted, and the ion irradiation amount to the article to be processed is shown based on the inputted plasma density n and electron temperature Te. Ion current density J
Ion current density calculated using the formula J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ionic charge, k is the Boltzmann constant, and M is the ion mass). An ionic current density measurement apparatus comprising: a calculation unit.   The said probe measuring device is a measuring device for calculating | requiring the plasma density n and the electron temperature Te in the said vacuum chamber by the electrostatic probe method chosen from the single probe method, the double probe method, and the triple probe method. Ion current density measuring device. A plasma density and electron temperature measurement unit is included, and the plasma density and electron temperature measurement unit calculates the plasma density n and the electron temperature Te in the vacuum chamber using the probe measuring instrument when measuring the ion current density. ,
The ion current density calculation unit calculates the ion current density J indicating the ion irradiation amount to the article to be processed based on the plasma density n and the electron temperature Te, using the formula J = nq [√ (k · Te / M)]. The ion current density measuring apparatus according to claim 3 or 4 calculated using exp (-1/2).   A plasma processing apparatus for generating plasma in a vacuum chamber using a plasma generating apparatus and performing a target process on the article to be processed disposed in the vacuum chamber under the plasma, A plasma processing apparatus comprising the ion current density measuring apparatus according to claim 5.   The plasma generation to adjust the plasma density n so that the ion current density calculated by the ion current density calculation unit is directed to an ion current density indicating an ion irradiation amount for performing a target process on the article to be processed. The plasma processing apparatus according to claim 6, further comprising a control unit that controls the apparatus.   The treatment performed on the article to be treated under plasma is selected from film formation on the article to be treated, etching of the article to be treated, ion implantation into the article to be treated, and cleaning treatment of the surface of the article to be treated. The plasma processing apparatus according to claim 6, wherein the plasma processing apparatus is one or more processes. A computer-readable recording medium storing a program for causing a computer to execute at least a part of a procedure for performing the ion current measuring method according to claim 1 or 2.
The step of obtaining the density n and electron temperature Te of the plasma in the vacuum chamber by an electrostatic probe method using a probe measuring instrument, and the ion irradiation amount to the article to be processed based on the obtained plasma density n and plasma potential Te Ion current density J indicating
A step of calculating using the equation J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ionic charge, k is the Boltzmann constant, and M is the ion mass). A computer-readable recording medium on which a program to be executed is recorded.   Further, the plasma generation apparatus is controlled to adjust the plasma density so that the ion current density calculated by the above formula is directed to an ion current density indicating an ion irradiation amount for performing a target process on the article to be processed. The recording medium according to claim 9, wherein a program for causing a computer to execute the step of performing is recorded. A program for causing a computer to execute at least a part of a procedure for performing the ion current measurement method according to claim 1,
The step of obtaining the density n and electron temperature Te of the plasma in the vacuum chamber by an electrostatic probe method using a probe measuring instrument, and the ion irradiation amount to the article to be processed based on the obtained plasma density n and plasma potential Te Ion current density J indicating
A step of calculating using the equation J = nq [√ (k · Te / M)] · exp (−1/2) (where q is the ionic charge, k is the Boltzmann constant, and M is the ion mass). A program to make it run.   Further, the plasma generation apparatus is controlled to adjust the plasma density so that the ion current density calculated by the above formula is directed to an ion current density indicating an ion irradiation amount for performing a target process on the article to be processed. The program according to claim 11, comprising a program for causing a computer to execute the step of performing.

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