JPH07263181A - Plasma measuring device - Google Patents

Abstract

PURPOSE:To make a high vacuum exhaust device unnecessary and apply to a mass production facility by producing a detecting element of energy of plasma particles and their intake amount by using LSI hyper-fine machining technology. CONSTITUTION:A g-line stepper and dry etching technology as LSI hyper-fine machining technology are applied to film forming processes of a first electrode 11 having the same potential as a material under working, a second electrode 12 for selecting energy of a charged particle in reactive particles, and a third electrode 13 for detecting intake amount of reactive particles, to film forming processes of layer-between-electrodes insulating films 14a, 14b, and to a process for forming a detecting element 16 by perforating a detecting element hole 15. The dimension (d) of the detecting element 16 produced becomes sufficiently small compared with a mean free path of a plasma reactive particle, and generation of collision of reactive particles in a high vacuum exhaust device can be prevented. Use of the high vacuum exhaust device is unnecessary, remodeling of the conventional plasma reaction device is also unnecessary, and a plasma measuring device capable of applying to a mass production facility is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma measuring apparatus for measuring the energy distribution and the influx flux of high-speed reactive particles incident on a workpiece from plasma in a reactive processing apparatus utilizing plasma.

[0002]

2. Description of the Related Art Plasma technology is used in LSI manufacturing.
It is widely used for fine etching and CVD thin film fabrication. In particular, in recent years, high-density low-pressure plasma such as electron cyclotron resonance or magnetron has been developed,
Finer etching processing or high quality thin film formation has become possible. However, in such a high-density plasma, the magnetic field in the device is not uniform, and the strength and / or direction differs depending on the place. This non-uniformity of the magnetic field makes the plasma potential and / or density spatially non-uniform, causing non-uniformity of the processing speed and / or causing element deterioration due to electrification of the workpiece, which is a major problem. There is.

As a method for solving such a problem, the spatial distribution of the energy and / or the incident amount of the reactive particles such as ions incident on the workpiece in the reactor is changed under various plasma conditions and / or the apparatus structure. A technique for measuring the plasma conditions and finding a plasma condition and / or a device structure in which the non-uniformity of the spatial distribution is reduced or lower is being studied and developed.

FIG. 6 shows a conventional plasma measuring apparatus installed in a plasma reaction apparatus used for manufacturing an LSI device or the like. Here, the plasma reactor is the plasma reactor 3
1, an upper ground electrode 32 provided in the plasma reaction container 31, a lower electrode 33 facing the upper electrode 32 and mounting a workpiece, and an upper electrode 32.
And a high frequency power supply 34 for applying a high frequency voltage for generating plasma, which is connected to the lower electrode 33 via a capacitor 34a. In such a plasma reaction apparatus, in the conventional plasma measurement apparatus for performing the conventional plasma measurement method that is usually performed,
Lower electrode 3 on which the work piece is placed, as shown in FIG.
3 is provided with an orifice 41 for extracting particles, and a mesh electrode 42, which is connected to a variable power source 46 to detect the energy distribution of charged particles at the lower rear portion of the orifice 41, and whose potential can be arbitrarily set, and an incident amount are detected. For this purpose, a measuring tube 40 composed of a charged particle detection electrode 44 (ion collector electrode) connected to a minute ammeter 43 is installed, and the pressure in the plasma reactor during plasma processing (for example, usually several mTorr to several Torr). Even when the (high vacuum) is relatively high, the average target process of the reactive particles in the measuring tube 40 is lengthened, and the pressure in the measuring tube 40 is set to a high vacuum in order to sufficiently prevent the reactive particles from colliding with each other. A high-vacuum exhaust device 45 is provided below the ion collector electrode 44 of the measuring tube.

[0005]

However, in the conventional plasma measuring apparatus, the mesh electrode 42 and the orifice 4 are used.
Since No. 1 was manufactured by the metal processing technology, it had a size larger than about several hundreds of microns due to processing accuracy and mechanical strength limitations. On the other hand, the pressure inside the container 31 of the plasma reactor may be set to a maximum of about several Torr, and the mean free path of plasma (reactive) particles may be several hundreds of microns or less. Therefore, in order to accurately measure the energy and the inflow amount of the reactive particles entering the orifice, the measuring tube 40 is provided so that the reactive particles do not collide with other reactive particles in the measuring tube 40. With the high vacuum exhaust device 45,
It was necessary to make it below orr. For this reason, the above-described conventional plasma measuring device has a problem that it requires a major modification of the plasma reaction device and is difficult to apply to a mass production device.

For example, in a normal reactive plasma, the amount of incident ions is about 10 μA / cm ² . Therefore, in order to perform accurate measurement with the conventional plasma measuring apparatus, a detection unit of about 1 cm ² or more is usually required. With this conventional device, 1 cm above the ion collector electrode
^{About 2} insulating rings are attached and a mesh electrode is provided on it. In addition, a similar insulating ring and first
A mesh electrode is provided. In this case, in consideration of the strength and bending of the mesh electrode, the distance between the electrodes needs to be usually about 1 mm or more. However, in this case, several To
At the pressure of rr, there is a problem that the ions and neutral particles collide in the detection unit and the energy incident amount cannot be obtained accurately. Therefore, in order to obtain an accurate value with almost no collision even at a pressure of several Torr, the size of the element portion is at least about one-third of the mean free path, that is, 100.
However, it is difficult to reduce the size of the detecting element to about 100 to 200 μm or less by the conventional mechanical metal working technique as described above.

An object of the present invention is to solve the above-mentioned problems of the prior art and to manufacture a detection element for detecting the energy and the inflow amount of plasma particles (reactive particles) by an LSI microfabrication technique, thereby making a plasma Even at the pressure inside the plasma reactor of the processing apparatus, it is possible to prevent the collision of reactive plasma particles with each other and to accurately measure the energy and inflow amount of plasma particles, thus eliminating the need for a high vacuum exhaust device. It is an object of the present invention to provide a plasma measuring device which can be applied to a mass production device without requiring a major modification of a conventional plasma reaction device.

[0008]

In order to achieve the above object, the present invention provides a plasma measuring device for measuring the energy and inflow amount of reactive particles incident on a material to be processed from plasma in a plasma reaction device, A detection electrode for detecting the energy and inflow amount of the reactive particles has a predetermined opening for forming a detection element hole, and a first electrode having the same potential as the workpiece, and a first electrode of the first electrode. A first electrode or a plurality of second electrodes, each having an opening of substantially the same shape corresponding to the opening, for selecting energy of charged particles in the reactive particles; and a third electrode for detecting an inflow amount of the reactive charged particles An electrode and an inter-electrode interlayer insulating film sandwiched between the respective electrodes, at least a portion corresponding to the opening of the first electrode being opened, and the first electrode, the second electrode and the respective electrodes The interlayer insulating film is an LSI There is provided to be stacked using the processing technology.

Here, in the detection element, a third electrode made of a conductive electrode material is formed directly on a conductive material substrate or on a non-conductive material substrate, and then an interlayer insulating film is formed and a second electrode is formed. The film formation of the electrodes is repeated at least once, and then, after forming the interlayer insulating film and the film formation of the first electrode, a photoresist is applied thereon, exposed and developed, and dry etching is performed to form each electrode and the interlayer. It is preferable that the detection element hole having a predetermined size is formed in the insulating film.

Further, in the above plasma measuring apparatus, the detecting plasma measuring apparatus, wherein the detecting element is
Further, among the reactive particles, which are fine holes provided in the third electrode and under the third electrode, high-speed reactive neutral particles that pass through the fine holes provided in the third electrode And a substance that reacts with.

Here, the area of the fine holes of the third electrode is 1 / the area of the third electrode exposed in the detection element hole.
It is preferably 4 or less, and the side wall of the interlayer insulating film is
It is preferable to recede from the first, second, and third electrode surfaces. Further, it is preferable to have a measuring instrument in which a plurality of the detecting elements are integrated on one chip, and a plurality of measuring instruments in which the plurality of detecting elements are integrated are arranged on one wafer. Is preferred. Furthermore, it is preferable that the dimension of the detection element in the stacking direction is 100 μm or less, and the relationship between the thickness (b) of the interlayer insulating film and the detection element hole diameter (a) is 5b. > A is preferred.

[0012]

According to the plasma measuring apparatus of the present invention, in order to measure the energy and / or the inflow amount of the incident particles from the plasma, the first electrode having the same potential as the workpiece and / or the lower electrode of the plasma reactor is used. , A measuring unit in which a detection element is formed from at least one or more second electrodes for detecting the energy of incident charged particles from plasma and a third electrode for detecting the inflow amount is used by a fine processing technique used in the manufacture of an LSI device. By making it, the size of the measurement part is set to a size without collision of particles inside the measurement part, preferably 100 microns or less even if the size of the measurement part is several Torr. Since it can be made sufficiently smaller than the mean free path of the characteristic (plasma) particles,
The collision of reactive particles can be almost eliminated without providing a special high vacuum exhaust device or major modification of the plasma reactor itself. It is possible to accurately and easily measure the energy and inflow amount of the functional particles.

In the plasma measuring apparatus of the present invention, by using two kinds of second electrodes having different potentials as the second electrode, it is possible to measure the energy and inflow amount of both positive and negative ions and electrons, respectively. Further, it is possible to measure the energy and the inflow rate of the reactive neutral particles at a high speed by providing the third electrode with fine holes and providing the neutral particle reactive substance layer thereunder.

As described above, according to the plasma measuring apparatus of the present invention, the energy and the inflow amount of the reactive particles can be measured accurately and easily, so that the plasma having uniform etching characteristics can be obtained in the mass production apparatus. become able to.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A plasma measuring apparatus according to the present invention will be described in detail with reference to the preferred embodiments shown in the accompanying drawings.

FIG. 1 is a schematic diagram showing the construction of an embodiment of the plasma measuring apparatus of the present invention. As shown in the figure, the plasma measurement device 10 includes a first electrode 11 and a second electrode 12,
First and second inter-electrode interlayer insulating films 14a and 1 sandwiched between the third electrode 13 and the first electrode 11 and the second electrode 12 and between the second electrode 12 and the third electrode 13, respectively.
4b and a first of the laminates
A detection element 16 having a detection element hole 15 opened in the electrode 11, the first interlayer insulating film 14a, the second electrode 12 and the second interlayer insulating film 14b; a high frequency source 17 connected to the first electrode 11; A variable power source 18 connected to the two electrodes 12,
It has a minute ammeter 20 connected to the third electrode 13 and a variable power source 19 connected to the minute ammeter 20. Here, the high frequency source 17 and the variable power sources 18 and 19 are grounded.

Here, the first electrode 11 is for reproducing the inflow amount and energy of the reactive particles that actually enter the surface to be processed, and has an opening through which the reactive particles enter. Then, it is set to the same potential as the lower electrode (see FIG. 5 described later) 33 on which the workpiece and / or the detection element 16 is mounted, for example, OV. The second electrode 12 has an opening through which reactive (plasma) particles enter from plasma, is an electrode for detecting the energy of the charged reactive particles, and its potential is arbitrarily set to detect the energy distribution. It is connected to a variable power source 18 so that it can be set. In the illustrated example,
Of the reactive particles, the second electrode 12 passes positive ions in order to detect the energy of positive ions (positively charged particles) and prevents negative ions and electrons (negatively charged particles) from passing through. The variable electrode 18 sets a predetermined negative potential.

The third electrode 13 constitutes the bottom of the detection element hole 15 of the detection element 16 and is for detecting the inflow amount of the charged reactive particles. The ammeter 20 is for measuring as a minute current value. Therefore, in the illustrated example, in order to pass all positive ions (positively charged particles), the variable electrode 19 is set to a predetermined negative potential (higher than the potential of the second electrode 12). Between the first electrode 11 and the second electrode 12, and between the second electrode 12 and the third electrode 13, the first and second inter-electrode interlayer insulating films 14a and 14b are inserted, respectively, and have substantially the same shape. It has an opening.

These first electrode 11 and first interlayer insulating film 1
The openings 4a, the second electrode 12, and the second interlayer insulating film 14b constitute the inner wall surface of the detection element hole 15 of the detection element 16, for example, the inner wall surface of the circular hole, and the third electrode 13 is the detection element hole 1
5 forms the bottom surface, for example, a circular bottom surface. Here, the shape of the detection element hole 15 is not particularly limited, and may be a square, a slit, an ellipse, an irregular shape, or the like in addition to a circle. In the present invention, such a first electrode 1
1, a first interlayer insulating film 14a, a second electrode 12, a second interlayer insulating film 14b, and a third electrode 13 are stacked, and a detection element hole 15 is punched in this stacked body to form a detection element. As a technique, a fine processing technique used for manufacturing an LSI device is used. The conductive microfabrication technique used in the present invention includes the step of forming the first electrode 11, the step of forming the first interlayer insulating film 14a, the step of forming the second electrode 12, and the second step.
The step of forming the interlayer insulating film 14b, the step of forming the third electrode 13, the step of coating / photosensitizing / developing a photoresist for punching / forming the detection element holes 15, and the electrodes 11, 12, 13
And the step of etching the interlayer insulating films 14a and 14b. In particular, by applying g-line stepper and dry etching technology as LSI microfabrication technology,
It is possible to create the detection element 16 having a detection element hole 15 diameter of 1 μm or less.

In the present invention, by introducing the LSI microfabrication technique into the production of the plasma detection element of the plasma measuring apparatus, the dimension of the detection element, that is, the dimension d in the stacking direction shown in FIG. 1 and FIG. In the embodiment shown in FIGS. 3 and 4, the material layer 26 is included for the first time to be equal to or less than the mean free process of the plasma particles in the atmosphere in the plasma reactor (pressure in the plasma reactor: about several Torr maximum). However, in the present invention, the detection element 16 (22, 23, 2) is further added.
The dimension d of 4) is preferably 100 μm or less. The reason for this is that the device dimension d is set to be 1/2 of the mean free path of particles.
Since it can be set to 1/3 or less, collision of particles in the detection element hole 15 such as the detection element 16 can be almost eliminated, and more accurate measurement can be performed.

The first, second and third electrodes 11, 1 of the present invention
The electrode material applied to 2 and 13 is not particularly limited as long as it is conductive, but any material is preferable because it is easy to form a film and is processed. For example, polysilicon (pol) is typically used.
y-Si), Al, Cr, Cu or composite combinations thereof are commonly used. The interlayer insulating film 14 (14a, 14b) used in the present invention is not particularly limited as long as it can have insulation between electrodes, but, for example, typically, a silicon oxide film, a silicon nitride film, or a polyimide. Membranes are used. As the variable power sources 18 and 19, a voltage necessary to detect the energy and the inflow amount of the charged reactive particles to the second electrode 12 and the third electrode 13, for example, −50.
Any voltage may be applied as long as it can apply a voltage in any range of 0 V to 500 V. Also,
The power sources 18 and 19 may be constant voltage sources when the charged particles to be detected are previously determined. The microammeter 20 is not particularly limited as long as it can measure a microcurrent of the order of μA or 10 μA.

The detection element 16 of the plasma measuring apparatus 10 shown in FIG. 1 is composed of one electrode, which is set to a predetermined negative potential for measuring only positive ions as reactive particles, as the second electrode 12. However, the present invention is not limited to this, and two or more second electrodes may be used. When measuring both positive and negative ions or positive ions and electrons, two second electrodes 12a and 12b for positively charged particles and for negatively charged particles are required like the detection element 22 of the plasma measuring device 21 shown in FIG. Is.
Of course, the interlayer insulating film 14c is interposed between the two second electrodes 12a and 12b. These two second electrodes 12a
And 12b are variable power supplies 18a and 18b, respectively.
Connected to. The other components are the same as those of the plasma measurement device shown in FIG.

By the way, these variable power sources 18a and 1
8b is configured to be able to set voltages of different polarities. For example, in the illustrated example, the upper second electrode 12a is used to set a predetermined positive potential by the variable electrode 18a in order to repel positive ions (positively charged particles) and prevent them from passing through. Lower second electrode 12
b is used to set a predetermined negative potential by the variable electrode 18b in order to repel negative ions and electrons (negatively charged particles) and prevent them from passing through. At this time, the electric potential of the third electrode 13 may be appropriately set according to the type of the reactive particles to be measured including the polarity.

In plasma processing, charged particles such as positive and negative ions and electrons, as well as high-speed neutral particles generated by the resonance charge exchange reaction, may have a great influence on the processing reaction.
The detection element of the plasma measurement device for measuring the high-speed reactive neutral particles is the detection element hole 1 in the detection element 22 of the plasma measurement device shown in FIG. 2 as shown in FIGS.
5, a fine hole 25 is formed substantially in the center of the third electrode 13, and a high-speed neutral particle detection layer made of a substance that sputters and / or reacts with the high-speed reactive neutral particles is formed below the third electrode 13. 26 is formed, and the potentials of the two second electrodes 12a and 12b are set so as to repel both positive and negative charged particles. With this configuration, in the detection elements 23 and 24,
Only the high speed neutral particles pass through the fine holes 25 provided in the third electrode 13, and the high speed neutral particles cause the high speed neutral particle detection substance layer 26 provided below the third electrode 13 to easily sputter and / or Alternatively, they are reacted to form the hole 26a. By measuring the size of the hole 26a thus formed, the inflow amount of the fast-reactive neutral particles can be measured.

A material layer 26 formed below the third electrode 13
Is not particularly limited as long as it is a substance that easily sputters and / or reacts with high-speed neutral particles, and may be any substance. For example, for plasma when etching a silicon oxide film, the substance 26 is It is preferable to use a silicon oxide film. Further, a variable voltage source may be connected to the third electrode 13 so that the third electrode 13 also has the function of the second electrode 12. The fine holes 25 of the third electrode 13 may be made small enough not to cause a decrease in detection accuracy of the third electrode 13,
For example, when the detection element hole 15 is a circular hole, usually the third electrode 1
It is preferable that the area is ¼ or less of the area of the diameter of 3.

In a plasma having a high pressure of 1 Torr or more, ions collide with gas molecules in the plasma sheath, and a large number of particles are obliquely incident. The obliquely incident particles and the particles whose tracks are bent by the repulsive force of each electrode collide with the side wall of the interlayer insulating film 14 (14a, 14b, 14c). A part of the particles that collide with the side wall may be reflected by the side wall and reach the third electrode 13, which may cause a measurement error. In this case, therefore, it is preferable to have a structure in which the interlayer insulating film 14 is made to recede as shown in FIG. 4 by isotropic etching. In the embodiment shown in FIG. 4, the third electrode 1
3 has the fine holes 25, the material layer 26 is also isotropically etched to form the holes 27 in advance.
It is necessary to measure the hole 27 before measuring the high speed neutral particles. The receding of the interlayer insulating film 14 due to the isotropic etching is shown in FIGS. 1 and 2. Of course, it may be applied to the embodiment.

FIG. 5 shows an embodiment in which the plasma measuring apparatus of the present invention using the above-mentioned plasma detecting element is applied to a plasma reaction apparatus for manufacturing an LSI device. In the same figure, the plasma reaction device 30 is similar to the plasma reaction device shown in FIG. 10, and has a plasma reaction container 31, an upper earth electrode 32 provided in the plasma reaction container 31, and a surface facing the upper electrode 32. A lower electrode 33 for mounting the workpiece, an upper electrode 32, and a lower electrode 33 connected to the lower electrode 33 via a capacitor 34a, and a high-frequency power source 34 for applying a high-frequency voltage for generating plasma. Composed of.

The plasma detection element used in the plasma measuring device 35 shown in FIG. 5 has two second electrodes 12a and 12b shown in FIGS. 2 to 4, but preferably, these detection elements are used. A large number of 22 (23 or 24) are integrated on one chip and one measuring instrument (measurement chip)
27, and the measuring chip 27 is connected to the measuring lead wire 2
8 and a bundle of these lead wires 28 into a reaction container 31.
A side wall window of the existing device is used as a lead wire outlet, and a protective cylinder (sheath) 29 is airtightly attached to the lead wire outlet, and external variable power sources 18a, 18b,
19, by connecting to the ammeter 20, the high frequency source 34, the condenser 34a, etc., the plasma measuring device 35 is configured without modifying the plasma reaction device 30.

In the plasma measuring device of the present invention, FIG.
The reason why the integrated measuring elements are integrated into one chip and the power source and the ammeter provided outside the reaction apparatus are connected to this chip is as follows. Usually, the inflow amount of particles entering the measuring element of the conductor is small, and for example, the diameter is 10
The amount of current incident on the circular element of μm is only about 10 ⁻¹¹ A in the reactive plasma used in the manufacture of ordinary LSI devices. Therefore, in order to measure the inflow amount with high accuracy, it is usually preferable to integrate a large number of measuring elements of about 10 ⁶ to form one measuring instrument. By moving the position of the measuring chip 27 in which such a large number of measuring elements are integrated, it is possible to perform measurement at any place on the electrode 33. The lead wire 28 connected to the measuring chip 27 is preferably protected by polyimide or the like to prevent plasma exposure. Alternatively, all of the lead wires 28 may be put in the protective cylinder.

Further, instead of moving the measuring chip 27,
If a plurality of independent integrated measuring instruments 37 are concentrically provided on the wafer 36 like the probe wafer 39 shown in FIG. 6, the radial distribution can be measured efficiently. Here, reference numeral 38 is an extraction electrode of the detection signal of the integrated measuring instrument 37. The arrangement of the measuring instruments 37 is not limited to concentric circles, and various structures such as a column may be selected depending on the structure of the reactor and the purpose.

In the embodiment shown in FIGS. 1 to 4, if the hole diameter a of the detecting element 16 (22 to 24) is too large and / or the thickness b of the interlayer insulating film 14 is too small, the detecting element 16 is too small. In some cases, the potential distribution is formed in the radial direction of, and the ion energy selection accuracy is degraded. For example, when using a detector as an ion energy analyzer, a / b
Is large, as shown in FIG. 7, a part of the incident ions is laterally distorted due to the lateral potential distribution and is absorbed by the second electrode 12 and the ion collector electrode (third electrode).
Electrode) 13 is not reached. When the interlayer insulating film thickness b was 4 μm or more with respect to the detection element hole diameter a of 10 μm, the arrival rate to the collector electrode 13 was about 75% or more as shown in FIG. When the thickness b was set to 2 μm, the arrival rate sharply decreased to 50% or less. Ion collector electrode 13
The arrival rate also changes when the potential of 2 and the potential of the second electrode 12 are changed, but in both cases, the arrival rate sharply decreases when the interlayer insulating film thickness b is 2 μm or less. Further, when a / b is large, the effect of the second electrode 12 which functions as an electron repulsion is reduced, and secondary electrons emitted when ions are incident on the ion collector electrode 13 do not repel and escape to the outside of the detection element 16. Measurement error occurs. When the element hole diameter a was 10 μm, this error also sharply increased when the interlayer insulating film thickness b was 2 μm or less. For the above reason, in the present invention, it is preferable to limit the relationship between the detection element hole diameter a and the interlayer insulating film thickness b to 5b> a.

(Example 1) 100 mTorr of HCl plasma was formed by a parallel plate type reactor and measured with a probe wafer 39 having the structure shown in FIG. 6 placed on the lower electrode 33. The detection element has the structure shown in FIG. 1, and each detection element 16 is a detection element hole 1 having a diameter a of 10 μm.
Have 5 The first electrode 11 is connected to the silicon substrate and has the same potential (OV) as the lower electrode. The second electrode 12 has only one layer to repel negative ions and electrons, and is set to −50 V to prevent passage of incident electrons and secondary electrons. The ion collector electrode (third electrode) 13 was set to -10 V in order to pass all positive ions. The film thickness c of each electrode 11, 12, 13 and the interlayer insulating films 14a, 1
The thickness b of 4b was 2 μm and 7 μm, respectively. In the first embodiment, all the positive ions incident on the detection element 16 were detected by the ion collector electrode 13. Further, the ratio a / b of the detection element hole diameter a and the interlayer insulating film b is 1.43, which is so small that the measurement error due to incident electrons or secondary electrons can be ignored. Further, since the lead wire 28 to each of the electrodes 11, 12, and 13 can also utilize the existing plasma reactor side wall window, plasma measurement can be performed without modifying the reactor.

When a permanent magnet having the same size as the lower electrode 33 is provided under the lower electrode 33 to improve the plasma density, iron plates are attached to both poles of the magnet to make the magnetic field uniform. . The effect on the uniformity of the amount of incident ions of the iron plate at this time was investigated by the plasma measuring apparatus of this example, and the reaction apparatus was improved. Without the magnet, a uniform ion injection amount was obtained in the radial direction of the wafer probe 39 as shown in FIG. 9, but the absolute value of the injection amount was 1.
It was about 0 μA / cm ² . When the bar magnet was provided, the plasma density was improved several tens of times at the center of the wafer probe 39, but the non-uniformity in the radius of the wafer probe 39 was large. On the other hand, it was confirmed that when the iron plate was attached to the bar magnet, the plasma density was improved and the uniformity was also high. As described above, according to the present invention, it is possible to easily measure the ion incident amount distribution without modifying the plasma device, and as a result, it is possible to efficiently improve the device and plasma conditions.

[0034]

As described in detail above, according to the present invention,
The size of the detection element that performs plasma measurement is sufficiently smaller than the mean free path of plasma-reactive particles, and reactive particles hardly collide with each other in the detection element.
It is possible to easily and accurately measure the energy and the inflow amount of the reactive particles incident on the workpiece from the plasma without attaching a special high vacuum exhaust device or specially modifying the plasma reactor. Therefore, it is possible to obtain a plasma having spatially uniform etching characteristics in a mass production plasma processing apparatus.

[Brief description of drawings]

FIG. 1 is a schematic diagram including a cross-sectional view of an embodiment in which a detection device of a plasma measuring apparatus according to the present invention has one second electrode.

FIG. 2 is a schematic diagram including a cross-sectional view of an embodiment in which there are two second electrodes of the detection element of the plasma measurement device according to the present invention.

FIG. 3 is a schematic cross-sectional view of another embodiment of a detection element having a high-speed neutral particle detection unit via a fine hole below a third electrode of the plasma measurement device according to the present invention.

FIG. 4 is a schematic cross-sectional view of another embodiment of the detection element in which the side wall of the interlayer insulating film of the plasma measuring device according to the present invention is receded from the electrode.

FIG. 5 is a schematic diagram of an embodiment in which an embodiment of a measuring chip in which a detection element of the plasma measuring device according to the present invention is integrated is attached to a plasma reaction device.

FIG. 6 is a top view of an embodiment of the wafer probe in which the measuring unit of the plasma measuring apparatus according to the present invention is concentrically arranged on the wafer.

FIG. 7 is a schematic diagram showing a detection error due to a bending of an incident ion in a lateral direction inside a detection element when an interlayer insulating film b of a plasma measuring apparatus according to the present invention is ⅕ of a detection element hole diameter a. is there.

FIG. 8 is a diagram showing the arrival rate of incident ions to a collector electrode when the ratio b / a between the interlayer insulating film and the detection element hole diameter of the plasma measurement apparatus according to the present invention is changed.

FIG. 9 is a graph showing the spatial distribution of the plasma density ratio measured in Example 1 of the present invention.

FIG. 10 is a schematic view showing a conventional plasma measuring device.

[Explanation of symbols]

 10, 21, 35 Plasma measuring device 11 First electrode 12, 12a, 12b Second electrode 13 Third electrode 14, 14a, 14b, 14c Interlayer insulating film 15 Detection element hole 16, 22, 23, 24 Detection element 17, 34 High-frequency source 18, 18a, 18b, 19, 46 Variable power source 20, 43 Ammeter 25 Micropore of the third electrode 26 High-speed neutral particle detection substance layer 26a Hole 27 Measuring chip 28 Measuring lead wire 29 Lead wire outlet Protective cylinder (sheath) 30 Plasma reaction device 31 Plasma reaction vessel 32 Upper ground (ground) electrode 33 Lower electrode 36 Wafer 37 Integrated measuring instrument 38 Extraction electrode 39 Probe wafer 40 Measuring tube 41 Orifice 42 Mesh electrode 44 Charged particle detection electrode 45 High Vacuum exhaust device

Claims (9)

[Claims] 1. A plasma measuring device for measuring the energy and inflow amount of reactive particles incident on a material to be processed from plasma in a plasma reaction device, wherein a detection element for detecting the energy and inflow amount of said reactive particles is provided. A first electrode having a predetermined opening for forming a detection element hole and having the same potential as the workpiece, and an opening of substantially the same shape corresponding to the opening of the first electrode are provided, and the reactivity is provided. One or more second electrodes for selecting the energy of the charged particles in the particles, a third electrode for detecting the inflow amount of the reactive charged particles, and a portion corresponding to the opening of the first electrode are at least An inter-electrode interlayer insulating film that is opened and sandwiched between the electrodes, and the first electrode, the second electrode, and the inter-electrode interlayer insulating film are laminated and formed using an LSI microfabrication technique. Characterized by Zuma measuring device. 2. The detection element comprises forming a third electrode made of a conductive electrode material directly on a conductive material substrate or on a non-conductive material substrate, and then forming an interlayer insulating film and a second electrode. Film formation is repeated at least once, and then an interlayer insulating film is formed and a first electrode is formed, and then photoresist is applied, exposed, and developed, and dry etching is performed to form each electrode and interlayer insulating film. The plasma measurement device according to claim 1, wherein the detection element hole having a predetermined size is formed in the film. 3. The plasma measuring device according to claim 1, wherein the detection element is formed under the fine holes further provided in the third electrode and under the third electrode, and the reaction is performed. A plasma measuring apparatus, characterized in that it has a substance that reacts with high-speed reactive neutral particles that have passed through the fine holes provided in the third electrode among the reactive particles. 4. The plasma measuring device according to claim 3, wherein the area of the fine holes of the third electrode is not more than ¼ of the area of the third electrode exposed in the detection element hole. 5. The plasma measuring apparatus according to claim 1, wherein the side wall of the interlayer insulating film is set back from each of the first, second and third electrode surfaces. 6. The plasma measuring device according to claim 1, further comprising a measuring device in which a plurality of the detecting elements are integrated on one chip. 7. The plasma measuring apparatus according to claim 6, wherein a plurality of measuring devices each having the plurality of detecting elements integrated therein are arranged on one wafer. 8. The dimension of the detection element in the stacking direction is 100 μm.
The plasma measuring device according to any one of claims 1 to 7, which has a size of m or less. 9. The relationship between the thickness (b) of the interlayer insulating film and the detection element hole diameter (a) is 5b> a.
The plasma measuring device according to any one of to 8.