JP2023120690A - Powder amount measuring apparatus, powder amount measuring method, powder supply device, thermal spraying equipment, substrate polishing device, and three-dimensional printer - Google Patents

Abstract

To provide a powder amount measuring apparatus and a powder amount measuring method, which enable measurement of a supplied powder amount, and provide a powder supply device capable of controlling the supplied powder amount, thermal spraying equipment having the powder supply device like that, a substrate polishing device and a three-dimensional printer.SOLUTION: A powder amount measuring apparatus comprises a charge quantity adjustment part for adjusting the charge quantity of conductive powder supplied from a powder supply source, and a charge quantity measuring part for measuring the charge quantity of the powder, the charge quantity of which is adjusted and which corresponds to a powder amount per unit time, supplied from the powder supply source.SELECTED DRAWING: Figure 1

Description

The present invention relates to a powder quantity measuring device, a powder quantity measuring method, a powder supply device, a thermal spraying device, a substrate polishing device and a three-dimensional printer.

A metal powder spraying apparatus liquefies metal powder such as copper to form a film on a substrate. If the amount of metal powder liquefied per unit time varies, the formed film will have unevenness. Therefore, it is desirable to measure and control the amount of metal powder in situ in real time. The need for measuring and controlling the amount of powder is not limited to metal powder spraying equipment.

JP-A-8-258952

An object of the present invention is to provide a powder amount measuring apparatus and a powder amount measuring method capable of measuring the amount of powder supplied, a powder supply apparatus capable of controlling the amount of powder supplied, and the It is an object of the present invention to provide a thermal spraying apparatus, a substrate polishing apparatus, and a three-dimensional printer having such a powder supply device.

According to one aspect of the invention,
a charge amount adjusting unit that adjusts the charge amount of the conductive powder supplied from the powder supply source;
a charge amount measuring unit that measures the charge amount of the powder whose charge amount has been adjusted and corresponds to the charge amount of the powder supplied from the powder supply source per unit time. A measurement device is provided.

The charge amount adjustment unit may adjust the charge amount of the powder so that the charge amount of the powder falls within a predetermined range.

The predetermined range may correspond to a measurable range of the charge amount measuring section.

The charge amount adjustment unit has a metal member,
A charge amount of the powder may be reduced by contacting the metal member with the powder.

The charge amount adjustment unit has a variable resistance element and a variable capacitance element,
The metal member may be grounded via the variable resistance element and grounded via the variable capacitance element.

A resistance value of the variable resistance element and a capacitance value of the variable capacitance element may be determined according to the powder.

According to one aspect of the present invention, a powder supply source that supplies electrically conductive powder;
a charge amount adjustment unit that adjusts the charge amount of the powder supplied from the powder supply source;
a charge amount measuring unit for measuring the charge amount of the powder whose charge amount has been adjusted;
and a control unit for controlling the amount of powder supplied from the powder supply source per unit time based on the output from the charge amount measuring unit.

The output from the charge amount measuring section may correspond to the amount of powder per unit time supplied from the powder supply source.

The control unit may control the amount of powder supplied from the powder supply source per unit time to be constant based on the output from the charge amount measurement unit.

The powder source is
a ball containing the powder;
a vibrator that vibrates the ball,
The control section may control a vibration amount of the vibrator.

According to one aspect of the present invention, a powder supply device according to any one of claims 7 to 10;
a first electrode provided with a first cavity through which powder from the powder feeder passes;
a second electrode provided with a second cavity through which powder from said first electrode passes;
A thermal spraying apparatus is provided for forming a film on a target by thermally spraying powder with plasma generated between the first electrode and the second electrode.

According to one aspect of the present invention, a powder supply device according to any one of claims 7 to 10;
a liquid supply;
a slurry mixer that mixes the powder from the powder supply device and the liquid from the liquid supply device to generate slurry;
a polishing table;
a nozzle for supplying the generated slurry to the polishing table;
and a substrate holder that holds and rotates a substrate to be polished.

According to one aspect of the present invention, a powder supply device according to any one of claims 7 to 10;
and a laser device for irradiating the powder from the powder supply device with a laser beam.

According to one aspect of the present invention, adjusting the charge amount of powder supplied from a powder supply source;
and measuring the charge amount of the powder whose charge amount is adjusted, the charge amount corresponding to the amount of powder supplied from the powder supply source per unit time.
is provided.

The amount of powder fed can be measured.

1 is a schematic configuration diagram of a powder supply device 100 having a powder amount measuring device 2 according to a first embodiment; FIG. The figure which shows typically the relationship between a sensor output and a powder amount. The schematic block diagram of the thermal spraying apparatus which concerns on 2nd Embodiment. The schematic block diagram of the board|substrate polisher which concerns on 3rd Embodiment. FIG. 11 is a schematic configuration diagram of a three-dimensional printer according to a fourth embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments according to the present invention will be specifically described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic configuration diagram of a powder supply device 100 having a powder amount measuring device 2 according to the first embodiment. The powder supply device 100 includes a powder supply source 1 , a powder amount measuring device 2 and a controller 3 . According to this powder supply device 100, the amount of powder supplied per unit time can be measured in-situ by the powder amount measuring device 2. FIG. Further, based on the measurement result, the controller 3 can control the amount of powder supplied per unit to be a desired constant value.

A powder supply source 1 supplies powder. In this embodiment, since the powder amount is measured based on the charge amount of the powder, it is assumed that the powder to be supplied is a chargeable conductive powder (for example, copper powder). As a specific configuration example of the powder supply source 1, the powder supply source 1 includes a ball 11, a partition plate 12, a vibrator 13, a funnel 14, a housing 15, and a powder carrier gas supply source 16. and

Ball 11 contains powder. An opening is formed in the bottom surface of the ball 11, and the partition plate 12 is arranged in this opening. The vibrator 13 vibrates under the control of the controller 3 . As this vibration is transmitted to the ball 11 , the powder in the ball 11 drops from the opening into the funnel 14 . The funnel 14 guides the powder from the opening of the ball 11 to the powder quantity measuring device 2 . The housing 15 accommodates the balls 11 , the partition plate 12 , the oscillator 13 and the funnel 14 . A powder carrier gas supply source 16 supplies a powder carrier gas such as nitrogen gas into the housing 15 through an airflow tube so that the powder flows smoothly.

Here, the partition plate 12 is movable according to the control by the control unit 3, and depending on the position of the partition plate 12, the amount of powder supplied from the powder supply source 1 per unit time (hereinafter, unless otherwise specified, simply When the term "amount of powder" is used, it means the amount of powder supplied per unit time.) can be adjusted. Further, the amount of vibration of the vibrator 13 is variable according to the control by the control section 3, and the greater the amount of vibration, the greater the amount of powder supplied.

In this way, the powder supply source 1 can control the amount of powder supplied. However, while the amount of powder contained in the ball 11 is about 10 kg, the amount of powder supplied is about 1 g per minute, so it is difficult to strictly control the amount of powder.

Therefore, in this embodiment, a powder amount measuring device 2 for measuring the amount of powder is provided. The powder amount measuring device 2 measures the charge amount of the powder supplied from the powder supply source 1 to grasp the powder amount.

The powder amount measuring device 2 has, as the charge amount measuring section 21 , a powder guide path 211 , a metal tube 212 at least part of which is made of a metal member (not shown), and a sensor 213 .

Powder guide path 211 guides powder from powder source 1 to metal tube 212 . The surface of the powder guide path 211 and the surface of the connecting portion (material) between the powder guide path 211 and the metal tube 212 are made of, for example, Teflon, PVC, vinyl or other general insulating chemical substances. When the powder flows through the powder guide path 211 , the powder is charged due to contact friction between the powder and the surface of the powder guide path 211 .

The upper end of the metal tube 212 is connected to the powder guide path 211, and the lower end of the metal tube 212 supplies the powder to the supply target. Also, the sensor 213 is electrically connected to the metal member of the metal tube 212 .

The sensor 213 converts the amount of charge of the powder flowing through the metal tube 212 (the amount of charge charged to the powder) into an electric signal and outputs the electric signal. Specifically, the sensor 213 detects an electric charge on the powder when the powder comes into contact with the metal member of the metal tube 212 and outputs an electric signal corresponding to the charge amount to the control unit 3 . Therefore, the output of the sensor 213 (hereinafter simply referred to as "sensor output") corresponds to the charge amount of the powder. Since the amount of charge increases as the amount of powder supplied increases, the amount of charge of powder corresponds to the amount of powder.

In this way, the sensor output corresponds to the powder amount, and the powder charge amount corresponds to the powder amount, so the sensor output corresponds to the powder amount.

FIG. 2 is a diagram schematically showing the relationship between the sensor output and the amount of powder. As shown, the amount of powder and the sensor output are almost proportional. By obtaining such a relationship in advance as a calibration straight line, the controller 3 can grasp the amount of powder based on the sensor output.

Here, the constant of proportionality differs depending on the type of powder. For example, if the powder A has a higher density than the powder B, the powder B is more likely to be charged even if the powder amounts are the same. Therefore, even if the amount of powder is the same, the sensor output for powder B is larger.

Depending on the type of powder, the charge may exceed the detectable charge of the sensor 213 (powder C in FIG. 2). Specifically, while the supply amount is assumed to be 1 to 6 g, the supply amount is 3 g and the sensor output exceeds the maximum detectable value. In this case, when the amount of powder is 3 g or more, the amount of powder cannot be accurately grasped from the sensor output.

Therefore, in this embodiment, the powder quantity measuring apparatus 2 of FIG.

The charge amount adjusting section 22 adjusts the charge amount of the powder supplied from the powder supply source 1 . Then, the sensor 213 of the charge amount measuring unit 21 measures the charge amount of the powder whose charge amount has been adjusted. The charge amount of this powder corresponds to the amount of powder.

Here, the charge amount adjusting unit 22 reduces the charge amount of the powder, and the degree of reduction is variably adjusted. More specifically, the charge amount adjustment unit 22 adjusts the charge amount of the powder so that the charge amount of the powder falls within a predetermined range within the assumed supply amount range. This predetermined range corresponds to a measurable (detectable) range by the sensor 213 of the charge amount measuring section 21 . Specifically, the charge amount adjustment unit 22 reduces the charge amount of the powder so that the charge amount of the powder does not exceed the charge detectable by the sensor 213 .

A specific configuration example of the charge amount adjusting section 22 will be described below.

The charge amount adjusting section 22 has a metal tube 221 , at least a part of which is made of a metal member (not shown), and a sensitivity adjusting section 222 .

The metal tube 221 guides the powder from the powder supply source 1 to the powder guiding path 211 of the charge quantity measuring section 21 . The powder whose charge amount has been adjusted is charged again in the powder guide path 211 .

The sensitivity adjustment section 222 has a variable resistance element R and a variable capacitance element C. As shown in FIG. One end of the variable resistance element R is electrically connected to the metal member of the metal tube 221, and the other end is grounded. One end of the variable capacitance element C is electrically connected to the metal member of the metal tube 221, and the other end is grounded (via another variable resistance element (not shown) if necessary).

When the powder touches the metal member of the metal tube 221, part of the charge charged in the powder flows to the ground via the variable resistance element R or the variable capacitance element C and disappears (that is, the amount of charge is reduced). ). The smaller the resistance value of the variable resistance element R, the larger the amount of the DC component of the charged charge that is lost. Also, the greater the capacitance value of the variable capacitance element C, the greater the loss of the AC component of the charged charge. By adjusting the resistance value of the variable resistance element R and the capacitance value of the variable capacitance element C in this manner, the charge amount can be variably adjusted.

For example, powder C shown in FIG. 2 has a large amount of charge, and the sensor output exceeds the detectable maximum value. Therefore, the charge amount adjusting section 22 needs to reduce the charge amount of the powder C greatly. Therefore, the resistance value of the variable resistance element R is decreased (the charge amount adjusting section 22 is short-circuited to reduce the sensitivity to the maximum), and the capacitance value of the variable capacitance element C is increased. Thereby, the sensitivity of the sensor 213 can be lowered (see the dashed line in FIG. 2). In addition, it is possible to positively apply a potential to control the charge amount of the powder. If the sensitivity exceeding the maximum value cannot be adjusted by connecting the variable resistance element R or the variable capacitance element C, a positive potential is applied to the charge amount adjustment unit 22 to remove the powder that is in contact with the charge amount adjustment unit 22. removes the charge and lowers the sensitivity. Further, when the sensitivity of the powder is insufficient, a negative potential can be applied to the charge amount adjusting section 22 to positively charge the powder in contact with the charge amount adjusting section 22, thereby increasing the sensitivity.

On the other hand, the powder A shown in FIG. 2 has a small charge amount. Therefore, the charge amount adjusting section 22 does not need to reduce the charge amount of the powder A so much. Therefore, the resistance value of the variable resistance element R is increased and the capacitance value of the variable capacitance element C is decreased. Thereby, the sensitivity of the sensor 213 can be increased.

In this manner, the resistance value of the variable resistance element R and the capacitance value of the variable capacitance element C may be determined in advance according to the powder (type) to be supplied. Then, the user or the control section 3 sets the resistance value of the variable resistance element R and the capacitance value of the variable capacitance element C according to the powder (type) to be supplied.

In addition, by installing the metal tube 221 obliquely instead of vertically, the probability that the powder comes into contact with the metal tube 221 increases. Therefore, the amount of charge can be adjusted by changing the installation angle of the metal tube 221 . Also, the larger the area of the metal tube 221 that can be contacted by the powder (for example, the longer the metal tube 221 is), the higher the probability that the powder will come into contact with the metal tube 221 . Therefore, the charge amount can be adjusted by the area of the metal tube 221 .

Thus, the powder supply device 100 can measure the powder amount in real time because the powder amount measuring device 2 has the charge amount adjusting unit 22 and the charge amount measuring unit 21 .

The powder feeder 100 has a controller 3 . The control unit 3 grasps the amount of powder from the sensor output, and controls the amount of powder supplied from the powder supply source 1 based on the amount of powder. Specifically, the controller 3 controls the amount of powder supplied from the powder supply source 1 so that the amount of powder ascertained from the sensor output becomes a desired constant value.

Since the amount of powder and the sensor output correspond to each other as described above, it can be said that the control unit 3 controls the amount of powder supplied from the powder supply source 1 based on the sensor output. Specifically, it can be said that the controller 3 controls the amount of powder from the powder supply source 1 so that the sensor output becomes a desired constant value.

As a specific example of powder amount control, the control unit 3 controls the vibration amount of the vibrator 13 in the powder supply source 1 . More specifically, when the sensor output indicates that the amount of powder is greater than a desired value, the control unit 3 controls the vibration amount of the vibrator 13 to decrease. On the other hand, when the sensor output indicates that the amount of powder is smaller than the desired value, the control unit 3 controls the vibration amount of the vibrator 13 to increase. The control by the controller 3 may be feedback control or feedforward control.

Further, it is desirable to increase the amount of gas supplied from the powder carrier gas supply source 16 as the amount of powder increases. Therefore, the controller 3 may control the gas supply amount in accordance with the control of the powder amount.

Thus, in the first embodiment, the powder quantity measuring device 2 is provided in the powder supply device 100 . Therefore, the amount of powder supplied can be measured in real time.

In the powder amount measuring device 2, the charge amount adjusting unit 22 adjusts the charge amount of the powder supplied from the powder supply source 1, and then the charge amount measuring unit 21 measures the charge amount of the powder. . Therefore, the sensor 213 can measure the charge amount of the powder while the charge amount of the powder is within the measurable range of the sensor 213 in the charge amount measurement unit 21, and the supply amount of the powder can be accurately measured.

Since the powder supply amount can be measured with high accuracy, the control unit 3 can control the powder supply amount to be constant with high accuracy.

(Second embodiment)
A second embodiment described below applies the powder supply device 100 described in the first embodiment to a thermal spraying apparatus. More specifically, the present invention is applied to a thermal spraying apparatus that forms a film on a target with conductive powder supplied from a powder supply apparatus 100 .

FIG. 3 is a schematic configuration diagram of a thermal spraying apparatus according to the second embodiment. This thermal spraying apparatus includes a powder supply device 100, a thermal spraying nozzle 30, a plasma generation support gas supply unit 40, a chamber 50, a holder 60, a pressure adjustment gas supply unit 70, an exhaust pump 80, a cooling A wind supply unit 90 is provided, and film formation is performed on the target T held on the holder 60 in the chamber 50 .

The powder supply device 100 supplies conductive powder to the powder guide path 20 from its metal tube 212 (FIG. 1). A material derived from this conductive powder is deposited on the target T. As shown in FIG. As an example, the conductive powder is copper powder, and a copper thin film is formed on the target T. As described in the first embodiment, this powder feeder 100 can accurately keep the feed amount of powder constant.

The thermal spray nozzle 30 is also called a thermal spray gun, and melts the conductive powder and sprays it onto the target T (thermally sprays). The thermal spray nozzle 30 has a housing 31 , a cathode 32 and an anode 33 .

Housing 31 houses cathode 32 and anode 33 . A powder guide path 20 that guides powder from the powder feeder 100 to the cathode 32 penetrates the upper surface of the housing 31 . An opening is provided in the lower surface of the housing 31 and faces the holder 60 .

The cathode 32 is arranged on the downstream side (lower side) of the powder feeder 100 . A cavity is formed inside the cathode 32 , and the conductive powder from the powder feeder 100 passes through the cavity via the powder guide path 20 .

The anode 33 is arranged downstream (below) the cathode 32 and spaced from the cathode 32 . Anode 33 has a cavity formed therein. This cavity is located below the cavity of cathode 32 and above the opening in the lower surface of housing 31 . Conductive powder from the cathode 32 then passes inside the cavity in the anode 33 .

The plasma generation support gas supply unit 40 supplies plasma generation support gas such as Ar gas, mixed gas of Ar and H ₂ , He gas, Xe gas, Ne gas, N ₂ gas, etc. for generating plasma necessary for the purpose of use. is supplied into the housing 31 of the thermal spray nozzle 30 .

Chamber 50 is positioned below thermal spray nozzle 30 . An opening is provided in the upper surface of the chamber 50 and aligned with the opening in the lower surface of the housing 31 of the thermal spray nozzle 30 . A holder 60 for holding the target T is arranged below this opening. The holder 60 is mounted on an XY slider 61 (stage), and the XY slider 61 can move the holder 60 within a horizontal plane. A thermocouple 62 is provided in the holder 60, and the temperature of the XY slider 61 (directly and indirectly the temperature of the sample on the stage) is measured by the thermocouple 62, and preset so as not to damage the sample by heat. It is used as a control signal to interrupt the plasma spraying once when the temperature reaches the desired temperature.

The chamber 50 is connected to a pressure adjusting gas supply section 70, an exhaust pump 80, and a cooling air supply section 90 in order to properly control the thermal spraying environment when the molten conductive powder is thermally sprayed onto the target T. FIG. The pressure adjusting gas supply unit 70 supplies a pressure adjusting gas such as an inert gas such as Ar gas, He gas, Ne gas, or N ₂ gas into the chamber 50 to prevent oxidation of the sample. Maintain the pressure at a constant value (eg, 300 Torr). The evacuation pump 80 evacuates the inside of the chamber 50 . The cooling air supply unit 90 supplies cooling air to the cooling plate 51 arranged inside the chamber 50 .

In such a thermal spraying apparatus, a voltage is applied to generate a high potential difference between the cathode 32 and the anode 33 while the plasma generation supporting gas is supplied into the housing 31 of the thermal spraying nozzle 30 . This causes an arc discharge between cathode 32 and anode 33 . Plasma is generated between the cathode 32 and the anode 33 due to the arc discharge, and the heat melts (liquefies) the conductive powder from the powder feeder 100 . Molten conductive powder (liquid powder) is sprayed onto the target T to form a film.

By using the powder supply device 100 described in the first embodiment, the powder supply amount can be kept constant, and the film thickness can be made constant.

(Third Embodiment)
A third embodiment described below applies the powder supply apparatus 100 described in the first embodiment to a substrate polishing apparatus such as a chemical mechanical polisher. More specifically, the present invention is applied to a substrate polishing apparatus that generates slurry using conductive powder supplied from a powder supply device 100 and polishes a substrate with the generated slurry.

FIG. 4 is a schematic configuration diagram of a substrate polishing apparatus according to the third embodiment. This substrate polishing apparatus includes a powder feeder 100, a liquid feeder 101, a slurry mixer controller 102, a slurry mixer 103, a polishing table 104, a nozzle 105, and a substrate holder 106. there is

The powder feeder 100 feeds powder, such as ceria, which is a source of slurry. A liquid supply device 101 supplies a liquid such as pure water. The slurry mixer control device 102 controls the control unit 3 ( FIG. 1 ) of the powder supply device 100 to control the powder supply amount and the liquid supply amount from the liquid supply device 101 . The slurry mixer 103 receives the powder from the powder feeder 100 and the liquid from the liquid feeder 101 and mixes them to produce slurry.

The polishing table 104 is provided with a polishing pad 104a on its surface and is rotated by rotating a downwardly extending support shaft (not shown). A nozzle 105 supplies the slurry produced by the slurry mixer 103 onto the polishing pad 104a. The substrate holding part 106 holds the substrate in its lower part, and rotates the substrate by rotating the support shaft 106a extending upward. Further, the supported substrate comes into contact with (is pressed against) the polishing pad 104a by descending the support shaft 106a.

The substrate is polished by bringing the substrate held by the substrate holder 106 into contact with the polishing pad 104a supplied with slurry.

(Fourth embodiment)
A fourth embodiment described below applies the powder supply device 100 described in the first embodiment to a three-dimensional printer.

FIG. 5 is a schematic configuration diagram of a three-dimensional printer according to the fourth embodiment. This three-dimensional printer includes a powder supply device 100 , a laser device 110 , an XY stage 111 and a Z stage 112 .

The powder supply device 100 supplies metal materials such as SUS630, SUS316L, and SKD61 (H13 steel). The laser device 110 irradiates the metal material supplied from the powder supply device 100 with laser light based on the given three-dimensional model.

The XY stage 111 is a stage that moves within a horizontal plane. The Z stage 112 moves the XY stage vertically. Movement of the XY stage 111 and Z stage 112 is controlled based on the three-dimensional model.

With such a configuration, a three-dimensional object made of a metallic material and having a shape corresponding to the three-dimensional model is formed.

The above-described embodiments are described for the purpose of enabling a person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above-described embodiments can be naturally made by those skilled in the art, and the technical idea of the present invention can also be applied to other embodiments. Therefore, the present invention should not be limited to the described embodiments, but should have the broadest scope in accordance with the spirit defined by the claims.

100 Powder supply device 1 Powder supply source 11 Ball 12 Partition plate 13 Oscillator 14 Funnel 15 Case 16 Powder carrier gas supply source 2 Powder amount measuring device 21 Charge amount measuring unit 211 Powder guiding path 212 Metal tube 213 Sensor 22 Charge amount adjustment unit 221 Metal tube 222 Sensitivity adjustment unit R Variable resistance element C Variable capacitance element 3 Control unit 20 Powder guide path 30 Thermal spray nozzle 31 Case 32 Cathode 33 Anode 40 Plasma generation support gas supply unit 50 Chamber 51 Cooling Plate 60 Holder 61 XY Slider 62 Thermocouple 70 Pressure Adjusting Gas Supply Unit 80 Exhaust Pump 90 Cooling Air Supply Unit 101 Liquid Supply Device 102 Slurry Mixer Control Unit 103 Slurry Mixer 104 Polishing Table 104a Polishing Pad 105 Nozzle 106 Substrate Holding Part 106a Support shaft 110 Laser device 111 XY stage 112 Z stage

Claims (14)

a charge amount adjusting unit that adjusts the charge amount of the conductive powder supplied from the powder supply source;
a charge amount measuring unit that measures the charge amount of the powder whose charge amount has been adjusted and corresponds to the charge amount of the powder supplied from the powder supply source per unit time. measuring device. The powder amount measuring device according to claim 1, wherein the charge amount adjusting section adjusts the charge amount of the powder so that the charge amount of the powder falls within a predetermined range. 3. The powder amount measuring device according to claim 2, wherein said predetermined range corresponds to a measurable range of said charge amount measuring section. The charge amount adjustment unit has a metal member,
4. The powder amount measuring device according to claim 1, wherein the charge amount of the powder is reduced by contacting the metal member with the powder. The charge amount adjustment unit has a variable resistance element and a variable capacitance element,
5. The powder amount measuring device according to claim 4, wherein said metal member is grounded via said variable resistance element and grounded via said variable capacitance element. 6. The powder amount measuring device according to claim 5, wherein the resistance value of said variable resistance element and the capacitance value of said variable capacitance element are determined according to said powder. a powder supply source that supplies electrically conductive powder;
a charge amount adjustment unit that adjusts the charge amount of the powder supplied from the powder supply source;
a charge amount measuring unit for measuring the charge amount of the powder whose charge amount has been adjusted;
and a control unit that controls the amount of powder supplied from the powder supply source per unit time based on the output from the charge amount measurement unit. 8. The powder supply device according to claim 7, wherein the output from said charge amount measuring section corresponds to the amount of powder supplied from said powder supply source per unit time. 9. The powder according to claim 7, wherein the control unit controls the amount of powder supplied from the powder supply source per unit time to be constant based on the output from the charge amount measurement unit. body feeder. The powder source is
a ball containing the powder;
a vibrator that vibrates the ball,
10. The powder feeder according to any one of claims 7 to 9, wherein said controller controls the amount of vibration of said vibrator. a powder supply device according to any one of claims 7 to 10;
a first electrode provided with a first cavity through which powder from the powder feeder passes;
a second electrode provided with a second cavity through which powder from said first electrode passes;
A thermal spraying apparatus for forming a film on a target by thermally spraying powder with plasma generated between the first electrode and the second electrode. a powder supply device according to any one of claims 7 to 10;
a liquid supply;
a slurry mixer that mixes the powder from the powder supply device and the liquid from the liquid supply device to generate slurry;
a polishing table;
a nozzle for supplying the generated slurry to the polishing table;
A substrate polishing apparatus, comprising: a substrate holder that holds and rotates a substrate to be polished. a powder supply device according to any one of claims 7 to 10;
and a laser device that irradiates the powder from the powder supply device with a laser beam. adjusting the charge amount of the powder supplied from the powder supply source;
and measuring the charge amount of the powder whose charge amount is adjusted, the charge amount corresponding to the amount of powder supplied from the powder supply source per unit time.