JP2011168825A - Substrate treatment device and method for manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treatment device capable of reducing the frequency of maintenance and determining an appropriate time of maintenance. <P>SOLUTION: The substrate treatment device 10 includes: an ion source 40 for generating ions; a target 36 receiving an ion beam 45 from the ion source 40; a wafer holder 18 housed in a first vacuum chamber 11 and holding a wafer 1 that receives sputtered particles 46 from the target 36; an adhesion preventing plate 51 suppressing adhesion of sputtered particles 46 to a second vacuum chamber 22; and an adhesion amount predicting unit 61 predicting an adhesion amount of the particles 46 stuck to the adhesion preventing plate 51. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a substrate processing apparatus and a semiconductor device manufacturing method.

An example of a semiconductor device is an MRAM (Magnetic Random Access Memory). The MRAM is a memory using a spin injection magnetization reversal method. In the manufacturing method of MRAM, a thin film of several atomic layers is stacked to produce an MTJ (Magnetic tunnel Junction) element. An ultra-thin film sandwiching an insulating film (MgO film (magnesium oxide film) having a target value of 1 nm or less) with a magnetic film (CoFeB film) for utilizing inversion of electrons is the central portion of the film.
As an example in which an MTJ element manufacturing method and a vacuum processing apparatus used therefor are described, there is Patent Document 1.

JP 2006-124792 A

In a vacuum processing apparatus for producing an MTJ element, it is necessary to keep the ultimate pressure in the film forming chamber lower by ^10-7 Pascal (Pa) or less, which is an ultra-vacuum region.
In such a film formation chamber, when a target is sputtered by an ion beam, the target component adheres to the surface of the film formation chamber by sputtering, and if a certain amount of adhesion is exceeded, peeling occurs, so that cleanliness is maintained. I can't. In order to always maintain the film forming chamber, it is necessary to perform maintenance.
If the frequency of this maintenance is low, cleanliness cannot be maintained, and if the frequency is high, productivity is lowered.

  An object of the present invention is to provide a substrate processing apparatus that can reduce the frequency of maintenance and can easily determine an appropriate maintenance time, and a method of manufacturing a semiconductor device using the same.

Typical means for solving the above problems are as follows.
(1) an ion generator that generates ions;
A target housed in a storage container and receiving ions from the ion generator;
A substrate holder for holding a substrate that receives a target component from the target;
An adhesion suppression unit that suppresses the adhesion of the target component to the storage container;
An adhesion amount prediction unit for predicting the adhesion amount of the target component adhering to the adhesion suppression unit;
A substrate processing apparatus comprising:
(2) The target contained in the storage container is irradiated with ions from the ion generation unit, and the target component generated from the target is applied to the adhesion suppression unit and the substrate holding unit that suppress the adhesion of the target component to the storage container. Adhering to a held substrate;
And a step of predicting an adhesion amount of the target component adhering to the adhesion suppression unit by an adhesion amount prediction unit.

  According to this means, the maintenance frequency can be reduced, and an appropriate maintenance time can be easily determined.

It is a front view which shows the substrate processing apparatus which is 1st embodiment of this invention. FIG. (A) is the side surface sectional drawing, (b) is an enlarged view of the b section of (a). It is side surface sectional drawing which shows an ion source. It is side surface sectional drawing which shows other embodiment of an ion source. It is sectional drawing which shows the film-forming example of SPRAM. It is side surface sectional drawing which shows the locus | trajectory of a sputtered particle. It is a graph which shows a film-forming rate. It is a graph which shows the relationship between coefficient (alpha) and M2 + M1. The tilt block of the substrate processing apparatus which is 2nd embodiment of this invention is shown, (a) is a front view, (b) is sectional drawing which follows the bb line of (a). The quartz resonator is shown, (a) is a front view, (b) is a side view. It is a top view which shows the cluster type substrate processing apparatus which is 3rd embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 to 9 show a first embodiment of the present invention.
In this embodiment, a substrate processing apparatus according to the present invention is configured to manufacture an MRAM, and a plurality of thin films are stacked on a silicon wafer (hereinafter referred to as a wafer) as a substrate.

  As shown in FIGS. 1 to 3, the substrate processing apparatus 10 according to the present embodiment includes a first vacuum container 11 as a first storage container formed in a rectangular parallelepiped box shape. The container 11 constitutes a processing chamber 12. The front wall of the first vacuum vessel 11 is provided with an opening 13 for carrying the wafer 1 as a substrate into and out of the processing chamber 12. The opening 13 is opened and closed by a gate valve 14.

A tilt device 15 is installed on the right side wall of the processing chamber 12. The tilt device 15 is configured to be able to turn the tilt shaft 16 by a predetermined angle and, for example, reciprocates by 90 degrees. The tilt shaft 16 is inserted into the processing chamber 12. The tilt shaft 16 supports the tilt block 17 in the processing chamber 12. A wafer holder 18 as a substrate holder is disposed on the tilt block 17. A rotation device 19 is installed in the tilt block 17. The rotating device 19 rotates the wafer holder 18.
The tilt device 15 tilts the wafer 1 held by the wafer holder 18 between a horizontal posture and a vertical posture.
A lifting device 20 is installed on the bottom wall of the processing chamber 12. The elevating device 20 elevates and lowers the baffle plate 21 disposed in the processing chamber 12. The baffle plate 21 is disposed on the back side of the tilt block 17 and is lifted and lowered by the lifting device 20.

A second vacuum container 22 serving as a second storage container formed in a rectangular parallelepiped box shape is connected to the back wall of the first vacuum container 11. The second vacuum container 22 constitutes a target chamber 23. The volume of the target chamber 23 is larger than the volume of the processing chamber 12. That is, the volume of the processing chamber 12 is smaller than the volume of the target chamber 23.
A mating wall between the first vacuum container 11 and the second vacuum container 22 constitutes a partition wall 24 that partitions the processing chamber 12 and the target chamber 23. The partition wall 24 is provided with a communication hole 25 at a predetermined position. The predetermined position is a position where a part of ions irradiated and reflected by a target described later passes and the other part collides with the wall surface of the partition wall 24.
A turbo molecular pump 26 as a first vacuum pump and a cryopump 27 as a second vacuum pump are installed at the lower part of the back wall of the second vacuum vessel 22. The turbo molecular pump 26 and the cryopump 27 exhaust the target chamber 23, the processing chamber 12, and an ion source chamber described later.

A rotating device 28 is installed horizontally in the upper part of the back wall of the second vacuum vessel 22. A rotating shaft 29 of the rotating device 28 is horizontally inserted into the target chamber 23 so as to extend in the front-rear direction. The rotating shaft 29 is hermetically sealed with a magnetic seal. The rotating shaft 29 supports the target holder 30 in the target chamber 23.
A plurality of target holders 30 serving as extending portions are perpendicular to the rotation axis 29 and extend in different directions. Specifically, the target holder 30 is configured in a cone shape. For example, the target holder 30 is formed in an octagonal pyramid (octagonal pyramid) platform (truncated octagonal pyramid) shape. A rotation shaft 29 is connected to a cone rotation axis (vertical perpendicular) 31 through the target holder 30. As shown in FIG. 3, the included angle 33 formed by the rotation axis 31 of the cone and the cone surface 32 is set to an acute angle, for example, 45 degrees. That is, the included angle 33A formed by the surface 31A orthogonal to the rotation axis 31 and the conical surface 32 is 45 degrees.
The conical surface 32 includes eight trapezoidal side wall surfaces 34. The eight side wall surfaces 34 are located at equal intervals in the circumferential direction. The side wall surface 34 is in a direction perpendicular to the rotating shaft 29 and constitutes an extending portion extending in eight different directions. One target chuck 35 is installed on each of the eight side wall surfaces 34. The target chuck 35 holds the target 36 parallel to the side wall surface 34. Accordingly, the target 36 is inclined by 45 degrees with respect to the rotating shaft 29. The target 36 is formed as a flat rectangular parallelepiped. Further, adjacent ends of the adjacent targets 36 and 36 constitute a depression angle of 40 degrees as an acute angle. Therefore, the adjacent targets 36 and 36 sandwich a sufficient gap.
A cooling water channel (not shown) is piped to the target chuck 35 via the hollow portion of the rotating shaft 29. The cooling water suppresses heat generation due to ion irradiation of the target 36.

  An injection hole 39 is provided in the bottom wall of the second vacuum vessel 22. An ion source 40 is installed on the lower surface of the bottom wall of the second vacuum vessel 22. A target 36 is located above the injection hole 39. The target 36 inclined at 45 degrees faces the injection hole 39 and the communication hole 25.

As shown in FIG. 4, the ion source 40 includes an ion source chamber 41, a filament 42, a flat plate acceleration electrode 43, and a flat plate reduction electrode 44.
The ion source chamber 41 communicates with the target chamber 23 through the injection hole 39. The filament 42 is provided in the ion source chamber 41. The acceleration electrode 43 and the deceleration electrode 44 are provided so as to cross the injection hole 39. The acceleration electrode 43 and the deceleration electrode 44 face the filament 42. Electric power is supplied to the filament 42 from a filament power source and an arc power source, and voltages are applied to the acceleration electrode 43 and the deceleration electrode 44 from the acceleration power source and the deceleration power source.
The acceleration electrode 43 and the deceleration electrode 44 are formed of a heat-resistant metal, for example, molybdenum (Mo). The acceleration electrode 43 and the deceleration electrode 44 are arranged in parallel with a predetermined gap d. The acceleration electrode 43 has a plurality of acceleration passage holes 43a. The deceleration electrode 44 has a large number of deceleration passage holes 44a.
The deceleration passage hole 44a is arranged so that the axis is shifted (eccentric) with respect to the opposing acceleration passage hole 43a. This arrangement deflects the ion beam 45 from the acceleration electrode 43, so that the ion beam 45 converges on the target 36 as shown in FIG. Convergence of the ion beam 45 increases the ion beam density (current density) and increases the deposition rate, thereby suppressing the generation of impurities and preventing contamination of the wafer 1. This arrangement also makes the target 36 smaller and the ion source 40 smaller.

A gas supply source 50 is connected to the ion source 40. The gas supply source 50 supplies a gas to be ionized into the ion source chamber 41. As the gas, argon (Ar) gas is usually used.
When argon gas is supplied into the ion source chamber 41 and arc power is supplied to the filament 42, arc discharge occurs between the filament 42 and the side wall of the ion source chamber 41. Due to this arc discharge, argon positive ions (hereinafter referred to as argon ions) and electrons are mixed (plasma state). The accelerating electrode 43 and the decelerating electrode 44 impart kinetic energy to the argon ions, thereby drawing the argon ions into the target chamber 23 through the accelerating passage hole 43a and the decelerating passage hole 44a.
Argon ions extracted into the target chamber 23 become an ion beam 45 and irradiate the target 36. The ion beam 45 irradiated to the target 36 knocks out particles 46 (hereinafter, referred to as sputtered particles) whose components are constituent materials of the target 36 from the target 36. The sputtered particles 46 fly in the target chamber 23 and the processing chamber 12 with a large mean free path, and adhere to the wafer 1 in the processing chamber 12. The sputtered particles 46 adhering on the wafer 1 are deposited to form a thin film containing the constituent material of the target 36 as a component.

FIG. 5 shows another embodiment of the ion source.
The acceleration electrode 47 and the deceleration electrode 48 in the ion source 40A according to the present embodiment are formed in a spherical shape that is curved so that the surface facing the target 36 is a concave surface. The multiple acceleration passage holes 47a and the multiple deceleration passage holes 48a formed in the acceleration electrode 47 and the deceleration electrode 48 respectively face each other. The opposed pair of acceleration passage hole 47a and deceleration passage hole 48a are located on the same axis, and the axis is directed to the center of the spherical surface.
The accelerating electrode 47 and the decelerating electrode 48 that are curved on the concave surface converge the ion beam 45. Therefore, the ion source 40A according to the present embodiment has the same operations and effects as the ion source 40 according to the embodiment.

  As shown in FIG. 3, the substrate processing apparatus 10 includes a controller 60, and the controller 60 includes a personal computer, a panel computer, or the like. The controller 60 controls the tilt device 15, the wafer holder 18, the rotation device 19, the lifting device 20, the turbo molecular pump 26, the cryopump 27, the rotation device 28, the ion source 40 and the gas supply source 50.

Hereinafter, an embodiment of a method for manufacturing a semiconductor device according to the present invention will be described with respect to a thin film forming step in a method for manufacturing a SPRAM (Spin Transfer Torque Magnetic Rondom Access Memory) using the substrate processing apparatus having the above-described configuration.
SPRAM is a kind of MRAM and reverses spin injection magnetization.
FIG. 6 is a cross-sectional view showing an example of SPRAM film formation.
In this film formation example, a Ta (tungsten) film is formed on a wafer made of SiO ₂ (silicon dioxide) or Si (silicon) material, a PtMn film is formed on the Ta film, a CoFe film is formed thereon, and a first Ru ( Ruthenium) film, 1st CoFeB film, MgO film, 2nd CoFeB film, 2nd Ta film, 2nd Ru film are laminated in this order, and 9 layers of metal films are laminated in total 6 kinds of film types Is done.

The controller 60 controls the following operations of the substrate processing apparatus.
In the initial state, the gate valve 14 closes the opening 13. The tilt device 15 maintains the tilt block 17 in a horizontal posture and releases the wafer holder 18. The rotating device 19 is stopped. The lifting device 20 has the baffle plate 21 positioned at the lower limit.
The target holder 30 maintains the home position. That is, the target holder 30 makes the target chuck 35 holding the Ta target 36 face the ion source 40.
The internal pressures of the processing chamber 12, the target chamber 23, and the ion source chamber 41 are maintained at 10 ⁻⁵ Pa (pascal) or more and 10 ⁻⁷ Pa or less by exhausting the cryopump 27.

In the wafer loading step, the controller 60 switches from the cryopump 27 to the turbo molecular pump 26 to maintain the internal pressures of the processing chamber 12, the target chamber 23, and the ion source chamber 41 at 10 ⁻³ Pa or more and 10 ⁻⁴ Pa or less. The gate valve 14 opens the opening 13. A wafer transfer device (not shown) carries the wafer 1 into the processing chamber 12 from a preliminary chamber (not shown) and transfers it onto the wafer holder 18. The wafer holder 18 holds the wafer 1.

In the depressurization step, the controller 60 switches the turbo molecular pump 26 to the cryopump 27 after closing the opening 13 by the gate valve 14, and changes the processing chamber 12, the target chamber 23, and the ion source chamber 41 to 10 ⁻³ Pa or more and 10 ^−4. Vacuum is pulled from an internal pressure of Pa or lower to 10 ⁻⁶ Pa.
Subsequently, the cryopump 27 is switched to the turbo molecular pump 26, and the internal pressures of the processing chamber 12, the target chamber 23, and the ion source chamber 41 are maintained at 10 ⁻⁷ Pa.

In the film forming (Ta) step, the gas supply source 50 supplies argon gas to the ion source chamber 41. Electric power is supplied to the filament 42, and a voltage is applied to the acceleration electrode 43 and the deceleration electrode 44. If necessary, the neutralization power source is turned on.
The tilt device 15 shifts the tilt block 17 to a vertical posture that is a processing position. The rotating device 19 rotates the wafer 1. The elevating device 20 raises the baffle plate 21 to a predetermined position.
When the arc power is supplied, the ion source 40 irradiates the target 36 composed of Ta with the ion beam 45. The ion beam 45 irradiated to the target 36 knocks out sputtered particles 46 made of Ta from the target 36. The sputtered particles 46 fly into the processing chamber 12 and adhere to the wafer 1 held by the wafer holder 18. The sputtered particles 46 adhered on the wafer 1 are deposited to form a Ta film. At this time, the internal pressures of the processing chamber 12, the target chamber 23, and the ion source chamber 41 are maintained at 10 ⁻² Pa.
When a preset processing time has elapsed, the arc power supply is turned off. If the neutralization power is on, turn it off. The internal pressures of the processing chamber 12, the target chamber 23, and the ion source chamber 41 at this time are maintained at 10 ⁻² Pa or more and 10 ⁻³ Pa or less.

In the next film formation (PtMn) step, the rotating device 28 rotates the target holder 30 so that the PtMn target 36 faces the ion source 40 and the wafer 1. If necessary, the power value of the filament 42 is changed, and the voltage values of the acceleration electrode 43 and the deceleration electrode 44 are changed.
Subsequently, if necessary, the supply amount is adjusted, argon gas is supplied to the ion source chamber 41, power is supplied to the filament 42, voltage is applied to the acceleration electrode 43 and the deceleration electrode 44, and necessary. Accordingly, the neutralization power source is turned on. The rotating device 19 rotates the wafer 1. If necessary, the lifting device 20 raises the baffle plate 21 to a predetermined position.
When the arc power source is turned on, the ion source 40 irradiates the target 36 composed of PtMn with the ion beam 45. The ion beam 45 irradiated to the target 36 knocks out sputtered particles 46 made of PtMn from the target 36. The sputtered particles 46 fly into the processing chamber 12 and adhere to the Ta film of the wafer 1 held by the wafer holder 18. The sputtered particles 46 adhered on the Ta film of the wafer 1 are deposited to form a PtMn film.
When a preset processing time has elapsed, the arc power supply is turned off. If the neutralization power is on, turn it off.

  Thereafter, the controller 60 sequentially deposits and stacks various films shown in FIG. 6 on the wafer 1 by switching the target 36 to be used in accordance with the film forming step described above.

As the last film formation step, when the second Ru film formation step is completed, the controller 60 performs a wafer unloading step.
In the wafer unloading step, the power supply to the filament 42 is stopped, the voltage application to the acceleration electrode 43 and the deceleration electrode 44 is stopped, and the neutralization power source is turned off as necessary. Return the Ta target 36 to the home position. When the rotation device 19 stops rotating and the elevating device 20 lowers the baffle plate 21 to the lower limit position, the tilt device 15 shifts the tilt block 17 to the horizontal posture. The supply of argon gas to the ion source chamber 41 is stopped. At this time, the internal pressures of the processing chamber 12, the target chamber 23, and the ion source chamber 41 are maintained at 10 ⁻⁵ Pa or more and 10 ⁻⁷ Pa or less.
When the internal pressures of the processing chamber 12, the target chamber 23, and the ion source chamber 41 are maintained at 10 ⁻³ Pa or more and 10 ⁻⁴ Pa or less, the gate valve 14 opens the opening 13. The wafer transfer device picks up the processed wafer 1 from above the wafer holder 18 and carries it out of the processing chamber 12 to the spare chamber (wafer unloading).

By the way, the sputtered particles 46 that are target components fly and adhere to the inner surface of the target chamber 23 formed by the second vacuum container 22 that is a container for the target 36. When the adhering sputtered particles 46 exceed a certain adhering amount, they are separated and become a generation source of particles, so that maintenance for cleaning the inner surface of the target chamber 23 is required.
Therefore, in the present embodiment, a deposition preventing plate 51 as an adhesion suppressing unit that suppresses adhesion of the target component to the storage container is detachably laid in the target chamber 23 so as to cover the inner surface of the target chamber 23. Yes. A peeling prevention portion 52 is formed on the surface of the deposition preventing plate 51 facing the target 36 side. The peeling preventing part 52 is formed by roughing the surface by blasting or the like.
In the present embodiment, since the inner surface of the target chamber 23 is covered with the deposition preventing plate 51, the sputtered particles 46 do not adhere to the inner surface of the target chamber 23, so that the maintenance for cleaning the target chamber 23 itself is not performed. It becomes unnecessary.

On the other hand, since the sputtered particles 46 adhere to the deposition preventing plate 51, maintenance for cleaning is necessary. However, since the peeling prevention part 52 is formed on the deposition preventing plate 51, it is possible to prevent the deposited film of the attached sputtered particles 46 from being peeled off. That can be suppressed.
When the amount of sputtered particles 46 exceeding the delamination preventing function in the delamination preventing unit 52 is deposited, the deposited film is also delaminated on the deposition preventing plate 51, and thus the deposition preventing plate 51 becomes a particle generation source. Therefore, maintenance for cleaning the deposition preventing plate 51 is also required.

  Therefore, in the present embodiment, the controller 60 is provided with an adhesion amount prediction unit 61 that predicts the adhesion amount of the target component that adheres to the adhesion suppression unit. The adhesion amount prediction unit 61 according to the present embodiment is a program that monitors the irradiation amount of the ion beam 45 onto the target 36 and calculates the adhesion amount of the sputtered particles 46 onto the deposition preventing plate 51 from the film formation rate.

Next, the adhesion amount prediction unit 61 according to the present embodiment will be described.
In general, the film formation rate is proportional to the square of the reciprocal of the distance ratio from the target 36.
Further, the sputtered particle density distribution of the sputtered particles 46 that reach the wafer 1 from the target 36 approximates the cos Θ curve distribution. As shown in FIG. 7, Θ is an incident angle of the ion beam 45 with respect to the target 36. There is a high probability that the sputtered particles 46 exist somewhere within the range of the end spread shown by the broken line in FIG. 7, and in particular, there is a high probability that the sputtered particles 46 are most frequently present near the center line of the broken line.
As shown in FIG. 7, the position of the deposition preventing plate 51 where the sputtered particles 46 adhere most to the deposition preventing plate 51 is near the upper edge of the communication hole 25, and the distance to the target 36 is closer than the wafer 1. But the angle is different (away from the centerline).
The adhesion amount Q of the sputtered particles 46 at the position where the sputtered particles 46 adhere most to the deposition preventing plate 51 (near the upper edge of the communication hole 25) can be calculated by the following equation (1).
Q = V × (La / Lb) ² × K × T (1)
In the formula (1), V is a deposition rate on the wafer 1, La is a distance between the wafer 1 and the target 36, Lb is a distance between the deposition preventing plate 51 and the target 36, K is an angle constant, and T is an ion beam 45. Irradiation time.
The allowable adhesion amount at which peeling does not occur on the deposition preventing plate 51 is approximately 1000 nm.
Therefore, in the formula (1), by setting Q = 1000, the irradiation time T of the ion beam 45 reaching the allowable adhesion amount can be obtained. The adhesion amount predicting unit 61 predicts the calculated irradiation time T as a time when peeling occurs on the deposition preventing plate 51, and when the cumulative irradiation time of the ion beam 45 reaches the predicted time T, Alarm the maintenance time.
Note that the angle constant K varies depending on the emission angle of the target 36, and thus is obtained from experimental values. In this embodiment, it is about 0.8.
The film formation rate of the wafer 1 is as shown in FIG. 8 and can be represented by a substantially proportional expression. The film formation rate can be estimated even if the output of the ion source 40 is changed finely.

By the way, since the target 36 is consumed by sputtering, it is necessary to replace it with a new one with a certain amount of consumption.
Therefore, in this embodiment, the target wear prediction unit 62 is provided in the controller 60. The target consumption prediction unit 62 is a program that monitors the irradiation time of the ion beam 45 to the target 36 and calculates the replacement time of the target 36.

Next, the target consumption prediction unit 62 according to the present embodiment will be described.
Various formulas have been proposed for target consumption. According to the Sigmund equation, the sputtering rate (representing how many sputtered particles are sputtered by one ion) Y is expressed by the following equations (2) and (3).
Y = 0.076 × α × Tm / U (2)
Tm = 4 × M1 × M2 × E / (M1 + M2) ² (3)
In equations (2) and (3), α: coefficient, U: target binding energy, M1: ion mass number, M2: target mass number, E: ion beam energy.
FIG. 9 shows the relationship between the coefficient α and M2 + M1.
Since the sputtering rate Y can be obtained from the equations (2), (3), and FIG. 9, the consumption amount of the target can be grasped.

  According to the embodiment, the following effects can be obtained.

(1) The accumulated irradiation time of the ion beam is monitored by a controller, and when the threshold value is exceeded, an alarm is generated, so that the deposition plate is Maintenance such as replacement can be started.

(2) Since the generation of particles due to sputtered particles can be prevented by performing appropriate maintenance, film formation can always be maintained in a highly clean atmosphere and a stable environment.

(3) If only the cumulative irradiation time of the ion beam is monitored, it is difficult to accurately grasp the amount of deposition and the amount of consumption because the sputtering rate differs for each target. By grasping the irradiation time of the ion beam for each target and using the target wear prediction unit, it is possible to grasp the more accurate adhesion amount and wear amount.

10 and 11 show a second embodiment of the present invention.
The difference between this embodiment and the first embodiment is how to determine the film formation rate.
In the present embodiment, a quartz balance (Quarts Crystal Microbalance, hereinafter referred to as QCM) 54 as a film thickness detector is installed in the processing chamber 12 in order to more accurately predict the adhesion amount of the sputtered particles 46 to the deposition preventing plate 51. Then, the film formation rate is predicted using the detection result of the QCM 54.
In the present embodiment, the QCM 54 is mounted on a tilt block 17 that tilts the angle of the wafer 1. The wiring 57 is drawn out of the processing chamber 12 through the hollow portion of the tilt block 17 formed in a hollow shape.
As shown in FIG. 11, the QCM 54 has a structure in which a pair of electrodes 56, 56 are formed on the end face of the crystal unit 55, and when a substance adheres to the surface of the electrode 56 of the crystal unit 55, its mass This is a mass sensor that measures a very small amount of mass change by utilizing the property that the resonance frequency fluctuates (decreases) in response to.
When the adhesion amount Q to the deposition preventing plate 51 is predicted based on the film formation rate Vq measured by the QCM 54, the following equation (4) is used.
Q = Vq × (La / Lb) ² × K × T (4)
In Expression (4), La is the distance between the wafer 1 and the target 36, Lb is the distance between the deposition preventing plate 51 and the target 36, K is an angle constant, and T is the irradiation time of the ion beam 45.
In equation (4), the distance La between the wafer 1 and the target 36 may be the distance between the QCM 54 and the target 36. However, since it is an approximate number, any may be used. That is, La includes the meaning of the distance between the wafer 1 and the target 36 and the distance between the QCM 54 and the target 36.
The method for obtaining the maintenance time of the deposition preventing plate in the present embodiment is the same as in the first embodiment. According to this embodiment, the same operation and effect as the first embodiment can be obtained.

By using the QCM 54, the following control is possible.
The filament 42, the target 36, and the like in the ion source 40 are consumed every time the film is formed, and the film thickness on the wafer 1 may vary.
For example, the filament 42 of the ion source 40 becomes thinner and becomes less current as electrons are emitted. Reducing the current means that the amount of emitted electrons is reduced, and that the acceleration current when irradiating the ion beam 45 is reduced. If the replacement time of the filament 42 is wrong, the filament 42 is cut during film formation, and the film formation process is interrupted. As a result, the wafer 1 during film formation may be wasted.
Further, since the target 36 is sputtered, the state of the surface is gradually consumed as the film is deposited, and the emission state of the sputtered particles also changes.
If the ultimate pressure fluctuates after maintenance of the substrate processing apparatus or the like, the film formation rate fluctuates due to changes in the plasma density in the ion source 40 and the energy of the ion beam 45, thereby forming a thin film. It becomes a serious problem for a substrate processing apparatus such as an apparatus that requires high film thickness accuracy.
When the QCM 54 is installed in the processing chamber 12, the film formation rate value as a result of detection by the QCM 54 is smaller than the film formation rate value in the normal state and is not more than a predetermined value. In this case, it can be determined that the filament 42 is consumed.
On the other hand, since the surface of the target 36 becomes concave due to the sputtering, the emission angle to be sputtered fluctuates, so that the sputter rate fluctuates.
Therefore, when the QCM 54 is installed in the processing chamber 12, the sputtering rate (deposition rate) can be monitored in-line by the QCM 54, and the film formation time can be changed.
As described above, by installing the QCM 54, it becomes possible to determine the maintenance time of the substrate processing apparatus, and the maintenance can be performed efficiently. As a result, the substrate processing apparatus can be operated efficiently.

The QCM 54 has a limit on the amount that the crystal resonator 55 can adhere to.
Therefore, when installing in the processing chamber 12, as shown in FIG. 10, it is desirable to perform measurement by exposing the quartz crystal resonator 55 to a sputtering atmosphere only when measurement is desired by providing a shutter 58 or the like. When a certain amount of adhesion is reached, the crystal unit 55 is replaced with a new one.

FIG. 12 shows a third embodiment of the present invention.
This embodiment is different from the first embodiment in that the QCM 54 is installed in each of the processing chambers 12 of a plurality of sputtering apparatuses of the cluster type substrate processing apparatus.
Also in the present embodiment, by installing the QCM 54, it becomes possible to determine the maintenance time of the cluster type substrate processing apparatus, and the maintenance can be performed efficiently, so that the cluster type substrate processing apparatus can be operated efficiently. .

  In addition, this invention is not limited to the said embodiment, It cannot be overemphasized that it can change variously in the range which does not deviate from the summary.

  For example, the QCM is not limited to the film thickness detector.

  The substrate is not limited to a wafer, but may be a printed wiring board, a liquid crystal panel, a magnetic disk, a compact disk, or the like.

Preferred embodiments of the present invention will be additionally described.
(1) an ion generator that generates ions;
A target housed in a storage container and receiving ions from the ion generator;
A substrate holder for holding a substrate that receives a target component from the target;
An adhesion suppression unit that suppresses the adhesion of the target component to the storage container;
An adhesion amount prediction unit for predicting the adhesion amount of the target component adhering to the adhesion suppression unit;
A substrate processing apparatus comprising:
(2) The substrate processing according to (1), wherein the adhesion suppression unit includes a peeling prevention unit having a rough surface and is detachably laid on the storage container so as to cover the inner surface. apparatus.
(3) The substrate processing apparatus according to (1) and (2), wherein the adhesion amount prediction unit monitors an irradiation amount of the ion generation unit to the target and predicts an adhesion amount of the target component from a film formation rate.
(4) The substrate processing apparatus according to (1) or (2), wherein the adhesion amount prediction unit predicts the adhesion amount of the target component from a film formation rate measured by a film thickness detector.
(5) The substrate processing apparatus according to (4), wherein the film thickness detector is a QCM.
(6) The substrate processing apparatus according to any one of (1) to (5), wherein a target consumption prediction unit that monitors irradiation time of the ion generation unit to the target and predicts consumption of the target is installed.
(7) The target contained in the storage container is irradiated with ions from the ion generation unit, and the target component generated from the target is applied to the adhesion suppression unit and the substrate holding unit that suppress the adhesion of the target component to the storage container. Adhering to a held substrate;
And a step of predicting an adhesion amount of the target component adhering to the adhesion suppression unit by an adhesion amount prediction unit.

1 ... wafer (substrate),
DESCRIPTION OF SYMBOLS 10 ... Substrate processing apparatus, 11 ... First vacuum container, 12 ... Processing chamber, 13 ... Opening, 14 ... Gate valve,
DESCRIPTION OF SYMBOLS 15 ... Tilt apparatus, 16 ... Tilt axis | shaft, 17 ... Tilt block, 18 ... Wafer holder (substrate holder), 19 ... Rotation apparatus,
20 ... Lifting device, 21 ... Baffle plate,
22 ... second vacuum container (storage container), 23 ... target chamber, 24 ... partition wall, 25 ... communication hole, 26 ... turbo molecular pump (first vacuum pump), 27 ... cryopump (second vacuum pump), 28 ... Rotating device, 29 ... rotating shaft, 30 ... target holder, 31 ... rotating axis (vertical perpendicular), 31A ... plane orthogonal to the rotating axis, 32 ... conical surface, 33 ... depression angle, 34 ... side wall surface, 35 ... target chuck , 36 ... Target,
DESCRIPTION OF SYMBOLS 39 ... Injection hole, 40 ... Ion source, 41 ... Ion source chamber, 42 ... Filament, 43 ... Acceleration electrode, 44 ... Deceleration electrode, 43a ... Acceleration passage hole, 44a ... Deceleration passage hole, 45 ... Ion beam, 46 ... Spatter Particles 47 ... Accelerating electrode 47a ... Acceleration passage hole 48 ... Deceleration electrode 48a ... Deceleration passage hole 50 ... Gas supply source
DESCRIPTION OF SYMBOLS 51 ... Adhesion board (adhesion suppression part), 52 ... Peeling prevention part, 54 ... QCM (quartz balance), 55 ... Quartz crystal oscillator, 56 ... Electrode, 57 ... Wiring, 58 ... Shutter,
60 ... Controller, 61 ... Adhesion amount prediction unit, 62 ... Target consumption prediction unit.

Claims (2)

An ion generator for generating ions;
A target housed in a storage container and receiving ions from the ion generator;
A substrate holder for holding a substrate that receives a target component from the target;
An adhesion suppression unit that suppresses the adhesion of the target component to the storage container;
An adhesion amount prediction unit for predicting the adhesion amount of the target component adhering to the adhesion suppression unit;
A substrate processing apparatus comprising: The target contained in the storage container is irradiated with ions from the ion generation unit, and the target component generated from the target is held by the adhesion suppression unit and the substrate holding unit that suppress the adhesion of the target component to the storage container. Adhering to the substrate;
And a step of predicting an adhesion amount of the target component adhering to the adhesion suppression unit by an adhesion amount prediction unit.

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