JP4483795B2 - Delivery mechanism and processing device - Google Patents

Description

The present invention relates to a delivery mechanism and a processing apparatus for forming a film on a semiconductor wafer or the like using a gas.

In general, when a semiconductor integrated circuit is manufactured, a film deposition (CVD) process, a thermal oxidation and impurity diffusion process, an etching process, and a film formation (sputtering) are performed on a semiconductor wafer (hereinafter referred to as a wafer) to be processed. In each manufacturing process such as a process and a heat treatment process, processing by various processing apparatuses is performed.
In the film growth process, a thin film such as a silicon oxide film (SiO ₂ ) or silicon nitride (SiN) is deposited as an insulating layer or an insulating film on the wafer surface using, for example, a CVD (chemical vapor deposition) apparatus. In addition, the wiring pattern and the recess are filled with tungsten (W), tungsten silicide (WSi), titanium (Ti), titanium nitride (TiN), titanium silicide (TiSi), tungsten nitride (WN), tantalum oxide ( Thin films such as Ta ₂ O ₅ ), tantalum (Ta), tantalum nitride (TaN), hafnium oxide (HfO ₂ ), zirconium oxide (ZrO ₂ ), and protactium oxide (PaO ₃ ) are deposited.

When each processing is performed by these processing apparatuses, generation of particles that cause a decrease in product yield must be avoided as much as possible.
In general, this type of particle is often generated by peeling off an unnecessary film attached to the inner wall surface of the processing chamber, the surface of an internal structure such as a mounting table or a shower head structure, and therefore, regularly, for example, When a film of 25 wafers per lot is formed, or a cleaning gas such as ClF ₃ gas is flowed into a processing chamber irregularly, the above-described unnecessary film is removed. By performing such a cleaning process, unnecessary films adhering in the processing chamber are removed, and generation of particles can be suppressed.

By the way, since the cleaning gas is very active, when the cleaning process is performed for an excessively long time, not only an unnecessary film adhered to the inner wall surface of the processing chamber or the surface of the structure in the chamber but also the chamber Since the surface of itself and the internal structure of the chamber itself are scraped off by etching little by little, determining an appropriate end point of the cleaning process in order to perform a cleaning process that is not too short and not too long is Very important.
Conventionally, in order to determine the end point of this cleaning process, for example, it is determined that a cleaning process is performed every time a predetermined number of wafers, for example, 25 wafers in one lot are formed, and 25 sheets are processed. When the wafer is deposited, it is determined in advance how long the cleaning process should be performed in order to remove unnecessary deposited films accumulated in the processing chamber. When actually processing the wafer continuously, for example, every time 25 wafers are processed, the cleaning process is executed in the cleaning process period determined as described above.

In the method of determining the cleaning processing period, for example, when a processing chamber in which 25 wafers are formed is cleaned, the top surface of the mounting table is observed from a viewing window provided in the processing chamber. At the moment when the unnecessary film is almost completely removed, the color of the mounting table surface changes instantaneously from the color of the film to the color of the component material of the mounting table. It can be recognized that it has been completely removed.
Note that the time when the surface of the mounting table changes instantaneously from the color of the deposited film to the original color of the constituent material of the mounting table as described above is referred to as “just etch”.

  In the actual etching process, the etching process is not terminated at the time of the just etch described above, but an unnecessary film is attached to other parts, for example, parts that are more difficult to remove than the surface of the mounting table. In order to completely remove the unnecessary film in this portion, the etching process is continued for a predetermined period further than the point of just etching, and the etching process is terminated. This extended period is about ½ times the time required from the start of the cleaning process to the point of just etching. Therefore, if 300 seconds are required from the start of the cleaning process to the point of just etching, the cleaning process is continued for 150 seconds. Finally, the cleaning process is performed for a total of 450 seconds to reach the end point of the etching process.

By the way, when a large number of wafers are continuously processed, the cleaning process may be performed as described above every time a predetermined prescribed number of films, for example, 25 films are formed. There are many cases where the film forming apparatus has to be in an idling state for a long time just by forming a film, for example, several wafers. In this case, there is a risk that the adhered film may be altered by long idling. Therefore, the cleaning process as described above must be executed immediately before entering the idling state.
In this case, the thickness of the unnecessary film adhering in the processing chamber is much thinner than the planned film thickness, so that the structure in the chamber can be obtained by performing the cleaning process of the prescribed length described above. There are also cases where the surface of an object such as a mounting table, shield ring, shower head structure, etc. is scraped by excessive etching, or corrosion damage to the surface of the member, etc., and shortens the life of these structures. There was a problem such as. Further, if the frequency of replacement of the structure is increased, there is a problem that the number of maintenances such as replacement of parts is increased correspondingly, the operation rate of the apparatus is decreased, and the throughput is decreased.

Furthermore, there has been a problem that a large amount of relatively expensive cleaning gas is consumed as a result of performing an extra cleaning process.
On the other hand, it is conceivable to create a program that appropriately changes the cleaning process period according to the number of wafers processed before the cleaning process, but in this case, not only the number of programs increases. However, it is not realistic because the operator is forced to make significant changes to the existing program and consequently the operator executes it.
The present invention has been devised to pay attention to the above problems and to effectively solve them. The object of the present invention is to determine the appropriate end point of the etching process by automatically and reliably grasping the time of the just etch regardless of the number of processed objects before the start of the cleaning process. It is an object of the present invention to provide a processing apparatus and a cleaning method capable of cleaning an unnecessary film deposited therein.
It is another object of the present invention to provide a delivery mechanism and a processing apparatus that can prevent a contact that generates particles or a collision or sliding that damages a push-up pin.

As a result of earnest research on the cleaning processing method, the present inventors have found that there is a correlation between the amount of generated particles and the time of just etching, and the time of just etching is automatically determined by using particle measuring means. Obtaining the knowledge that it can be recognized has led to the related art of the present invention.
The related art of the present invention includes a processing chamber that can be evacuated, a mounting table on which an object to be processed to be subjected to predetermined processing is mounted, a gas supply unit that supplies a necessary gas to the processing chamber, Particles provided in the exhaust system for measuring the number of particles contained in the exhaust gas in a processing apparatus having an exhaust system that evacuates the atmosphere in the processing chamber by interposing a vacuum pump in the middle And a cleaning end point determining unit that determines an end point of the cleaning process based on a measurement value of the particle measuring unit when a cleaning process is performed by flowing a cleaning gas into the processing chamber. Is a processing device.

By configuring in this way, the number of particles exhausted from the processing chamber is measured by the particle measuring means provided in the exhaust system, and after the number of particles reaches a peak over time, it decreases and becomes less than a predetermined amount. This time is automatically recognized as the point of just etch, and the end point of the cleaning process can be set appropriately.
Therefore, it is possible to prevent the cleaning process from being performed excessively long, regardless of the number of processed objects before the cleaning process is performed. In addition, useless consumption of the cleaning gas can be suppressed.

The present invention mainly relates to FIGS. 20 to 25 and, as defined in claim 1, is used when delivering an object to be processed to a mounting table provided in a processing chamber that can be evacuated. In the delivery mechanism, a gap is provided between the inner wall of the pin insertion hole provided in the mounting table and a space that allows gas to flow through the space on the mounting surface side and the space on the back surface side of the mounting table. is set to a length that fits within the depth of the pin insertion hole while being fitted Te opening and a plurality of push-up pins its distal end abuts the rear surface of the workpiece, the lower end of each push pin A plurality of positioning drive pins that support the push-up pins with upper end portions penetrating into the fit holes, and push-up members that commonly support the lower ends of the positioning drive pins, Drive the push-up member up and down And an actuator, the outer diameter of the upper portion of the positioning drive pin, the fit to allow clearance for suppressing heat transfer between the push pin and the positioning drive pin and between the side wall of the fitting hole while being set smaller than the inner diameter of Goana, the the positioning drive pin is a transfer mechanism which is characterized that you flange portion for supporting the lower end of the push-up pin is formed.
In this case, for example, as defined in claim 2, the positioning drive pin is provided with a stopper for restricting the positioning drive pin from rising .

Further, for example, as prescribed in請Motomeko 3, the lower end of the positioning drive pin is fixed by a nut with adjustable fixed position relative to the push-up member.
According to a fourth aspect of the present invention, there is provided a delivery mechanism used when delivering an object to be mounted to a mounting table provided in a processing chamber that can be evacuated, and the inner wall of a pin insertion hole provided in the mounting table. Between the space on the mounting surface side of the mounting table and the space on the back surface, the space is inserted through a gap that allows gas to flow and fits within the depth range of the pin insertion hole. A plurality of push-up pins whose lengths are set to be in contact with the back surface of the object to be processed, fitting holes formed by opening the lower ends of the push-up pins, and upper ends thereof into the fitting holes a plurality of positioning drive pin for supporting the fitted through has been the push pin, wherein the push-up member for supporting the lower end of each positioning drive pin in common, and an actuator for vertically driving said push-up member, before Symbol positioning drive pin The outer diameter of the upper part is set smaller than the inner diameter of the fitting hole so that a gap for suppressing heat transfer between the push-up pin and the positioning drive pin is formed between the side wall of the fitting hole. a transfer mechanism which is characterized that you have been configured to support the push-up pins only at the upper end of the positioning drive pin.

In this case, as specified for example in請Motomeko 5, constriction at the bottom along with provided the fitting hole, the upper end of the positioning drive pin, the maximum outer diameter dimension of the constriction A bulging portion protruding in a flange shape is provided so as to be larger than the minimum inner diameter dimension.
Further, for example, as specified in請Motomeko 6, wherein the constriction and the swollen portion, by screwing, or are made to engage and disengaged by the keyway and key projections.
Further, for example , as defined in claim 7 , a flange portion that functions as a stopper when the push-up pin descends is provided at a lower end opening portion of the pin insertion hole.
According Ru engaged to claim 8 invention, a processing chamber that is adapted to be evacuated, the mounting table for mounting the object to be processed which is subjected to predetermined processing, a gas supply means for supplying a required gas into the processing chamber when an exhaust system for evacuating the vacuum pump the atmosphere of the processing chamber, and delivery mechanism of claim 1 to 7 Neu deviation or claim used for the mounting table when passing the object to be processed , A processing apparatus comprising:

According to the delivery mechanism and the processing apparatus of the present invention, the following excellent operational effects can be exhibited.
When the workpiece is delivered, the push-up pin inserted into the pin insertion hole moves up and down smoothly with little contact, preventing collisions and sliding that may cause particles to come into contact with the push-up pin and damage the push-up pin. can do.
In addition, since the space between the back surface of the object to be processed and the mounting surface of the mounting table and the space on the back surface side (downward) of the mounting table communicate with each other through a gap, The mounting position that occurs when the space is created from the state where the back surface of the object to be processed and the mounting surface of the mounting table are in close contact when the gas existing in the space escapes to the space or when the object to be processed rises Can be prevented and the object to be processed can be prevented from dropping.
Further, since the push-up pin and the positioning drive pin are provided, heat generated in the mounting table is hardly transmitted to the positioning drive pin, and thermal deformation of the positioning drive pin can be prevented.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a configuration example of a processing apparatus of the present invention equipped with particle measuring means, FIG. 2 is a plan view showing the positional relationship between a transmission window and an exhaust port in the processing chamber, and FIG. FIG. 4 is a block diagram showing the cleaning end point determining means, and FIG. 5 is an explanatory diagram for explaining the principle of determining the end point of the cleaning process. In this embodiment, a CVD apparatus that performs a film forming process on a semiconductor wafer (hereinafter referred to as a wafer) as an object to be processed will be described as an example of the processing apparatus. Of course, the present invention can be similarly applied to all other processing apparatuses that require a cleaning process such as a sputtering apparatus and an etching apparatus. Further, here, as the CVD apparatus and the particle measuring means, those previously disclosed by the present applicant in Japanese Patent Laid-Open No. 2001-59808 are used.
That is, as shown in the figure, this CVD apparatus 2 is roughly divided into a processing unit 4 for performing film forming processing on the wafer W with a film forming gas, and an exhaust system for exhausting the atmosphere and film forming gas in the processing unit 4. 6 and a particle measuring means 8 for measuring the number of particles in the exhaust gas flowing through the exhaust system 6 is provided. The particle measuring means 8 includes a measurement main body 10 and a control / processing unit 12 that controls this operation. The control / processing unit 12 may be incorporated in a system control unit (not shown) that controls the entire processing apparatus, or may be separate. The particle measuring means 8 is connected to a cleaning end point determining means 14 which will be described in detail later.

  The processing unit 4 includes a processing chamber 16 formed in a cylindrical shape or a box shape by using, for example, aluminum (Al). A cylindrical reflector 18 that extends upward from the bottom of the processing chamber is disposed in the processing chamber 16. A concentric cylindrical support column 54 is provided on the outer periphery of the reflector 18, and a mounting table 20 on which the wafer W is mounted is mounted on the support column 54. The reflector 18 is made of, for example, aluminum with a mirror-coated surface as a heat ray reflective material, and the mounting table 20 is a heat ray of carbon material having a thickness of about 1 mm, aluminum nitride (AlN), black AlN, or the like. It is formed of a ceramic member having high absorption and heat transfer coefficient.

  A plurality of, for example, three lifter pins 22 (only two are shown in the illustrated example) that move up and down simultaneously are disposed below the mounting table 20. The lifter pins 22 are mounted on the mounting table 20 by a drive system (not shown). The wafer W is lifted from the lower surface through the provided lifter pin holes 24. The wafer W is lifted up by these lifter pins 22 and is transferred into and out of the processing chamber by delivery with a transfer mechanism having an arm or the like (not shown). Further, the lifter pin 22 is integrally formed with a rod-shaped clamp support portion 23, and a clamp ring 25 is attached to the upper end of the lifter pin 22 so as to press and fix the peripheral portion of the wafer W to the mounting table 20. It has become. Accordingly, the space between the processing space S and the lower side of the mounting table 20 is hermetically sealed, and it is possible to prevent the film formation gas from flowing around the back surface of the wafer W or the lower side of the mounting table 20 to form a film.

Furthermore, a transmission window 28 made of a heat ray transmitting material such as quartz is provided at the bottom of the processing chamber directly below the mounting table 20 so as to hermetically seal the inside of the chamber. Further below that, a box-shaped heating chamber 30 is provided so as to surround the transmission window 28.
In the heating chamber 30, a plurality of heating lamps 32 are mounted on a turntable 34 that also serves as a reflecting mirror as a heating source. The turntable 34 is connected to a motor 36 by a rotating shaft and is rotated according to the rotation of the motor 36. By this rotation, the wafer W can be heated uniformly.

The heating light emitted from the heating lamp 32 passes through the transmission window 28 and is irradiated from the lower surface side of the mounting table 20 to heat the back surface of the wafer W. As a heating source, a resistance heater may be embedded in the mounting table 20 in place of the heating lamp 32.
Further, a shower head section 40 as a gas supply means having a large number of gas injection holes 38 for introducing a processing gas such as a film forming gas into the processing chamber 16 is provided on the processing chamber ceiling facing the mounting table 20. It has been. The shower head portion 40 is formed into a circular box shape, for example, from aluminum or the like, and is provided with gas inlet ports 41, 42, 43 for connecting to a gas inlet system (not shown) and supplying gas. The two gas introduction ports 41 and 42 are supplied with respective film forming gases, mixed in the gas mixing unit 45, and introduced into the diffusion chamber 47 below. A diffusion plate 27 having a large number of diffusion holes is provided in the diffusion chamber 47 so as to diffuse the introduced mixed gas. A cleaning gas supply pipe 44 is connected to the remaining gas introduction ports 43. A flow rate controller 46 and an opening / closing valve 48 are sequentially provided in the cleaning gas supply pipe 44 so that, for example, ClF ₃ gas can be flowed as a cleaning gas during the cleaning process. Accordingly, each gas supplied from the gas inlets 41, 42, 43 of the shower head 40 flows into the diffusion chamber 47 in the shower head 40 and is diffused by the diffusion plate 27, and then the gas injection hole. 38 is injected into the processing space S.

Further, a shield ring 26 is provided on the outer peripheral side of the mounting table 20, and a ring-shaped rectifying plate 52 having a number of rectifying holes 50 on the outer periphery thereof is vertically moved by a support column 54 formed in an annular shape. Supported in direction. A through hole 57 is provided in the side wall of the support column 54, and a relief valve 29 is attached to the through hole 57, so that the pressure adjustment between the upper and lower sides of the wafer W is performed. Sometimes, the pressure difference between the pressure under the mounting table 20 and the processing space S is eliminated so that the wafer W does not flutter. A plurality of exhaust ports 56 are provided at the bottom of the chamber below the rectifying plate 52.
FIG. 2 is a plan view showing the positional relationship between the transmission window and the exhaust port in the processing chamber of FIG. As shown in FIG. 2, in this embodiment, four exhaust ports 56 are arranged at substantially uniform gaps along the periphery of the bottom, and each exhaust port 56 is provided with an exhaust port 58.
And this exhaust port 58 is airtightly connected to each exhaust pipe 60 which becomes a part of the exhaust system 6 by interposing a gasket or welding by a coupling (not shown).

These exhaust pipes 60 have a straight pipe shape at the rising portion, and are connected to a collecting pipe 62 having a relatively large diameter, with the discharge sides being gathered into one. For example, a butterfly valve 64 is provided in the collecting pipe 62 in order to adjust the pressure in the processing chamber 16. A vacuum pump 66 such as a turbomolecular pump is connected to the discharge side of the collecting pipe 62, and a main exhaust pipe 68 having a relatively large diameter is connected to the discharge side of the vacuum pump 66. The atmosphere, film forming gas, and the like in the chamber are discharged from the chamber to the outside through the main exhaust pipe 68 by the vacuum pump 66.
Then, as described above, the measurement main body 10 of the particle measuring device 8 is attached to one or more of the four exhaust pipes 60 of the CVD apparatus.

Here, a film forming process using this CVD apparatus will be described.
First, the gate valve G provided on the side wall of the processing chamber 16 is opened, the wafer W is loaded into the processing chamber 16 by a transfer arm (not shown), the wafer W is transferred to the lifter pins 24 raised, the transfer arm is moved away, and the gate is moved. Close valve G. Then, the lifter pins 24 are lowered to place the wafer W on the mounting table 20, and the outer peripheral edge of the wafer W is pressed by the inner peripheral edge of the clamp ring 25, and then the atmosphere in the processing chamber 16 is exhausted from the exhaust system 6. At this time, the relief valve 29 is operated to reduce the pressure difference between the pressure on the lower side of the mounting table 20 and the pressure on the wafer W side. This is to prevent the wafer W from fluttering when the processing chamber 16 is evacuated, thereby suppressing the generation of particles.

Next, various gases are supplied to the showerhead unit 40 as a processing gas from a processing gas source (not shown). For example, WF ₆ gas (film formation gas) and N ₂ gas are supplied to the gas inlet 42, and SiH ₄ gas and H ₂ gas are supplied to the gas inlet 41. Each gas is mixed in the gas mixing unit 45, diffused in the diffusion chamber 47 through the diffusion holes of the diffusion plate 27, and supplied approximately uniformly from the gas injection holes 38 to the processing space S.
The supplied film forming gas is also sucked and exhausted from each exhaust port 56 to the exhaust system 6 side, and the inside of the processing chamber 16 is set to a predetermined degree of vacuum. In addition, the heating lamp 32 is caused to emit light while rotating the rotating table 34, and the back surface side of the mounting table 20 is irradiated with heating light to be heated. Then, by heating the mounting table 20, the wafer W is quickly heated to a predetermined temperature, for example, 350 to 700 ° C. and maintained.
In such an atmosphere in the processing chamber 16, a predetermined chemical reaction occurs in the film forming gas, and, for example, a W (tungsten) film is deposited on the surface of the wafer W.

Further, the film forming gas in the processing chamber 16 flows down as exhaust gas from the exhaust ports 56 through the exhaust pipe 60 and joins in the collecting pipe 62. Is discharged from the main exhaust pipe 68 to the outside of the system. Here, the number of particles contained in the exhaust gas is measured by the particle measuring means 8.
Further, when the wafer W is processed continuously or intermittently in this way, a command to perform a cleaning process periodically (for example, every time 25 sheets are processed) or irregularly is issued, for example, by a host computer (not shown). Etc. This cleaning process is performed by supplying ClF ₃ gas into the processing chamber 16 via the cleaning gas supply pipe 44, whereby the inner wall of the processing chamber 16 and the structure in the chamber, such as the mounting table 20, Unnecessary films adhering to the surfaces of the shield ring 26, the shower head portion 40, and the like are removed. Even during the cleaning process, the particle measuring means 8 measures the number of particles contained in the exhaust gas in order to determine the end point of the cleaning process.

Next, the particle measuring unit 8 and the cleaning end point determining unit 14 will be described.
First, as shown in FIG. 3, the measurement main body 10 of the particle measuring means 8 includes a laser light irradiation unit 70 having a laser element that emits a very thin beam of laser light L, and a central axis 72 of the exhaust pipe 60. Scattered light detection comprising a stopper member 74 disposed on the side facing the laser beam irradiation unit 70 and a light receiving element provided on the tube wall in a direction substantially perpendicular to the irradiation direction of the laser beam L Part 76. Here, the laser element is a miniaturized semiconductor laser element such as GaAlAs, and an output of several W to several tens W is appropriate. Here, a high-power YAG laser can be used as the semiconductor laser element.

The laser beam irradiation unit 70 is provided on the tube wall so that the laser beam L to be irradiated follows a line segment connecting the chamber central axis 78 and the cross-sectional center point O of the central axis 72 (see FIG. 1) of the exhaust pipe 60. ing.
Further, the irradiation direction may be any direction as long as the irradiated laser light L passes through the cross-sectional center point O and goes in the direction in which the chamber center axis 78 is positioned. However, the relative positional relationship with the scattered light detection unit 71 is maintained.
The stopper member 74 absorbs the laser light L so that, for example, irregular reflection of the laser light L into the exhaust pipe 60 does not occur.

As shown in FIG. 3, a scattered light detector 71 made of, for example, a light receiving element is provided on the tube wall in a direction substantially orthogonal to the irradiation direction of the laser light L, and is included in the exhaust gas. Scattered light SL generated by irradiating the particle P with the laser light L can be received. And the center of the scattered light detection part 71 does not go to the cross-sectional center point 72, but is arrange | positioned at offset distance H3 offset as shown in FIG. The output of the scattered light detection unit 71 is supplied to the control / processing unit 12 where the number of particles per unit time is measured. Here, the unit time can be set to 0.1 seconds or more, but here, for example, 2 seconds is set, and the number of particles every 2 seconds is output to the cleaning end point determination means 14 as a measured value. The output of the cleaning end point determination means 14 is output to an apparatus host computer 79 that controls the overall operation of the CVD apparatus 2 and controls, for example, the on-off valve 48.
A control system incorporating parameters to be controlled in advance may be provided. As this parameter, it is possible to perform an optimum film formation method by providing means such as film thickness measurement, pressure gauge, film formation gas concentration, component, film quality measurement, etc. in the chamber transfer system and the unload system.

Next, the cleaning end point determination means 14 will be described with reference to FIGS.
As shown in FIG. 5, when the ClF ₃ gas is flowed into the processing chamber 16 and the cleaning process is started, a large amount of particles are generated after a while, and the time point when the number of particles is reduced to about several will be described later. Thus, the point of almost just etching is reached, so this point is automatically detected and the end point of the cleaning process is determined based on this point.
As shown in FIG. 4, the cleaning end point determination means 14 receives the measurement value from the control / processing section 12, and determines the number of particles for determining whether or not the measurement value is equal to or less than a predetermined particle threshold value. And a low particle number duration measuring unit 80 for measuring the duration during which the measured value is not more than a predetermined threshold based on the output of the particle number determining unit, and based on the output of the measuring unit 80 A just etch time determination unit 82 that determines a just etch time, an overetching period determination unit 84 that determines an overetching period based on a cleaning process period up to the just etch time, and a cleaning process based on the overetching period And an end point determination unit 86 for determining the end point of the main point. The cleaning end point determining means 14 is composed of, for example, a microcomputer, and the operation of each part is executed by software. The operation is controlled by the control unit 89.

In the present embodiment, as described above, the number of particles is measured as a unit time, for example, at intervals of 2 seconds, and the measured value is output from the control / processing unit 12 and input to the particle number determination unit 81. In the particle number determination unit 81, it is determined whether the number of particles is less than a threshold value, for example, ten. Then, the determination result is inputted to the next low particle number duration measuring unit 80.
Here, the low particle number duration measuring unit 80 outputs the time during which the state where the number of particles is a predetermined particle threshold, for example, 10 or less, that is, the low particle number duration is output. Note that the value of the threshold value “10” for the number of particles at this time is merely an example, and is not limited thereto, and can be set to one or more.
Further, the just etch time determination unit 82 determines whether or not the low particle number continuation time has continued for a predetermined time threshold, for example, 16 seconds (corresponding to 8 unit times), and the time threshold is exceeded. At that time, the time point that is the time threshold value, that is, the time point that is back by 16 seconds from that time point, is determined as the just etch time point.
Note that the time of the above time threshold, that is, the time when 16 seconds have elapsed may be set as the just etch time. The time threshold value is merely an example, and is not limited thereto, and is about 1 to 300 seconds, for example. Preferably, it is about 1 to 60 seconds.

Next, the over-etching period determining unit 84 determines the over-etching period by multiplying the cleaning process period T up to the point of just etching by a predetermined coefficient k. The coefficient k is determined in advance by the film condition of the deposited film, the cleaning conditions such as the temperature and the cleaning gas flow rate, and is usually in the range of about 0.1 to 1, preferably 0.2 to 0.6. In this embodiment, for example, “0.5” is set as the coefficient k.
Next, when the over-etching period is determined, the end-point determination unit 86 recognizes that the time point when the over-etching period (k · T) is further added to the just etching time point is the end point of the cleaning process. Then, when the overetching period has elapsed from the time of the just etch, an operation of closing the on-off valve 48 is performed to stop the supply of the cleaning gas.

As shown in FIG. 5, the operation for determining the end point of the cleaning process described above hardly generates particles for a while after the supply of the ClF ₃ gas as the cleaning gas is started. After the above number of particles is detected, control is performed to start.
Here, since the correlation between the point of just etch and the increase / decrease in the number of particles was actually examined, the examination result will be described with reference to FIG.
6A shows the increase or decrease in the number of particles when the cleaning process is performed after the WSi film is formed on the five semiconductor wafers, and FIG. 6B shows the WSi film on the 25 semiconductor wafers. An increase / decrease in the number of particles when the cleaning process is performed after the film forming process is performed is shown.

Here, ClF ₃ gas is used as the cleaning gas, and the surface of the mounting table in the processing chamber is observed through a viewing window provided in the chamber wall, and the color of the surface of the mounting table changes. Is the point of just etch. Note that the scale of the vertical axis is different between FIG. 6 (A) and FIG. 6 (B). In addition, time values on the horizontal axis represent hours, minutes, and seconds.
As shown in the figure, when the ClF ₃ gas is supplied to start the cleaning process, almost no particles are generated for about 50 seconds. This is considered to be a time lag from when the cleaning gas on-off valve 48 (see FIG. 1) is opened until the cleaning gas enters the processing chamber 16. Then, particles are generated abruptly after about 50 seconds have passed, and then decrease once after reaching a peak. At this time, in the case of processing 25 wafers shown in FIG. 6B, after suddenly detecting a large peak value once, the particles are greatly reduced for about 10 seconds, and then again the particles. The number increases to the second peak, and then the number of particles gradually decreases. As described above, since the measurement pattern varies depending on the thickness of the deposited film, as described above, in the just etch time determination unit 82, for example, the detection state in which the number of particles per unit time (2 sec) is 10 or less is continued for about 16 sec. The point of time may be set as the just etch point.

Then, when the detection state of the number of particles of 10 or less continues for 16 seconds under the conditions described with reference to FIG. 4, the particle measurement means 8 determines a time point that goes back 16 seconds before that time. It was set as the time of just etch.
As a result, in the case shown in FIG. 6A, the point of just etch is 57 seconds from the start of cleaning when visually observed, and 54 seconds in the case of the particle measuring means 8, and the difference is only 3 seconds. there were.
In the case shown in FIG. 6B, the point of just etch is 135 seconds from the start of cleaning when visually observed, and 134 seconds in the case of the particle measuring means 8, and the difference is only 1 second. It was almost correlated.

As described above, the just etch time determined using the parameter measuring unit 8 as described above is substantially the same as the just etch time determined in the case of visual observation, and is performed almost accurately and automatically. It was confirmed that the time point could be determined. That is, regardless of the number of wafers processed before the start of cleaning, the time during which particles are generated by etching with the cleaning gas can be measured, and the overetching time can be automatically and accurately determined based on this time.
Therefore, as described above, if the overetching time determined for this predetermined etching time, that is, the overetching process for a predetermined time is executed, the operation by the operator can be performed regardless of the number of wafer processes. Even if it is not necessary, if it is set in advance in the apparatus host computer and the APC (Advanced Process Control) control system, the cleaning process without excess or deficiency can always be executed.

Here, with reference to FIG. 7, the process of determining the etching end point will be described in more detail.
First, when a command for starting a cleaning process is issued from a host computer or the like (not shown), the cleaning program starts (S1), thereby starting the supply of the cleaning gas into the processing chamber 16 (see FIG. 1) (S2). ). Then, measurement of the elapsed time of the cleaning process is also started.
Next, it is determined whether or not the initial time t1 (see FIG. 5) has elapsed after the start of the supply of the cleaning gas (S3). This is because particles are not generated immediately after the supply of the cleaning gas is started, but particles are not generated for a while even if the cleaning gas is supplied into the processing chamber. It is to make it. The initial time t1 is, for example, about 1 to 120 seconds, although it depends on the supply amount of the cleaning gas. It should be noted that even if particle measurement is performed during the initial time t1, there will be no problem unless the arithmetic processing described below is performed based on the measurement value.

If the initial time t1 has elapsed, the particle measuring means 8 starts measuring the number of particles in the exhaust gas (S4). At this time, that is, when the initial time t1 has elapsed, as shown in FIG. 5, a sufficiently large number of particles are generated by the cleaning process. Therefore, the measured value of the number of particles at this time surely becomes a value far larger than ten. The measurement value of the particle measuring unit 8 is input to the particle number determining unit 81 of the cleaning end point determining unit 14, and it is determined whether the number of particles is 10 or less (S5).
Next, this determination result is input to the low particle number duration measuring unit 80, and if the number of particles is 10 or less, it is determined whether or not the previous measured value is 10 or less (S6). ). Here, in the case of NO, that is, when the number of particles exceeds 10 in the immediately preceding measurement value, this means that the number of particles has decreased below the threshold value for the first time, and this time point is the just etch time point. Since there is a possibility, the elapsed time T from the start of supply of the cleaning gas to the present time is stored. The elapsed time T is updated when the measured value of the number of particles once becomes 10 or less, becomes 10 or more again, and then becomes 10 or less again.

  Next, it is determined whether or not the state where the measured value of the number of particles is equal to or less than the threshold value (10) continues for a predetermined time (16 sec) (S8). This determination is executed without going through step S7 even when the determination in step S6 is NO, that is, when the measured value of the number of particles is continuously equal to or less than the threshold value. In this step S8, in the case of NO, that is, for example, when the low particle number duration for which the measured value of the number of particles is 10 or less is 16 sec or less, the process returns to step S5 and the measurement of the number of particles is continued. The In other words, in steps S5, S6, S7, and S8, the low particle number continuation time in which the measured number of particles is 10 or less is measured. Then, it is determined whether or not the low particle number continuation time has continued for a predetermined time threshold, for example, 16 seconds (S8), and when that time has continued for 16 seconds, the time point 16 seconds later than that time is determined as the just etch time point. (S9). The steps S5, S6, S7, and S8 constitute the low particle duration measuring unit 80 and the just etch time determining unit 82.

  The cleaning processing time up to the time of going back 16 seconds is the previously stored time T. As described above, the time point when the low particle number state continues for 16 seconds without going back 16 seconds may be the just etch time point. Based on this result, the overetching period determining unit 84 determines the overetching period by executing the “cleaning etching period T · coefficient k” (S10). Then, based on this overetching period, the end point determination unit 86 determines the end point of the etching process (S11). When the end point of the cleaning process is reached (S12), the supply of the cleaning gas is stopped (S13), and the etching process is ended. The particle size to be measured can be variously selected within a range of 0.01 μm or more by selectively setting parameters in the control / processing unit 12.

In this way, as described above, an appropriate and substantially accurate just etch time can be obtained regardless of the number of wafers processed before the start of the cleaning process, and the end point of the cleaning process is determined based on this. By setting the apparatus host computer or the APC control system in advance, the cleaning process can be automatically performed at an appropriate time without any excess or deficiency and without any operation by the operator.
Accordingly, damage to the processing chamber and its structure can be reduced, the life can be extended, and wasteful consumption of expensive cleaning gas can be prevented.

Although the unnecessary WSi film cleaning process has been described as an example here, the present invention is not limited to this, and the present invention can be applied to any film cleaning process, for example, a Ti film, a W film, a WN film, and the like. The present invention can also be applied to cleaning processing of TiN film, Ta film, TaOx film, SiO ₂ film, SiN film, SiON film, TaN, HfO ₂ , ZrO ₂ , PaO _{3 and the} like.
Also, the cleaning gas is not limited to ClF ₃ gas, and the present invention can be applied to other cleaning gases such as NF ₃ , ClF, and HF.
Although the semiconductor wafer is described as an example of the object to be processed here, the present invention is not limited to this, and the method of the present invention can be applied to a glass substrate, an LCD substrate, a compound semiconductor substrate, and the like.

<First Modification>
Next, a case where the present invention is applied to a processing apparatus of a different form for forming a TiN film will be described.
FIG. 8 is a block diagram showing a first modification of the processing apparatus of the present invention.
That is, here, the central portion of the bottom of the processing chamber 90 is recessed downward, and a support column 94 is erected from the bottom of the recess 92, and a heater (not shown) is incorporated at the upper end. A mounting table 96 is attached. The mounting table 96 and the support column 94 are made of ceramic such as AlN. Then, the ceiling of the processing chamber 90 that faces the mounting table 96, and provided with a shower head 98, the actual structure includes TiCl ₄ gas and a reducing gas as a source _gas, NH _{3, N} 2, Ar is a matrix structure that flows separately. A lifter pin 100 that pushes up the wafer is provided below the mounting table 96 so as to be lifted and lowered by an actuator 102 provided below the chamber, so that the TiCl ₄ gas and the reaction byproduct NH ₃ Cl do not liquefy or adhere. For example, it is heated to about 150 to 170 ° C.

In addition, a temperature control mechanism including a Peltier element 104 and a cooling jacket 106 is provided at the bottom of the processing chamber 90 so that the TiCl ₄ gas and the reaction byproduct NH ₃ Cl are not liquefied or adhered, for example, 150 to It is heated to about 170 ° C. In the column 94, a heater wiring 108 and a thermocouple wiring 110 are provided. Further, an exhaust pipe 112 provided with a vacuum pump (not shown) is connected to the bottom side wall of the recess 92, and the measurement main body 10 of the particle measuring means 8 described in the previous embodiment is connected to the exhaust pipe 112. Further, a control / processing unit 12 and a cleaning end point determination means 14 may be provided. A baffle plate 114 having a large number of ventilation holes is provided at the upper end of the recess 92. In this manner, TiN ₄ gas, NH _3, and N ₂ gas are supplied from the shower head unit 98 into the processing chamber 90, and TiN is formed on the wafer surface disposed on the mounting table 96 heated to a desired temperature. Make a film.

Since the parameter measuring means 8 is provided for cleaning unnecessary films in the processing chamber as in the embodiment of WSi film formation, as described above, regardless of the number of wafers processed before the start of the cleaning process. Therefore, it is possible to obtain an appropriate and substantially accurate just etch time point. Based on this, the end point time of the cleaning process is determined and set in advance in the apparatus host computer or the APC control system. The cleaning process can be automatically performed at an appropriate time without any operation by the operator.
Accordingly, damage to the processing chamber and its structure can be reduced, the life can be extended, and wasteful consumption of expensive cleaning gas can be prevented.
In the first modified example, since the particle measuring means 8 is provided in the single exhaust pipe 112, the number of particles in the exhaust gas can be captured more accurately.

<Second Modification>
Next, a case where the present invention is applied to a processing apparatus that forms a Ti film by plasma CVD will be described.
FIG. 9 is a block diagram showing a second modification of the processing apparatus of the present invention.
That is, here, the inside of the shower head portion 122 provided on the ceiling portion of the processing chamber 120 is a space 126 for source gas TiCl ₄ gas, Ar gas, and a cleaning gas ClF ₃ gas, and a reducing gas H ₂ gas and NH _3. The material gas and the reducing gas are supplied from the injection holes b through the spaces 126 and 124 without being mixed until they are injected into the processing chamber 120. A shower head portion 122 having a so-called postmix structure (matrix structure) is used. The spaces 124 and 126 are connected to the pipes 130 and 132, respectively, and serve as insulation when RF power having a frequency of 450 kHz to 60 MHz is supplied to the shower head unit 122. The plasma is stably generated in the processing chamber 120. Is generated. The shower head unit 122 is connected to a high frequency power source 136 through a matching circuit 134, and the shower head unit 122 is used as an upper electrode. The shower head unit 122 is supported on the ceiling of the processing chamber 120 via a ring-shaped insulator 138 made of alumina.

Further, a ring-shaped filling 140 made of, for example, quartz is disposed on the side surface side of the shower head portion 122. A heater 142 is provided on the upper surface of the shower head unit 122 and is heated at a desired temperature, for example, 100 to 200 ° C. so that the film forming gas (TiCl ₄ gas) is not liquefied. Yes. A heat insulating material 144 made of ceramic such as Al ₂ O ₅ or resin is provided on the upper side of the shower head portion 122, and cooling air can be supplied to the upper and lower spaces. And the temperature of the shower head part 122 is controllable to appropriate temperature, for example, 50-500 degreeC. Further, a shield box 146 for preventing high-frequency leakage is formed so as to cover the entire upper portion with the shower head portion 122. Reference numeral 145 denotes an embedded heater for heating the shower head unit 122.

On the other hand, the mounting table 147 in which the lower electrode is embedded is supported by the upper end of the support column 150 erected from the bottom of the recess 148 formed by recessing the bottom of the chamber into a recess. An exhaust pipe 150 provided with a vacuum pump (not shown) is connected to the bottom side wall of the recess 148. The measurement main body 10 of the particle measuring means 8 described in the previous embodiment is connected to the exhaust pipe 150. Further, a control / processing unit 12 and a cleaning end point determination means 14 may be provided.
In this way, the mounting table 147 is supplied by supplying TiCl ₄ gas, H _2, and Ar gas into the processing chamber 120 from the matrix-structured shower head unit 128 that is not mixed, and heated to a desired temperature, for example, 500 to 700 ° C. A Ti film is formed on the wafer.

Since the parameter measuring means 8 is provided for cleaning unnecessary films in the processing chamber as in the embodiment of WSi film formation, as described above, regardless of the number of wafers processed before the start of the cleaning process. Therefore, it is possible to obtain an appropriate and substantially accurate just etch time point. Based on this, the end point time of the cleaning process is determined and set in advance in the apparatus host computer or the APC control system. The cleaning process can be automatically performed at an appropriate time without any operation by the operator.
Accordingly, damage to the processing chamber and its structure can be reduced, the life can be extended, and wasteful consumption of expensive cleaning gas can be prevented.

<Third Modification>
Next, a processing apparatus that etches a natural oxide film by inductively coupled plasma (ICP) will be described as an example of the processing apparatus. FIG. 10 is a block diagram showing a third modification of the processing apparatus of the present invention. This processing apparatus is substantially the same as that disclosed by the present applicant in Japanese Patent Application No. 2001-1152.
As shown in the figure, the processing apparatus 726 includes a cylindrical aluminum processing chamber 728 having, for example, a ceiling portion opened. A disc-like mounting table 730 made of ceramic such as aluminum nitride (AlN) is mounted on the upper surface of the processing chamber 728 on the upper surface of the processing chamber 728. In the mounting table 730, a resistance heater 732 as a heating unit and a bias electrode 734 for applying a high-frequency voltage are embedded in advance as necessary.

The mounting table 730 is formed with a plurality of, for example, three pin holes 736 (only two are shown in FIG. 1) penetrating the mounting table 730 in the vertical direction. A push-up pin 740 made of, for example, quartz connected in common by 738 is accommodated in a loosely fitted state. The connecting ring 738 can be pushed up by a lifting rod 742 penetrating the bottom of the processing chamber 728 so as to move up and down. The pushing pin 740 can be moved up and down to lift or lower the wafer W. It is like that. Further, a metal bellows-like bellows 744 is provided in a through-hole at the bottom of the container of the lifting rod 742, and the vertical movement of the lifting rod 742 is allowed while maintaining the airtightness in the processing chamber 728. is doing.
Although not shown, a shadow is provided above the periphery of the mounting table 730 to focus the plasma and maintain the plasma stably, and to protect the wafer periphery and the mounting table periphery from etching during etching. The ring is also provided to be movable up and down.

  In addition, a cylindrical dome-shaped chamber 746 having a cylindrical body made of, for example, quartz or the like is provided in an airtight manner through a sealing member 748 such as an O-ring at the ceiling opening of the processing chamber 728. A high frequency coil 750 for inductively coupled plasma wound about ten or more turns is provided around the cylindrical chamber 746, and this high frequency coil 750 is inductively coupled at 450 kHz to 60 MHz, for example, via a matching circuit 752. It is connected to a high frequency power source 754 for plasma.

A gate valve 756 that is opened and closed when the wafer W is loaded / unloaded is provided on the upper side wall of the processing chamber 728. A gas supply means 757 is disposed along the circumferential direction between the ceiling opening of the processing chamber 728 and the dome-shaped chamber 746, and the gas supply means 757 has an annular groove 759. For example, about 20 gas injection holes 758 are formed, and the gas injection holes 758 are formed into the dome-shaped chamber 746 at a predetermined angle, for example, an angle of 20 to 60 °. A process gas such as a controlled plasma gas, for example, H ₂ , Ar, He, O ₂ , N ₂ gas and combinations thereof can be supplied into the process chamber 728.

An opening 762 having a large diameter of about 210 mm is formed at a substantially central portion of the bottom portion 760 of the processing chamber 728 with respect to an inner diameter of the processing chamber 728 of about 362 mm. A large-diameter exhaust pipe line 764 that extends substantially linearly downward (vertically) to the opening 762 is airtightly connected through a seal member 766 such as an O-ring, and exhaust conductance is reduced. Make it as large as possible.
Specifically, the exhaust pipe 764 is connected to an upper pipe 764A connected to the bottom 760 and a pipe diameter adjusting pipe 764B whose diameter is sequentially reduced to adjust the pipe diameter at the lower end. And the lower pipe 764C. Sealing members 765 and 768 such as O-rings are interposed at the joint portions of the pipes 764B and 764C, respectively, to maintain airtightness. A vacuum pump 798 is connected to the lower end of the lower pipe 764C, and a downstream exhaust pipe is connected to an exhaust flange 799 provided on the side of the vacuum pump 798 via a seal member 770 such as an O-ring. 772 is connected.

In addition, a mounting table support column 774 made of, for example, aluminum for supporting the mounting table 730 is provided coaxially at substantially the center of the upper pipe 764A of the exhaust pipe 764. Specifically, the mounting table support column 774 includes an upper hollow pipe member 774A and a lower hollow pipe member 774B that is airtightly joined to the lower end portion of the lower end portion via a seal member 776 such as an O-ring. The lower surface of the mounting table 730 is hermetically joined to the upper end of the hollow pipe member 774A to support the mounting table 730.
In this way, the lower hollow pipe member 774B and the outer upper pipe 764A are formed in a double pipe structure, and the exhaust gas flows down through the donut-shaped space between the two members. ing. A plurality of, in the illustrated example, four mounting plates 778 are provided at substantially equal intervals so as to connect the outer peripheral wall of the lower hollow pipe member 774B and the inner peripheral wall of the upper pipe 764A. The entire load of the mounting table 730 and the mounting table support column 774 is supported.

These mounting plates 778 are provided along the flow direction (vertical direction) of the exhaust gas so as to suppress the exhaust resistance as much as possible.
And the lower end of the lower hollow pipe member 774B of the mounting table support column 774 described above is a hollow line take-out pipe provided across the inside so as to penetrate the upper pipe 764A in the lateral direction and perpendicular to the gas flow direction. 780 are joined to each other in communication with each other. The line take-out tube 780 also receives the load of the mounting table 730 and the mounting table support column 774. The lower end of the mounting plate 778 is joined to the upper end portion of the outer peripheral wall of the line take-out pipe 780. If the strength is set so high that the line take-out pipe 780 can sufficiently receive the load, the attachment of the attachment plate 778 may be omitted.

  Further, a seal member 782 such as an O-ring is interposed in a portion where the line take-out pipe 780 penetrates the upper pipe 764A, and the air tightness in the exhaust pipe 764 is maintained. Further, the inside of the line take-out pipe 780 and the inside of the mounting table support column 774 are connected to the resistance heater 732 as a power supply line in the line take-out pipe 780 so as to communicate with the outside air. The heater wire 784 and the high-frequency wire 786 connected to the bias electrode 734 are inserted. The other end of the heater line 784 is connected to a heater power supply (not shown), and the other end of the high-frequency line 786 is a bias that outputs a high frequency for bias of 13.56 MHz, for example, via a matching circuit 788. It is connected to a high frequency power source 790 for use.

In addition, a cooling jacket 792 for preventing thermal damage of the seal member 776 provided here is provided at the joint between the upper hollow pipe member 774A and the lower hollow pipe member 774B of the mounting table support column 774. The refrigerant circulation path 794 for allowing the refrigerant to flow through the cooling jacket 792 is also inserted into the mounting table support column 774 and the line take-out pipe 780.
The lower pipe 764C of the exhaust pipe line 764 is provided with a flow path adjustment valve 796 made up of a three-position gate valve, and the flow path area is adjusted including the fully open state and the fully closed state of the exhaust pipe line 764. It has come to be able to do. As the flow path adjustment valve 796, a butterfly valve or the like that can arbitrarily adjust the flow path area may be used instead of the gate valve.

In addition, a vacuum pump 798 made of, for example, a turbo molecular pump or the like is directly interposed in the lower pipe 764C immediately below the flow path adjusting valve 796. In this case, the suction port 798A of the vacuum pump 798 is arranged so as to be orthogonal to the flow of the exhaust gas so as to minimize the exhaust resistance. In the figure, reference numeral 781 denotes a quartz focus ring for focusing so that plasma is uniformly formed on the entire surface of the object to be processed. The focus ring 78 has a plurality of holes on the circumference that expose the WDC detection electrodes embedded in the periphery of the mounting table.
In addition, the measurement main body 10 of the particle measuring means 8 described in the previous embodiment is provided in the lower pipe 764C and the downstream exhaust pipe 772, and the control / processing section 12 and the cleaning end point determining means 14 are further provided. May be.

<Fourth Modification>
Next, a case where the present invention is applied to a processing apparatus for forming a tungsten (W) film by thermal CVD using WF ₆ gas, H ₂ gas, SiH ₄ gas, Ar gas, and N ₂ gas will be described.
11 is a view showing a fourth modification of the processing apparatus of the present invention, FIG. 12 is a cross-sectional view showing the inside of the processing apparatus shown in FIG. 11, FIG. 13 is an exploded perspective view of the gas introduction section, and FIG. It is an expanded sectional view showing the gas introduction part of a part. This processing apparatus is substantially the same as the apparatus disclosed in Japanese Patent Laid-Open No. 2001-322847 except that a particle measuring unit and a cleaning end point determining unit are provided.

First, FIG. 11A shows a front view of the processing apparatus, and FIG. 11B shows a side view thereof.
In this processing apparatus 200, a tungsten film is formed on a semiconductor wafer W that is an object to be processed using H ₂ , SiH ₄ gas, Ar gas, N ₂ gas, and WF ₆ gas. As shown in FIGS. 11A and 11B, the processing apparatus 200 has a main body 202, and a lamp unit 204 is provided below the main body 202. Two upper exhaust pipes 206 communicating with an exhaust passage, which will be described later, are provided on the upper part of the main body 202, and these two exhaust pipes are connected to the main body 202 via a collective exhaust pipe portion 207 where the two join together. A lower exhaust pipe 208 connected to the upper exhaust pipe 206 via an exhaust passage which will be described later is provided in the lower part. The lower exhaust pipe 208 is a corner portion on the left side of the front portion of the main body 202 and is provided at a position retracted from the lamp unit 204.

  As shown in FIG. 12, the main body 202 has a processing chamber 210 formed in a bottomed cylindrical shape, for example, by aluminum or the like, and a lid 212 is provided thereon. A cylindrical shield base 214 is erected from the bottom of the processing chamber 210 in the processing chamber 210. An annular base ring 216 is disposed in the opening above the shield base 214, and an annular attachment 218 is supported on the inner peripheral side of the base ring 216, and a protrusion that protrudes to the inner peripheral edge of the attachment 218. A mounting table 220 on which the wafer W is mounted is provided. The lid 212 is provided with a shower head unit 222 to be described later at a position facing the wafer W mounted on the mounting table 220.

In the space surrounded by the mounting table 220, the attachment 218, the base ring 216, and the shield base 214, a cylindrical reflector 224 is erected from the bottom of the processing chamber 210. A slit portion is provided (one of them is shown in FIG. 11), and lift pins 226 for lifting the wafer W from the mounting table 220 are disposed in the slit portion so as to be movable up and down. The lift pin 226 is supported by the push-up rod 242 via an annular holding member 228 and a joint 230 provided outside the reflector 224, and the push-up rod 242 is connected to the actuator 244. The lift pins 226 are made of a material that transmits heat rays, for example, quartz. Further, a support member 246 is provided integrally with the lift pin 226, and the support member 246 passes through the attachment 218 and supports an annular clamp ring 248 provided thereabove. The clamp ring 248 is made of a carbon-based member such as amorphous carbon that easily absorbs heat rays, or ceramics such as Al ₂ O ₃ , AlN, and black AlN.

  With this configuration, the lift pin 226 and the clamp ring 248 move up and down integrally when the actuator 244 moves up and down the push-up bar 242. When delivering the wafer W, the lift pins 226 and the clamp ring 248 are raised until the lift pins 226 protrude from the mounting table 220 by a predetermined length, and the wafer W supported on the lift pins 226 is mounted on the mounting table 220. In doing so, the lift pins 226 are inserted into the mounting table 220 and lowered to a position where the clamp ring 248 contacts and holds the wafer W (see FIG. 11).

  In the space surrounded by the mounting table 220, the attachment 218, the base ring 216, and the shield base 214, the purge gas from the purge gas supply mechanism 250 is formed at the bottom of the processing chamber 210, and this Supplied through eight channels 252a that are equally distributed in the lower portion inside the reflector 224 and communicate with the purge gas channel. The purge gas supplied in this way flows out from the gap between the mounting table 220 and the attachment 216 along the radially outward direction, so that the processing gas from the shower head unit 222 described later enters the back side of the mounting table 220. This prevents the film from being formed on the peripheral portion (bevel portion) and the back side of the wafer W.

  Furthermore, openings 254 are provided at a plurality of locations on the shield base 214. The openings 254 operate on the inner peripheral side of the opening 254 when the pressure difference between the inside and outside of the shield base 214 exceeds a certain level. A plurality of pressure adjusting mechanisms 256 for communication are provided. As a result, it is possible to prevent the pressure difference between the inside and outside of the shield base 214 from becoming excessive and causing the clamp ring 248 to flutter or to be damaged due to a large force acting on any member.

  An opening 258 surrounded by a reflector 224 is provided at the bottom of the processing chamber 210 immediately below the mounting table 220, and a transmission window 260 made of a heat ray transmitting material such as quartz is airtightly attached to the opening 258. ing. A sapphire coating is formed on the surface of the transmission window 260. The lamp unit 204 is provided below the transmission window 260. The lamp unit 204 includes a heating chamber 262, a rotating table 264 provided in the heating chamber 262, a lamp 266 attached to the rotating table 264, a bottom portion of the heating chamber 262, and a rotating shaft 268. And a rotation motor 270 for rotating the turntable 264. In addition, the lamp 270 has a reflecting portion that reflects the heat rays, and the heat rays radiated from the respective lamps 270 are reflected directly or on the inner periphery of the reflector 224 to reach the lower surface of the mounting table 220 evenly. Are arranged as follows. With such a configuration, heat rays emitted from the lamp 266 are emitted to the lower surface of the mounting table 220 through the transmission window 260 by radiating heat rays from the lamp 266 while rotating the rotating table 264 by the rotary motor 270. The mounting table 220 can be heated evenly.

The above-described shower head portion 222 is fitted to a cylindrical shower base 272 formed so that an outer edge thereof is fitted to the upper portion of the lid 212, and an inner peripheral side upper portion of the shower base 272, and further to the upper portion thereof as described later. And a shower plate 278 attached to the lower portion of the shower base 272. As shown in FIGS. 12 and 13, the introduction plate 276 has a main gas flow path 280 formed in the center thereof, and a plurality of (only one is shown in FIG. 12) surrounding the main gas flow path 280. A reducing gas flow path 282 such as peripheral H ₂ gas or SiH ₄ gas is formed. Further, the shower plate 278 is provided with a large number of main gas discharge holes 284 having a diameter of 1 to 3 mm, for example, in a lattice shape or radially, at positions corresponding to the mounting table 220, the attachment 218, and the base ring 216. A peripheral H ₂ gas discharge hole 286 having a diameter of 1 to 3 mm is provided vertically at equal intervals or randomly on the circumference at the outermost part on the peripheral side of the shower plate 278. An annular refrigerant flow path 288 is provided below the shower plate 278, and the temperature of the shower plate 278 can be adjusted by flowing the refrigerant from the refrigerant supply mechanism 292 through the refrigerant supply pipe 290 through the refrigerant flow path 288. It has become. A spacer ring 294 is disposed on the outer periphery of the shower plate 278 and the shower base 272 so as to fill a gap between the shower plate 278 and the shower base 272 and the side wall of the processing chamber 210.

  A shower head portion 222 for introducing a processing gas is disposed in the shower head portion 222 of the processing chamber 210. The shower head portion 222 is configured to be surrounded by a shower base 272, a gas introduction plate 276 and a shower plate 278. The gas introduction part 274 for introducing the processing gas is connected to the upper side of the gas introduction plate 276 disposed at the lowermost end, and the gas introduction plate 276 is connected to the shower base 272. The interior of the shower head portion 222 includes a substantially annular partition 296 formed integrally with the shower base 272, a cylindrical partition 298 connected to the lower portion of the substantially annular partition 296, and the cylindrical partition. 298 and a shower plate 278, a plurality of main gas passage holes 300 are formed, and a covered cylindrical rectifying plate 302 is provided to be fitted and connected to an annular partition 296 and a shower plate. Yes.

The space in the shower head portion 222 includes a first space portion 304a substantially formed by a substantially annular partition wall 296, a cylindrical partition wall 298, and a rectifying plate 302, and the first space portion 304a. A second space 304b substantially formed by a cylindrical partition 298 and a rectifying plate 302 on the outside, and a substantially annular partition 296 formed substantially above the first space 304a. 3 space portions 304c and a fourth space portion 304d substantially formed by the rectifying plate 302 below the first space 304a. That is, the space in the shower head portion 222 includes a first space portion 304a formed at the center, a fourth space portion 304d formed below the first space portion 304a, and the first and fourth spaces. It is partitioned into a second space portion 303d formed outside the space portions 304a and 304d and a third space portion 304c formed above the first space portion 304a. The first space 304a communicates with the main gas passage hole 280 provided in the introduction plate 276 at the upper portion thereof, and the fourth space portion via the main gas passage hole 300 provided in the rectifying plate 302 at the lower portion thereof. It communicates with the space 304d. The fourth space 304 d communicates with a main gas discharge hole 284 provided in the shower plate 278. The third space 304 c communicates with a peripheral H ₂ gas flow path 282 provided in the introduction plate 276 at the center, and between the substantially annular partition 296 and the shower base 272 at the periphery. It communicates with the second space 304b through the formed peripheral H ₂ gas passage hole 306. The second space 304b communicates with the peripheral H ₂ gas discharge hole 286.

Accordingly, the gas supplied from the main gas flow path 280 reaches the fourth space portion 304d from the first space portion 304a through the main gas passage hole 300 provided in the rectifying plate 302, and the fourth space portion. A gas is discharged vertically from 304 d toward the wafer W through a main gas discharge hole 284 provided in the shower plate 278. Further, the gas supplied from the peripheral H ₂ gas flow path 282 reaches the second space 304b from the third space 304c through the peripheral H ₂ gas passage hole 306, and showers from the second space 304b. It is adapted to be discharged vertically toward the peripheral portion of the wafer W through the peripheral H ₂ gas discharge hole 286 provided in the plate 278.

Next, the gas introduction part 274 will be described.
In the concave portion at the center of the gas introduction portion 274 described above, a covered cylindrical flow straightening plate 314 fitted into the upper portion of the gas introduction plate 276, a lower plate 316, an intermediate plate 318, and an upper plate 340 are provided in the casing 342. It is accommodated by fitting inside. Then, as shown in FIG. 14, these plates and the casing 342 are fastened and fixed with bolts 346 through seal members 304 at necessary positions. In the upper part of the casing 342, there are a peripheral H ₂ gas inlet 350, a first main gas inlet 352 and a second main gas inlet 354 connected to a gas supply mechanism 348 described later.

FIG. 13 is a perspective view showing a structure inside the casing 342 in the gas introduction part 274 described above. The upper plate 340 includes a cavity 356 communicating with the peripheral H ₂ gas inlet 350 of the casing 342, a flow path 358 communicating with the first main gas inlet 352 of the casing 342, and a second main of the casing 342. A flow path 360 communicating with the gas introduction port 354 is provided, and peripheral H ₂ gas flow paths 362 are provided at five locations on the outer peripheral side of the cavity on the bottom surface of the cavity 356. The number of the flow paths 362 may be at least more than five as long as the number is optimal for improving gas uniformity. A flow path 358 communicating with the first main gas inlet 352 communicates with a groove 366 formed at the center of the middle plate 318 via a groove 364 provided in a semicircular portion on the outer circumferential side of the middle plate 318. In the groove 366, a plurality of vertical grooves are formed in a protruding portion 367 protruding so that gas can be easily mixed, and are continuously communicated with the grooves 366 and 372 of the middle plate 318 and the lower plate 316.

The flow path 360 communicating with the second main gas introduction port 354 passes through a groove 370 provided in a semicircular portion on the outer peripheral side of the lower plate 316 via a flow path 368 provided in the middle plate 318. The groove 372 communicates with the groove 372 formed at the center of the lower plate 316, and in the groove 372, a plurality of vertical grooves are formed in the protruding portion 316A protruding so as to be easily mixed with the gas. It communicates with 314 spaces. This space communicates with the main gas flow path 280 via a space 371 formed by the gas introducing plate 276 and the rectifying plate 314 through the opening 374 of the rectifying plate 314. With such a configuration, H ₂ gas, WF ₆ gas, and the like are mixed in the groove 372, and this mixed gas is supplied from the shower head unit 222 into the processing chamber 210 via the main gas flow path 280. Yes. On the other hand, the peripheral H ₂ gas flow path 362 is formed so as to surround the main gas flow path 280 in the introduction plate 276 via the flow path 376 provided in the middle plate 318 and the flow path 378 provided in the lower plate 316. Each communicates with a peripheral H ₂ gas flow path 282 provided at each location.
The peripheral H ₂ gas is discharged into the third space 304C, supplied through the second space 704b into the processing chamber through the gas discharge hole 286.

The structure of the gas introduction part 274 in FIG. 14 is a structure in which the upper plate described in FIGS. 12 and 13 has no cavity and no peripheral H ₂ gas is supplied.
In the gas introduction part 274, H ₂ , SiH ₄ , Ar gas or the like is supplied to the first main gas introduction port 352 and the second main gas introduction port 354. Thereafter, the flow and mixing are performed in the same manner as described with reference to FIG. 13 and supplied from the main gas flow path 280 into the shower head 222. Further, ClF ₃ gas supplied to the ClF ₃ gas inlet 350 for the cleaning gas through the cleaning gas passage 362 formed in the center of the upper plate 340, the groove and the lower projecting portion 318A of the middle plate 318 plate 316 Is supplied into the shower head 222 via the gas flow path 28 through the groove of the convex portion 316A.

Then, the first and second main gases supplied to the main gas flow path 280 are mixed, and the first space portion 204a in the shower head portion 222 is passed through the main gas passage hole 300 of the rectifying plate 302. 4 is diffused in the space portion 304d and is uniformly discharged from the main gas discharge hole 284 toward the wafer W. In addition, a cleaning gas ClF ₃ gas for removing an unnecessary film formed in the processing chamber is supplied to the cleaning gas flow path 280, and the first space in the shower head unit 222 is similar to the main gas. An unnecessary film adhered to the inside of the processing chamber is removed by being diffused from the portion 304a through the main gas passage hole 300 of the rectifying plate 302 in the fourth space 304d and discharged from the main gas discharge hole 284 toward the wafer W. To do.
The above embodiment is a gas introducing portion when H ₂ gas is not flowed from the periphery, and a W film can be formed in a processing chamber having this configuration.

As described above, the main gas discharge holes 284 and the peripheral H ₂ gas discharge holes 286 are separately supplied with gas, so that gases having different compositions can be discharged.
The gas supply mechanism 348 described above has a ClF ₃ gas supply source 400, a WF ₆ gas supply source 402, an Ar gas supply source 404, an H ₂ gas supply source 406, an N ₂ gas supply source 408, and an SiH ₄ gas supply source 410. is doing. A gas line 412 is connected to the ClF ₃ gas supply source 400, and the gas line 412 is a first main gas provided in the gas introduction unit 274 via a mass flow controller 414 and opening / closing valves 416 and 418 before and after the mass flow controller 414. The inlet 352 is connected. A gas line 420 is connected to the WF ₆ gas supply source 402, and the gas line 420 is connected to a first gas inlet 274 via a mass flow controller 422 and front and rear valves 424 and 426. The main gas inlet 352 is connected. A gas line 428 is connected to the Ar gas supply source 404, and the gas line 428 is connected to a first main unit 274 provided in the gas introduction unit 274 via a mass flow controller 430 and front and rear valves 432 and 434. The gas inlet 352 is connected.

Gas lines 436 and 438 are connected to the H ₂ gas supply source 406, and the gas line 436 is connected to the peripheral H ₂ gas inlet 350 through the mass flow controller 440 and front and rear opening / closing valves 442 and 444. The gas line 438 is connected to the second main gas inlet 354 via the mass flow controller 446 and the opening / closing valves 448 and 450 before and after the mass flow controller 446. A gas line 452 is connected to the N ₂ gas supply source 408, and this gas line 452 is connected to the second main gas introduction of the gas introduction unit 274 via the mass flow controller 454 and front and rear valves 456 and 458. Connected to the mouth 354. A gas line 460 is connected to the SiH ₄ gas supply source 410, and the gas line 460 is connected to the second main gas introduction of the gas introduction unit 274 via the mass flow controller 462 and the opening / closing valves 464 and 466 before and after the mass flow controller 462. Connected to the mouth 354.

  On the other hand, as shown in FIG. 12, between the shield base 214 and the side wall of the processing chamber 210, an annular baffle plate 500 provided with an opening 500a over the entire circumference is attached. The baffle plate 500 vertically partitions a space formed between the shield base 214 and the side wall of the processing chamber 210. An annular space portion 502 formed below the baffle plate 500 is provided on the outer periphery of the space portion 502, and exhaust spaces 505 and 506 formed at lower positions that are diagonal to the processing chamber 210 are provided in communication with each other. It has been. One exhaust space, for example, 564, communicates with the side wall of the processing chamber 210 and one end of an exhaust passage 507 provided in the lid 212, and the upper exhaust pipe 206 is connected to the other end of the exhaust passage 507. Is connected.

  The upper exhaust pipe 206 is connected to the upper end of an exhaust passage 507 provided through the lid 212 and the side wall of the processing chamber 210 at the other corner of the processing chamber 210 and the exhaust pipe 207. An exhaust mechanism 510 having a vacuum pump is connected to the lower end of the path via a lower exhaust pipe 208. Further, the vicinity of the other exhaust space 506 has a structure similar to this. That is, the two upper exhaust pipes 206 connected to the two opposite corners of the processing chamber 210 merge into one exhaust flow path at the other corner of the processing chamber 210, and this exhaust flow path Is connected to an exhaust mechanism 510 through a single lower exhaust pipe 208 provided below the processing chamber. Then, by operating the exhaust mechanism 510, the atmosphere in the processing chamber 210 flows downward from the respective openings 500a of the baffle plate 500 to reach the exhaust spaces 502 and 504, and an exhaust gas (not shown) provided on the side wall of the chamber. The gas is exhausted upward via the flow path, and then gathers from the upper exhaust pipe 206 to the lower exhaust pipe 208 via the exhaust flow path (not shown) and exhausted therefrom.

  The measuring body 10 of the particle measuring means 8 described above is provided in the middle of the lower exhaust pipe 208 of the apparatus thus formed or in the middle of the upper exhaust pipe 206, and the cleaning end point determining means 14 is further provided. (See FIG. 1) may be provided. The cleaning end point determination means 14 may be anywhere as long as it is an exhaust line, but preferably an exhaust line portion closer to the processing chamber.

Next, an example of a tungsten film forming process performed using the processing apparatus and an example of process conditions at that time will be described.
First, in step 1, the processing chamber 210 is evacuated to a predetermined pressure, and then in step 2, the mounting table 220 is maintained at a predetermined temperature. Next, in steps 3 and 4, SiH ₄ gas or the like is allowed to flow so that the processes of initiation (1) and initiation (2) are sequentially performed to form Si on the wafer. At this time, SiH ₄ were supplied to such a low partial pressure conditions in the initiation (1), supplying SiH ₄ so that a high partial pressure conditions in the initiation (2). This initiation step can improve the embedment of the W film and suppress abnormal growth. A good effect is high when heated in this step. Next, purging is performed in step 5 to wipe out the previously introduced gas. Next, preflow is performed for a few seconds for the first time with a slight flow of WF ₆ in step 6, and nucleation is performed in step 7 to form tungsten crystal nuclei.

Next, in step 8, a larger amount of WF ₆ gas than that in the nucleation step is supplied to deposit a tungsten film with a predetermined thickness around the crystal nucleus. When the deposition process of the tungsten film is completed, a purge process is performed in step 9 to sweep out the gas flowed during the film formation. Then, in step 10, exhaust processing is performed to complete the tungsten film forming process.
The process conditions of each step of the film forming process are as follows.
WF ₆ gas: 5-200sccm
Ar gas: 500 to 6000 sccm
SiH ₄ gas: 1 to 300 sccm
H ₂ gas: 200 to 4000 sccm
N ₂ gas: 0 to 3000 sccm
Backside gas (Ar): 1000 to 5000 sccm
Pressure: 1-100 Torr (133.3-13330 Pa)
Temperature: 350-500 ° C
Process time: 2 to 120 sec
Alternatively, the nucleation film may be formed by alternately supplying a gas containing WF ₆ and a gas containing SiH ₄ .

In the present embodiment, the WSi film has been described as an example of the unnecessary film to be removed by the cleaning process. However, the present invention is not limited to this, and the cleaning process method of the present invention can be applied to any film type. Can do. For example, the present invention can be applied to a cleaning process for a film such as Ti, W, WN, TiN, Ta, TaOx, SiO ₂ , SiN, SiON, TaN, HfO ₂ , ZrO ₂ , and PaO ₃ . Further, the cleaning gas is not limited to ClF ₃ gas, and other cleaning gases such as NF ₃ , ClF, and HF can be applied to the present invention. It can also be applied to plasma cleaning endpoints. As the plasma source, it can be applied to plasma processing apparatuses such as capacitive electrostatic type (parallel plate), ICP, helicon wave, and microwave (radical line slot antenna type). Here, the semiconductor wafer has been described as an example of the object to be processed. However, the present invention is not limited to this, and the cleaning method of the present invention can be easily applied to a glass substrate, an LCD substrate, a compound semiconductor substrate, and the like. .

<Continuous film formation of titanium film and titanium nitride film>
Next, continuous film formation of a titanium film and a titanium nitride film will be described as a related invention of the present invention with reference to FIGS. This technique is related to the technique disclosed in Japanese Patent Laid-Open No. 10-106974 previously proposed by the present applicant. FIG. 15 is a diagram showing a plasma film-forming apparatus, and FIG. 16 is a process diagram showing a film-forming process. In this method, a titanium film and a titanium nitride film are continuously formed on the surface of a substrate to be processed, for example, a semiconductor wafer.

First, a method for forming a titanium film will be described with reference to the flowchart of FIG.
First, evacuation is performed while purging the inside of the processing chamber with an inert gas (step S21).
Next, when the inside of the processing chamber reaches a desired degree of vacuum, it is maintained (step S22).
Through a vacuum load lock mechanism (not shown), the wafer is mounted on a mounting table in the processing chamber in a vacuum state (step S23).
Thereafter, while introducing a processing gas (for example, Ar gas, H ₂ gas) into the processing chamber, the wafer is preheated (the wafer is preheated to the same temperature as the film forming process before the processing) (step 24).

Next, the TiCl ₄ gas is not introduced into the chamber from the gas supply system, but flows through an exhaust line (evac line) provided in a bypass manner for a predetermined time to stabilize the flow rate, and then a switching valve (preflow valve) (not shown). ) Is operated and introduced into the processing chamber (step S25).
This is because the flow rate of TiCl ₄ gas is stabilized and then introduced into the processing chamber.
When the flow rate of the TiCl ₄ gas is stabilized in the step 25, the switching valve is switched, the TiCl ₄ gas is introduced into the processing chamber, and plasma discharge is started (step S26). At this time, a time lag until reaching the inside of the processing chamber occurs. However, even if the high-frequency power supply is turned on at the same time as switching the switching valve, the response of the high-frequency matching device is slow, so that plasma discharge is also delayed. Therefore, the time lag is offset by the delay of the matching response, and as a result, plasma discharge is started smoothly. However, if the length of the gas line is short and there is no time lag in the introduction of TiCl ₄ gas into the processing chamber, the response of the high-frequency matching device should be accelerated or the introduction of TiCl ₄ gas matched to the response of the high-frequency matching device. It is necessary to adjust the timing to do so.
With this plasma discharge, a Ti film is formed on the wafer (step S27). The supply of TiCl ₄ gas is stopped, and the plasma gas (Ar, H ₂ gas) is introduced into the chamber and the residue (film forming component) in the chamber is exhausted while being replaced with the plasma gas (step S28). ).

Next, NH ₃ gas is further introduced into the processing chamber, and the formed titanium film is pre-nitrided (step S29). Thereafter, the high-frequency power source is turned on to generate plasma, and the pre-nitrided titanium film is further nitrided with a nitriding gas (Ar, H ₂ , NH ₃ gas) (step S30). Thereafter, the plasma discharge is stopped, and subsequently, a nitriding gas is introduced, and the residue in the processing chamber is exhausted and removed (step S31). Next, the film-formed wafer is unloaded from the processing chamber (step S32).

The process conditions of the pre-nitridation process in step S29 described above are H ₂ gas flow rate of 500 to 4000 sccm, Ar gas flow rate of 280 to 3500 sccm, NH ₃ gas flow rate of 200 to 3000 sccm, preferably H ₂ gas flow rate of 1000. ~3000sccm, Ar gas flow rate 750~2250sccm, NH ₃ gas flow rate is 650～2100Sccm. The ratio of the NH ₃ gas flow rate to the total gas flow rate is 0.026 to 0.8, preferably 0.16 to 0.36. The ratio of the H ₂ flow rate is 0.07 to 0.9, preferably 0.18 to 0.68. The flow rate ratio of NH ₃ gas to H ₂ gas is 0.05 to 3, preferably 0.2 to 2. Further, the process condition of the nitriding process in step S30 is that plasma is generated at the same gas flow rate as in step S29, and the Ti film is plasma-nitrided. The Ti film forming conditions in step S27 are as follows: TiCl ₄ gas flow rate is 2 to 20 sccm, Ar gas flow rate is 500 to 10000 sccm, H ₂ gas flow rate is 500 to 10000 sccm, preferably TiCl ₄ gas flow rate is ₄ to 16 sccm. The Ar gas flow rate is 800-3200 sccm, and the H ₂ gas flow rate is 200-7500 sccm. The ratio of the TiCl ₄ gas flow rate to the total gas flow rate is 0.00017 to 0.02, preferably 0.00037 to 0.0057, and the ratio of the TiCl ₄ gas flow rate to the H ₂ gas is 0.0002 to 0.038, Preferably, a good quality titanium (Ti) film is formed by forming a film at a flow rate ratio of 0.00053 to 0.008.

Next, a method for forming a titanium nitride film will be described with reference to the flowchart of FIG.
First, exhausting is performed while purging the inside of the processing chamber with an inert gas (step S41). Next, the introduction of the inert gas is stopped, and when the inside of the processing chamber reaches a desired degree of vacuum, it is maintained (step S42). Through a vacuum load lock mechanism (not shown), the wafer is mounted on a mounting table in the processing chamber in a vacuum state (step S43).
Then, a processing gas other than TiCl ₄ gas (for example, N ₂ or NH ₃ gas) is introduced into the processing chamber so that the flow rate gradually increases (step S44). This is because the wafer may be warped if introduced so as to increase the gas flow rate of the processing gas rapidly into the processing chamber.
Thereafter, the wafer is preheated while introducing the processing gas (N ₂ , NH ₃ gas) into the processing chamber (the wafer is preheated up to the same temperature as the film forming process before processing) (step S45).

Next, while introducing the processing gas (N ₂ , NH ₃ gas) into the processing chamber, TiCl ₄ gas is temporarily introduced from the gas supply system into the chamber without being introduced into the chamber. line) for a predetermined time and the flow rate is stabilized, and then a switching valve (preflow valve) (not shown) is operated to introduce into the processing chamber (step S46). This is because the flow rate of TiCl ₄ gas is accurately stabilized and introduced into the processing chamber to form an accurate film thickness. In terms of forming the thin film more accurately, it is important because the film thickness varies due to the variation in the flow rate of the source gas.
A TiN film is formed on the wafer in this gas atmosphere (step S47). When the TiN film is formed to a desired film thickness, the supply of NH ₃ and TiCl ₄ gas is stopped, and the N ₂ gas is introduced into the chamber, and the residue in the chamber (film forming component) Is purged and exhausted (step S48).

Next, with the N ₂ gas introduced into the processing chamber, NH ₃ gas is further introduced to further nitride the TiN film (step S49). This is done in order to remove by reduction nitriding by NH ₃ chlorine component TiN film which is formed. Then, the introduction of the NH ₃ gas is stopped, the N ₂ gas is kept introduced into the processing chamber, and the residue in the processing chamber is exhausted and removed (step S50). Next, the wafer is unloaded from the processing chamber (step S51).
The process conditions of the TiN film forming process in step S47 are TiCl ₄ gas flow rate of 10 to 100 sccm, NH ₃ gas flow rate of 20 to 2000 sccm, and N ₂ gas flow rate of 500 to 12220 sccm, preferably TiCl _4. The gas flow rate is 25-60 sccm, the NH ₃ gas flow rate is 100-1000 sccm, and the N ₂ gas flow rate is 500-6000 sccm. The ratio of TiCl ₄ gas flow rate to total gas flow rate is 0.000087 to 0.16, preferably 0.0036 to 0.09, and the ratio of TiCl ₄ gas flow rate to NH ₃ gas is 0.005 to 5. Yes, preferably 0.025 to 0.6. Further, the nitriding process condition in step S49 is that the NH ₃ gas flow rate ratio with respect to the total gas flow rate is 0.0016 to 0.8, preferably 0.016 to 0.66. Thus, a good TiN film is formed.

Next, a specific example using a plasma film forming apparatus as shown in FIG. 15 will be described.
In this plasma film forming apparatus, a resistance heater (not shown) is embedded in the mounting table 202 provided in the processing chamber 201. The resistance heater heats the wafer W to a predetermined process temperature, for example, about 400 to 700 ° C., and includes, for example, Ar gas as a film forming process gas, for example, H ₂ gas, or SiH ₄ gas and Ti as a reducing gas. A predetermined amount of gas is introduced from the shower head unit 204 into the processing chamber 201, a high frequency voltage of 450 kHz to 60 MHz is applied to the shower head unit 204, plasma is generated, and a titanium film is formed. For example, as a gas containing titanium, there are TiCl ₄ , TiI ₄ , TiBr ₄ , and organic Ti such as Ti (C ₂ H ₅ ) ₃ gas.

The process pressure at this time is 0.5 to 10 Torr, preferably 1 to 5 Torr. Under this condition, as shown in FIG. 16A, a titanium film 303 is selectively deposited on the conductor (substrate) 301 exposed at the bottom of the contact hole 302 opened in the insulating layer 306. . In this case, TiSi ₂ is formed in a self-aligned manner by reacting with Si on the substrate at the same time as Ti is formed. The thickness of the titanium film 303 is, for example, 5 to 50 nm, preferably 10 to 30 nm.
After the titanium film forming process is completed in this way, a titanium nitriding process is then performed on the substrate 301 at the same mounting position. First, after the supply of the processing gas for forming the titanium film is stopped, the processing gas atmosphere in the processing chamber 201 is exhausted while supplying Ar and H ₂ gases. Next, as a gas for plasma nitriding, a gas in which Ar gas, H ₂ gas and at least one of N ₂ , NH ₃ , and MMH (monomethyl drazine) gas are mixed, or each gas is individually supplied from the shower head unit 204. The material is supplied into the processing chamber 201 and mixed inside the chamber. This nitriding gas is introduced to make the inside of the processing chamber 201 a nitriding gas atmosphere. Next, a high-frequency voltage of 450 kHz to 60 MHz is applied from the high-frequency power source 205 to the shower head unit 204 serving as the upper electrode through the matching box 206 to generate nitriding plasma in the chamber.

Thus, the surface of the titanium film 303 is nitrided to form a nitride film 304 as shown in FIG. Further, even if a mixed gas of H ₂ + N ₂ or N ₂ + NH ₃ , H ₂ + NH ₃ is supplied, nitriding can be performed. More preferred is Ar + H ₂ + NH ₃ . In this case, the entire titanium film may be nitrided.
As the nitriding conditions at this time, the supply amount of each gas is about H ₂ : 250 to 3000 sccm, N ₂ : 50 to 1000 sccm, NH ₃ : 50 to 1000 sccm, MMH: about 1 to 100 sccm. The process pressure is about 0.5 to 10 Torr, preferably 1 to 5 Torr, and the process temperature is about 350 to 700 ° C. Moreover, high frequency electric power is 100-2000W, Preferably it is 500-1000W. The flow rates of H ₂ gas, N ₂ gas, NH ₃ gas, and MMH gas may be selected as appropriate, and are not limited to the above flow rates.

This nitriding step improves the adhesion between the Ti film and the TiN film. That is, an unreacted product such as TiCl _{4 in the} Ti film and on the Ti film surface is reduced to nitride the Ti film. It is also possible to suppress the so TiCl ₄ is film forming gas when forming a TiN film after the deposition of the Ti film etches the Ti film.
When the titanium nitriding process is completed in this way, the substrate 301 is moved into another film forming apparatus that is previously maintained in a vacuum state, and a conventionally known processing method is used in the film forming apparatus. Then, a film forming process for forming a titanium nitride film as shown in FIG. A titanium nitride film 305 functioning as a barrier metal layer is formed by CVD on the inner wall surface of the contact hole 302 and the entire upper surface of the insulating layer 306.

As the processing gas at this time, it is possible to use for example TiCl _4, NH ₃ and _{N 2.} The process temperature is about 400 to 600 ° C., and the process pressure is about 0.1 to 10 Torr, preferably 0.5 to 5 Torr. TiN can also be formed by alternately flowing TiCl ₄ gas and NH ₃ gas. According to this, the concentration of chlorine impurities is further reduced, and a highly barrier film is formed.
When this titanium nitride film forming process is completed, the processed substrate 301 is taken out of the film forming apparatus, and then tungsten, aluminum, copper, etc. are placed in the contact hole 302 as shown in FIG. The conductive material 307 is embedded.

As described above, when nitriding the surface of the titanium film 303, plasma is generated in a mixed gas atmosphere of Ar gas, H ₂ gas, at least one of N ₂ gas, NH ₃ gas, and MMH (monomethylhydrazine) gas. Since the Ti film is formed and the surface of the Ti film is nitrided, the adhesion with the TiN film is improved, and peeling from the substrate can be suppressed. In the conventional method using only conventional N ₂ gas or only NH ₃ gas, a large amount of nitrogen radicals having high nitriding ability are generated, and the Ti film surface and TiClx by-product in the film are not reduced. Ti is prevented from being nitrided, adhesion is lowered, and peeling occurs.

However, as a result of performing plasma treatment using the above-described mixed gas of Ar gas and H ₂ gas and at least one of N ₂ gas, NH ₃ gas, and MMH (monomethylhydrazine) gas, active hydrogen atoms are converted into a Ti film. The TiClx by-product in the surface and the film is reduced, Cl is removed, the active Ti and the active N radicals react, and the Ti film surface is effectively nitrided, thereby adhering to the TiN film. Becomes better. For the verification, the applicant actually performed the titanium film forming process and the nitriding process described above to form a TiN film as a barrier metal, and conducted a scratch test. However, the film was not peeled off from the substrate. It was not confirmed.

Further, when the plasma treatment is performed using the mixed gas of Ar gas and H ₂ gas and at least one of N ₂ gas, NH ₃ gas and MMH gas, the result is that the contact resistance is greatly reduced. can get. The reason for this is that the TiCl ₄ raw material remaining in the titanium film is strongly reduced by H ₂ gas to extract Cl, and degassing from the bi-product removes it as a gas such as Cl ₂ and HCl. This is because chlorine (Cl) that causes an increase in resistance does not remain in the film and on the film surface.
As described above, since the nitriding treatment of the surface of the titanium film is performed by plasma treatment in a mixed gas atmosphere of Ar gas, H ₂ gas, and at least one of N ₂ gas, NH ₃ gas, and MMH gas, contact resistance Further, since a stable nitride is also formed in the bi-product in the chamber formed during the titanium film formation, it can be peeled off to prevent generation of particles.

Here, the presence / absence of each gas or the change in the frequency (%) of the number of chips when the flow rate is changed is evaluated, and the evaluation result will be described.
19A to 19D are diagrams showing the presence or absence of each gas or the frequency (%) of the number of chips when the flow rate is changed. Here, the frequency of the number of chips is shown as a resistance value, but is a ratio of the chip within an arbitrary resistance value range. 26A shows the relationship between the NH ₃ gas ratio to the total gas and the frequency of the number of chips, and FIG. 26B shows the relationship between the NH ₃ gas ratio to the H ₂ gas and the frequency of the number of chips. It is.
FIG. 19A shows the frequency of the number of chips when the flow rate of H ₂ gas is changed using H ₂ gas and N ₂ gas without using NH ₃ gas. FIG. 19B shows the frequency of the number of chips when the flow rate of NH ₃ gas is changed using H ₂ gas and NH ₃ gas without using N ₂ gas, and FIG. 17C and FIG. D) shows the frequency of the number of chips when N ₂ gas, H ₂ gas and NH ₃ gas are used together and the flow rate of NH ₃ gas is changed. In FIG. 17C, the N ₂ gas is 50 sccm, and in FIG. 19D, the N ₂ gas is 500 sccm. In addition, Ar gas is used as the plasma gas.

In the example shown in FIG. 19A, the frequency of the number of chips increases as the flow rate of H ₂ gas increases. However, it is necessary to flow H ₂ gas in a large amount, for example, about 2000 sccm. In the example shown in FIG. 19B, the frequency of the number of chips increases as the flow rate of NH ₃ gas increases, but the degree of increase is low. When the NH ₃ gas is about 400 sccm, the frequency of the number of chips is about 90% and does not reach 100%. In contrast, in the example shown in FIG. 19C, the flow rate of N ₂ gas is 50 sccm, and the frequency of the number of chips increases as the flow rate of NH ₃ gas increases. The degree of increase is high, NH ₃ gas is about 400 sccm, and the number of chips reaches about 100%. Further, in the example shown in FIG. 19D, the flow rate of N ₂ gas is set to a large value of 500 sccm, the flow rate of NH ₃ gas is 50 sccm or more, and the power of the chip is stably maintained at about 100%. ing.

  According to the cleaning method of the film forming apparatus of the third embodiment described above, the number of particles actually flowing in the exhaust system is measured. When the number of particles decreases through a peak and becomes less than a predetermined amount, it is determined as a just etch timing. Based on this determination, it is possible to appropriately set the endpoint for ending the cleaning process. Accordingly, excessive over-etching in the cleaning process can be prevented without being influenced by the cumulative number of objects to be processed that have been processed before the cleaning process. For this reason, not only can the lifetime of the structure in the chamber be shortened, but also wasteful consumption of the cleaning gas can be suppressed.

Here, a delivery mechanism for an object to be processed (for example, a wafer or a glass substrate) in the mounting table employed in the present embodiment will be described.
The conventional transfer mechanism as shown in FIG. 1 described above has a structure in which a plurality of push-up pins for supporting a wafer move vertically through the pin insertion holes of the mounting table. In this configuration, when the push-up pins move up and down for wafer transfer and pass through the pin insertion holes, if the sliding accuracy is poor or thermal deformation occurs, the pins slide in contact with the inner walls of the pin insertion holes. May generate particles. Generated particles enter the gas atmosphere near the wafer and adhere to the wafer surface during film formation, causing circuit pattern defects, or adhere to the back side of the wafer and transfer the particles to other chambers during wafer transfer. Cause it to be brought in. In some cases, the tip of the push-up pin may collide with the opening of the pin insertion hole and damage the push-up pin.

Further, when the wafer is moved up and down, there is vibration due to sliding of the push-up pin and the presence of gas (excluding due to the degree of vacuum of the processing chamber) existing in the space between the back surface of the wafer and the mounting surface of the mounting table. The wafer mounting position on the mounting surface may be shifted or the wafer may fall from the push-up pins.
Therefore, in the delivery mechanism employed in the present embodiment, a push-up pin is inserted into each of the plurality of pin insertion holes of the mounting table. The push-up pin is formed with a length that falls within the depth range of the pin insertion hole. The push-up members that push up the push-up pins from below (the direction along the pin insertion hole) are connected. By moving this push-up member (positioning drive pin) up and down with a predetermined stroke, the push-up pin moves up and down smoothly from the upper surface (wafer mounting surface) of the mounting table.

Specifically, as shown in FIGS. 20A and 20B, the push-up pin 311 is entirely formed of ceramics such as alumina or quartz, and a plurality of pin insertion holes provided in the mounting table 202. 312 is inserted. In this case, the outer diameter of the push-up pin 311 is slightly smaller than the inner diameter of the pin insertion hole, so that a slight gap 313 is formed. The pin insertion hole 312 communicates the space S 1 between the back surface of the wafer W and the top surface of the mounting table 96 and the space S 2 on the back surface side (downward) of the mounting table 202 via a gap 313.
The push-up pin 311 has a flat upper end surface, and a fitting hole 314 is formed at the lower end in a range not penetrating. In the fitting hole 314, the upper end portion of the positioning drive pin 315 is inserted and fixed. A lower end of the positioning drive pin 315 is fixed to the push-up member 316 so as to penetrate therethrough. The push-up member 316 is connected to an actuator 317A shown in FIG. A stopper 317 is provided below the positioning drive pin 315 for restricting ascent. The raising position of the push-up pin 311 may be defined by applying the stopper 317 to stop when raising.

  With such a configuration, as shown in FIG. 20A, when the push-up member 316 is lifted, the positioning drive pins 315 and the push-up pins 311 are lifted, and the wafer W is transferred to and from the transfer arm (not shown). Is called. On the other hand, as shown in FIG. 20 (B), when the push-up member 316 is driven downward, the upper surfaces of the positioning drive pins 315 and the push-up pins 311 are flat with or sink from the upper surfaces of the pin insertion holes 312 of the mounting table 202. The wafer W to be supported is placed on the upper surface of the mounting table 202. The wafer W is held by an electrostatic chuck mechanism (not shown) provided on the mounting table 202.

Next, FIG. 15 shows a configuration example of a processing apparatus equipped with the push-up pin configured as described above and its driving mechanism. The raising / lowering operation will be described with reference to this.
The processing chamber 201 is connected to a load lock chamber (not shown) via a gate valve, and both can be evacuated to maintain a vacuum state. Wafers are transferred between them by a transfer arm (not shown). In addition, a resistance heater (not shown) is embedded in the mounting table 202 on which the wafer W is mounted, and the wafer can be heated and stably maintained to a desired temperature.

  First, the inside of the load lock chamber and the processing chamber 201 is maintained at a high degree of vacuum. A wafer W to be processed is held by the transfer arm, and is transferred to a predetermined position in the processing chamber 201 through a gate valve and a transfer port opened from the load lock chamber. At this time, when the actuator 317A is driven to raise the push-up member 316 as shown in FIG. 20A, the positioning drive pin 315 rises from the standby position (lowermost position) to the delivery position (uppermost position). To do. The push-up pin 311 is pushed up so as to be pushed out from the pin insertion hole 312 when the positioning drive pin 315 is raised. The upper end of the push-up pin 311 pushes up the wafer W held by the transfer arm, and as a result, the wafer W is transferred from the transfer arm to the push-up pin 311. Thereafter, the transfer arm is retracted.

Then, when the actuator 317A is driven to lower the push-up member 316 as shown in FIG. 20B, the positioning drive pin 315 and the push-up pin 311 are lowered accordingly, and the push-up pin 311 moves to the pin insertion hole 312. Immerse completely. At this time, the wafer W is also lowered and placed on the upper surface (mounting surface) of the mounting table 202 and held by an electrostatic chuck mechanism (not shown). Thereafter, the wafer W is subjected to various process processes such as the Ti and TiN film forming processes and the nitriding process as described above.
Further, after the process is completed, the push-up member 316 is raised again. With this rise, the positioning drive pins 315 are pushed up, and the push-up pins 311 on which the wafer W is placed are raised. Then, the transfer arm is inserted below the wafer W in the lifted state, and the wafer W is transferred to the transfer arm by the lowering of the push-up pins 311. As the transfer arm is retracted, the wafer W is unloaded.

With such a configuration, the push-up pin 311 inserted into the pin insertion hole 312 smoothly moves up and down with a slight contact during the delivery, so that a collision that generates particles or damages the push-up pin is caused. And sliding can be prevented.
Further, since the space S1 between the back surface of the wafer W and the mounting surface of the mounting table 202 and the space S2 on the back surface side (downward) of the mounting table 202 communicate with each other through the gap 313, the wafer is lowered. At this time, the gas existing in the space S1 escapes to the space S2, and when the wafer W is lifted, it is generated when the space S1 is created from the state where the back surface of the wafer W and the mounting surface of the mounting table are in close contact with each other. It is possible to prevent the displacement of the mounting position and the wafer falling.

Next, FIG. 21 shows a cross-sectional configuration of a first modification of the above-described delivery mechanism. In the above-described delivery mechanism, the push-up pin 311 is supported by the upper end portion of the positioning drive pin 315. However, in this modification, a flange portion 315c is provided in the middle of the positioning drive pin 315, and the positioning drive pin 315 In this configuration, the push-up pin 311 is supported by the flange portion 315c. The other configuration is the same as the above-described delivery mechanism.
The positioning drive pin 315 has an outer diameter of the upper part 315 a that fits in the fitting hole 318 of the push-up pin 311 slightly smaller than the inner diameter of the fitting hole 318, and has a gap between the push-up pin 311 and the push-up pin 311. . The outer diameter of the flange portion 315 c of the positioning drive pin 315 is slightly smaller than the inner diameter of the pin insertion hole 312, and a gap 313 is provided between the flange portion 315 c and the inner wall of the pin insertion hole 312. Further, the outer diameter of the lower portion 315 b of the positioning drive pin 315 is smaller than the inner diameter of the pin insertion hole 312, and there is a gap between the lower portion 315 b and the inner wall of the pin insertion hole 312.

According to this configuration, in addition to the operation and effect of the above-described delivery mechanism, the push-up pin 311 is held substantially vertically in the fitting hole 318, so that the push-up pin 311 is prevented from being inclined during movement, and contact is made. The push-up pin 311 can be lifted and lowered smoothly.
Further, the reference position (lowering position) and delivery position (upward position) of the push-up pin 311 can be easily adjusted by adjusting the fixing position of the positioning drive pin 315 and the push-up member 316.
In this modification, the lower end portion 315 d of the positioning drive pin 315 is fixed to the push-up member 316 with a nut 320 or the like. However, if there is no high demand for positioning accuracy, the lower end portion 315d and the push-up member 316 may be slidably mounted within a certain range. With such a configuration, even when expansion and contraction due to heat occurs in the push-up member 316, it is possible to reduce the influence of vertical movement of the push-up pin 311. In this first modification as well, since the gap 313 is provided between the push-up pin 311 and the pin insertion hole 312, the gas passes through the gap 313 when moving up and down, and the positional deviation or the like on the mounting surface of the wafer W can be reduced. Dropping from the push-up pin 311 can be prevented.

Next, FIG. 22 shows a cross-sectional configuration of a second modification of the above-described delivery mechanism. In the second modification, a gap 319 is provided between the wall surface of the fitting hole 318 and the upper side surface of the positioning drive pin 315 fitted therein, and only the upper end portion is in a free state. ing. A plurality of push-up pins 311 are provided on the mounting table 202. The clearances 313 between these push-up pins 311 and the respective pin insertion holes 312 are equal, and these push-up pins 311 are lowered at the same speed even in a free state. The lower end portion of the positioning drive pin 315 is fixed to the push-up member 316 with a nut 320 or the like.
According to such a configuration, it is possible to obtain the same operation effect as the above-described delivery mechanism, and furthermore, since the push-up pin 311 and the positioning drive pin 319 are provided, the heat generated in the mounting table 202 is generated by the positioning drive pin 315. Therefore, it is possible to prevent thermal deformation or the like of the positioning drive pin 315.

Next, FIG. 23 shows a cross-sectional configuration of a third modification of the above-described delivery mechanism.
In the third modified example, the plurality of push-up pins 311 are formed short in a range not penetrating the pin insertion hole 312 formed in the mounting table 202. When the push-up pins 311 are lowered, the push-up pins 311 are reliably pulled down by a stopper function.
As shown in FIG. 23, a bulging portion 321 protruding like a collar is formed at the upper end portion of the positioning drive pin 315. Further, a narrowed portion 322 is formed at the lowermost portion of the fitting hole 318 of the push-up pin 311. The maximum outer diameter dimension of the bulging part 321 is formed to be larger than the minimum inner diameter dimension of the constriction part 322, that is, the bulging part 321 does not have to be caught by the constriction part 322 and come out of the fitting hole 318. The bulging portion 321 and the constricted portion 322 are in a relationship of a male screw and a female screw, and the upper end portion of the positioning drive pin 315 is inserted into the fitting hole 318 by screwing the bulging portion 321. Note that the bulging portion 321 and the narrowed portion 322 are not only engaged by a screw shape, but, for example, a key groove is formed in the narrowed portion 322, and a key protruding portion (key groove and May be formed, fitted and rotated to be engaged. However, it is necessary to make the key groove have a two-layered structure so that the key protrusion does not come out easily, or to provide a stopper inside. The lower end portion of the positioning drive pin 315 is fixed to the push-up member 316 with a nut 320 or the like.

  According to such a configuration, when the positioning drive pin 315 is lowered and the push-up pin 311 is returned into the mounting table 202, the push-up pin 311 is provided with the narrow portion (or key groove) 322, so that the bulge It can be forcibly pulled down by engaging with the portion (or key protruding portion) 321. In addition, since a gap 319 is provided between the push-up pin 311 and the positioning drive pin 315, heat generated in the mounting table is hardly transmitted to the positioning drive pin 315, and thermal deformation of the positioning drive pin 315 is prevented. Can do. Furthermore, by providing the narrowed portion 322 at a position above the bottom of the fitting hole 318 by the length of the bulging portion 321, there is no play at the upper end of the positioning drive pin 315 with respect to the fitting hole 318, and the push-up pin 311. Can be pulled down the same.

Next, FIG. 24 shows a cross-sectional configuration of a fourth modification of the above-described delivery mechanism. In this modification, the stopper function of the push-up pin 311 is added to the configuration of FIG. 22 described above. That is, the flange portion 323 is provided in the opening portion of the pin insertion hole 312 of the mounting table 202 to function as a stopper when the push-up pin 311 is lowered (stored in the pin insertion hole 312). The lower end portion of the push-up pin 311 comes into contact with the flange portion 323. At this time, the upper surface of the upper end portion of the push-up pin 311 is configured to stop at the same surface as the mounting surface of the mounting table 202 or a position lower than the mounting surface.
With such a configuration, when the push-up pin 311 is locked and supported by the flange portion 323 when stored in the mounting table 202, the push-up pin 311 can always stop at an appropriate position. In addition, since a gap 319 is provided between the push-up pin 311 and the positioning drive pin 315, heat generated in the mounting table 202 is hardly transmitted to the positioning drive pin 315, and thermal deformation of the positioning drive pin 315 is prevented. be able to.

Next, FIG. 25 shows a cross-sectional configuration of a fifth modification of the above-described delivery mechanism. This modification is a configuration in which the positioning drive pin 315 and the push-up member 316 are separated by combining the configuration of the bulging portion and the constriction portion of FIG. 23 and the configuration of the flange portion of FIG. A pin support tray 324 is provided at a location where the push-up member 316 and the lower end portion of the positioning drive pin 315 come into contact with each other.
In this configuration, when the push-up member 316 is lifted by an actuator (not shown) or the like, the push-up member 316 comes into contact with the lower end portion of the positioning drive pin 315 and pushes up the positioning drive pin 315. Next, the upper end portion of the positioning drive pin 315 is raised, the push-up member 316 is brought into contact with the uppermost portion (bottom) of the fitting hole 318, and the push-up pin 311 is raised so as to be pushed out from the pin insertion hole 312. Then, when the push-up member 316 is raised and stopped, the push-up pins 311 are stopped at the wafer delivery position.

Further, when the push-up member 316 is lowered, they are integrally lowered by the weight of the positioning drive pin 315 and the push-up pin 311. Then, the push-up pin 311 is brought into contact with the collar portion 323 and locked, and the positioning drive pin 315 is lowered, and the bulging portion 321 of the positioning drive pin 315 is brought into contact with and locked to the narrowed portion 322. With the configuration of the fifth modified example, it is possible to obtain the operational effects having the third and fourth modified examples described above.
In the workpiece transfer mechanism described above, the push-up pin does not move up and down through the placement table, and the push-up pin having a length equal to or less than the thickness of the placement table is inserted into the pin insertion hole of the placement table. . The pin is supported so as to be movable in the direction along the pin insertion hole, that is, vertically, and the push-up pin is lifted and lowered smoothly by the positioning drive pin. Therefore, the generation of particles is suppressed, and damage to the push-up pin due to the collision of the tip of the push-up pin with the opening of the pin insertion hole is prevented. The space between the back surface of the wafer and the mounting surface of the mounting table and the space behind the mounting table are communicated by a gap between the pin insertion hole and the push-up pin, and the wafer is mounted on the mounting surface of the mounting table. The gas can be moved smoothly at the time of detachment, and the wafer can be prevented from being displaced or dropped. Further, it is possible to prevent the wafer from being displaced or dropped from the pins due to vibration generated by sliding between the mounting table and the push-up pins.

It is a figure which shows the structural example of the processing apparatus of this invention carrying a particle | grain measurement means. It is a top view which shows the positional relationship of the permeation | transmission window and exhaust port in a processing chamber. It is a figure which shows the attachment state of a particle | grain measurement means. It is a block configuration diagram showing a cleaning end point determination means. It is explanatory drawing for demonstrating the principle which determines the end point of a cleaning process. It is a figure which shows the result of having examined the correlation with the just etch time and increase / decrease in the number of particles. It is a flowchart which shows the determination process of an etching end point. It is a block diagram which shows the 1st modification of the processing apparatus of this invention. It is a block diagram which shows the 2nd modification of the processing apparatus of this invention. It is a block diagram which shows the 3rd modification of the processing apparatus of this invention. It is a figure which shows the 4th modification of the processing apparatus of this invention. It is sectional drawing which shows the inside of the processing apparatus shown in FIG. It is a disassembled perspective view which shows a gas introduction part. It is an expanded sectional view which shows the gas introduction part of a shower head part. It is a figure which shows a plasma film-forming apparatus. It is process drawing which shows the process of film-forming. It is a flowchart which shows the film-forming method of a titanium film. It is a flowchart which shows the film-forming method of a titanium nitride film. It is a figure which shows the frequency | count (%) of the number of chips when the presence or absence of each gas, or the flow volume is changed. It is a section lineblock diagram showing a delivery mechanism. It is a section lineblock diagram showing the 1st modification of a delivery mechanism. It is a section lineblock diagram showing the 2nd modification of a delivery mechanism. It is a section lineblock diagram showing the 3rd modification of a delivery mechanism. It is a section lineblock diagram showing the 4th modification of a delivery mechanism. It is a section lineblock diagram showing the 5th modification of a delivery mechanism. NH ₃ is a diagram illustrating a capital relationship between the number of gas ratio and the number of chips.

Explanation of symbols

2 CVD equipment (processing equipment)
4 treatment unit 6 exhaust system 8 particle measurement means 10 measurement body 14 cleaning end point determination means 16 treatment chamber 20 mounting table 32 heating lamp 40 shower head section (gas supply means)
DESCRIPTION OF SYMBOLS 70 Laser beam irradiation part 76 Scattered light detection part 80 Low particle number duration measurement part 81 Particle number judgment part 82 Just etch time determination part 84 Over etch period determination part 86 End point determination part 89 Control part W Semiconductor wafer (to-be-processed object)

Claims (8)

In the delivery mechanism used when delivering the object to be processed to the mounting table provided in the processing chamber made evacuated,
Between the inner wall of the pin insertion hole provided in the mounting table described above, it is inserted through a gap that allows gas to flow through the space on the mounting surface side and the space on the back surface side of the mounting table. And a plurality of push-up pins that are set to a length that falls within the depth range of the pin insertion hole and whose front end abuts against the back surface of the object to be processed,
A fitting hole formed by opening the lower end of each push pin,
A plurality of positioning drive pins whose upper ends are inserted into the fitting holes and support the push-up pins;
A push-up member that commonly supports the lower ends of the positioning drive pins;
An actuator for driving the push-up member up and down ,
The outer diameter of the upper portion of the positioning drive pin is larger than the inner diameter of the fitting hole so that there is a gap for suppressing heat transfer between the push-up pin and the positioning drive pin between the side wall of the fitting hole. And a flange portion is formed on the positioning drive pin to support a lower end portion of the push-up pin . 2. The delivery mechanism according to claim 1 , wherein the positioning drive pin is provided with a stopper for restricting the positioning drive pin from rising. The lower end of the positioning drive pin claim 1 Symbol placement of delivery mechanism, characterized in that it is fixed by the push nut can be adjusted in a fixed position relative to the member. In the delivery mechanism used when delivering the object to be processed to the mounting table provided in the processing chamber made evacuated,
Between the inner wall of the pin insertion hole provided in the mounting table described above, it is inserted through a gap that allows gas to flow through the space on the mounting surface side and the space on the back surface side of the mounting table. And a plurality of push-up pins that are set to a length that falls within the depth range of the pin insertion hole and whose front end abuts against the back surface of the object to be processed,
A fitting hole formed by opening the lower end of each push-up pin;
A plurality of positioning drive pins whose upper ends are inserted into the fitting holes and support the push-up pins;
A push-up member that commonly supports the lower ends of the positioning drive pins;
An actuator for driving the push-up member up and down,
The outer diameter of the upper portion of the positioning drive pin is larger than the inner diameter of the fitting hole so that there is a gap for suppressing heat transfer between the push-up pin and the positioning drive pin between the side wall of the fitting hole. Is set so as to be smaller, and is configured to support the push-up pin only by the upper end portion of the positioning drive pin. A constriction is provided at the lowermost part of the fitting hole, and the upper end of the positioning drive pin has a bulge protruding in a flange shape so that its maximum outer diameter is larger than the minimum inner diameter of the constriction. The delivery mechanism according to claim 4, wherein a delivery portion is provided. 6. The delivery mechanism according to claim 5, wherein the bulging portion and the constricted portion can be engaged and disengaged by screwing or by a key groove and a key protrusion. Wherein the lower opening portion of the pin insertion holes, as claimed in any one of claims 1 to 6, characterized in that the flange portion of the push-up pin functions as a stopper when descending is provided Delivery mechanism. A processing chamber made evacuable,
A mounting table for mounting a target object to be subjected to a predetermined process;
Gas supply means for supplying a necessary gas to the processing chamber;
An exhaust system for evacuating the atmosphere in the processing chamber with a vacuum pump;
Processing apparatus characterized by comprising a, a transfer mechanism as claimed in 1 through 7, whichever is one of claims used when passing the object to be processed with respect to the mounting table.

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