Patent Description:
With an increase in the variety of device manufacturing methods (processes) using exposure apparatuses, it is necessary to convey various types of substrates with high productivity (at high speed). The various types of substrates include, for example, a substrate with a large amount of warpage, a substrate having a reverse surface with low flatness, and a substrate having a reverse surface coated with a chemical agent or coating agent.

<CIT> and <CIT> propose techniques concerning the conveyance of substrates. <CIT> discloses a technique of conveying substrates with high productivity by changing drive parameters of the respective units of a conveying mechanism, the pressure (substrate chucking pressure) with which a substrate is chucked, and the like. <CIT> discloses a technique of conveying substrates with high productivity by using dual conveying paths for substrates.

None of the conventional techniques is a technique that can automatically determine (select), on the apparatus side, optimal drive parameters, a substrate chucking pressure, a conveying path, and the like for each process with respect to various types of substrates.

According to <CIT>, it is necessary to provide a unit for measuring the amount of warpage of a substrate or grasp the amount of warpage of a substrate in advance. In addition, according to <CIT>, drive parameters of the respective units of the conveying mechanism and a substrate chucking pressure are determined from the amount of warpage of a substrate, but there is no consideration to the state of the reverse surface of the substrate. On the other hand, the technique disclosed in <CIT> needs to provide two conveying paths (first and second conveying paths) in order to improve the productivity of substrate conveyance. <CIT> discloses a wafer loading transport system which is more stable against unscheduled events. <CIT> discloses a method of holding and conveying an object based on electrostatic attraction. Also <CIT> discloses a method of holding and conveying an object based on attraction.

The present invention provides a substrate processing apparatus advantageous in determining a conveying procedure when conveying substrates.

The present invention in its first aspect provides a substrate processing apparatus as specified in claims <NUM> to <NUM>.

The present invention in its second aspect provides an article manufacturing method as specified in claim <NUM>.

Further aspects of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

Note, the following embodiments are not intended to limit the scope of the claimed invention, which is defined by the appended claims only.

<FIG> is a schematic view showing the arrangement of an exposure apparatus <NUM> according to one aspect of the present invention. The exposure apparatus <NUM> is a lithography apparatus used in a photolithography process as a manufacturing process for a device, and processes substrates. In this embodiment, the exposure apparatus <NUM> is implemented as a substrate processing apparatus that forms patterns on substrates. The exposure apparatus <NUM> exposes a substrate via a mask (original) by a step-and-scan system or step-and-repeat system and transfers a mask pattern onto the substrate.

Note that the present invention does not limit the substrate processing apparatus to an exposure apparatus and may also be applied to an imprint apparatus and a drawing apparatus. In this case, the imprint apparatus brings an imprint material supplied onto a substrate into contact with a mold, and applies curing energy to the imprint material to form a pattern on the cured material onto which a mold pattern is transferred. The drawing apparatus forms a pattern (latent image pattern) on a substrate by drawing on the substrate with a charged particle beam (electron beam) or laser beam. In addition, the present invention can be applied to apparatuses configured to process substrates, such as various types of high-precision processing apparatuses and various types of high-precision measurement apparatuses.

The exposure apparatus <NUM> includes an illumination optical system <NUM> that illuminates a mask <NUM> with light from a light source <NUM>, a projection optical system <NUM>, a first drive unit <NUM>, a second drive unit <NUM>, a substrate stage <NUM>, a laser interferometer <NUM>, and a third drive unit <NUM>. The exposure apparatus <NUM> further includes an alignment measurement system <NUM>, a focus measurement system <NUM>, a main control unit <NUM>, an illumination system control unit <NUM>, a projection system control unit <NUM>, a stage control unit <NUM>, and a conveying unit <NUM>.

The light source <NUM> emits (outputs) light in a plurality of wavelength bands as exposure light. The illumination optical system <NUM> further includes a shaping optical system (not shown) and an optical integrator (not shown). The illumination optical system <NUM> further includes a light-shielding plate <NUM>, a half mirror <NUM>, and a photosensor <NUM>.

The light emitted from the light source <NUM> and entering the illumination optical system <NUM> is shaped into a predetermined shape via the shaping optical system. The light shaped by the shaping optical system enters the optical integrator. The optical integrator forms many secondary light sources for illuminating the mask <NUM> with a uniform illuminance distribution. The light-shielding plate <NUM> is arranged on the optical path of the illumination optical system <NUM> to form an arbitrary illumination region on the mask. The half mirror <NUM> is arranged on the optical path of the illumination optical system <NUM> to reflect (extract) part of light (exposure light) illuminating the mask <NUM>. The photosensor <NUM> is arranged on the optical path of light reflected by the half mirror <NUM> to detect the intensity (exposure energy) of the light. The illumination system control unit <NUM> controls each unit (for example, the light-shielding plate <NUM>) of the illumination optical system <NUM> under the control of the main control unit <NUM>.

The mask <NUM> has a pattern to be transferred onto a substrate <NUM>, that is, the circuit pattern of a semiconductor device, and is illuminated by the illumination optical system <NUM>. The projection optical system <NUM> is formed from, for example, a refractive system or catadioptric system. The projection optical system <NUM> projects (forms) a pattern (its image) of the mask <NUM> onto the substrate <NUM> (one shot region of the substrate <NUM>) coated with a photoresist (photosensitizing agent) at a predetermined magnification (for example, <NUM>/<NUM>). The projection optical system <NUM> includes an aperture stop <NUM>. The aperture stop <NUM> is arranged in the pupil plane of the projection optical system <NUM>, that is, a Fourier transform plane corresponding to the mask <NUM>, and includes an almost circular opening portion.

The first drive unit <NUM> includes a motor and sets a predetermined NA (numerical aperture) by controlling the diameter of the opening portion of the aperture stop <NUM>. The second drive unit <NUM> drives (moves) an optical element constituting part of the lens system of the projection optical system <NUM> along the optical axis of the projection optical system <NUM>. This makes it possible to suppress degradation in aberrations of the projection optical system <NUM> and reduce a distortion error while properly maintaining the projection magnification. A projection system control unit <NUM> controls the respective units of the projection optical system <NUM> (the aperture stop <NUM> and the optical elements) via the first drive unit <NUM> and the second drive unit <NUM> under the control of the main control unit <NUM>.

As described above, the substrate <NUM> is a substrate onto which the pattern of the mask <NUM> is transferred (projected) and a photoresist is applied. The substrate <NUM> includes a wafer, a glass plate, and other types of substrates.

The substrate stage <NUM> is a stage that holds the substrate <NUM>. The third drive unit <NUM> moves the substrate stage <NUM> in three-dimensional directions, that is, a direction (Z direction) along the optical axis of the projection optical system <NUM> and a plane (X-Y plane) orthogonal to the direction. The third drive unit <NUM> includes a motor for moving the substrate stage <NUM>. In this embodiment, the direction along the optical axis of the projection optical system <NUM> is the Z direction (Z-axis), and the directions orthogonal to the optical axis of the projection optical system <NUM> are the X direction (X-axis) and the Y direction (Y-axis).

The laser interferometer <NUM> detects the distance to a mirror <NUM> fixed to the substrate stage <NUM> to measure the position of the substrate stage <NUM> in the X-Y plane. The alignment measurement system <NUM> measures a positional shift between the substrate <NUM> and the substrate stage <NUM>. The stage control unit <NUM> moves the substrate stage <NUM> to a predetermined position in the X-Y plane via the third drive unit <NUM> based on the measurement result obtained by the laser interferometer <NUM> and the measurement result obtained by the alignment measurement system <NUM> under the control of the main control unit <NUM>.

The focus measurement system <NUM> includes a projection optical system <NUM> and a detection optical system <NUM>, and measures the position of the substrate <NUM> in the direction along the optical axis of the projection optical system <NUM>, that is, the height of the surface of the substrate <NUM>. The projection optical system <NUM> projects light (non-exposure light) that does not sensitize the photoresist applied on the substrate <NUM> and focuses the light at each position on the substrate <NUM>. The light reflected at each position on the substrate <NUM> enters the detection optical system <NUM>.

The detection optical system <NUM> has a plurality of light-receiving elements for position detection arranged in correspondence with light reflected at each position on the substrate <NUM>. More specifically, the plurality of light-receiving elements for position detection are arranged such that the light-receiving surface of each light-receiving element is almost conjugate to each position (each reflection point) on the substrate <NUM> via an imaging optical system. Accordingly, the positional shift of the substrate <NUM> in the direction along the optical axis of the projection optical system <NUM> is measured as the positional shift of light entering each light-receiving element arranged on the detection optical system <NUM>.

The conveying unit <NUM> is a conveying mechanism for holding and conveying the substrate <NUM> between the conveying unit <NUM> and the substrate stage <NUM>. As shown in <FIG>, the conveying unit <NUM> includes a conveying port <NUM>, a first substrate hand <NUM>, a pre-alignment unit <NUM>, and a second substrate hand <NUM>. The details of the conveying unit <NUM> will be described later together with the conveyance of the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM>. <FIG> is a schematic plan view showing the arrangements of the substrate stage <NUM> and the conveying unit <NUM>.

A storage unit <NUM> stores various types of programs, data, and the like required to operate the exposure apparatus <NUM>. In this embodiment, the storage unit <NUM> also functions as an accumulation unit that stores and accumulates control information concerning the substrate stage <NUM> and the conveying unit <NUM> which is generated as a result of processing the substrate <NUM> in the exposure apparatus <NUM>. In this case, the control information includes holding forces with which the substrate stage <NUM> and the conveying unit <NUM> hold the substrate <NUM> and the times required for the substrate stage <NUM> and the conveying unit <NUM> to hold the substrate <NUM> with preset holding forces. In addition, the control information includes measurement values concerning the alignment of the substrate <NUM> when it is conveyed between the substrate stage <NUM> and the conveying unit <NUM> and the number of alignment errors. Note, however, the control information need not always include all the above information and may include at least one piece of the above information.

The main control unit <NUM> is formed from an information processing apparatus (computer), and comprehensively controls the respective units of the exposure apparatus <NUM> via the illumination system control unit <NUM>, the projection system control unit <NUM>, and the stage control unit <NUM> in accordance with programs stored in the storage unit <NUM>. The main control unit <NUM> controls exposure processing of forming a pattern on the substrate <NUM> by exposing the substrate <NUM> via the mask <NUM>. In addition, in this embodiment, the main control unit <NUM> functions as a determination unit that determines a conveying procedure when conveying the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM> based on control information accumulated in the storage unit <NUM>.

The conveyance of the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM> will be described with reference to <FIG>. The substrate stage <NUM> is provided with a chuck <NUM> that holds the substrate <NUM> on a holding surface. The substrate stage <NUM> is also provided with lifting pins <NUM> that are moved up and down by a drive unit (not shown) with respect to the holding surface on which the chuck <NUM> holds the substrate <NUM>. Note that the chuck <NUM> may be moved up and down by a drive unit (not shown), instead of the lifting pins <NUM>, to move the lifting pins <NUM> up and down relative to the holding surface of the chuck <NUM>.

Loading processing concerning the loading of the substrate <NUM> will be described first. In a device manufacturing factory, the substrate <NUM> is loaded into the exposure apparatus <NUM> via the conveying port <NUM> connecting the exposure apparatus <NUM> to an external apparatus. The first substrate hand <NUM> conveys the substrate <NUM> loaded into the exposure apparatus <NUM> to the pre-alignment unit <NUM> that performs pre-alignment (coarse positioning) of the substrate <NUM>. The second substrate hand <NUM> conveys the substrate <NUM> having undergone pre-alignment by the pre-alignment unit <NUM> to the substrate stage <NUM>. At this time, the substrate stage <NUM> has moved to a substrate loading position (first position) in advance. When the second substrate hand <NUM> transfers the substrate <NUM> to the substrate stage <NUM>, the lifting pins <NUM> receive first the substrate <NUM> while the lifting pins <NUM> have risen above the holding surface of the chuck <NUM>. The lifting pins <NUM> then move downward to make the chuck <NUM> hold (transfer) the substrate <NUM> received by the lifting pins <NUM>. The first substrate hand <NUM>, the pre-alignment unit <NUM>, the second substrate hand <NUM>, the lifting pins <NUM>, and the chuck <NUM> each hold the substrate <NUM> by, for example, vacuum suction. The chuck <NUM> completes loading processing by holding the substrate <NUM>.

Unloading processing concerning the unloading of the substrate <NUM> will be described next. When exposure processing for the substrate <NUM> is completed, the substrate stage <NUM> holding the substrate <NUM> moves to a substrate unloading position (first position). When the substrate stage <NUM> transfers the substrate <NUM> to the first substrate hand <NUM>, the lifting pins <NUM> move upward first on the substrate stage <NUM> to transfer the substrate <NUM> from the chuck <NUM> to the lifting pins <NUM>. The substrate <NUM> held by the lifting pins <NUM> is then transferred to the first substrate hand <NUM>. The first substrate hand <NUM> conveys the substrate <NUM> to the conveying port <NUM>. The unloading processing is completed by unloading the substrate <NUM> from the conveying port <NUM>.

The operation of the exposure apparatus <NUM> will be described with reference to <FIG>. In step S101, the exposure apparatus <NUM> determines whether a recipe (process) for a target lot (a plurality of substrates included in a lot) loaded into the exposure apparatus <NUM> is the one processed in the past. If the recipe for the target lot is the one processed in the past, the process shifts to step S102. If the recipe for the target lot is not the one processed in the past, the process shifts to step S103.

In step S102, when the same recipe as that for the target lot is processed as a conveying procedure at the time of the conveyance of a substrate <NUM> between a substrate stage <NUM> and a conveying unit <NUM>, the exposure apparatus <NUM> selects the conveying procedure (past conveying procedure) stored in a storage unit <NUM> in association with the recipe.

In step S103, the exposure apparatus <NUM> selects a conveying procedure (default conveying procedure) set by default as a conveying procedure when conveying the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM>.

In this embodiment, as conveying procedures at the time of the conveyance of the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM>, a plurality of conveying procedures that can be set for the substrate stage <NUM> and the conveying unit <NUM> are stored in the storage unit <NUM>. For example, the storage unit <NUM> stores first and second conveying procedures as the plurality of conveying procedures. Assume that in this case, the first conveying procedure (to be referred to as the "productivity-oriented procedure" hereinafter) prioritizes productivity concerning the conveyance of the substrates <NUM> more than the second conveying procedure. The second conveying procedure (to be referred to as the "stability-oriented procedure" hereinafter) prioritizes stability concerning the conveyance of the substrates <NUM> more than the first conveying procedure. The default conveying procedure may be the productivity-oriented procedure. Note that in the embodiment, the plurality of conveying procedures are two types of conveying procedures. However, this is not exhaustive. In addition, a default conveying procedure may be settable with parameters.

In step S104, the exposure apparatus <NUM> performs loading processing of loading the substrate <NUM> into the exposure apparatus <NUM>. The loading processing is the same as that described with reference to <FIG>, and hence a detailed description of the processing will be omitted.

In step S105, the exposure apparatus <NUM> stores, in the storage unit <NUM>, control information concerning the substrate stage <NUM> and the conveying unit <NUM>, which is generated as a result of loading the substrate <NUM>. More specifically, the storage unit <NUM> stores chucking pressures (holding forces) with which lifting pins <NUM> and a chuck <NUM> hold the substrate <NUM> and the chucking times required for the lifting pins <NUM> and the chuck <NUM> to hold the substrate <NUM> with preset chucking pressures.

In step S106, the exposure apparatus <NUM> performs alignment measurement processing. The alignment measurement processing is processing concerning the alignment of the substrate <NUM> which is performed when the substrate <NUM> is conveyed between the substrate stage <NUM> and the conveying unit <NUM>. The alignment measurement processing is processing for measuring a positional shift of the substrate <NUM>. More specifically, the alignment measurement processing includes the processing of measuring a positional shift between the substrate <NUM> and the substrate stage <NUM> and the processing of measuring a positional shift between a mask <NUM> and the substrate <NUM>.

In step S107, the exposure apparatus <NUM> stores, in the storage unit <NUM>, control information concerning the substrate stage <NUM> and the conveying unit <NUM> which is generated by aligning the substrate <NUM>. More specifically, the storage unit <NUM> stores measurement values concerning the alignment of the substrate <NUM> which is performed when the substrate <NUM> is conveyed between the substrate stage <NUM> and the conveying unit <NUM> and the number of errors in the alignment.

In step S108, the exposure apparatus <NUM> performs exposure processing of forming a pattern on the substrate <NUM> by exposing the substrate <NUM> via the mask <NUM> while controlling the relative position between the mask <NUM> and the substrate <NUM> in accordance with the alignment measurement processing performed in step S106.

In step S109, the exposure apparatus <NUM> performs unloading processing of unloading the substrate <NUM> from the exposure apparatus <NUM>. The unloading processing is the same as that described with reference to <FIG>, and hence a detailed description of the processing will be omitted.

In step S110, the exposure apparatus <NUM> stores, in the storage unit <NUM>, control information concerning the substrate stage <NUM> and the conveying unit <NUM> which is generated as a result of unloading the substrate <NUM>. More specifically, the storage unit <NUM> stores chucking pressures (holding forces) with which the lifting pins <NUM> and the chuck <NUM> hold the substrate <NUM> and the chucking times required for the lifting pins <NUM> and the chuck <NUM> to hold the substrate <NUM> with preset chucking pressures.

In step S111, the exposure apparatus <NUM> stores information indicating whether preset specific errors have occurred. In this case, the specific errors include, for example, a chucking error, that is, a failure in chucking the substrate <NUM> by the lifting pins <NUM> or the chuck <NUM>.

In step S112, the exposure apparatus <NUM> performs determination processing of determining a conveying procedure when conveying the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM>. The details of the determination processing will be described later with reference to <FIG>.

In step S113, the exposure apparatus <NUM> determines whether exposure processing has been performed for all the substrates <NUM> included in a lot. If exposure processing has not been performed for all the substrates <NUM> included in the lot, the process shifts to step S104 to perform exposure processing for the next substrate <NUM>. If exposure processing has been performed for all the substrates <NUM> included in the lot, the process shifts to step S114.

In step S114, the exposure apparatus <NUM> stores, in the storage unit <NUM>, an optimal conveying procedure (that is, the conveying procedure selected in step S102 or S103 or the conveying procedure determined in step S112) for a recipe for the target lot input in step S101 in association with the recipe.

The details of determination processing (step S112) of determining a conveying procedure when conveying the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM> will be described with reference to <FIG> and <FIG>. In the following description, the threshold set for each control information accumulated (stored) in the storage unit <NUM> is set as the first threshold, and the threshold set for the number of substrates <NUM> in the lot which exceed the first threshold is set as the second threshold.

In step S201, the exposure apparatus <NUM> reads out a conveying procedure stored in the storage unit <NUM>. In step S202, the exposure apparatus <NUM> determines whether the chucking pressure and the chucking time concerning the chuck <NUM> in the loading processing which are stored in the storage unit <NUM> in step S105 are equal to or less than the first thresholds set for them. If the chucking force and the chucking time concerning the chuck <NUM> are not equal to or less than the first thresholds, the process shifts to step S203. If the chucking force and the chucking time concerning the chuck <NUM> are equal to or less than the first thresholds, the process shifts to step S205.

In step S203, the exposure apparatus <NUM> counts the number of substrates <NUM> in the lot which exceed the first thresholds in terms of the chucking pressure and the chucking time concerning the chuck <NUM> in the loading processing. In step S204, the exposure apparatus <NUM> determines whether the number of substrates <NUM> counted in step S203 is equal to or less than the second threshold set for it. If the number of substrates <NUM> counted in step S203 is not equal to or less than the second threshold, the process shifts to step S223. If the number of substrates <NUM> counted in step S203 is equal to or less than the second threshold, the process shifts to step S205.

In step S223, the exposure apparatus <NUM> determines whether the conveying procedure is changed (determined) in the lot. If the conveying procedure is not changed in the lot, the process shifts to step S224. If the conveying procedure is changed in the lot, the process shifts to step S225.

In step S224, the exposure apparatus <NUM> changes (determines) the conveying procedure and stores the conveying procedure in the storage unit <NUM>. In this embodiment, if, for example, the current conveying procedure is a productivity-oriented procedure, the conveying procedure is changed to a stability-oriented procedure for the following reason. If the conveying procedure is a productivity-oriented procedure, it is necessary to perform recovery processing for an error, resulting in a deterioration in productivity. Accordingly, changing the conveying procedure to a stability-oriented procedure prioritizing stability will improve the productivity. As disclosed in <CIT>, the exposure apparatus <NUM> may change drive parameters and the first thresholds concerning the respective units of the substrate stage <NUM> and the conveying unit <NUM> as well as changing the conveying procedure.

In step S225, the exposure apparatus <NUM> determines whether measurement values concerning alignment and the number of errors in alignment exceed the first thresholds set for them. If the measurement values concerning alignment and the number of errors in alignment exceed the first thresholds, the process shifts to step S226 to notify the corresponding information, for example, information indicating that the error factor may be a process (lot) factor. In other words, if the conveying procedure is changed and the measurement values concerning alignment and the number of errors in alignment do not change before and after the change in conveying procedure, the exposure apparatus <NUM> notifies the corresponding information. Such notification is performed via, for example, the display or audio output device of the exposure apparatus <NUM>, and hence the display or audio output device functions as a notification unit.

In step S205, the exposure apparatus <NUM> determines whether the chucking pressure and the chucking time concerning the lifting pins <NUM> in loading processing which are stored in the storage unit <NUM> in step S105 are equal to or less than the first thresholds set for them. If the chucking pressure and the chucking time concerning the lifting pins <NUM> are not equal to or less than the first thresholds, the process shifts to step S206. If the chucking pressure and the chucking time concerning the lifting pins <NUM> are equal to or less than the first thresholds, the process shifts to step S208.

In step S206, the exposure apparatus <NUM> counts the number of substrates <NUM> in the lot which exceed the first thresholds concerning the chucking pressure and the chucking time concerning the lifting pins <NUM> in the loading processing. In step S207, the exposure apparatus <NUM> determines whether the number of substrates <NUM> counted in step S206 is equal to or less than the second threshold set for it. If the number of substrates <NUM> counted in step S206 is not equal to or less than the second threshold, the process shifts to step S223. If the number of substrates <NUM> counted in step S206 is equal to or less than the second threshold, the process shifts to step S208.

In step S208, the exposure apparatus <NUM> determines whether the alignment measurement value in alignment measurement processing which is stored in the storage unit <NUM> in step S107 is equal to or less than the first threshold set for the alignment measurement value. If the alignment measurement value is not equal to or less than the first threshold, the process shifts to step S209. If the alignment measurement value is equal to or less than the first threshold, the process shifts to step S211.

In step S209, the exposure apparatus <NUM> counts the number of substrates <NUM> in the lot which exceed the first threshold concerning the alignment measurement value. In step S210, the exposure apparatus <NUM> determines whether the number of substrates <NUM> counted in step S209 is equal to or less than the second threshold set for the number of substrates. If the number of substrates <NUM> counted in step S209 is not equal to or less than the second threshold, the process shifts to step S223. If the number of substrates <NUM> counted in step S209 is equal to or less than the second threshold, the process shifts to step S211.

In step S211, the exposure apparatus <NUM> determines whether an alignment error has occurred, based on the number of alignment errors in the alignment measurement processing which is stored in the storage unit <NUM> in step S107. If an alignment error has occurred, the process shifts to step S212. If no alignment error has occurred, the process shifts to step S214.

In step S212, the exposure apparatus <NUM> counts the number of substrates <NUM> in the lot in which alignment errors have occurred concerning the number of alignment errors. In step S213, the exposure apparatus <NUM> determines whether the number of substrates <NUM> counted in step S212 is equal to or less than the second threshold set for the number of substrates. If the number of substrates <NUM> counted in step S212 is not equal to or less than the second threshold, the process shifts to step S223. If the number of substrates <NUM> counted in step S212 is equal to or less than the second threshold, the process shifts to step S214.

In step S214, the exposure apparatus <NUM> determines whether the chucking pressure and the chucking time concerning the chuck <NUM> in the unloading processing which are stored in the storage unit <NUM> in step S110 are equal to or less than the first thresholds set for them. If the chucking pressure and the chucking time concerning the chuck <NUM> are not equal to or less than the first thresholds, the process shifts to step S215. If the chucking pressure and the chucking time concerning the chuck <NUM> are equal to or less than the first thresholds, the process shifts to step S217.

In step S215, the exposure apparatus <NUM> counts the number of substrates <NUM> in the lot which exceed the first threshold concerning the chucking pressure and the chucking time concerning the chuck <NUM> in the unloading processing. In step S216, the exposure apparatus <NUM> determines whether the number of substrates <NUM> counted in step S215 is equal to or less than the second threshold. If the number of substrates <NUM> counted in step S215 is not equal to or less than the second threshold, the process shifts to step S223. If the number of substrates <NUM> counted in step S215 is equal to or less than the second threshold, the process shifts to step S217.

In step S217, the exposure apparatus <NUM> determines whether the chucking pressure and the chucking time concerning the lifting pins <NUM> in the unloading processing which are stored in the storage unit <NUM> in step S110 are equal to or less than the first thresholds set for them. If the chucking pressure and the chucking time concerning the lifting pins <NUM> are not equal to or less than the first thresholds, the process shifts to step S218. If the chucking pressure and the chucking time concerning the lifting pins <NUM> are equal to or less than the first thresholds, the process shifts to step S220.

In step S218, the exposure apparatus <NUM> counts the number of substrates <NUM> in the lot which exceed the first thresholds concerning the chucking pressure and the chucking time concerning the lifting pins <NUM> in the unloading processing. In step S219, the exposure apparatus <NUM> determines whether the number of substrates <NUM> counted in step S218 is equal to or less than the second threshold set for the number of substrates. If the number of substrates <NUM> counted in step S218 is not equal to or less than the second threshold, the process shifts to step S223. If the number of substrates <NUM> counted in step S218 is equal to or less than the second threshold, the process shifts to step S220.

In step S220, the exposure apparatus <NUM> determines whether a specific error has occurred, based on information indicating the presence/absence of the specific error which is stored in the storage unit <NUM> in step S111. If the specific error has occurred, the process shifts to step S221. If the specific error has not occurred, the determination processing is terminated.

In step S221, the exposure apparatus <NUM> counts the number of substrates <NUM> in the lot in which specific errors have occurred. In step S222, the exposure apparatus <NUM> determines whether the number of substrates <NUM> counted in step S221 is equal to or less than the second threshold set for the number of substrates. If the number of substrates <NUM> counted in step S221 is not equal to or less than the second threshold, the process shifts to step S223. Note that with regard to a specific error, the exposure apparatus <NUM> changes, for example, the first thresholds for the chucking pressures of the chuck <NUM> and the lifting pins <NUM> in step S224. If the number of substrates <NUM> counted in step S221 is equal to or less than the second threshold, the determination processing is terminated.

A productivity-oriented procedure as one of conveying procedures in this embodiment will be described with reference to <FIG>. In step S301, the substrate <NUM> is loaded into the exposure apparatus <NUM> via a conveying port <NUM>. In step S302, a first substrate hand <NUM> conveys (moves) the substrate <NUM> loaded into the exposure apparatus <NUM> to a pre-alignment unit <NUM>. In step S303, the pre-alignment unit <NUM> transfers the substrate <NUM> to the second substrate hand <NUM>. In step S304, the substrate <NUM> is transferred from a second substrate hand <NUM> to the lifting pins <NUM> at a substrate loading position.

In step S305, the exposure apparatus <NUM> moves the second substrate hand <NUM> in the Y-axis minus direction to make the second substrate hand <NUM> retract from the substrate loading position. In step S306, the exposure apparatus <NUM> moves the substrate stage <NUM> in the Y-axis plus direction to make the substrate stage <NUM> retract to a non-interference region where the substrate stage <NUM> does not interfere with the second substrate hand <NUM> that has been made to retract in step S305. In step S307, the exposure apparatus <NUM> moves the substrate stage <NUM> in the Z-axis plus direction to drive the substrate stage <NUM> to a front interference region where the substrate stage <NUM> interferes with the second substrate hand <NUM>.

In the productivity-oriented procedure, the exposure apparatus <NUM> concurrently performs steps S305, S306, and S307 in this manner. In other words, the productivity-oriented procedure is a procedure for concurrently performing a procedure for making the conveying unit <NUM> retract from the substrate loading position after the conveying unit <NUM> transfers the substrate <NUM> to the substrate stage <NUM> at the substrate loading position and a procedure for making the substrate stage <NUM> retract from the substrate loading position. This improves productivity concerning the loading of substrates <NUM>.

After the completion of the concurrent processing of steps S305, S306, and S307, the lifting pins <NUM> transfer the substrate <NUM> to the chuck <NUM> in step S308. Thus, the exposure apparatus <NUM> terminates the conveying procedure prioritizing productivity.

A stability-oriented procedure as one of the conveying procedures in this embodiment will be described with reference to <FIG>. In step S401, the substrate <NUM> is loaded into the exposure apparatus <NUM> via the conveying port <NUM>. In step S402, the first substrate hand <NUM> conveys (moves) the substrate <NUM> loaded into the exposure apparatus <NUM> to the pre-alignment unit <NUM>. In step S403, the pre-alignment unit <NUM> transfers the substrate <NUM> to the second substrate hand <NUM>. In step S404, the second substrate hand <NUM> transfers the substrate <NUM> to the lifting pins <NUM> at the substrate loading position.

In step S405, the exposure apparatus <NUM> moves the second substrate hand <NUM> in the Y-axis minus direction to make the second substrate hand <NUM> retract from the substrate loading position. In step S406, the exposure apparatus <NUM> moves the substrate stage <NUM> in the Z-axis plus direction to drive the substrate stage <NUM> to an interference region where the substrate stage <NUM> interferes with the second substrate hand <NUM>.

In this manner, in the stability-oriented procedure, the exposure apparatus <NUM> inhibits the movement of the substrate stage <NUM> while the lifting pins <NUM> hold the substrate <NUM>. In other words, the stability-oriented procedure is a procedure for sequentially performing a procedure for making the conveying unit <NUM> retract from the substrate loading position after the conveying unit <NUM> transfers the substrate <NUM> to the substrate stage <NUM> at the substrate loading position and a procedure for making the substrate stage <NUM> retract from the substrate loading position. This improves stability concerning the loading of substrates <NUM>.

After the completion of the processing in steps S405 and S406, the lifting pins <NUM> transfer the substrate <NUM> to the chuck <NUM> in step S407. Thus, the exposure apparatus <NUM> terminates the conveying procedure prioritizing stability.

This embodiment has exemplified the conveying procedure used when the substrate <NUM> is loaded. However, the present invention can also be applied to a conveying procedure when the substrate <NUM> is unloaded. A conveying procedure prioritizing productivity and a conveying procedure prioritizing stability at the time of unloading the substrate <NUM> will be described below.

A conveying procedure prioritizing productivity when unloading the substrate <NUM> will be described with reference to <FIG>. In step S501, the chuck <NUM> transfers the substrate <NUM> to the lifting pins <NUM>. In step S502, the exposure apparatus <NUM> moves the substrate stage <NUM> in the Z-axis minus direction to drive the substrate stage <NUM> to a non-interference region where the substrate stage <NUM> does not interfere with the first substrate hand <NUM>.

In step S503, the exposure apparatus <NUM> moves the substrate stage <NUM> to drive the substrate stage <NUM> to a substrate unloading position. In step S504, the exposure apparatus <NUM> moves the first substrate hand <NUM> in the Y-axis plus direction to drive the first substrate hand <NUM> to the substrate unloading position.

In this manner, in the conveying procedure prioritizing productivity, the exposure apparatus <NUM> concurrently performs steps S503 and S504. In other words, this conveying procedure is a procedure for concurrently performing a procedure for moving the substrate stage <NUM> to the substrate unloading position before the conveying unit <NUM> receives the substrate <NUM> from the substrate stage <NUM> at the substrate unloading position and a procedure for moving the conveying unit <NUM> to the substrate unloading position. This improves productivity concerning the unloading of the substrates <NUM>.

After the completion of the concurrent processing in steps S503 and S504, the lifting pins <NUM> transfer the substrate <NUM> to the first substrate hand <NUM> in step S505. In step S506, the substrate <NUM> is unloaded from the exposure apparatus <NUM> through the conveying port <NUM>. Thus, the exposure apparatus <NUM> terminates the conveying procedure prioritizing productivity when unloading the sub strate <NUM>.

A conveying procedure prioritizing stability when unloading the substrate <NUM> will be described with reference to <FIG>. In step S601, the exposure apparatus <NUM> moves the substrate stage <NUM> to drive the substrate stage <NUM> to the substrate unloading position. In step S602, the chuck <NUM> transfers the substrate <NUM> to the lifting pins <NUM>. In step S603, the exposure apparatus <NUM> moves the substrate stage <NUM> in the Z-axis minus direction to drive the substrate stage <NUM> to a non-interference region where the substrate stage <NUM> does not interfere with the first substrate hand <NUM>. In step S604, the exposure apparatus <NUM> moves the first substrate hand <NUM> in the Y-axis plus direction to drive the first substrate hand <NUM> to a substrate conveying position.

In this manner, in the conveying procedure prioritizing stability, the exposure apparatus <NUM> inhibits the movement of the substrate stage <NUM> while the lifting pins <NUM> hold the substrate <NUM>. In other words, this conveying procedure is a procedure for sequentially performing a procedure for moving the substrate stage <NUM> to the substrate unloading position before the conveying unit <NUM> receives the substrate <NUM> from the substrate stage <NUM> at the substrate unloading position and a procedure for moving the conveying unit <NUM> to the substrate unloading position. This improves stability concerning the unloading of the substrates <NUM>.

In step S605, the lifting pins <NUM> transfer the substrate <NUM> to the first substrate hand <NUM>. In step S606, the substrate <NUM> is unloaded from the exposure apparatus <NUM> through the conveying port <NUM>. Thus, the exposure apparatus <NUM> terminates the conveying procedure prioritizing stability when unloading the substrate <NUM>.

In this manner, in this embodiment, the exposure apparatus <NUM> determines (changes) a conveying procedure when conveying the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM> based on control information concerning the substrate stage <NUM> and the conveying unit <NUM> which is generated as a result of conveying the substrate <NUM>. In this case, the exposure apparatus <NUM> determines a conveying procedure when conveying the substrate <NUM> by selecting one of the plurality of conveying procedures stored in the storage unit <NUM> based on each control information and the result of comparison between each control information and a threshold set for each control information. In the embodiment, while continuously processing the plurality of substrates <NUM> included in the same lot, the exposure apparatus <NUM> determines a conveying procedure when conveying the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM>. However, the exposure apparatus <NUM> may also determine a conveying procedure when conveying the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM> for each lot or each preset number of substrates. According to the embodiment, it is possible to automatically determine (change) an optimal conveying procedure for conveying the substrate <NUM> between the substrate stage <NUM> and the conveying unit <NUM> in accordance with a process. This makes it possible to improve productivity while maintaining stability.

An example of a specific effect of the determination processing shown in <FIG> will be described. When, for example, the current chucking pressure is lower than the chucking pressure stored (accumulated) in the storage unit <NUM> or the current chucking time is shorter than the chucking time stored (accumulated) in the storage unit <NUM>, it is estimated that the amount of warpage of the substrate <NUM> is large or the flatness of the reverse surface of the substrate <NUM> is low. Assume that the exposure apparatus <NUM> conveys the substrate <NUM> according to the productivity-oriented procedure. In this case, when the exposure apparatus <NUM> moves the substrate stage <NUM> while the lifting pins <NUM> hold the substrate <NUM> (step S306), the positional shift of the substrate <NUM> can occur. In addition, the substrate <NUM> may drop from the lifting pins <NUM>. In such a case, the exposure apparatus <NUM> selects the stability-oriented procedure because the stability-oriented procedure can improve productivity concerning the conveyance of the substrates <NUM> more than the productivity-oriented procedure.

A measurement value concerning alignment and the number of errors in alignment are used when the chucking pressure and the chucking time are similar to the chucking pressure and the chucking time stored (accumulated) in the storage unit <NUM>. If the measurement value concerning alignment is an abnormal value or an alignment error has occurred, it is estimated that the contact surface between the substrate <NUM> and the lifting pins <NUM> has been contaminated or physically defected. In such a case, the exposure apparatus <NUM> selects the stability-oriented procedure because the stability-oriented procedure can improve productivity concerning the conveyance of the substrates <NUM> more than the productivity-oriented procedure.

The exposure apparatus <NUM> may further include a user interface <NUM> that provides the user with a setting screen for setting first and second thresholds. <FIG> shows an example of a setting screen <NUM> for setting first and second thresholds which is provided (displayed) on a display or touch panel as the user interface <NUM>. A main control unit <NUM> provides the user interface <NUM>.

On the setting screen <NUM>, a parameter <NUM> serves to set the first threshold for the chucking pressure of the chuck <NUM> in loading processing. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which the chucking pressure of the chuck <NUM> in loading processing exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the first threshold for the chucking time of the chuck <NUM> in loading processing. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which the chucking time of the chuck <NUM> in loading processing exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the first threshold for the chucking pressure of the lifting pins <NUM> in loading processing. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which the chucking pressure of the lifting pins <NUM> in loading processing exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the first threshold for the chucking time of the lifting pins <NUM> in loading processing. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which the chucking time of the lifting pins <NUM> in loading processing exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the first threshold for measurement values concerning alignment. Note that a plurality of first thresholds may be set for measurement values concerning alignment. For example, the first thresholds may be respectively set for the X-axis, the Y-axis, and the rotational axis. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which a measurement value concerning alignment exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the second threshold for the number of alignment errors. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the first threshold for the chucking pressure of the chuck <NUM> in unloading processing. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which the chucking pressure of the chuck <NUM> in unloading processing exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the first threshold for the chucking time of the chuck <NUM> in unloading processing. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which the chucking time of the chuck <NUM> in unloading processing exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the first threshold for the chucking pressure of the lifting pins <NUM> in unloading processing. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which the chucking pressure of the lifting pins <NUM> in unloading processing exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set the first threshold for the chucking time of the lifting pins <NUM> in unloading processing. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> for each of which the chucking time of the lifting pins <NUM> in unloading processing exceeds the first threshold. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set an error number corresponding to a specific error. A parameter <NUM> serves to set the second threshold concerning the number of substrates <NUM> having undergone a specific error. A parameter <NUM> serves to set a conveying procedure to be determined (changed) when the second threshold is exceeded in the same lot.

A parameter <NUM> serves to set a default conveying procedure.

The first embodiment has exemplified the case in which a conveying procedure is determined (changed) by using each threshold set for each piece of control information. However, this is not exhaustive. For example, a conveying procedure may be determined (changed) by using a learning model obtained by machine learning.

In the second embodiment, first of all, learning data indicating the relationship between input data and teacher data is prepared. In this case, the input data is data including at least one of a measurement value concerning a chucking pressure, chucking time, or alignment and the number of alignment errors. The teacher data is data indicating a proper conveying procedure for input data. The data indicating a proper conveying procedure can be data indicating two values respectively representing being proper and improper. Note that as data indicating a proper conveying procedure, data indicating a value (for example, a natural number from <NUM> to <NUM>) representing a stepwise evaluation of properness or data indicating the probability (for example, a real number from <NUM> to <NUM>) of being proper.

It is possible to obtain input data such as measurement values concerning chucking pressures, chucking times, and alignment and the number of alignment errors by usual substrate processing. A conveying procedure as output data can be derived by calculating statistics from each input data (control information) accumulated in a storage unit <NUM> and productivity. It is also possible to derive a conveying procedure from an experiment of obtaining each input data by processing various types of substrates <NUM> and comparing productivities.

A learning model for determining a proper conveying procedure is obtained by using learning data. Learning data can be obtained by using, for example, a neural network. The neural network is a model having a multilayer network structure including an input layer, an intermediate layer, and an output layer. It is possible to obtain a learning data by optimizing random variables inside the network by an algorithm such as a backpropagation method using learning data indicating the relationship between input data and teacher data. This embodiment has exemplified the case in which a learning model is obtained by using a neural network. However, this is not exhaustive. For example, other models and algorithms such as a support vector machine and a determination tree may be used.

Inputting new input data to the obtained learning model will output data indicating a proper conveying procedure as output data. A proper conveying procedure can be determined based on the output data.

Note that the first embodiment and the second embodiment can be selectively executed. In other words, setting can be made to determine a conveying procedure by using each threshold set for each piece of control information or determine a conveying procedure by using the learning model obtained by machine learning. For example, as shown in <FIG>, two checkboxes <NUM> and <NUM> are provided on the setting screen <NUM> provided on the user interface <NUM>. The checkbox <NUM> is a checkbox for selecting to determine a conveying procedure by using each threshold. The checkbox <NUM> is a checkbox for selecting to determine a conveying procedure by using a learning model.

Claim 1:
A substrate processing apparatus (<NUM>) for processing a substrate, the apparatus comprising:
a stage (<NUM>) configured to hold and move a substrate to be processed;
a conveying unit (<NUM>) configured to hold and convey the substrate to be processed between the conveying unit and the stage;
characterized by further comprising
an accumulation unit (<NUM>) configured to accumulate control information concerning the stage and the conveying unit generated as a result of previous processing of a substrate that has already been processed; and
a determination unit (<NUM>) configured to determine (S112) a conveying procedure for conveying the substrate to be processed between the stage and the conveying unit by selecting one of a plurality of conveying procedures which can be set for the stage and the conveying unit based on the control information accumulated in the accumulation unit.