JP7187890B2 - SUBSTRATE TRANSFER MODULE AND SUBSTRATE TRANSFER METHOD - Google Patents

Description

The present disclosure relates to a substrate transfer module and a substrate transfer method.

2. Description of the Related Art In a semiconductor device manufacturing process, a semiconductor wafer (hereinafter referred to as a wafer), which is a substrate, is transported within a factory while being stored in a transport container. A semiconductor device manufacturing apparatus is constructed such that a wafer is taken out from the transfer container and subjected to vacuum processing. Patent Document 1 describes a mini-environment device, which is a module for taking out the wafer. This mini-environment apparatus includes a frame, a transfer robot that transfers the wafer within the frame, oxygen concentration meters provided above and below the wafer transfer path for monitoring the oxygen concentration within the frame, It has

JP 2014-38888 A

The present disclosure provides a technique that can prevent the influence of gas emitted from a substrate in a substrate transfer module.

The substrate transfer module of the present disclosure includes a housing,
a first substrate transfer port provided on a side wall of the housing;
a second substrate transfer port provided in a side wall of the housing, which is freely openable and closable, for transferring a substrate between a module provided outside the housing and inside the housing;
The container main body of a transfer container configured by a container main body and a lid body and in which the substrates are stored is arranged so that the rim portion of the substrate unloading port opening into the container main body is the rim portion of the first substrate transfer port. a plurality of load ports that are connected to the side wall of the housing so as to be in close contact with each other, and perform opening and closing of the substrate unloading port and opening and closing of the first substrate transfer port by attaching and detaching the lid to and from the container body;
a transport mechanism provided in the housing for transporting the substrate between the first substrate transport port and the second substrate transport port;
a clean gas supply unit that supplies clean gas into the housing;
an exhaust mechanism for exhausting the inside of the housing;
a suction hole that opens above a transport path of the substrate transported between the first substrate transport port and the second substrate transport port in the housing and sucks the atmosphere in the housing;
a detection unit that detects a component contained in the gas released from the substrate moving on the transport path in the sucked atmosphere;
with
the suction hole opens above the first substrate transfer port in the side wall of the housing;
A plurality of the first substrate transfer ports are provided in the horizontal direction,
a plurality of the suction holes are provided, each positioned above the plurality of first substrate transfer ports;
The plurality of suction holes are provided at equal intervals in the horizontal direction and positioned at the same height,
for supplying, to each of the detection units, the gas released from the substrate having a temperature higher than the temperature inside the housing, which is transported toward each of the plurality of first substrate transport ports by the transport mechanism; A pump provided for each suction hole is provided.

According to the present disclosure, it is possible to prevent the influence of the gas released from the substrate in the substrate transfer module.

1 is a plan view of a substrate processing apparatus that is an embodiment of the present disclosure; FIG. 3 is a schematic vertical cross-sectional side view of a film forming module provided in the substrate processing apparatus; FIG. It is a vertical side view of the loader module provided in the said substrate processing apparatus. It is a longitudinal side view of the said loader module. Figure 3 is a cross-sectional plan view of the loader module; FIG. 4 is a graph diagram for explaining detection of chlorine performed in the loader module; It is a graph chart explaining transition of chlorine concentration. It is a block diagram of the control part provided in the said substrate processing apparatus. It is explanatory drawing of the flow implemented in the said control part. FIG. 11 is a longitudinal side view showing another configuration example of the loader module; FIG. 11 is a cross-sectional plan view showing still another configuration example of the loader module; It is a graph chart which shows the result of an evaluation test. It is a graph chart which shows the result of an evaluation test. It is a graph chart which shows the result of an evaluation test. It is a graph chart which shows the result of an evaluation test.

A vacuum processing apparatus 1 including a loader module 4, which is an embodiment of the present disclosure, will be described with reference to FIG. The loader module 4 is, for example, a horizontally long EFEM (Equipment Front End Module). The loader module 4, which will be described in detail later, is configured as a substrate transfer module for taking out a plurality of wafers W from a transfer container B, which is a closed container for storing the wafers W, and loading them into the vacuum processing apparatus 1. FIG.

An alignment module 11 for adjusting the orientation and eccentricity of the wafer W is provided on the side of the loader module 4 . This alignment module 11 is also configured as a substrate transfer module. Load lock modules 12 and 13 are provided on the left and right sides of the rear side of the loader module 4 . The load lock modules 12 and 13 are configured in the same manner as each other, and are provided with a stage 14 for placing the wafer W thereon and making it stand by. The load lock modules 12 and 13 have their interiors changed between a normal pressure atmosphere of N ₂ (nitrogen) gas atmosphere and a vacuum atmosphere in order to transfer the wafer W between the loader module 4 and a vacuum transfer module 15 which will be described later. configured to be switchable. Gate valves G1 are interposed between the load lock modules 12 and 13 and the loader module 4, respectively.

On the rear side of the load lock modules 12 and 13, there is provided a vacuum transfer module 15 whose interior is in a vacuum atmosphere. The vacuum transfer module 15 has a transfer arm 16 . Four film forming modules 2 are connected to the vacuum transfer module 15 along its circumference, and a gate valve G2 is interposed between the vacuum transfer module 15 and the film forming modules 2 . This film forming module 2 forms a TiN (titanium nitride) film on the surface of the wafer W in a vacuum atmosphere.

The wafers W stored in the transport container B are transported in the order of the loader module 4→alignment module 11→loader module 4→load lock module 12 (13)→vacuum transfer module 15→film formation module 2 and subjected to film formation. be. The wafer W subjected to the film forming process is transferred in the order of film forming module 2→vacuum transfer module 15→load lock module 12 (13)→loader module 4→transfer container B1. Transfer of the wafer W between the load lock modules 12 and 13, the vacuum transfer module 15, and the film forming module 2 is performed by the transfer arm 16 described above. Transfer of the wafer W between the alignment module 11 , the loader module 4 , and the load lock modules 12 and 13 is performed by a transfer mechanism 40 provided in the loader module 4 , which will be described later.

Next, the configuration of the film forming module 2 will be described with reference to the schematic diagram of FIG. The film forming module 2 has a vacuum vessel 21 . Reference numeral 22 in the figure denotes a transfer port of the vacuum container 21 which is opened and closed by the gate valve G2. An exhaust port 23 is opened in the vacuum container 21 for evacuating the inside of the vacuum container 21 to form a vacuum atmosphere with a predetermined pressure. The exhaust port 23 is connected to an exhaust mechanism 24 such as a vacuum pump. A stage 25 on which a wafer W is placed is provided in the vacuum container 21 , and the stage 25 is provided with a heater 26 for heating the wafer W. As shown in FIG.

A gas supply unit 27 facing the stage 25 is provided above the stage 25, and the gas supply unit 27 is configured as, for example, a shower head. Each downstream end of a first pipe 28 and a second pipe 29 is connected to the gas supply unit 27 . The upstream side of the first pipe 28 is branched and connected to, for example, a TiCl ₄ (titanium tetrachloride) gas supply source 31 as a raw material gas and to, for example, an N ₂ gas supply source 32 as a replacement gas. The upstream side of the second pipe 29 is branched and connected to, for example, an NH ₃ (ammonia) gas supply source 33 as a reducing gas and an N ₂ gas supply source 34 as a replacement gas, for example. Each of these gas supply sources 31 to 34 includes valves and the like, and supplies each gas to the gas supply section. During the film forming process, TiCl ₄ gas and NH ₃ gas are alternately and repeatedly supplied from the gas supply unit 27 while the wafer W is heated to a predetermined temperature by the heater 26 . Also, during the period between the period in which the TiCl ₄ gas is supplied and the period in which the NH ₃ gas is supplied, the N ₂ gas is supplied as a purge gas from the gas supply unit 27 . That is, in this film formation module 2, ALD (Atomic Layer Deposition) is performed on the wafer W to form a TiN film.

Next, the loader module 4 will be described in detail with reference to the longitudinal side view of FIG. 3 as well. The loader module 4 has a square housing 41, and the housing 41 is configured in a horizontally long rectangular shape in plan view. The housing 41 is made of metal such as aluminum. A transfer port 42, which is a second substrate transfer port that is opened and closed by the gate valve G1, is opened on the right and left sides of the rear side wall of the housing 41 at intervals. The transport ports 42 are formed at the same height. In the housing 41, a table 43 is provided which can be moved left and right and which can be raised and lowered. The transfer arm 44 and the table 43 are also made of metal such as aluminum. By the movement of the table 43 and the cooperation of the transfer arm 44, the transfer of the wafer W is performed between the transfer container B of each load port 6 described later and the stages 14 of the load lock modules 12 and 13 described above. The platform 43 and the transport arm 44 are configured as a transport mechanism 40 .

A fan filter unit (FFU) 45 is provided in the ceiling of the housing 41 . One end of a gas supply pipe 46 is connected to the FFU 45 , and the other end of the gas supply pipe 46 is connected to an air supply source 47 . The FFU 45, gas supply pipe 46 and atmospheric supply source 47 constitute a clean gas supply. The FFU 45 includes an air supply fan 48 that constitutes the upper part of the FFU 45 and downwardly supplies the atmosphere supplied from the gas supply pipe 46, and is provided below the air supply fan 48. and a filter 49 that cleans the air supplied from the fan 48 by filtering it and supplies it downward. The speed of the airflow in the housing 41 and the amount of air supplied to the housing 41 are adjusted by the rotational speed of the air supply fan 48 . An exhaust port 51 is opened at the bottom of the housing 41, and the exhaust port 51 is connected to an exhaust fan 52 forming an exhaust mechanism. The exhaust amount from the exhaust port 51 is adjusted by the number of revolutions of the exhaust fan 52 .

A side wall on the front side of the housing 41 , that is, a side wall facing the side wall provided with the above-described transfer port 42 is provided with a transfer port 61 . The three transfer ports 61 are provided at the same height and are formed with equal intervals left and right (see FIG. 1). A load port 6 for loading/unloading the wafer W from the transfer container B into the housing 41 and for opening/closing the transfer port 61 is provided for each transfer port 61 . The transport container B is, for example, a FOUP (Front Open Unified Pod), and is composed of a container body B1 and a lid B2 that can be attached to and detached from the container body B1. The lid B2 opens and closes the substrate outlet B3 formed in front of the container body B1 by being attached to and detached from the container body B1. The lid B2 has a locking mechanism (not shown) and is fixed to the container body B1 by the locking mechanism.

The load port 6 is composed of a support base 62 , a moving stage 63 , an opening/closing door 64 and a moving mechanism 65 . The support base 62 protrudes forward from a position below the transfer port 61 outside the housing 41 . The moving stage 63 moves back and forth on the support table 62 with the transport container B placed thereon. By this movement of the moving stage 63, as shown in FIG. 3, the edge portion B4 of the substrate outlet B3 of the container main body B1 is brought into a state of being in close contact with the edge portion 66 of the transfer port 61 from the outside of the housing 41. The wafer W can be transferred to and from the main body B1. The position of the container body B1 when the rim portion B4 is in close contact with the rim portion 66 is defined as the delivery position.

The opening/closing door 64 can be positioned in the closed position shown in FIG. The opening/closing door 64 is provided with an unlocking mechanism (not shown), and when the container body B1 is positioned at the transfer position and the opening/closing door 64 is positioned at the closed position as described above, the locking mechanism of the lid B2 is activated. Then, the state in which the lock is formed between the container body B1 and the lid B2 and the state in which the lock is released can be switched. The lid B2 thus unlocked from the container body B1 is supported by the opening/closing door 64 . The moving mechanism 65 can move the opening/closing door 64 that supports the lid B2 between the closed position and the open position behind and below the closed position. The open position is a position where the opening/closing door 64 is retracted from the transfer path of the wafer W when the wafer W is transferred between the transfer container B and the load lock modules 12 and 13 . FIG. 4 shows a state in which the opening/closing door 64 is moved to the open position and the wafer W is returned from the load lock module 13 to the transfer container B by the transfer mechanism 40 .

The moving stage 63 has a gas supply section 68 connected to the inside of the container body B1 when the container body B1 is placed thereon. One end of a gas supply path 69 is connected to the gas supply section 68. there is The other end of the gas supply path 69 is connected to an N ₂ gas supply source 72 via a flow rate regulator 71 . The _N2 gas supply source 72 supplies _N2 gas as a purge gas into the container body B1 when the container body B1 is positioned at the delivery position and the lid body B2 is positioned at the open position. As a result, the gas inside the container body B1 is purged, and the purged gas is exhausted and removed from the exhaust port 51 in the housing 41 as indicated by the dotted line in FIG. The flow rate adjusting section 71 includes a mass flow controller and is configured to adjust the amount of purge gas supplied from the gas supply section 68 . The gas supply section 68, the gas supply path 69, the flow rate adjustment section 71 and the _N2 gas supply source 72 constitute a purge gas supply section.

By supplying the purge gas from the gas supply unit 68, it is possible to reduce the concentration of the gas discharged from the wafer W, which will be described later, in the container body B1, and to create an environment in which the wafer W is subjected to the next processing. It is possible to suppress the introduction of the components that constitute the gas. For example, the purge gas is supplied from the gas supply unit 68 after the open/close door 64 moves from the closed position to open the cover B2 and the transfer port 61, and then the open/close door 64 moves to the closed position to open the cover B2 and the transfer port 61. It continues until the transfer port 61 is closed.

A suction hole 73 is opened above each transfer port 61 in the side wall inside the housing 41 . Since the suction hole 73 is opened at such a position, the suction hole 73 opens above the transfer path of the wafer W moving from the transfer port 42 corresponding to the load lock module 13 to the transfer port 61 corresponding to each load port 6 . There will be Further, each gas suction hole 73 is provided at the same height and spaced apart from each other corresponding to the position of each transfer port 61 . As will be described later, by performing suction from the suction holes 73, the concentration of chlorine discharged from the wafer W passing through each transfer port 61 is detected. The chlorine concentration of the passing wafer W is detected under the same conditions.

5, one end of a pipe 74 is connected to each gas suction hole 73, and the other end of each pipe 74 is connected to an analysis section 76. As shown in FIG. Therefore, in this example, three sets of transfer port 61, load port 6, suction hole 73, pipe 74, and analysis unit 76 are provided. The analysis unit 76 includes, for example, a pump 79 , and gas sucked from the suction hole 73 by the pump 79 is introduced into the analysis unit 76 . Then, the analysis unit 76 transmits, for example, an analog voltage signal corresponding to the concentration of chlorine (Cl) in the atmosphere thus introduced as a detection signal to the control unit 8 described later.

There is no particular limitation on the method of detecting chlorine (Cl) performed by the analysis unit 76, and known detection methods such as ion mobility spectroscopy and ion chromatography can be used. The suction by the analysis unit 76 is always performed while the loader module 4 is in operation, for example. As for the pipe 74, for example, a soft pipe made of resin may be used, or a hard pipe made of stainless steel, for example, may be used. The pipe 74 may be routed so that the analysis unit 76 is provided at a position away from the housing 41 , or the pipe 74 may be routed so that the analysis unit 76 is provided in the housing 41 . Also, the analysis unit 76 sucks gas at, for example, 2 L/min, but this is an example, and the amount of suction is not limited to such. As will be described later, based on the gaseous chlorine sucked from the suction hole 73 provided above one of the three transfer ports 61, the analysis unit 76 connected to the suction hole 73 generates a detection signal. The operation of the load port 6 that outputs and opens and closes the transfer port 61 is controlled. Therefore, the transport port 61, the load port 6, the suction hole 73, and the analysis section 76 may be described as the transport port 61, the load port 6, the suction hole 73, and the analysis section 76 corresponding to each other.

The reason why the chlorine concentration is detected as described above will be explained. As described above, TiCl ₄ is used for film formation in the film formation module 2 , so chlorine (Cl) remains on the wafer W carried out from the film formation module 2 , and the chlorine (Cl) is removed from the wafer W. Cl) containing gas will be released. The gas emitted from this wafer W is called outgas. Chlorine (Cl) in the outgas causes a chemical reaction with moisture contained in the air when the wafer W is transported to the loader module 4 in the atmosphere to produce hydrochloric acid, and the loader module 4 is composed of the hydrochloric acid. The metal forming the housing 41, the transport mechanism 40, and the like corrodes. That is, the outgas containing chlorine (Cl) is a corrosive gas that corrodes the metal forming the loader module 4 .

The temperature of the wafers W collected in the transfer container B is higher than the temperature inside the housing 41 of the loader module 4 due to the heating during the film formation process. For example, the temperature inside the housing 41 is about 25.degree. Since the temperature of the wafer W is higher than the ambient temperature, the outgassing of the wafer W forms an ascending current due to thermophoresis. Since the rising air current is formed in this manner, the area above the transfer port 61 through which the wafer W having undergone the film formation process passes in the housing 41 is likely to be exposed to the outgassing, and is relatively prone to corrosion. is. Therefore, in this example, the chlorine concentration in the area where this corrosion tends to progress is measured with high accuracy, and the suction hole 73 is opened to the area so that the occurrence and progress of the corrosion can be suppressed by the measures described later. there is However, as will be described later, it is not limited to providing the suction holes 73 at such positions.

Next, the controller 8 will be explained. The control unit 8 transmits a control signal to each unit of the vacuum processing apparatus 1 so that the wafer W can be transferred and processed as described above. Further, the concentration of chlorine in the sucked gas is detected based on the detection signal output from each analysis section 76 described above. Therefore, the control unit 8 and the analysis unit 76 are configured as a chlorine detection unit. Furthermore, when the chlorine concentration rises, the control unit 8 outputs a control signal to each unit so that a coping operation, which will be described later, is performed.

The suction from the suction hole 73 and the detection of the chlorine concentration by the analysis unit 76 are always performed during the operation of the vacuum processing apparatus 1, for example. Since the outgas discharged from the wafer W forms an upward air current as described above, when the wafer W passes under the suction hole 73 and is returned to the transfer container B, the gas sucked from the suction hole 73 is contains a large amount of chlorine (Cl), and the detected chlorine concentration rises sharply. After that, when the wafer W is stored in the transfer container B, the chlorine concentration in the gas sucked from the suction hole 73 gradually decreases. In the graph of FIG. 6, the chlorine concentration (unit: ppb) is set on the vertical axis, and the elapsed time (unit: seconds) is set on the horizontal axis. In FIG. 6, for three wafers W sequentially transferred to the same transfer container B, if the analysis unit 76 detects the concentration of chlorine released from only one of the three wafers W, the waveform is as follows. Different line types are used for each wafer W. FIG. Regarding the waveforms, the first wafer W is indicated by a solid line, the second wafer W is indicated by a one-dot chain line, and the third wafer W is indicated by a two-dot chain line. Since each wafer W is processed in the same manner, it is considered that the gas is released in the same manner. Therefore, each waveform has the same shape.

However, the wafers W are transferred to the transfer container B periodically at relatively short intervals. In other words, when one wafer W is transferred to the transfer container B and the gas from the wafer W is supplied toward the suction hole 73 , the transfer container B precedes the wafer W in the vicinity of the suction hole 73 . The gas discharged from the wafer W conveyed to 1 remains, and this residual gas is also supplied to the suction hole 73 . Therefore, when the wafers W are periodically transferred to the transfer container B, the chlorine accumulates near the suction holes 73 and the detected chlorine concentration increases as the order of the wafers W transferred increases. Specifically, the chlorine concentration detected at time t0 when the third wafer W is returned to the transfer container B in the graph of FIG. The chlorine concentrations A1 and A2 of the remaining outgassed from the first and second wafers W correspond to the accumulated concentrations, that is, A1+A2+A3.

Therefore, when a large number of wafers W are periodically transferred to the transfer container B, the detected chlorine concentration values are considered to form a waveform as shown in the graph of FIG. 7, for example. The vertical axis and horizontal axis of the graph in FIG. 7 indicate the chlorine concentration and time, respectively, similarly to the graph in FIG. The timings at which the wafers W pass below the suction holes 73 are respectively shown. Every time the wafer W passes under the suction hole 73, the chlorine concentration rises sharply and then drops sharply. The peak value increases as the passes through . As described above, the chlorine concentration value detected during the transfer of the wafer W fluctuates up and down. Only the chlorine concentration is extracted and treated as the chlorine concentration, and the presence or absence of abnormality is determined by comparing it with the preset allowable value. Acquisition of the chlorine concentration waveform and detection of the chlorine concentration from the waveform are performed immediately after receiving the detection signal. That is, the chlorine concentration is detected in real time while the wafer W is being transported.

Next, the configuration of the control unit 8 will be described with reference to FIG. The control unit 8 includes a bus 81, a CPU 82, a program storage unit 83, a memory 84, and an alarm output unit 85. The bus 81 is connected to the CPU 82, the program storage unit 83, the memory 84, and the alarm output unit 85. . The analysis unit 76 is connected to the bus 81, and is configured so that the control unit 8 can receive the aforementioned detection signal. In the drawing, the detection signal is indicated by a dotted arrow.

A program 86 is stored in the program storage unit 83 described above. In the program 86, a control signal is transmitted from the control unit 8 to each unit of the vacuum processing apparatus 1 so that the above-described flow of transfer and processing of the wafer W, detection of the chlorine concentration, and coping operation to be described later is executed. Instructions (each step) are incorporated. This program 86 is stored in a storage medium such as a compact disk, hard disk, MO (magneto-optical disk), or DVD and installed in the program storage unit 83 .

By the way, the control unit 8 is constructed so that when the detected chlorine concentration rises, it can execute a coping operation to deal with this rise. As the coping operation of this embodiment, an increase in the number of rotations of the air supply fan 48 of the FFU 45, an increase in the amount of exhaust from the exhaust port 51 due to an increase in the number of rotations of the exhaust fan 52, is an increase in the amount of purge gas supplied to the container body B1. In FIG. 8, the control signals for executing coping operations that are sent to the air supply fan 48, the exhaust fan 52, and the flow rate adjustment unit 71 are indicated by dashed arrows.

The memory 84 stores the permissible value of the chlorine concentration, the reference rotation speed of the air supply fan 48, and the reference rotation speed of the exhaust fan 52. FIG. For example, when the chlorine concentration is determined to be normal, the air supply fan 48 and the exhaust fan 52 rotate at the reference rotation speeds stored in the memory 84. The air-supply fan 48 and the exhaust fan 52 rotate at the rotational speed increased by a fixed amount. A predetermined amount of increase with respect to the reference number of revolutions is also stored in the memory 84, for example. Further, the memory 84 stores the correspondence relationship between the detected value of the chlorine concentration and the amount of purge gas supplied to the container body B1 by the flow rate adjusting section 71 . This correspondence relationship is set so that the larger the detected value of the chlorine concentration, the larger the supply amount of the purge gas. The purge gas supply amount is determined based on this correspondence relationship and the detected value of the chlorine concentration, and the operation of the flow rate adjusting unit 71 is controlled so as to achieve the determined supply amount. That is, the above correspondence relationship is data for feedback-controlling the purge gas supply amount according to the detected value of the chlorine concentration.

The alarm output unit 85 is composed of, for example, a monitor and a speaker, and outputs an alarm as an image or sound to notify the user of the device that an abnormality has occurred. Note that different types of alarms may be output according to the detected value of the chlorine concentration.

Next, based on the flow of FIG. 9, the operation of the loader module 4 when the wafer W is transferred between the modules and processed as described above will be described. In the loader module 4 , the air-supply fan 48 of the FFU 45 rotates at the reference rotation speed, and the exhaust fan 52 rotates at the reference rotation speed, forming a downward air current inside the housing 41 . On the other hand, suction from each suction hole 73 is performed, and a detection signal is transmitted from each analysis unit 76 to the control unit 8 . In this state, the transporting container B is sequentially transported to each load port 6 by a transporting mechanism (not shown).

Then, the wafers W stored in the transfer container B are unloaded, and as described above, the unloaded wafers W undergo the film forming process in the film forming module 2 and are returned to the transport container B. FIG. The transfer container B in which all the unloaded wafers W have been returned is withdrawn from the load port 6 by the transfer mechanism for the transfer container. A new transport container B is transported to the empty load port 6 . As described above, while the transfer port 61 is opened by the load port 6, the gas provided to the load port 6 is supplied at a supply amount corresponding to the chlorine concentration detected by the analysis unit 76 corresponding to the load port 6. A purge gas is supplied from the supply unit 68 into the container body B1 of the transfer container B to perform purging.

As described with reference to FIG. 7, every time the wafer W is returned to the transfer container B, a peak appears in the chlorine concentration waveform obtained from each detection signal, and the value of this peak is detected as the chlorine concentration (step S1). ). It is determined whether or not the detected chlorine concentration exceeds an allowable value (step S2). If it is determined that the permissible value is not exceeded, the chlorine concentration is regarded as normal. Then, when it is determined that there is no abnormality, the detection of the chlorine concentration is continued in step S1, and the rotation of the air supply fan 48 at the reference rotation speed and the rotation of the exhaust fan 52 at the reference rotation speed are stopped. each performed.

Assume that the chlorine concentration detected by any of the analysis units 76 exceeds the allowable value in step S2, for example, and is determined to be abnormal. In that case, the current upper limit value and the purge gas supply amount of the load port 6 corresponding to the analysis unit 76 that detected the abnormal chlorine concentration are set to the current upper limit and It is determined whether or not it is (step S3). If it is determined in step S3 that the number of revolutions of the air supply fan 52 and the number of revolutions of the exhaust fan 53 are not the upper limit values, the number of revolutions is increased by a predetermined amount. Further, when it is determined that the purge gas supply amount is not the upper limit value, it is increased to a value corresponding to the detected chlorine concentration. Among the number of rotations of the air supply fan 52, the number of rotations of the exhaust fan 53, and the purge gas supply amount, the operation is continued with the upper limit value determined to be the upper limit value. Further, an alarm indicating that the chlorine concentration has become abnormal is output from the alarm output unit 85 (step S4).

When the number of revolutions of the air supply fan 48 and the exhaust fan 52 increases in step S4, the amount of exhaust air in the housing 41 increases and the velocity of the downward air current increases. Thereby, chlorine (Cl) is efficiently removed from the inside of the housing 41, and even if the wafer W is newly transferred from the load lock module 12 (13) to the transfer container B, the detected peak value of the chlorine concentration is compared. be of low value. Further, when the amount of purge gas supplied from the gas supply unit 68 is increased in step S4, the interior of the container body B1 is efficiently purged, and chlorine (Cl) remaining on the surfaces of the wafers W stored in the container body B1 is removed. is reliably and quickly removed, and the chlorine (Cl) concentration in the container body B1 is lowered.

After step S4 is performed, it is determined whether or not the detected chlorine concentration has fallen below the allowable value (step S5). If it is determined in this step S5 that the value has not decreased below the allowable value, the above-described step S3 is executed again. If it is determined in step S5 that the rotation speed has fallen below the allowable value, the rotation speed of the air supply fan 48 and the rotation speed of the exhaust fan 52 are each lowered to the reference rotation speed. In addition, the supply amount of the purge gas decreases as the chlorine concentration decreases. On the other hand, the alarm output from the alarm output unit 85 is stopped (step S6). After step S6, it is determined whether or not the wafer W has been transferred by the loader module 4 (step S7). If it is determined in step S7 that the transportation has ended, detection of the chlorine concentration in the loader module 4 is stopped, and if it is determined that the transportation has not ended, each step after step S1 is executed. be done. Further, in step S3, when the number of rotations of the air supply fan 52, the number of rotations of the exhaust fan 53, and the purge gas supply amount have reached the upper limit values, these parameters are operated with the upper limit values. Similar to step S7, it is determined whether or not the wafer W has been transferred by the loader module 4 (step S8). If it is determined in step S8 that the transportation has ended, the detection of the chlorine concentration is stopped, and if it is determined that the transportation has not ended, whether the chlorine concentration detected in step S5 is equal to or less than the allowable value. A determination is made as to whether or not

In the loader module 4 constituting the vacuum processing apparatus 1 described above, a suction hole is formed in the side wall of the housing 41 so as to open above the transfer path of the wafer W returned to the transfer container B from the load lock module 12 (13). 73 is opened to more detect the chlorine concentration in the sucked gas. When the detected chlorine concentration increases, the number of rotations of the FFU 45 and the exhaust fan 52 is increased to suppress the increase in the chlorine concentration in the housing 41 . Therefore, it is possible to suppress the corrosion of the metal of each part inside the housing 41 . Therefore, it is possible to prevent foreign matter generated by corrosion from adhering to the wafer W, so that the yield of the wafer W can be prevented from being lowered. In addition, since the supply amount of the purge gas to the container body B1 is increased as a coping operation, chlorine is suppressed from being brought into the transfer destination of the wafers W by the transfer container B. FIG. As a result, deterioration of the environment of the transfer destination of the wafer W can be prevented. Since the supply amount of the purge gas corresponds to the detected chlorine concentration, it is possible to prevent excessive supply of the purge gas and reduce the amount of purge gas used. Therefore, it is possible to save energy in operating the device.

By the way, the coping operation performed when the chlorine concentration increases is not limited to the above example. For example, when the chlorine concentration is determined to be abnormal as described above, the operation of the transfer mechanism 40 may be stopped to stop the transfer of the wafer W in the loader module 4 . As a result, it is possible to prevent the wafer W, to which foreign substances due to corrosion may have adhered, from being brought into an environment where the wafer W is subjected to the next process. The operation of the transfer mechanism 40 may be immediately stopped when it is determined to be abnormal, or the operation may be stopped after all the wafers W unloaded from the transfer container B are returned to the transfer container B. That is, the timing for stopping the operation of the transport mechanism 40 may be set arbitrarily. Regarding the operation performed according to the chlorine concentration, any one of the number of revolutions of the air supply fan 48, the number of revolutions of the exhaust fan, the amount of purge gas supplied to the load port 6, and the operation of the transport mechanism 40 is selected. Only one or only selected ones of these may be performed.

Further, for example, the flow rate of air supplied from the FFU 45 may be changed, for example, according to the chlorine concentration. Specifically, for example, a gas supply pipe 46 connected to the FFU 45 may be provided with a flow rate adjusting unit having a mass flow controller so that the higher the chlorine concentration, the greater the amount of air supplied to the FFU 45 . By the way, in the above example, the amount of exhaust air from the exhaust port 51 is controlled by controlling the rotational speed of the exhaust fan 52 according to the chlorine concentration. do not have. For example, an exhaust pipe having a valve interposed therebetween may be provided between the exhaust fan 52 and the exhaust port 51, and when the chlorine concentration is high, the degree of opening of this valve may be increased to increase the exhaust amount. In the above example, the rotation speeds of the air supply fan 48 and the exhaust fan 52 are changed in two stages: the reference rotation speed and the reference rotation speed + the predetermined increase amount. It is not limited to being changed in stages. For example, a correspondence relationship between the detected chlorine concentration and the rotation speed may be set, and the rotation speed may be changed in multiple stages based on the correspondence relationship.

By the way, when a relatively high chlorine concentration is detected, an operation is performed to reduce the chlorine concentration in the housing 41 by controlling the rotational speeds of the air supply fan 48 and the exhaust fan as described above. Although examples have been described where such operations may not occur. For example, the controller 8 is provided with a monitor that displays the detected chlorine concentration. Advantageously, the user of the apparatus can consider when to replace or clean, for example, the metal parts in the housing 41 based on the display of the chlorine concentration on the monitor.

In the above example, the control unit 8 constantly receives detection signals from the analysis unit 76 and detects the chlorine concentration. Detection may be performed only at certain times. For example, the detection is started when the first wafer W of the lot is unloaded from the load lock module 12 (13), and the period until the last wafer W of the lot is completely transported to the transport container B (wafer recovery period). ) to detect the chlorine concentration. Chlorine concentration detection by the control unit 8 may not be performed during a period other than the wafer collection period. Furthermore, in the above example, as shown in FIG. 7, the peak value of the waveform is used as the chlorine concentration for comparison with the permissible value. Not limited. For example, an average value may be calculated in a predetermined interval during the wafer recovery period, and this average value may be treated as the chlorine concentration.

By the way, the suction hole 73 may be provided in the loader module 4 so as to open to the transfer path of the wafer W. As shown in FIG. Therefore, for example, a pipe projecting from the inner wall of the housing 41 is provided, and a hole at the tip of this pipe is used as a suction hole 73. The atmosphere above the transport path may be captured and detected. The suction hole 73 of this pipe is not limited to opening sideways. For example, the suction hole 73 may open downward by bending the pipe.

Further, as shown in FIG. 10 , a suction hole 73 may be provided above the transfer port 61 and a suction hole 73 may be provided above the transfer port 42 connected to the load lock module 13 . For convenience of explanation, the suction hole 73 opening above the transfer port 61 is referred to as 73A, and the suction hole 73 opening above the transfer port 42 is referred to as 73B. 73A is a first suction hole, and 73B is a second suction hole. By opening at the above position, the suction hole 73B is also opened above the transfer path of the wafer W returning from the load lock module 13 to the container body B1, like the suction hole 73A. The suction hole 73B is also connected to the analysis section 76 via a pipe 74 in the same manner as the suction hole 73A. The controller 8 is configured to be able to detect the concentration of chlorine in the gases sucked from the suction holes 73A and 73B.

When the suction holes 73A and 73B are provided in this way, for example, the chlorine concentration in the gas sucked from the suction hole 73A exceeds the allowable value and the chlorine concentration in the gas sucked from the suction hole 73B exceeds the allowable value. If so, the control unit 8 as a determination unit determines that there is an abnormality. Then, as described in step S3 of FIG. 9, each coping operation for coping with the increase in chlorine concentration may be executed. On the other hand, when both or one of the chlorine concentration in the gas sucked from the suction hole 73A and the chlorine concentration in the gas sucked from the suction hole 73B is below the allowable value, it is determined to be normal. It may be so determined that the above coping operation is not performed. That is, it is possible to determine whether there is an abnormality based on the components in the gas sucked from the suction holes 73A and the components in the gas sucked from the suction holes 73B.

Further, for example, one of the load lock modules may be used for unprocessed wafers and the other for processed wafers, and the suction port 73B above each transport port 42 may correspond to each other as shown in FIG.

In this case, for example, the control unit 8 determines the chlorine concentration in the gas sucked from the suction hole 73B above the transfer port 42 of the load lock module 12 and the suction hole 73B above the transfer port 42 of the load lock module 13. It may be configured to calculate a difference value from the chlorine concentration in the gas to be measured. Then, the control unit 8 determines whether or not this difference value is, for example, an allowable value or less. may Specifically, the chlorine concentration of the gas emitted from the wafer W before the film formation process and sucked by the suction hole 73B above the transfer port 42 of the load lock module 12 is defined as the pre-treatment chlorine concentration. Further, the chlorine concentration of the gas emitted from the wafer W after the film formation process and sucked by the suction hole 73B above the transfer port 42 of the load lock module 13 is taken as post-process chlorine concentration. The controller 8 may determine whether or not there is an abnormality in the vacuum processing apparatus 1 based on the pre-treatment chlorine concentration and the post-treatment chlorine concentration.

In addition, by sucking gas from these suction holes 73A and 73B and detecting the chlorine concentration, the user of the device can grasp the degree of chlorine concentration at each position in the housing 41. . Therefore, the user can prepare replacement parts for each position according to the grasped chlorine concentration, which is advantageous. Note that the chlorine concentration may be detected by providing only one of the suction holes 73A and 73B. By the way, an example in which the suction holes 73 are provided above the transfer ports 42 and 61 of the wafer W has been shown. It may be provided above the transfer path of the wafer W between the port 42 and the transfer port 61 . Therefore, the suction holes 73 are not limited to being provided above the transport ports 42 and 61, and may be opened in the alignment module 11, for example.

In the film forming module 2, for example, TiCl ₄ gas and H ₂ gas may be supplied to the wafer W to form a Ti film by CVD (Chemical Vapor Deposition). In this case as well, outgassing containing chlorine (Cl) is likely to be emitted from the wafers W transferred to the transfer container B, so it is effective to detect the chlorine concentration with the loader module 4 described above. The processing module for supplying a processing gas to the wafer W to process the wafer W, which constitutes the vacuum processing apparatus 1, is not limited to the film formation module. There may be a pre-clean module that removes Also, when the wafer W is processed using a chlorine-based gas other than TiCl ₄ , the outgas of the wafer W also contains chlorine (Cl), so it is effective to detect the chlorine concentration as described above. becomes. Although the illustrated vacuum processing apparatus 1 is a cluster-type vacuum processing apparatus having four film forming modules 2, the number of film forming modules 2 is not limited to four, and may be four or more, for example. , eight deposition modules 2 . Moreover, any form may be used as long as the wafer W can be processed without being exposed to the atmosphere.

Further, in the atmospheric atmosphere of the loader module 4, the element that corrodes metals is not limited to chlorine (Cl), and includes, for example, Br (bromine). Therefore, for example, the wafer W processed by supplying the gas containing Br may be returned to the transfer container B, and the analysis unit 76 may detect Br. Gas processing containing Br includes, for example, polysilicon etching processing using HBr gas. Further, the analysis unit 76 only needs to be able to detect the components contained in the outgassing emitted from the wafer W and output a detection signal corresponding to the amount of the components. It is not limited to detection of gas components.

Further, as shown in an evaluation test described later, the lower the processing temperature of the wafer W in the film forming module 2, the less the amount of sublimation of chlorine from the wafer W during the film forming process. Easy to bring into module 4. In the evaluation test described later, the detected chlorine concentration was relatively high when the treatment temperature was 500° C. or lower. Therefore, when the wafer W is processed at 500° C. or lower in the film forming module 2 or the etching module connected to the vacuum transfer module 15, detecting the chlorine concentration as described above is particularly effective.

In addition, the embodiment disclosed this time should be considered as an example and not restrictive in all respects. The above-described embodiments may be omitted, substituted or modified in various ways without departing from the scope and spirit of the appended claims.

(Evaluation test)
Evaluation tests conducted in connection with embodiments of the present disclosure will now be described. This evaluation test was conducted using a test apparatus substantially similar to the vacuum processing apparatus 1 described above, but this test apparatus does not have the suction holes 73 described above. In this test apparatus, the upper portion of the container body B1 at the transfer position and the gas concentration analyzer corresponding to the analysis section 76 were connected via a pipe. This gas concentration analyzer sucks the inside of the container body B1 from above through a pipe, and measures the concentration of chlorine in the outgas of the wafer W that has undergone the film forming process and is returned to the container body B1. is configured to

Evaluation test 1
In the evaluation test 1-1, the chlorine concentration measured when a plurality of wafers W on which the TiN films were formed in the film forming module 2 were returned to the container body B1 was examined. The temperature during the TiN film formation process is set to different temperatures within the range of 440° C. to 680° C. for each wafer W. FIG. In this evaluation test 1-1, the wafer W on which the uneven pattern is formed (a wafer W with a surface area 10 times larger than the surface area of the wafer W without the uneven pattern (bare wafer) W). ) was used. In addition, as evaluation test 1-2, evaluation test 1 was performed except that a wafer W on which an uneven pattern was formed so as to have a surface area five times as large as that of bare wafer W (referred to as wafer W having a surface area five times larger than that of bare wafer W) was used. -1 was tested in the same way.

The graph of FIG. 12 shows the time course of the chlorine concentration detected from the wafer W processed at 440° C. in the evaluation tests 1-1 and 1-2, and the vertical axis of the graph is the chlorine concentration ( ppb), and the horizontal axis of the graph indicates the measurement time (unit: seconds). Note that A on the vertical axis of the graph of FIG. 12 and each graph showing the results of the evaluation test, which will be described later, is a positive integer. In the graph of FIG. 12, the results of evaluation test 1-1 are indicated by solid lines, and the results of evaluation test 1-2 are indicated by dotted lines. In both evaluation tests 1-1 and 1-2, the waveforms of the graphs sharply rise and then fall sharply, and peaks appear in the waveforms. Also for each wafer W processed at a temperature other than 440° C., a peak appeared in the waveform similarly to the wafer W processed at 440° C. FIG.

The graph of FIG. 13 shows the chlorine concentrations at the peak values of the waveforms described in FIG. 12 detected from wafers W subjected to film formation processing at each processing temperature. The vertical axis of the graph represents the chlorine concentration (unit: ppb), which is the peak value, and the horizontal axis represents the treatment temperature (unit: °C). The plots in the graph representing the results of the evaluation test 1-1 are connected by solid lines, and the plots in the graph representing the results of the evaluation test 1-2 are connected by dotted lines.

As shown in the graph of FIG. 13, in both Evaluation Tests 1-1 and 1-2, the lower the temperature during the film formation process, the higher the peak chlorine concentration. This is probably because, as described above, if the temperature during the film formation process is low, the amount of chlorine removed by the heat during the film formation process is small. Therefore, it can be seen that detecting the chlorine concentration as described in the embodiment is particularly effective when the temperature during the film formation process is relatively low as described above. In addition, in this evaluation test, the outgassing of the wafer W is sucked from the container body B1, but since the outgassing is emitted upward as described above, even if it is sucked from the side wall of the housing 41 as in the embodiment, the same is true. It is thought that the concentration of chlorine can be measured in In other words, from the result of this evaluation test 1, it is estimated that the concentration of chlorine emitted from the wafer W can be expressed as a numerical value when the loader module 4 is configured as shown in the embodiment. As is clear from the graph of FIG. 13, when the temperature during the film forming process is the same in Evaluation Tests 1-1 and 1-2, the peak chlorine concentration in Evaluation Test 1-1 is higher. Therefore, it has been confirmed that monitoring the chlorine concentration is particularly effective when processing a wafer W having a large surface area.

Evaluation test 2
As evaluation test 2-1, 25 wafers W of the same lot subjected to TiN film formation processing at 440° C. are periodically returned to the container body B1 using the test apparatus used in evaluation test 1. Chlorine concentrations were monitored at times. This evaluation test 2-1 was set so that 25 wafers W could be film-formed per hour and returned to the container body B1. As evaluation test 2-2, substantially the same test as evaluation test 2-1 was conducted. set to

The graph in FIG. 14 shows the results of evaluation test 2-1, and the graph in FIG. 15 shows the results of evaluation test 2-2. In each graph, the horizontal axis indicates measurement time (unit: seconds), and the vertical axis indicates chlorine concentration (unit: ppb). In both evaluation tests 2-1 and 2-2, peaks appeared in the waveforms of the graphs corresponding to the timing at which each wafer W returned to the container body B1. In the evaluation test 2-1, among the peaks corresponding to the first to twentieth wafers W, the peaks corresponding to the later wafers W have higher chlorine concentration values. The peak chlorine concentration values corresponding to the twentieth and subsequent wafers W were substantially constant. In the evaluation test 2-2, with respect to the peaks corresponding to the first to twenty-fifth wafers W, the peaks corresponding to the later wafers W have higher chlorine concentration values, and correspond to the twenty-fifth wafer W. The peak chlorine concentration was greater than the maximum peak chlorine concentration in Evaluation Test 2-1.

In this example, the chlorine concentration is measured by sucking the inside of the container body B1, but the chlorine concentration has a similar waveform even when the suction hole is provided in the side wall of the housing 41 as described in the embodiment and the measurement is performed. It is considered to be. Therefore, as described with reference to FIG. 7, it is possible to determine whether there is an abnormality based on the peak value of the waveform. Moreover, from this evaluation test 2, it was confirmed that the chlorine concentration detected differs depending on the transfer speed of the wafer W. FIG.

W wafer 4 loader module 42 transfer port 40 transfer mechanism 45 FFU
52 Exhaust fan 6 Load port 61 Transfer port 73 Suction hole 76 Analysis unit 8 Control unit

Claims (10)

a housing;
a first substrate transfer port provided on a side wall of the housing;
a second substrate transfer port provided in a side wall of the housing, which is freely openable and closable, for transferring a substrate between a module provided outside the housing and inside the housing;
The container main body of a transfer container configured by a container main body and a lid body and in which the substrates are stored is arranged so that the rim portion of the substrate unloading port opening into the container main body is the rim portion of the first substrate transfer port. a plurality of load ports that are connected to the side wall of the housing so as to be in close contact with each other, and perform opening and closing of the substrate unloading port and opening and closing of the first substrate transfer port by attaching and detaching the lid to and from the container body;
a transport mechanism provided in the housing for transporting the substrate between the first substrate transport port and the second substrate transport port;
a clean gas supply unit that supplies clean gas into the housing;
an exhaust mechanism for exhausting the inside of the housing;
a suction hole that opens above a transport path of the substrate transported between the first substrate transport port and the second substrate transport port in the housing and sucks the atmosphere in the housing;
a detection unit that detects a component contained in the gas released from the substrate moving on the transport path in the sucked atmosphere;
with
the suction hole opens above the first substrate transfer port in the side wall of the housing;
A plurality of the first substrate transfer ports are provided in the horizontal direction,
a plurality of the suction holes are provided, each positioned above the plurality of first substrate transfer ports;
The plurality of suction holes are provided at equal intervals in the horizontal direction and positioned at the same height,
for supplying, to each of the detection units, the gas released from the substrate having a temperature higher than the temperature inside the housing, which is transported toward each of the plurality of first substrate transport ports by the transport mechanism; A substrate transfer module including a pump provided for each of the suction holes . The housing is made of metal,
2. The substrate transfer module according to claim 1, wherein the component detected by said detection unit is a component that corrodes said metal in the atmosphere within said housing. 3. The substrate transfer module according to claim 2, wherein said component is chlorine. 4. The substrate transfer module according to claim 1, wherein the substrate transfer path is a transfer path for substrates transferred from the second substrate transfer port to the first substrate transfer port. The detection unit detects the concentration of the component,
5. The substrate transfer module according to claim 1 , further comprising a judgment unit for judging whether or not there is an abnormality based on the concentration of the detected component and a preset permissible value of the concentration. The suction holes include a first suction hole and a second suction hole respectively opening above the first substrate transfer port and above the second substrate transfer port in a side wall of the housing,
The detection unit detects a concentration of a component in the atmosphere sucked through the first suction hole and a concentration of a component in the atmosphere sucked through the second suction hole,
6. The substrate transfer module according to claim 5 , wherein the determination unit determines whether or not there is an abnormality based on the concentration of each detected component and a preset allowable value. According to the detection result by the detection unit,
7. The apparatus according to any one of claims 1 to 6 , further comprising a controller for outputting a control signal so as to control the operation of at least one of the clean gas supply unit, the exhaust mechanism and the transport mechanism. Substrate transfer module. The load port is provided with a purge gas supply mechanism for purging the interior of the container body from which the lid has been removed,
The control unit
Instead of outputting a control signal to control the operation of at least one of the clean gas supply unit, the exhaust mechanism and the transport mechanism according to the detection result of the detection unit,
8. The substrate transfer module according to claim 7 , which outputs a control signal to control at least the operation of the purge gas supply mechanism according to the detection result of the detection section. The flow rate of the purge gas supplied to the container main body connected to the first substrate transfer port during transfer of the substrate to the first substrate transfer port by the transfer mechanism is determined according to the detection result. 9. The substrate transfer module of claim 8, wherein the substrate transfer module is controlled. a step of transporting the substrate between a first substrate transport port and a second substrate transport port respectively provided in a side wall of the housing by a transport mechanism provided in the housing;
opening and closing the second board transfer port for transferring the board between a module provided outside the housing and the inside of the housing;
By each of the plurality of load ports, the transport container in which the substrates are stored is moved such that the rim of the substrate unloading port provided in the transport container is in close contact with the rim of the first substrate transport port. a step of connecting to a side wall of a housing and opening and closing the lid and opening and closing the first substrate transfer port;
supplying clean gas into the enclosure by a clean gas supply;
exhausting the inside of the housing with an exhaust mechanism;
a step of sucking the atmosphere in the housing by means of a suction hole opening above a transport path for the substrates transported between the first substrate transport port and the second substrate transport port in the housing; ,
a step of detecting, by a detection unit, a component contained in the gas released from the substrate moving on the transport path in the sucked atmosphere;
with
the suction hole opens above the first substrate transfer port in the side wall of the housing;
A plurality of the first substrate transfer ports are provided in the horizontal direction,
a plurality of the suction holes are provided, each positioned above the plurality of first substrate transfer ports;
The plurality of suction holes are provided at equal intervals in the horizontal direction and positioned at the same height,
The step of sucking the atmosphere in the housing includes gas released from the substrate having a temperature higher than the temperature in the housing, which is transported toward each of the plurality of first substrate transport ports by the transport mechanism. to the detection unit by a pump provided for each of the suction holes .

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