Semiconductor manufacturing device and processing method

A semiconductor manufacturing device includes a stage, a plurality of pins, and a driving unit. The stage includes a mounting surface. The mounting surface has a first region for mounting thereon a substrate, and a second region for mounting thereon a focus ring. The second region is provided to surround the first region. A plurality of holes is formed in the stage. The holes extend in a direction that intersects the mounting surface while passing through the boundary between the first region and the second region. The pins are provided in the respective holes. Each of the pins has a first and a second upper end surface. The second upper end surface is provided above the first upper end surface, and is offset towards the first region with respect to the first upper end surface. The driving unit moves the pins up and down in the aforementioned direction.

FIELD OF THE INVENTION

Various aspects of the present invention relate to a semiconductor manufacturing device and a processing method.

BACKGROUND OF THE INVENTION

Patent Document 1 discloses a semiconductor manufacturing device. The semiconductor manufacturing device described in Patent Document 1 includes a stage and a plurality of pins. The stage has a plurality of holes into which the pins are respectively inserted.

Some of the pins are used for vertically moving a substrate to be processed, which is mounted on the stage, with respect to the top surface of the stage. The other the pins are used for vertically moving a focus ring mounted on the stage with respect to the top surface of the stage.

Patent Document 1: Japanese Patent Application Publication No. 2006-196691

In the above semiconductor manufacturing device, a plurality of driving units for vertically moving the pins is required as many as the number of the pins, so that the device becomes complicated. Further, in the above semiconductor manufacturing device, holes as many as the number of pins need to be formed in the stage. However, it is preferable to form a smaller number of holes in the stage.

SUMMARY OF THE INVENTION

Therefore, in this technical field, a semiconductor manufacturing device capable of vertically moving a substrate to be processed and a focus ring with a small number of pins is required.

A semiconductor manufacturing device in accordance with an aspect of the present invention includes: a processing chamber, a stage, a plurality of pins and a driving unit. The processing chamber defines a processing space. A stage is provided in the processing chamber. The stage has a mounting surface which has a first region for mounting thereon a substrate to be processed and a second region for mounting thereon a focus ring. The stage has a plurality of holes. The pins extend in a direction that intersects the mounting surface while passing through a boundary between the first region and the second region. The second region is disposed to surround the first region. The pins are respectively provided in the holes, each having a first upper end surface and a second upper end surface. The second upper end surface is offset towards the first region with respect to the first upper end surface, and the second end surface is provided above the first upper end surface. The driving unit is configured to vertically move the pins in the extending direction of the holes.

In this semiconductor manufacturing device, the substrate to be processed can be lifted from the mounting surface by moving upward the pins such that only the second upper end surfaces protrude from the mounting surface of the stage. Further, the focus ring can be lifted form the mounting surface by moving upward the pins such that the first upper end surfaces protrude from the mounting surface of the stage. Specifically, each of the pins has an end surface that comes into contact with the substrate and an end surface that comes into contact with the focus ring. Accordingly, in accordance with this semiconductor manufacturing device, the substrate to be processed and the focus ring can be vertically moved with a small number of pins.

In an embodiment, the semiconductor manufacturing device further may include a control unit. The control unit may control, in a first mode, the driving unit to drive the pins such that the second upper end surfaces of the pins protrude beyond the mounting surface and control, in a second mode, the driving unit to drive the pins such that the first upper end surfaces of the pins protrude beyond the mounting surface. In other words, the semiconductor manufacturing device may include a control unit configured to control the driving unit.

In accordance with another aspect of the present invention, there is provided a processing method using the semiconductor manufacturing device. The method includes: (a) mounting the focus ring on the second region; (b) mounting the substrate on the first region; (c) processing the substrate in a state where the substrate is mounted on the first region and the focus ring is mounted on the second region; (d) moving upward the pins such that the second upper end surfaces of the pins protrude beyond the mounting surface of the stage; (e) unloading the substrate, which is lifted up by the pins, from the processing chamber; (f) moving upward the pins such that the first upper end surfaces of the pins protrudes beyond the mounting surface; and (g) unloading the focus ring, which is lifted up by the pins, from the processing chamber.

In accordance with the above processing method, the substrate and the focus ring can be lifted up from the mounting surface with a small number of pins.

In an embodiment, the focus ring and the substrate may be respectively mounted on the second region and the first region by moving downward the pins in a state where the substrate and the focus ring are simultaneously supported by the pins above the mounting surface. Further, after the substrate and the focus ring are lifted up at the same time from the mounting surface by the pins, the substrate may be unloaded and the focus ring may be unloaded.

EFFECT OF THE INVENTION

As described above, in accordance with various aspects of the present invention, there are provided a semiconductor manufacturing device capable of vertically moving a substrate to be processed and a focus ring and a processing method using the semiconductor manufacturing device.

DETAILED DESCRIPTION OF THE EMBODIMENT

Hereinafter, various aspects of an embodiment will be described in detail with reference to the accompanying drawings. Further, like reference numerals are used for like or corresponding parts throughout the drawings.

FIG. 1schematically shows a semiconductor manufacturing device in accordance with an embodiment. InFIG. 1, there is illustrated a cross section of the semiconductor manufacturing device of the present embodiment.FIG. 2is an enlarged cross sectional view of a stage, a plurality of pins and a driving unit of the semiconductor manufacturing device shown inFIG. 1.

As shown inFIG. 1, the semiconductor manufacturing device10of the present embodiment may be a parallel plate type plasma processing apparatus. The semiconductor manufacturing device10includes a processing chamber12. The processing chamber12is formed in a substantially cylindrical shape, which defines a processing space S as its internal space. The semiconductor manufacturing device10has a stage ST in the processing chamber12. In the present embodiment, the stage ST has a table14and an electrostatic chuck50. The table14has a substantially circular plate shape and is provided at a lower portion of the processing space S. The table14is made of, e.g., aluminum, and serves as a lower electrode.

In the present embodiment, the semiconductor manufacturing device10further includes a cylindrical holding portion16and a cylindrical supporting portion17. The cylindrical holding portion16holds the table14while being in contact with the side surface and an edge portion of the bottom surface of the table14. The cylindrical supporting portion17extends from the bottom portion of the processing chamber12in a vertical direction and supports the table14through the cylindrical holding portion16.

The semiconductor manufacturing device10further includes a focus ring18. As shown inFIG. 2, the focus ring18is mounted on a peripheral portion of the top surface of the table14. The focus ring18is a member for improving the in-plane uniformity of the processing accuracy of the substrate W. The focus ring18is a plate-shaped member having a substantial ring shape and may be formed of, e.g., silicon, quartz or silicon carbide.

In the present embodiment, a gas exhaust path20is formed between the sidewall of the processing chamber12and the cylindrical supporting unit17. A baffle plate22is provided at the inlet or in the middle of the gas exhaust path20. Further, a gas exhaust port24is provided at the bottom of the gas exhaust path20. The gas exhaust port24is formed by a gas exhaust pipe28inserted into the bottom portion of the processing chamber12. A gas exhaust unit26is connected to the gas exhaust pipe28. The gas exhaust unit26has a vacuum pump and can decrease a pressure in the processing space S of the processing chamber12to a predetermined vacuum level. A gate valve30for opening/closing a loading/unloading port for the substrate W is provided at the sidewall of the processing chamber12.

A high frequency power supply32for plasma generation is electrically connected to the table14via a matching unit34. The high frequency power supply32applies a high frequency power at a predetermined high frequency (e.g., 13 MHz) to the lower electrode, i.e., the table14.

Further, the semiconductor manufacturing device10has a shower head38in the processing chamber12. The shower head38is provided above the processing space S. The shower head38has an electrode plate40and an electrode holding body42.

The electrode plate40is a substantially circular conductive plate and serves as an upper electrode. A high frequency power supply35for plasma generation is electrically connected to the electrode plate40. The high frequency power supply35applies a high frequency power at a predetermined high frequency (e.g., 60 MHz) to the electrode plate40. When the high frequency power is applied to the table14and the electrode plate40by the high frequency power supplies32and35, a high frequency electric field is generated in the space between the table14and the electrode plate40, i.e., the processing space S.

A plurality of gas holes40is formed in the electrode plate40. The electrode plate40is detachably held by the electrode holding body42. A buffer space42ais provided in the electrode holding body42. The semiconductor manufacturing device10further includes a gas supply unit44which is connected to the gas inlet port25of the buffer space42athrough a gas supply pipe46. The gas supply unit44supplies a processing gas into the processing space S. The processing gas may be, e.g., an etching gas or a film forming gas. A plurality of holes communicating with the gas holes40his formed in the electrode holding body42, and the corresponding holes communicate with the buffer space42a. The gas is supplied to the processing space S from the gas supply unit44through the buffer space42aand the gas holes40h.

In the present embodiment, a magnetic field forming mechanism48extending in a ring shape or a concentric shape is provided at the ceiling portion of the processing chamber12. The magnetic field forming mechanism48is configured to efficiently start high frequency electric discharge (plasma ignition) and stably maintain the electric discharge in the processing space S.

In the semiconductor manufacturing device10, the electrostatic chuck50is provided on the top surface of the table14. As shown inFIG. 2, the electrostatic chuck50includes an electrode52and a pair of insulating films54aand54b. The electrode52is a conductive film and is provided between the insulating films54aand54b. As shown inFIG. 1, a DC power supply56is connected to the electrode52through a switch SW. When a DC voltage is applied from the DC power supply56to the electrode52, a Coulomb force is generated and the substrate W is attracted and held on the electrostatic chuck50by the Coulomb force.

In the present embodiment, the semiconductor manufacturing device10further includes a gas supply line58and a heat transfer gas supply unit62. The heat transfer gas supply unit62is connected to the gas supply line58. The gas supply line58extends to the top surface of the electrostatic chuck50and extends in a ring shape at the top surface. The heat transfer gas supply unit62supplies a heat transfer gas, e.g., He gas, to a gap between the top surface of the electrostatic chuck50and the substrate W.

In the present embodiment, the semiconductor manufacturing device10further includes a control unit66. The control unit66is connected to the gas exhaust unit26, the switch SW, the high frequency power supply32, the matching unit34, the high frequency power supply35, the matching unit36, the gas supply unit44and the heat transfer gas supply unit62. The control unit66transmits a control signal to each of the gas exhaust unit26, the switch SW, the high frequency power supply32, the matching unit34, the high frequency power supply35, the matching unit36, the gas supply unit44and the heat transfer gas supply unit62. The exhaust by the gas exhaust unit26, the opening/closing of the switch SW, the power supply from the high frequency power supply32, the impedance adjustment of the matching unit34, the power supply from the high frequency power supply35, the impedance adjustment of the matching unit36, the supply of the processing gas by the gas supply unit44, and the supply of the heat transfer gas by the heat transfer gas supply unit62are controlled by the control signals from the control unit66.

In this semiconductor manufacturing device10, a processing gas is supplied from the gas supply unit44to the processing space S. Further, a high frequency electric field is formed between the electrode plate40and the table14, i.e., in the processing space S. Accordingly, a plasma is generated in the processing space S, and the substrate W is processed by radicals or the like of elements contained in the processing gas. Moreover, the processing of the substrate W may be any processing, e.g., etching of the substrate W or the film formation on the substrate W. However, it is not limited thereto.

Hereinafter, the configurations of the stage, the pins and the driving unit will be described in detail with reference toFIGS. 1 and 2. The stage ST has a mounting surface PF. The mounting surface PF has a first and a second region R1and R2. The first region R1is a region for mounting thereon the substrate W. In the present embodiment, the first region R1is defined by the top surface of the electrostatic chuck50and has a substantially circular region. The second region R2is a region for mounting thereon the focus ring18, and is formed in a ring shape to surround the first region R1. In the present embodiment, the second region R2is defined by the peripheral portion of the top surface of the table14.

The stage ST has a plurality of holes14h. The holes14hextend in a direction (vertical direction) that intersects the mounting surface PF of the stage ST while passing through a boundary between the first region R1and the second region R1. These holes14hare arranged at a regular interval along the circumferential direction, and the number of the holes14his three or more.

A plurality of pins70is respectively provided in the plurality of holes14h. Each of the pins70has a first and a second upper end surface70aand70b. In the present embodiment, each of the pins70includes a first and a second columnar portion70cand70d. The first columnar portion70cis provided below the second columnar portion70d. The diameter of the first columnar portion70cis greater than that of the second columnar portion70d.

The upper end surface of the first columnar portion70cserves as the first upper end surface70a. The second columnar portion70dextends upward from the upper end surface of the first columnar portion70c. The upper end surface of the second columnar portion70dforms the second upper end surface70b. The central axial line of the second columnar portion70dis offset towards the first region R1with respect to the central axial line of the first columnar portion70c. In other words, the second end surface70bis offset further towards the first region R1with respect to the first upper end surface70a. Accordingly, when the pins70are moved upward, the upper end surface of the second columnar portion70ddoes not come into contact with the focus ring18.

In the present embodiment, a seal member72such as an O-ring or the like is provided between the first columnar portion70cof each pin70and the surface of the table14which defines the hole14hcorresponding to the second columnar portion70c, i.e., the inner surface defining the hole14h. Each of the holes14his sealed by the seal member72. As a result, the airtightness of the processing space S is ensured.

As shown inFIG. 1, each of the pins70is connected to each of a plurality of driving units74. Each of the driving units74generates a driving force for vertically moving, e.g., elevating, the corresponding pin70. Any driving unit for vertically moving the pin70may be employed as the driving unit74. For example, the driving units74may have a hydraulic or a pneumatic cylinder.

The control unit66may be connected to the driving units74. In other words, the vertical movement of the pins72may be controlled by the control signal applied from the control unit66to the driving units74. In the present embodiment, the control unit66controls, in a first mode, the driving units74to drive the pins70such that the second upper end surface70bof each pin70protrudes upward beyond the mounting surface PF. In the first mode, the second upper end surfaces70bof the pins70come into contact with the substrate W, and the substrate W is lifted up from the mounting surface PF (first region R1) by the pins70. The substrate W lifted from the mounting surface PF is unloaded from the processing chamber12through the gate valve30by the transfer unit such as a robot arm or the like.

Further, the control unit66controls, in a second mode, the driving units74to drive the pins70such that the first upper end surface70aof each pin70protrudes upward beyond the mounting surface PF. In the second mode, the first upper end surfaces70aof the pins70come into contact with the focus ring, and the focus ring18is lifted from the mounting surface PF (second region R2) by the pins70. The focus ring18lifted from the mounting surface PF is unloaded to the outside of the processing chamber12through the gate valve30by the transfer unit such as a robot arm or the like.

As described above, in the semiconductor manufacturing device10, each of the pins70has the second upper end surface70bfor upwardly lifting the substrate W and the first upper end surface70afor upwardly lifting the focus ring18. Accordingly, the lifting of the substrate W and the focus ring18from the stage ST can be realized with a small number of pins.

Hereinafter, a processing method using the semiconductor manufacturing apparatus in accordance with the present embodiment will be described.FIG. 3is a flowchart showing a processing method in accordance with an embodiment. The processing method described inFIG. 3may be performed by using the semiconductor manufacturing device10. According to the processing method described inFIG. 3, in a step S1, the focus ring18is to be mounted on the second region R2. In the step S1, the pins70are set in a state of being accommodated in the respective holes14h, i.e., a state in which the second upper end surfaces70bare disposed below the mounting surface PF.

In that state, the focus ring18is guided to a predetermined position in the processing space S, i.e., to a position above the second region R2, through the gate valve30by the transfer unit such as a robot arm or the like. Next, the pins70are moved upward so that the first upper end surfaces70acome into contact with the backside of the focus ring18. Thereafter, the transfer unit is moved to the outside of the processing chamber12and, then, the pins70are moved downward. Accordingly, the focus ring18is mounted on the second region R2.

In a next step S2, a substrate W to be processed is to be mounted on the first region R1. In the step S2, the pins70are set in a state of being accommodated in the respective holes14h, i.e., a state in which the second upper end surfaces70bare disposed below the mounting surface PF. In that state, the substrate W is guided to a predetermined position in the processing space S, i.e., to a position above the first region R1, through the gate valve30by the transfer unit such as a robot arm or the like. Next, the pins70are moved upward so that the second upper end surfaces70bcome into contact with the backside of the substrate W. Thereafter, the transfer unit is moved to the outside of the processing chamber12and, then, the pins70are moved downward. Accordingly, the substrate W is mounted on the first region R1.

In a next step S3, the substrate W is processed. In the step S3, a processing such as plasma etching, film formation or the like is performed in the processing space S.

In a next step S4, the pins70are moved upward so that the second upper end surfaces70bprotrude beyond the mounting surface PF.FIG. 4is a cross sectional view showing the positions of the pins in the step S4. As shown inFIG. 4, in the step S4, the second upper end surfaces70bcome into contact with the backside of the processed substrate W, and the processed substrate W is lifted up from the mounting surface PF (the first region R1) by the pins70. Further, in the step S4, the first upper end surfaces70aare positioned below the mounting surface PF, i.e., below the backside of the focus ring18.

In a next step S5, the processed substrate W is unloaded from the processing chamber12. Specifically, the transfer arm such as a robot arm or the like is moved into the processing chamber12through the gate valve30. Next, the processed substrate W is held by the transfer unit. Thereafter, the pins70are moved downward and, then, the processed substrate W is unloaded to the outside of the processing chamber12by the transfer unit. Further, the steps S2to S5may be executed more than once while exchanging the substrates W.

In a next step S6, in a state where the processed substrate W is unloaded from the processing chamber12, the pins70are moved upward so that the first upper end surfaces70aprotrude beyond the mounting surface PF.FIG. 5is a cross sectional view showing the positions of the pins in the step S6ofFIG. 3. As shown inFIG. 5, in the step S6, the first upper end surfaces70acome into contact with the backside of the focus ring18, and the focus ring18is lifted up from the mounting surface PF (the second region R2) by the pins70.

In a next step S7, the focus ring18is unloaded to the outside of the processing chamber12. Specifically, the transfer arm such as a robot arm or the like is moved into the processing chamber12through the gate valve30. Next, the focus ring18is held by the transfer unit. Thereafter, the pins70are moved downward so as not to interfere with the focus ring18and, then, the focus ring18is unloaded to the outside of the processing chamber12by the transfer unit. Accordingly, the focus ring18that needs to be exchanged can be unloaded from the processing chamber12and, then, the processes from the step S1can be repeated.

Hereinafter, a processing method in accordance with another embodiment which can be performed by using the semiconductor manufacturing device10will be described with reference to FIG6.FIG. 6is a flowchart showing the processing method of another embodiment. According to another embodiment, in a step S1, the pins70are set in a state of being accommodated in the respective holes14h, i.e., a state in which the second upper end surfaces70bare disposed below the mounting surface PF. In that state, the focus ring18is guided to a predetermined position in the processing space S, i.e., to a position above the second region R2, through the gate valve30by the transfer unit such as a robot arm or the like. Further, a substrate W to be processed is guided to another predetermined position, i.e., a position above the first region R1.

Next, the pins70are moved upward so that the first upper end surfaces70acome into contact with the backside of the focus ring18and the second upper end surfaces70bcome into contact with the backside of the substrate W. Then, the transfer unit is moved to the outside of the processing chamber12. At this time, the substrate W to be processed and the focus ring18are simultaneously held by the pins70above the mounting surface PF. Thereafter, the pins70are moved downward. Accordingly, first, in the step S1, the focus ring18is mounted on the second region R2. Next, in a step S2, the substrate W to be processed is mounted on the first region R1by moving further downward the pins70.

According to another embodiment, in a step S3, the substrate W to be processed is processed. After a step S4is executed, a step S6is executed. In other words, in another embodiment, the pins70are moved upward and the processed substrate W is lifted up from the mounting surface PF (the first region R) by the pins70, in the step S4. Further, in the step S6executed after the step S4, the pins70are further moved upward, and the focus ring18is lifted up from the mounting surface PF (the second region R2) by the pins70.FIG. 7is a cross sectional view showing the positions of the pins in the step S6ofFIG. 6. When the step S6ofFIG. 6is executed, the second upper end surfaces70bof the pins70come into contact with the backside of the processed substrate W and the first upper end surfaces70aof the pins70come into contact with the backside of the focus ring18, as shown inFIG. 7. At this time, the processed substrate W and the focus ring18are simultaneously held by the pins70above the mounting surface PF.

Next, steps S5and S7are executed simultaneously. In other words, the transfer unit such a robot arm or the like is moved into the processing chamber12through the gate valve30, and the processed substrate W and the focus ring18are held by the transfer unit. Further, the pins70are moved downward so as not to interfere with the focus ring18and the processed substrate W, and the processed substrate W and the focus ring18are unloaded to the outside of the processing chamber12by the transfer unit. By unloading the processed substrate W and the focus ring18from the processing chamber12in a state where the processed substrate W and the focus ring18simultaneously held by the pins70, the throughput can be improved.

While various embodiments have been described, various modifications may be made without being limited to the above embodiments. For example, the aforementioned semiconductor manufacturing device10is a parallel plate type plasma processing apparatus, but the idea of the aforementioned aspects and embodiments in accordance with the present invention may be applied to a plasma processing apparatus having any plasma generation source. Further, the idea of the aforementioned aspects and embodiments of the present invention are not limited to the plasma processing apparatus and may also be applied to any semiconductor manufacturing device for mounting a substrate W to be processed and a focus ring on a stage in a processing space and processing the substrate W.

DESCRIPTION OF REFERENCE NUMERALS