Substrate processing apparatus

Abstract

The present invention relates to a substrate processing apparatus and a substrate processing method, and more specifically, to a substrate processing apparatus capable of etching one or more thin films on a substrate having two or more heterogeneous films deposited on its lower surface.

Description

Technology Field

[0001] The present invention relates to a substrate processing apparatus, and more specifically, to a substrate processing apparatus capable of etching one or more thin films on a substrate having two or more heterogeneous films deposited on its lower surface. Background Technology

[0002] A general substrate processing device deposits a thin film of a predetermined thickness on one side of a substrate, for example, on the upper surface of the substrate. In this case, when the thin film is deposited in an overlapping manner on the upper surface of the substrate, the substrate can be bowed by the stress of the thin film.

[0003] When the substrate bows in this manner, it becomes difficult to position the substrate correctly during subsequent various substrate processing steps. In particular, as the precision of substrate processing steps increases day by day, this bowing phenomenon reduces the precision of the processing steps. Therefore, to prevent the aforementioned bowing phenomenon of the substrate, a thin film of a predetermined thickness is deposited on the lower surface of the substrate to prevent the bowing phenomenon.

[0004] In this case, since the direction of stress acting on the substrate may differ, two or more heterogeneous films may be deposited on the underside of the substrate. As such, thin films deposited on the underside of the substrate become unnecessary in subsequent processes and may need to be removed through etching or the like. The problem to be solved

[0005] The present invention aims to provide a substrate processing apparatus capable of etching one or more thin films from the bottom while leaving some thin films intact on a substrate having two or more heterogeneous films deposited on the bottom surface, in order to solve the above-mentioned problems.

[0006] In addition, the present invention aims to provide a substrate processing apparatus in which an etching process can be carried out in a single chamber when etching a thin film of a substrate having two or more heterogeneous films deposited on its lower surface. means of solving the problem

[0007] The objective of the present invention as described above can be achieved by a substrate processing apparatus comprising: a chamber providing a processing space for a substrate; an upper shower head providing purge gas toward the upper surface of the substrate and heating the substrate to a first temperature; a first RF power source providing RF power to the upper shower head; a substrate holder supporting the edge of the substrate; and a lower shower head providing process gas toward the lower surface of the substrate and heating the substrate to a second temperature, and configured to be movable relative to the substrate holder in a vertical direction, wherein when the substrate holder and the lower shower head move relative to each other in a vertical direction, the lower surface of the substrate is heat-conductively seated on the upper surface of the lower shower head.

[0008] In addition, the lower shower head is provided on the inner side of the substrate holder, and a stepped portion is formed on the edge of the lower shower head to accommodate the substrate holder, so that the substrate holder can be provided to descend below the upper surface of the lower shower head.

[0009] Here, the height of the step portion can be formed to be greater than or equal to the thickness of the substrate holder.

[0010] In addition, the lower shower head may comprise a first lower shower head plate that supplies process gas toward the lower surface of the substrate, and a second lower shower head plate disposed below the first lower shower head plate.

[0011] In this case, the lower shower head further comprises a lower plate, a buffer space is formed between the lower plate and the second lower shower head plate, and a plasma space in which plasma is generated can be formed between the second lower shower head plate and the first lower shower head plate.

[0012] Here, a second RF power source providing RF power to the lower shower head is further provided, and the second RF power source can be connected to the second lower shower head plate. Effects of the invention

[0013] According to the present invention having the above-described configuration, on a substrate having two or more heterogeneous films deposited on the lower surface, it is possible to etch only one or more films from the bottom while leaving some of the films intact.

[0014] In addition, according to the present invention, when etching a thin film of a substrate having two or more heterogeneous films deposited on its lower surface, the etching process can be carried out in a single chamber, thereby reducing the installation area of ​​the device. Brief explanation of the drawing

[0015] FIG. 1 is a side view of a substrate processing apparatus according to one embodiment of the present invention, FIG. 2 is a side view illustrating the case where only the lower shower head is raised by the first lifting / lowering unit, FIG. 3 is a side view illustrating a state in which the lower shower head is tilted in one direction relative to the substrate by the first tilting unit, FIG. 4 is a side view showing the state in which both the substrate support and the lower shower head are raised by the second lifting / lowering unit. FIG. 5 is a side view showing the state in which both the substrate support and the lower shower head are tilted by the second tilting unit. FIG. 6 is a perspective view of the second tilting drive unit of the substrate processing device, FIG. 7 is a cross-sectional view along the line 'VII-VII' of FIG. 6, FIG. 8 is a flowchart illustrating a substrate processing method according to the present invention, FIG. 9 is a schematic diagram illustrating an etching step according to the present invention. Figure 10 is a graph showing the wavelengths emitted from a thin film deposited on the lower surface of a substrate. Specific details for implementing the invention

[0016] Hereinafter, the structure of a substrate processing apparatus and a substrate processing method according to an embodiment of the present invention will be examined in detail with reference to the drawings.

[0017] FIG. 1 is a side view of a substrate processing device (1000) according to one embodiment of the present invention.

[0018] Referring to FIG. 1, the substrate processing device (1000) may comprise a chamber (300) that provides a processing space (310) for a substrate (S), an upper shower head (200) that provides purge gas toward the upper surface of the substrate (S) and heats the substrate (S) to a first temperature, a first RF power source (225) that provides RF power to the upper shower head (200), a substrate holder (410) that supports the edge of the substrate (S), and a lower shower head (420) that provides process gas toward the lower surface of the substrate (S), heats the substrate (S) to a second temperature, and is configured to be movable relative to the substrate holder (410) in a vertical direction. Additionally, the substrate processing device (1000) may comprise a second RF power source (485) that provides RF power to the lower shower head (420).

[0019] Specifically, the chamber (300) can provide a processing space (310) inside which various components required for processing the substrate (S), etc., are accommodated.

[0020] One side of the chamber (300) may be provided with an opening (not shown) through which the substrate (S) is introduced into or removed from the processing space (310), and a door (not shown) may be provided in the aforementioned opening.

[0021] Meanwhile, an upper supply channel (220) through which purge gas is supplied may be connected to the upper part of the chamber (300).

[0022] The purge gas supplied along the upper supply channel (220) can be supplied to the lower part through the upper shower head (200).

[0023] The upper shower head (200) is provided at the top of the chamber (300) and can supply a purge gas, such as an inert gas, toward the upper surface of the substrate (S) and heat the substrate (S) to a first temperature.

[0024] For example, the upper shower head (200) may be equipped with an upper heater (240) that heats the substrate (S) and an upper shower head plate (230) connected to the lower part of the upper heater (240). In FIG. 1, the upper heater (240) is shown separately from the upper shower head plate (230), but it may be formed integrally.

[0025] The purge gas supplied from the upper shower head (200) is supplied toward the lower processing space (310) to prevent the process gas supplied from the lower shower head (420) from flowing into the upper shower head (200).

[0026] Specifically, the upper shower head (200) may provide a first buffer space (210). The first buffer space (210) may be provided between the upper heater (240) and the upper shower head plate (230).

[0027] The purge gas supplied through the upper supply channel (220) can be diffused in the first buffer space (210) and supplied to the lower part through the first supply hole (212) of the upper shower head plate (230).

[0028] Meanwhile, a first RF power source (225) providing RF power may be connected to the upper shower head (200). The first RF power source (225) may be connected, for example, to the upper shower head plate (230).

[0029] When the upper shower head (200) acts as the upper electrode, the lower shower head (420) can be grounded to act as the lower electrode.

[0030] When an RF power source is applied to the upper shower head (200) during the process on the substrate (S), the upper shower head (200) is capacitively coupled with the lower shower head (420), and a direct plasma is generated between the upper shower head (200) and the lower shower head (420), thereby allowing the process on the lower surface of the substrate (S) to proceed smoothly.

[0031] Meanwhile, the substrate support member (400) is provided so as to be movable up and down at the bottom of the processing space (310) and can support the edge of the lower surface of the substrate (S). The lower shower head (420) is provided inside the substrate support member (400), and process gas can be supplied toward the lower surface of the substrate (S) by the lower shower head (420).

[0032] The above substrate support member (400) may be provided with a substrate holder (410) that supports the edge of the lower surface of the substrate, and an extension member (411) that is connected to the lower end of the substrate holder (410) and extends downward. The lower shower head (420) that supplies process gas toward the lower surface of the substrate (S) may be disposed inside the substrate holder (410).

[0033] The above substrate holder (410) is formed to extend upward from the extension part (411), and the upper end of the substrate holder (410) may have a shape that is bent inward.

[0034] In this case, a recess (416) may be formed in the upper portion of the substrate holder (410). Accordingly, when the substrate (S) is placed on the substrate holder (410), the substrate (S) can be inserted into the recess (416) to support the lower surface of the edge of the substrate (S).

[0035] Additionally, the substrate holder (410) may be configured in a cylindrical shape in which the side wall surrounds the entire side perimeter of the lower shower head (420), or it may be configured in the form of a plurality of columns spaced apart around the side perimeter of the lower shower head (420), although not shown in the drawing.

[0036] Meanwhile, the lower shower head (420) may be equipped with a first lower shower head plate (430) that supplies process gas toward the lower surface of the substrate (S), and a second lower shower head plate (440) disposed below the first lower shower head plate (430).

[0037] The lower shower head (420) may further be provided with a lower plate (450) having a heat exchange channel (not shown) formed therein, and the second lower shower head plate (440) may be positioned on the upper part of the lower plate (450). Furthermore, the lower shower head (420) may be provided with a drive bar (470) extending downward.

[0038] In the above configuration, a second buffer space (442) may be provided in the lower shower head (420). For example, the second buffer space (442) may be provided between the lower plate (450) and the second lower shower head plate (440).

[0039] Additionally, a plasma space (432) in which plasma is generated may be provided between the second lower shower head plate (440) and the first lower shower head plate (430).

[0040] In this case, a second RF power source (485) providing RF power may be connected to the lower shower head (420). The second RF power source (485) may be connected, for example, to the second lower shower head plate (440).

[0041] In addition, in the present embodiment, the first RF power source (225) and the second RF power source (485) are shown separately, but are not limited thereto, and a single RF power source (not shown) may be provided and RF power may be selectively applied to the upper shower head (200) and the lower shower head (420) by a switching device.

[0042] Meanwhile, a stepped portion (431) on which the substrate holder (410) can be seated may be formed at the edge of the lower shower head (420).

[0043] That is, as described below, when the substrate holder (410) and the lower shower head (420) move relative to each other in a vertical direction, the edge of the substrate holder (410) can be seated on the stepped portion (431).

[0044] For example, the step portion (431) may be formed along the upper edge of the first lower shower head plate (430).

[0045] When the edge of the substrate holder (410) is seated on the stepped portion (431), the lower surface of the substrate (S) can be seated on the upper surface of the first lower shower head plate (430) so as to conduct heat. That is, the height of the stepped portion (431) can be formed to be greater than or equal to the thickness of the substrate holder (410).

[0046] In this configuration, when the substrate holder (410) is lowered, the substrate holder (410) can be lowered below the upper surface of the lower shower head (420). That is, the substrate holder (410) can be lowered below the upper surface of the first lower shower head plate (430).

[0047] Accordingly, when the substrate holder (410) is seated on the stepped portion (431), the lower surface of the substrate (S) can be seated on the upper surface of the first lower shower head plate (430). When the lower surface of the substrate (S) is seated on the upper surface of the first lower shower head plate (430), the temperature of the substrate (S) can be lowered to a second temperature by the temperature of the first lower shower head plate (430), which is relatively low. This will be described in detail later.

[0048] Meanwhile, when process gas is supplied to the first lower shower head plate (430) through the lower supply path (not shown) penetrating the drive bar (470), the process gas can be diffused in the second buffer space (442).

[0049] Additionally, when RF power is applied to the second lower shower head plate (440), the process gas passing through the second lower shower head plate (440) can generate plasma in the plasma space (432) and be supplied toward the lower surface of the substrate (S) in the form of remote plasma through the first lower shower head plate (430).

[0050] Additionally, the lower plate (450) may serve to support the first lower shower head plate (430). In this case, the first lower shower head plate (430) may be connected to the lower plate (450).

[0051] In this case, when the lower end of the extension part (411) and the lower end of the drive bar (470) protrude through the lower part of the chamber (300), a first bellows (900) that wraps around the lower end of the extension part (411) and the lower end of the drive bar (470) may be provided.

[0052] The upper portion of the first bellows (900) is connected to the lower surface of the chamber (300), and the lower portion of the first bellows (900) can be connected to the second lifting / lowering plate (610) described later.

[0053] Meanwhile, the space between the side of the first lower shower head plate (430), the side of the lower plate (450), and the inner surface of the substrate holder (410) can form an exhaust passage (422).

[0054] In this case, some of the process gas supplied from the first lower shower head plate (430) is discharged to the lower part of the chamber (300) through the exhaust passage (422) and the opening (412) of the extension (411), and can be exhausted to the outside of the chamber (300) through the exhaust part (490) provided at the bottom of the chamber (300).

[0055] Meanwhile, the purge gas supplied from the upper shower head (200) toward the lower part can flow to the lower part of the chamber (300) and be discharged to the outside of the chamber (300) through the exhaust part (490).

[0056] Meanwhile, in the case of a device that supplies process gas toward the lower surface of a substrate (S), such as the substrate processing device (1000) according to the present invention, the distance between the substrate (S) and the upper shower head (200) and the distance between the substrate (S) and the first lower shower head plate (430) are important. This is because, when using plasma, it is necessary to adjust the gap between the substrate (S) and the upper shower head (200) so that plasma is not generated between the substrate (S) and the upper shower head (200). In addition, when supplying process gas toward the lower surface of the substrate (S), the gap between the substrate (S) and the first lower shower head plate (430) also becomes important.

[0057] Furthermore, as described below, when one or more thin films are etched from the bottom while leaving some thin films intact on a substrate (S) on which two or more heterogeneous films are deposited on the bottom surface, it is necessary to lower the temperature of the substrate (S) before performing the second etching step following the first etching step. When performing these first and second etching steps in a single chamber (300), a step of lowering the temperature of the substrate is required between the first etching step and the second etching step.

[0058] To this end, in the case of the substrate processing device (1000) according to the present invention, the substrate holder (410) and the lower shower head (420) can be moved relative to each other in a vertical direction so that the lower surface of the substrate (S) is placed on the upper surface of the lower shower head (420), more precisely, on the upper surface of the first lower shower head plate (430). When the lower surface of the substrate (S) is placed on the upper surface of the first lower shower head plate (430), which has a relatively low temperature, the temperature of the substrate (S) can be lowered by heat conduction.

[0059] Additionally, due to various factors, the substrate (S), the upper shower head (200), and the substrate (S) and the first lower shower head plate (430) may not be arranged parallel to each other, so it may be necessary to align them parallel. On the other hand, during the process for the substrate (S), it may be necessary to intentionally arrange the substrate (S), the upper shower head (200), and the substrate (S) and the first lower shower head plate (430) so that they are not parallel. In this case, it is necessary to tilt the substrate (S) relative to the upper shower head (200) or to tilt the first lower shower head plate (430) relative to the substrate (S).

[0060] In order to adjust the tilting and / or distance as described above, the present invention may be provided with a first lifting / lowering unit (750) that raises and lowers the lower shower head (420) to adjust the gap between the substrate (S) and the lower shower head (420), a first tilting unit (700) that tilts the lower shower head (420) relative to the substrate (S), a second lifting / lowering unit (600) that raises and lowers the substrate support part (400) and the lower shower head (420) to adjust the gap between the substrate (S) and the upper shower head (200), and a second tilting unit (500) that tilts the substrate support part (400) and the lower shower head (420) to tilt the substrate (S) relative to the upper shower head (200).

[0061] First, we will examine the components provided at the bottom of the chamber (300), and then examine the first lifting / lowering unit (750), the first tilting unit (700), the second lifting / lowering unit (600), and the second tilting unit (500).

[0062] A second tilting housing (110) is connected to the lower part of the chamber (300), and a second tilting plate (510) can be tiltably connected to the second tilting housing (110). In this case, a second tilting drive unit (120) can be connected to the second tilting housing (110).

[0063] Specifically, one side of the second tilting plate (510) is connected to the second tilting housing (110), and the other side of the second tilting plate (510) is connected to the second tilting connection part (520). The second tilting connection part (520) may be provided with a second support bar (522) connected to the lower part of the chamber (300) and a second pivot part (524) connected to the end of the second support bar (522). The second pivot part (524) may be formed in a spherical, semicircular, or curved shape, and the pivot part (524) may be rotatably connected to the upper end of the second vertical connection bar (540) described later. Accordingly, when the second tilting drive unit (120) is driven so that one side of the second tilting plate (510) moves up and down, the entire second tilting plate (510) can be tilted by rotating around the second tilting connection unit (520).

[0064] Additionally, an opening (512) is formed in the second tilting plate (510), and the lower end of the driving bar (470) and the extension part (411) can pass through the opening (512).

[0065] Meanwhile, a second vertical connecting bar (540) may be arranged and connected along the vertical direction at the lower side of the second tilting plate (510). A second lifting plate (610), to which the lower end of the substrate support part (400) or the lower end of the extension part (411) of the substrate support part (400) is connected, may be connected to the second vertical connecting bar (540) so as to be able to be raised and lowered.

[0066] That is, the second lifting / lowering plate (610) can move up and down along the second vertical connecting bar (540). To this end, a linear motion (LM) drive unit (not shown) may be placed on the inner side of the second vertical connecting bar (540), and a second lifting / lowering drive unit (810) may be connected to the second vertical connecting bar (540). Accordingly, the LM drive unit is driven by the driving of the second lifting / lowering drive unit (810), so that the second lifting / lowering plate (610) can move up and down along the second vertical connecting bar (540).

[0067] Additionally, an opening (612) is formed in the second lifting / lowering plate (610), so that the driving bar (470) of the lower shower head (420) can be positioned through the opening (612).

[0068] Meanwhile, a second bellows (910) may be provided between the second lifting / lowering plate (610) and the first lifting / lowering plate (760) described later. That is, the second bellows (910) may be positioned between the second lifting / lowering plate (610) and the first lifting / lowering plate (760) while wrapping around the lower end of the drive bar (470).

[0069] Furthermore, a first tilting housing (630) is connected to the lower side of the other side of the second lifting / lowering plate (610), and a first tilting plate (710) can be tiltably connected to the first tilting housing (630). In this case, a first tilting drive unit (620) can be connected to the first tilting housing (630).

[0070] Specifically, the other side of the first tilting plate (710) is connected to the first tilting housing (630), and one side of the first tilting plate (710) is connected to the first tilting connection part (640). The first tilting connection part (640) may be provided with a first support bar (642) connected to the lower part of the second lifting / lowering plate (610) and a first pivot part (644) connected to the end of the first support bar (642). The first pivot part (644) is formed in a spherical, semicircular, or curved shape and is connected to one side of the first tilting plate (710). Accordingly, when the first tilting drive unit (620) is driven, the other side of the first tilting plate (710) moves up and down, and the entire first tilting plate (710) can be tilted by rotating around the first tilting connection unit (640).

[0071] Additionally, a first vertical connecting bar (740) may be arranged and connected along the vertical direction on one side of the lower portion of the first tilting plate (710). A first lifting plate (760), to which the driving bar (470) of the lower shower head (420) is connected, may be connected to the first vertical connecting bar (740) so as to be able to be raised and lowered.

[0072] That is, the first lifting / lowering plate (760) can move up and down along the first vertical connecting bar (740). To this end, a linear motion (LM) drive unit (not shown) may be placed on the inner side of the first vertical connecting bar (740), and a first lifting / lowering drive unit (820) may be connected to the first vertical connecting bar (740). Accordingly, the LM drive unit is driven by the driving of the first lifting / lowering drive unit (820), so that the first lifting / lowering plate (760) can move up and down along the first vertical connecting bar (740).

[0073] Additionally, an opening (714) is formed in the first tilting plate (710), so that the driving bar (470) of the lower shower head (420) can be positioned through the opening (714).

[0074] Furthermore, an additional opening (712) is formed in the first tilting plate (710), so that the second vertical connecting bar (540) can be positioned through the additional opening (712).

[0075] Meanwhile, the first vertical connecting bar (740) and the second vertical connecting bar (540) can be symmetrically arranged around the drive bar (470). This overcomes the spatial constraints required to install the first vertical connecting bar (740) and the second vertical connecting bar (540), and furthermore, when the first lifting / lowering drive unit (820) and the second lifting / lowering drive unit (810) are driven, the driving force is distributed, thereby reducing the load acting on the first vertical connecting bar (740) and the second vertical connecting bar (540), respectively.

[0076] Let us examine the operation of the first lifting / lowering unit (750), the first tilting unit (700), the second lifting / lowering unit (600), and the second tilting unit (500) in the above configuration.

[0077] FIG. 2 is a side view illustrating the case where only the lower shower head (420) is raised by the first lifting / lowering unit (750).

[0078] Referring to FIG. 2, the first lifting / lowering unit (750) may be equipped with a first lifting / lowering plate (760) connected to a drive bar (470) of the lower shower head (420), and a first lifting / lowering drive unit (820) for lifting / lowering the first lifting / lowering plate (760).

[0079] In this case, the first lifting / lowering drive unit (820) is connected to the first vertical connecting bar (740) as described above, and the first lifting / lowering plate (760) can be lifted / lowered along the first vertical connecting bar (740).

[0080] Accordingly, when the first lifting / lowering drive unit (820) is driven, the LM drive unit provided on the inner side of the first vertical connecting bar (740) is driven, so that the first lifting / lowering plate (760) can be moved up and down along the first vertical connecting bar (740).

[0081] As a result, as shown in FIG. 2, the lower shower head (420) is raised and lowered, thereby allowing the gap or distance between the lower surface of the substrate (S) and the first lower shower head plate (430) to be adjusted.

[0082] In particular, when the lower shower head (420) is raised and the substrate holder (410) is inserted into the stepped portion (431) of the lower shower head (420), the lower surface of the substrate (S) can come into contact with the upper surface of the first lower shower head plate (430). This is possible because the height of the stepped portion (431) is formed to be greater than or equal to the thickness of the substrate holder (410).

[0083] Meanwhile, FIG. 3 is a side view illustrating the state in which the lower shower head (420) is tilted in one direction relative to the substrate (S) by the first tilting unit (700).

[0084] Referring to FIG. 3, the first tilting unit (700) may be equipped with a first tilting plate (710) connected to a drive bar (470) of the lower shower head (420), and a first tilting drive unit (620) that tilts the first tilting plate (710).

[0085] In addition, the first tilting drive unit (620) can be connected to the second lifting / lowering plate (610) by the first tilting housing (630) as described above.

[0086] Additionally, the drive bar (470) of the lower shower head (420) can be positioned to pass through the opening (612) of the second lifting / lowering plate (610).

[0087] In this case, the first tilting plate (710) can be connected to the first lifting plate (760), which is connected to the lower end of the driving bar (470) of the lower shower head (420) by the first vertical connecting bar (740) as described above.

[0088] Accordingly, when the first tilting drive unit (620) is driven while the first lifting / lowering plate (760) is fixed to the first vertical connecting bar (740), the first tilting plate (710) can be tilted by rotating around the aforementioned first tilting connecting unit (640), and the first lifting / lowering plate (760) can also be tilted by rotating together.

[0089] Accordingly, as shown in FIG. 3, the lower shower head (420) can rotate in one direction, for example, clockwise, and the first lower shower head plate (430) can be tilted relative to the lower surface of the substrate (S) so that the gap (G2, G3) between the upper surface of the first lower shower head plate (430) and the lower surface of the substrate (S) can vary depending on the area.

[0090] Meanwhile, FIG. 4 is a side view illustrating a state in which both the substrate support (400) and the lower shower head (420) are raised by the second lifting / lowering unit (600). In this case, the substrate support (400) and the lower shower head (420) may be raised to a process height in order to etch the thin film on the lower surface of the substrate (S).

[0091] Referring to FIG. 4, the second lifting / lowering unit (600) may be equipped with a second lifting / lowering plate (610) connected to the lower end of the substrate support (400) and the driving bar (470) of the lower shower head (420), and a second lifting / lowering driving unit (810) for lifting / lowering the second lifting / lowering plate (610).

[0092] In this case, as described above, the drive bar (470) of the lower shower head (420) is connected to the first lifting plate (760), and the first lifting plate (760) is connected to the first vertical connecting bar (740). Additionally, the first vertical connecting bar (740) is connected to one side of the first tilting plate (710), and the first tilting plate (710) and the second lifting plate (610) are connected by the first tilting housing (630).

[0093] Accordingly, the lower end of the extension part (411) of the substrate support part (400) is directly connected to the second lifting / lowering plate (610), and the driving bar (470) of the lower shower head (420) is indirectly connected so that they can be lifted / lowered together.

[0094] Furthermore, the second lifting / lowering drive unit (810) is connected to the second vertical connecting bar (540), and the second lifting / lowering plate (610) can be lifted / lowered along the second vertical connecting bar (540).

[0095] Accordingly, the LM drive unit provided on the inner side of the second vertical connecting bar (540) is driven by the driving of the second lifting / lowering drive unit (810), and thereby the second lifting / lowering plate (610) is raised / lowered along the second vertical connecting bar (540).

[0096] As shown in FIG. 4, the substrate support (400) and the lower shower head (420) move up and down together to adjust the gap or distance (G4) between the upper surface of the substrate (S) and the upper shower head (200).

[0097] Meanwhile, FIG. 5 is a side view showing the state in which both the substrate support (400) and the lower shower head (420) are tilted by the second tilting unit (500).

[0098] Referring to FIG. 5, the second tilting unit (500) may be equipped with a second tilting plate (510) connected to the lower end of the substrate support (400) and the driving bar (470) of the lower shower head (420), and a second tilting driving unit (120) that tilts the second tilting plate (510).

[0099] In this case, as described above, the other side of the second tilting plate (510) is connected to the second vertical connecting bar (540), and the second lifting plate (610), which is connected to the lower end of the substrate support (400), is connected to the second vertical connecting bar (540). In addition, the driving bar (470) of the lower shower head (420) is connected to the first lifting plate (760), and the first lifting plate (760) is connected to the first vertical connecting bar (740) so as to be able to lift and lower. Furthermore, one side of the first tilting plate (710) is connected to the first vertical connecting bar (740), and the other side of the first tilting plate (710) is connected to the other side of the second lifting plate (610) by the first tilting housing (630).

[0100] Accordingly, when the second tilting drive unit (120) is driven, the second tilting plate (510) can be tilted by rotating around the second tilting connection unit (520), and the substrate support unit (400) and the lower shower head (420) can also be tilted together.

[0101] Accordingly, as shown in FIG. 5, the substrate support (400) and the lower shower head (420) can both rotate in one direction, for example, clockwise, and the substrate (S) can be tilted relative to the lower surface of the upper shower head (200) so that the gap (G5, G6) between the lower surface of the upper shower head (200) and the upper surface of the substrate (S) can vary depending on the area.

[0102] Meanwhile, FIGS. 6 and 7 correspond to drawings explaining the operation of the aforementioned tilting drive unit. FIGS. 6 and 7 focus on the aforementioned second tilting drive unit (120), and since the first tilting drive unit (620) has the same structure as the second tilting drive unit (120), a repetitive explanation is omitted.

[0103] FIG. 6 is a perspective view of the second tilting drive unit (120) of the substrate processing device (1000).

[0104] Referring to FIG. 6, the substrate processing device (1000) may be equipped with a first adjustment unit (102) that rotates the second tilting plate (510) up and down by a predetermined distance, and a second adjustment unit (104) that prevents the second tilting plate (510) from moving upward due to the negative pressure inside the chamber (300).

[0105] That is, the first adjustment unit (102) rotates one side of the second tilting plate (510) up and down to adjust the rotation angle of the second tilting plate (510).

[0106] As shown in FIG. 6, the first adjustment unit (102) is provided in a second tilting housing (110) connected to the lower part of the chamber (300). The second tilting housing (110) is fixed to the lower part of the chamber (300) and has a groove (112) formed into which one side of the second tilting plate (510) is inserted. With one side of the second tilting plate (510) inserted into the groove (112), the first adjustment unit (102) described above causes one side of the second tilting plate (510) to rotate slightly up and down, or the second adjustment unit (104) prevents the second tilting plate (510) from rising and fixes the height of the second tilting plate (510).

[0107] Figure 7 is a cross-sectional view along the line 'VII-VII' of Figure 6.

[0108] Referring to FIG. 7, the first adjustment unit (102) has a second tilting drive unit (120) having a cam member (130) that applies a predetermined force to the second tilting plate (510) and a rotation axis (122) that rotates the cam member (130) by being connected to the cam member (130) at a predetermined distance from the rotation center of the cam member (130).

[0109] A second tilting drive unit (120), such as a motor, is provided in the second tilting housing (110), and a rotation axis (122) extending from the second tilting drive unit (120) is connected to the cam member (130). At this time, the rotation center of the cam member (130) and the rotation axis (122) of the second tilting drive unit (120) are connected at a distance (d). In FIG. 7, line ⓐ is a virtual line extending from the center of the rotation axis (122) of the second tilting drive unit (120), and line ⓑ corresponds to a virtual line extending from the rotation center of the cam member (130).

[0110] That is, the rotation axis (122) of the second tilting drive unit (120) is not connected to the rotation center of the cam member (130), but rather the rotation axis (122) of the second tilting drive unit (120) is connected to a point spaced apart from the rotation center of the cam member (130) by a predetermined distance. In such a structure, when the rotation axis (122) rotates by the driving of the second tilting drive unit (120), the cam member (130) also rotates in conjunction.

[0111] In this case, since the center of rotation of the cam member (130) is positioned apart from the center of the rotation axis (122), when the cam member (130) rotates, the outer circumference of the cam member (130) changes in distance from the rotation axis (122). That is, when the cam member (130) rotates, the outer circumference of the cam member (130) does not form a constant circular trajectory, but rather forms an irregular trajectory in which the distance from the rotation axis (122) changes. Therefore, when the distance between the outer circumference of the cam member (130) and the rotation axis (122) becomes relatively far, the second tilting plate (510) can be raised upward and rotated, and conversely, when the distance between the outer circumference of the cam member (130) and the rotation axis (122) becomes relatively short, the second tilting plate (510) descends downward and rotates.

[0112] At this time, a bearing part (140) may be further provided between the cam member (130) and the second tilting plate (510), which surrounds the outer circumference of the cam member (130) and applies a predetermined force to the second tilting plate (510). The bearing part (140) prevents the cam member (130) from directly contacting the push bar (150) described later, thereby preventing wear of the cam member (130) or the push bar (150).

[0113] Furthermore, the above substrate processing device (1000) may further be provided with a push bar (150) having one end in contact with the outer circumference of the bearing part (140) and applying a predetermined force to the second tilting plate (510) by the rotation of the bearing part (140).

[0114] The push bar (150) is provided to be movable up and down by passing through a linear bush (160) that passes through an opening (114) provided on the other side of the second tilting housing (110). When the push bar (150) moves up and down by the rotation of the cam member (130), the linear bush (160) guides the up and down movement of the push bar (150). Accordingly, when the bearing part (140) rotates together with the rotation of the cam member (130), the push bar (150) moves up and down to raise and lower the second tilting plate (510) and rotate it.

[0115] Additionally, the push bar (150) supports the second tilting plate (510) to prevent sagging of the second tilting plate (510). That is, when the cam member (130) does not rotate, the cam member (130) is fixed by engaging with the rotation axis (122), so the height of the upper part of the push bar (150) is fixed to support the second tilting plate (510) and prevent sagging.

[0116] Meanwhile, a reduction gear (124) may be positioned between the cam member (130) and the rotation shaft (122). The reduction gear (124) reduces the rotational force of the rotation shaft (122) and transmits it to the cam member (130). In this case, the reduction ratio of the reduction gear (124) may be determined in correspondence with the maximum distance at which the second tilting plate (510) can be raised and lowered.

[0118] Hereinafter, we will examine the process of etching a thin film deposited on the lower surface of a substrate (S) by a substrate processing device (1000) having the configuration described above.

[0119] As described above, a thin film may be deposited on the lower surface of the substrate (S) to alleviate bending or bowing of the substrate (S). In this case, since the direction of stress acting on the substrate (S) may differ, two or more heterogeneous films (12, 14) (see FIG. 9) may be deposited on the lower surface of the substrate (S). The thin film deposited on the lower surface of the substrate (S) in this manner may become unnecessary in subsequent processes and may need to be removed through etching, etc. Hereinafter, the present invention will examine a substrate processing method for etching the thin film of the substrate (S) on which two or more heterogeneous films (12, 14) are deposited on the lower surface.

[0120] FIG. 8 is a flowchart illustrating a substrate processing method according to the present invention.

[0121] Referring to FIG. 8, the substrate processing method may include a step (S110) of placing the substrate (S) on the substrate holder (410), a first etching step (S130) of etching the thin film (14) of the substrate (S) at a first temperature, and a second etching step (S150) of etching the thin film (14) of the substrate (S) at a second temperature.

[0122] Here, two or more heterogeneous films (12, 14) may be deposited on the lower surface of the substrate (S).

[0123] The thin film deposited on the lower surface of the substrate (S) may be composed of, for example, an oxide film, polycrystalline silicon, nitride, metal, or photoresist. Additionally, the photoresist may be composed of MOR (Metal Organic Resist), etc.

[0124] When two types of thin films are deposited on the lower surface of the substrate (S), a first thin film (12) may be deposited on the lower surface of the substrate (S), and a second thin film (14) may be deposited on the lower surface of the first thin film (12).

[0125] In this case, the first thin film (12) may be composed of, for example, an oxide film (SiO2), and the second thin film (14) may be composed of polysilicon, nitride (Si3N4), a metal, or a photoresist. Alternatively, the first thin film (12) may be composed of polysilicon, and the second thin film (14) may be composed of nitride, a metal, or a photoresist. However, the types of such thin films are described as examples and are not limited thereto.

[0126] Below, we will examine a method for etching only the second thin film (14) while leaving the first thin film (12) intact, in the case where the first thin film (12) is composed of an oxide film (SiO2) and the second thin film (14) is composed of a nitride (Si3N4).

[0127] However, the present invention is not limited thereto and can be implemented in various forms depending on the number of thin films, such as, for example, when three or more thin films are deposited on the lower surface of a substrate (S), etching two thin films at the bottom and leaving one thin film, or etching the bottommost film at the bottom and leaving two thin films.

[0128] FIG. 9 is a schematic diagram illustrating an etching step according to the present invention. FIG. 9 illustrates a side view of the substrate (S). FIG. 9 (A) illustrates the state before etching the substrate (S), that is, the state in which two types of thin films are deposited on the lower surface of the substrate (S); FIG. 9 (B) illustrates the case where the first etching step is performed; and FIG. 9 (C) illustrates the case where the second etching step is performed.

[0129] Referring to FIGS. 8 and 9, the etching of the second thin film (14) on the lower surface of the substrate (S) can be performed in two steps.

[0130] That is, in the case of the first etching step, the first etching amount of the second thin film (14) of the substrate (S) can be increased so that a large amount of the second thin film (14) can be etched. In the case of the first etching step, one or more of CF4, SF6, CH2F2, NF3, NH3, O2, and F2 can be supplied through the lower shower head (420), and N2, Ar, or He gas can be supplied through the upper shower head (200).

[0131] For example, the first etching amount of the second thin film (14) of the substrate (S) in the first etching step may be greater than the second etching amount of the second thin film (14) of the substrate (S) in the second etching step.

[0132] Additionally, the first selectivity ratio of the second thin film (14) of the substrate (S) in the first etching step may be smaller than the second selectivity ratio of the second thin film (14) of the substrate (S) in the second etching step. That is, the second selectivity ratio of the second thin film (14) of the substrate (S) in the second etching step may be larger than the first selectivity ratio of the second thin film (14) of the substrate (S) in the first etching step.

[0133] For example, in the first etching step above, the etching rate may be approximately 300 Å / s or higher, and the selectivity ratio may be approximately 2 or lower.

[0134] Ultimately, the first etching step above may correspond to a process of increasing the etching amount of the second thin film (14) rather than the selectivity.

[0135] The first etching step described above can be performed at a relatively high temperature. That is, the first temperature may correspond to a higher temperature than the second temperature. For example, the first temperature may correspond to approximately room temperature to 400°C, or the first temperature may correspond to approximately 400°C. Accordingly, in the first etching step, the substrate (S) may be heated to the first temperature by the upper heater (240) of the upper shower head (200).

[0136] For example, after the substrate (S) is placed on the substrate holder (410), both the substrate holder (410) and the lower shower head (420) can be raised to a process height as described in FIG. 4. In this case, the substrate (S) is placed on the substrate holder (410), and the substrate (S) can be spaced apart from the lower shower head (420). When the substrate holder (410) is raised in this way, the substrate (S) and the upper heater (240) are placed close together, so that the substrate (S) can be efficiently heated by the upper heater (240).

[0137] Furthermore, in the case of the first etching step, direct plasma can be used to etch a large amount of the second thin film (14).

[0138] For example, in the state of FIG. 4, RF power can be applied to the upper shower head (200) by the first RF power source (225). In this case, the second RF power source (485) does not apply RF power to the lower shower head (420). Additionally, the lower shower head (420) can be grounded.

[0139] In this case, the aforementioned second lower shower head plate (440) can function as a baffle or blocker plate.

[0140] By this, direct plasma is generated between the lower surface of the substrate (S) and the lower shower head (420), thereby etching the second thin film (14) on the lower surface of the substrate (S).

[0141] When the first etching step is completed, the thickness of the second thin film (14) may be very thin. For example, the thickness of the second thin film (14) may be 300 Å or less.

[0142] Meanwhile, the end point of the first etching step can be determined by analyzing the wavelength emitted from the thin film on the lower surface of the substrate (S) using an EPD (End Point Detector).

[0143] Figure 10 is a graph showing the wavelengths emitted from a thin film deposited on the lower surface of the substrate (S).

[0144] Referring to FIG. 10, the first wavelength (W1) can be observed while the second thin film (14) composed of nitride is being etched (T0~T1) as the first etching step proceeds.

[0145] If the second thin film (14) becomes thin while the first etching step is being performed, the first thin film (12) may be locally exposed. In this case, the observed wavelength may change. That is, a second wavelength (W2) caused by the first thin film (12) may be observed, and in this case, the first etching step may be terminated.

[0146] Next, a second etching step may be performed to etch the second thin film (14) of the substrate (S) at a second temperature.

[0147] That is, the second etching step is a step in which, rather than increasing the amount of etching of the second thin film (14) of the substrate (S), the selectivity is increased to etch only the second thin film (14), and the first thin film (12) is prevented from being etched. In the second etching step, one or more of CF4, SF6, CH2F2, NF3, NH3, O2, and F2 can be supplied toward the lower surface of the substrate (S), and N2, Ar, or He gas can be supplied through the upper shower head (200).

[0148] Meanwhile, when the film to be etched is an oxide film, one or more of CF4, SF6, CH2F2, NF3, NH3, O2, H2, and F2 may be supplied as etching gases; when the film to be etched is polysilicon, one or more of CF4, SF6, NF3, NH3, O2, H2, Cl2, BCl3, HBr, CCl4, C2ClF3, C2F4, CF3Cl, and C4F8 may be supplied as etching gases; when the film to be etched is a metal film (tungsten (W) or TiN), one or more of WF6, WCl6, WOCL4, Cl2, CF4, SF6, H2, NF3, and O2 may be supplied as etching gases; and when the film to be etched is a photoresist, one or more of HBr, Cl2, and BCl3 may be supplied as etching gases.

[0149] In addition, the etching gas supplied toward the lower surface of the substrate (S) in the first etching step and the second etching step may be the same as described above. However, the present invention is not limited thereto, and, for example, the type of etching gas supplied in the first etching step and the second etching step may vary depending on the type or properties of the film to be etched.

[0150] Meanwhile, in the second etching step, the second etching amount of the second thin film (14) of the substrate (S) may be smaller than the first etching amount of the second thin film (14) of the substrate (S) in the first etching step.

[0151] In addition, the second selectivity ratio of the second thin film (14) of the substrate (S) in the second etching step may be greater than the first selectivity ratio of the second thin film (14) of the substrate (S) in the first etching step.

[0152] For example, in the second etching step above, the etching rate may be approximately 20 Å / s or less, and the selectivity ratio may be approximately 100 or more.

[0153] Ultimately, the second etching step may correspond to a process of increasing the selectivity of etching the second thin film (14) rather than the amount of etching.

[0154] The above second etching step can be performed at a relatively low temperature. That is, the second temperature may be lower than the first temperature. For example, the second temperature may be approximately -10°C to 90°C. Or, the second temperature may be approximately 10°C to 40°C.

[0155] Accordingly, a step of lowering the temperature of the substrate (S) between the first etching step and the second etching step may be included.

[0156] In this way, the step of lowering the temperature of the substrate (S) can be performed in various ways.

[0157] For example, the first etching step and the second etching step described above can both be performed in the chamber (300) described in the present invention. That is, the first etching step and the second etching step can be performed in a single chamber (300).

[0158] In this case, the step of lowering the temperature of the substrate (S) can be performed through the step of FIG. 2 described above.

[0159] That is, when the substrate holder (410) is lowered, the edge of the substrate holder (410) can be seated on the stepped portion (431) of the first lower shower head plate (430).

[0160] When the edge of the substrate holder (410) is seated on the stepped portion (431), the lower surface of the substrate (S) can be seated on the upper surface of the first lower shower head plate (430). When the lower surface of the substrate (S) is seated on the upper surface of the first lower shower head plate (430), the temperature of the substrate (S) can be lowered to the second temperature by heat conduction from the first lower shower head plate (430), which has a relatively lower temperature.

[0161] In addition, in another embodiment, the first etching step and the second etching step may be performed in separate chambers (300). That is, a first chamber (not shown) set to the first temperature and a second chamber (not shown) set to the second temperature may be provided, and the first etching step may be performed in the first chamber, and the substrate (S) may be moved to the second chamber to perform the second etching step. Here, the first chamber and the second chamber may have a structure similar to the chamber (300) according to FIG. 1 described above.

[0162] As described above, when the substrate (S) in a single chamber (300) has its temperature lowered to a second temperature, the substrate holder (410) can then be raised (or the lower shower head (420) lowered) to separate the substrate (S) from the lower shower head (420).

[0163] Afterwards, as described in FIG. 4, both the substrate holder (410) and the lower shower head (420) can be raised to a process height. In this case, the substrate (S) is placed on the substrate holder (410), and the substrate (S) can be spaced apart from the lower shower head (420).

[0164] Furthermore, in the case of the second etching step, a remote plasma can be used to etch the second thin film (14).

[0165] That is, when RF power is applied to the second lower shower head plate (440) by the second RF power source (485), the process gas passing through the second lower shower head plate (440) can generate plasma in the plasma space (432) and be supplied toward the lower surface of the substrate (S) in the form of remote plasma through the first lower shower head plate (430).

[0166] At this time, the counter electrode of the second lower shower head plate (440) may be the first lower shower head plate (430).

[0167] And, the first lower shower head plate (430) can be grounded, and the first lower shower head plate (430) can function as an ion filter that filters ions from the plasma generated in the plasma space (432).

[0168] Through this structure, the lower part of the substrate (S) can be exposed to etching radicals by remote plasma.

[0169] In this case, the first RF power source (225) does not apply RF power to the upper shower head (200).

[0170] Meanwhile, the second etching step can be performed for a predetermined amount of time.

[0171] In the case of undergoing the two etching steps described above, the second thin film (14) can be etched from the bottom of the substrate (S) as shown in (C) of Fig. 9.

[0172] Although the present invention has been described above with reference to preferred embodiments, those skilled in the art may modify and change the present invention in various ways without departing from the spirit and scope of the invention as described in the claims below. Therefore, if a modified embodiment basically includes the components of the claims of the present invention, it should be considered to be included within the technical scope of the present invention. Explanation of the symbols

[0173] S: Substrate 110 : 2nd tilting housing 120 : 2nd tilting drive unit 200 : Top shower head 300: Chamber 310 : Processing space 400 : Substrate support 410 : Board holder 411 : Extension part 420 : Bottom shower head 430 : 1st lower shower head plate 440 : Second lower shower head plate 450 : Bottom plate 470 : Drive bar 500 : 2nd tilting unit 510 : Second tilting plate 540 : 2nd vertical connecting bar 600: 2nd Lifting / Lowering Unit 610 : 2nd lifting / lowering plate 620 : 1st tilting drive unit 630 : 1st tilting drive unit 630 : 1st tilting housing 700 : 1st tilting unit 710 : 1st tilting plate 740 : 1st vertical connecting bar 750: 1st Lifting / Lowering Unit 760 : 1st lifting / lowering plate 810 : 2nd lifting / lowering drive unit 820 : 1st lifting / lowering drive unit 1000 : Substrate processing device

Claims

Claim 1 A substrate processing apparatus comprising: a chamber providing a processing space for a substrate; an upper shower head providing purge gas toward the upper surface of the substrate and heating the substrate to a first temperature; a first RF power source providing RF power to the upper shower head; a substrate holder supporting the edge of the substrate; and a lower shower head providing process gas toward the lower surface of the substrate, heating the substrate to a second temperature, and configured to be movable relative to the substrate holder in a vertical direction; wherein the lower shower head is provided on the inner side of the substrate holder, and a step portion is formed on the edge of the lower shower head for the substrate holder to be seated thereon, so that the substrate holder is configured to be lowered below the upper surface of the lower shower head, and when the substrate holder and the lower shower head move relative to each other in a vertical direction, the lower surface of the substrate is seated on the upper surface of the lower shower head in a manner that allows for heat conduction. Claim 2 delete Claim 3 A substrate processing device according to claim 1, characterized in that the height of the stepped portion is formed to be greater than or equal to the thickness of the substrate holder. Claim 4 A substrate processing apparatus comprising: a chamber providing a processing space for a substrate; an upper shower head providing purge gas toward the upper surface of the substrate and heating the substrate to a first temperature; a first RF power source providing RF power to the upper shower head; a substrate holder supporting the edge of the substrate; and a lower shower head providing process gas toward the lower surface of the substrate, heating the substrate to a second temperature, and configured to be movable relative to the substrate holder in a vertical direction; wherein, when the substrate holder and the lower shower head move relative to each other in a vertical direction, the lower surface of the substrate is heat-conductively seated on the upper surface of the lower shower head, and the lower shower head comprises a first lower shower head plate that supplies process gas toward the lower surface of the substrate and a second lower shower head plate disposed below the first lower shower head plate. Claim 5 A substrate processing device according to claim 4, wherein the lower shower head further comprises a lower plate, a buffer space is formed between the lower plate and the second lower shower head plate, and a plasma space in which plasma is generated is formed between the second lower shower head plate and the first lower shower head plate. Claim 6 A substrate processing device according to claim 4, further comprising a second RF power source that provides RF power to the lower shower head, wherein the second RF power source is connected to the second lower shower head plate.

Images