JP2020072243A - Dry etching method and dry etching device - Google Patents

Abstract

To provide a dry etching method capable of preventing an object to be processed from being fixed to a clamp after performing a dry etching process.SOLUTION: There is provided a dry etching method according to the present invention for an object to be processed which is formed from a substrate having a resist mask P patterned on an outermost layer. An intermediate CS is arranged in place of the resist mask on a part or all of an outer edge portion on the outermost layer of the substrate, and the substrate is pressed from above an intermediate using a clamp CL, thereby fixing the substrate to a stage ST of a dry etching device. At that time, it is preferable to dispose the resist mask and the intermediate apart from each other, or to use the intermediate having a larger thickness than that of the resist mask. An elastic body or a dielectric body is suitable as the intermediate. A conductor is desirable as the clamp.SELECTED DRAWING: Figure 3F

Description

  The present invention relates to a dry etching method and a dry etching apparatus. More specifically, the present invention relates to a dry etching method and a dry etching apparatus that can prevent a clamp for fixing an object to be processed to a stage after the dry etching processing from being fixed to the object to be processed.

  In a dry etching apparatus, as a means for fixing a substrate made of a rigid body such as a Si wafer, glass, or ceramics, a configuration is known in which a peripheral portion of the substrate is pressed and fixed to a stage on which the substrate is mounted. For example, in such a clamp, the contact for pressing and fixing the wafer includes a plurality of contact portions that come into contact with the wafer by either point contact, line contact or surface contact, and the contact portions are the outer circumference of the wafer surface. A configuration of pressing the near edge portion is adopted (cited document 1). In the case of the reference document 1, the plurality of contact portions are arranged on an annular support, and the plurality of contact portions are configured to press the outer peripheral portion of the wafer. Therefore, plasma wraps around from the gap of the non-pressed portion, the non-covered portion of the outer periphery of the substrate and the side surface of the substrate are etched, and the resist film is peeled off, or the peeled off portion causes particles, which needs to be improved. It was

  With respect to the problem of the cited document 1, the clamp has an annular structure that covers the outer peripheral portion and side surfaces of the substrate over the entire circumference, and is made of an inorganic film that suppresses adhesion of resist material on the contact surface side of the clamp that contacts the substrate. A dry etching apparatus having an anti-adhesion layer has been proposed (Reference 2). According to this structure, since the non-pressing portion does not exist between the clamp and the substrate, it is possible to prevent the plasma from flowing around in the gap between the non-pressing portions. However, the anti-adhesion layer in the dry etching apparatus of the reference document 2 is fixedly arranged on the contact surface side of the clamp that comes into contact with the substrate, and the adhering ability of the anti-adhesion layer changes as the number of etching treatments increases. There was a risk that the initial adhesion ability would be unstable. Further, since the adhesion preventing layer cannot be easily replaced, improvement is required also from the viewpoint of maintainability.

  In the inventions described in the cited document 1 and the cited document 2, a substrate made of a rigid body such as a Si wafer is an object to be etched (processed body). In recent years, in addition to a substrate made of such a rigid body, a substrate made of a flexible member typified by a resin, that is, a film provided on a so-called flexible substrate can be etched, and a dry etching method and a dry etching method. An etching device is required.

  5A and 5B are schematic cross-sectional views of the target object S showing a state in which the coating M and the resist P are provided in this order on the substrate B made of a flexible member and the resist P is patterned. is there. FIG. 5A shows an ideal case, in which the substrate B maintains a flat plate shape without distortion, the flatness of the coating M and the resist P laminated on the substrate B is maintained, and the object S1 (S) to be processed is also maintained. It is in a flat state. On the other hand, in reality, as shown in FIG. 5B, since the substrate B made of a flexible member is warped or bent, the film M or the resist P provided on the substrate B is also warped or warped. The flexure propagates and the flatness of the object S2 (S) is impaired.

  Both FIG. 5C and FIG. 5D show the case where the object S2 (S) shown in FIG. 5B is placed on the stage during the etching process. 5C shows a case where the stage ST is an electrostatic chuck stage (ESC: Electro chuck stage), and FIG. 5D shows a case where the stage ST is a mechanical chuck stage (MC). In FIG. 5D, CL is a clamp, which is means for contacting the surface of the resist P and pressing the object S2 (S) against the stage.

  As shown in FIGS. 5C and 5D, the back surface of the substrate is locally floated from the surface of the stage (the surface on which the substrate is placed) regardless of the type of the stage, and thus forms the processing surface of the processing target S2. The coating M and the resist P cannot maintain flatness. Therefore, the problem that the etching process for the processing surface of the processing target S2 becomes non-uniform within the processing surface is likely to occur.

As one of methods for solving the above-mentioned problem, a method using the glass carrier G and the electrostatic chuck stage ESC (FIGS. 6A to 6C) is being studied. In FIGS. 6A to 6C, a portion corresponding to the processing target S1 (S) in FIG. 5A is reference numeral S51 (S).
FIG. 6A is a cross-sectional view showing the structure PBX1 in which the target object S51 is placed on the glass carrier G. The processing object S51 is fixed to the glass carrier G by, for example, an adhesive portion BT (Bonding Tape). In the glass carrier G, for example, a metal film RM is arranged on the side in contact with the electrostatic chuck stage ESC to form the structure PBX1.
6B and 6C respectively show the structure PBX2 before and the structure PBX3 after being mounted on the electrostatic chuck ESC. As described above, by using the glass carrier G and the electrostatic chuck ESC, the problem of FIG. 5B (the problem of impairing the flatness of the object to be processed S2 (S)) is solved.

On the other hand, in the method using the glass carrier G and the mechanical chuck stage MC (FIGS. 7A to 7E), the problem of FIG. 5B is solved, but another problem occurs.
The mechanical chuck stage MC is different from the electrostatic chuck stage ESC described above in that the structure PBY3 is pressed against the mechanical chuck stage MC (ST) using the clamp CL (FIG. 7C). The downward arrow in FIG. 7C represents the pressing direction. The clamp CL when it is pressed comes into contact with the resist P, and in this state, the etching process is performed on the structure PBY4 (FIG. 7D). After the etching process, when the clamp CL is lifted to separate from the structure PBY5, the resist P of the structure PBY5 adheres to the clamp CL and the structure PBY5 sticks to the clamp CL (FIG. 7E). There was a possibility that the problem.

  If the structure body PBY5 sticks to the clamp CL, the next step (for example, a film forming process) cannot be performed on the structure body PBY5. Therefore, in the method using the glass carrier G and the mechanical chuck stage MC, it has been expected to develop a method capable of solving the problem that the structural body PBY5 sticks to the clamp CL.

JP, 2002-299422, A JP, 2014-154866, A

  The present invention has been made in view of the above circumstances, in which the structure whose outermost surface is made of a resist is placed on the mechanical chuck stage, and the structure is etched with the clamp being pressed against the mechanical chuck stage. It is an object of the present invention to provide a dry etching method and a dry etching apparatus that can prevent the structure PBY5 from adhering to the clamp later.

The dry etching method according to claim 1 of the present invention is a dry etching method for an object to be processed which comprises a substrate having a resist mask patterned on the outermost layer,
An intermediate body (cushion material) is arranged in place of the resist mask on a part or all of the outer edge portion (region) of the outermost layer of the substrate, and the substrate is pressed from above the intermediate body by using a clamp. The substrate is fixed to the stage of the dry etching apparatus by means of.
A dry etching method according to a second aspect of the present invention is the dry etching method according to the first aspect, characterized in that the resist mask and the intermediate are separated from each other.
A dry etching method according to a third aspect of the present invention is characterized in that, in the first or second aspect, the intermediate body having a larger thickness than the resist mask is used.
The dry etching method according to claim 4 of the present invention is the dry etching method according to any one of claims 1 to 3, wherein the intermediate body is made of a resin material having an elastic modulus [GPa] within a range of 2 to 4. It is characterized by using the body.
The dry etching method according to claim 5 of the present invention is the dry etching method according to any one of claims 1 to 3, wherein a resin material having a dielectric constant [F / m] of 2 to 4 is used as the intermediate. Is used.
The dry etching method according to claim 6 of the present invention is the dry etching method according to any one of claims 1 to 3, wherein the clamp is made of a conductive ceramic material having a dielectric constant [F / m] in the range of 7 to 10. It is characterized by being used.

A dry etching apparatus according to claim 7 of the present invention is a dry etching apparatus for an object to be processed which comprises a substrate having a resist mask patterned on an outermost layer, the chamber having a space for dry etching, A stage for placing the substrate placed in a chamber, a clamp for holding the substrate from above the resist mask and fixing the substrate to the stage, and introducing a process gas into the space in the chamber. A gas supply means for reducing the pressure in the chamber, and a gas exhaust means for reducing the pressure in the chamber.
At least
When an intermediate body (cushion material) is placed in place of the resist mask on a part or all of the outer edge portion of the outermost layer of the substrate, and the dry etching process is performed, the clamp is applied only to the intermediate body. It is characterized in that the substrate is brought into contact with the substrate from above and the substrate is fixed to the stage via the intermediate body.

  According to the dry etching method of the present invention, a part of the outer edge portion (area) of the outermost surface layer of the substrate is dry-etched when an object to be processed consisting of a substrate having a resist mask (patterned resist) on the outermost surface layer Alternatively, instead of the resist mask, an intermediate body (cushion material) is arranged in all of them. The clamp does not contact the resist mask but only the intermediate body (cushion material), and the substrate is pressed against the mechanical chuck stage using the clamp for etching. By using a member that does not easily adhere to the clamp as the intermediate body (cushion material), it is possible to obtain a dry etching method that can prevent the adhesion between the substrate and the clamp after the etching process.

The dry etching apparatus of the present invention performs the above-described dry etching method,
(When performing a dry etching process), only the intermediate body (cushion material), which is placed on a part or the whole of the outer edge portion of the outermost layer of the substrate to be processed, is replaced with the intermediate body (cushion material) Then, the substrate is pressed from above, and the substrate is fixed to the stage via the intermediate body. This makes it possible to avoid contact between the resist mask and the stage. INDUSTRIAL APPLICABILITY The present invention contributes to the provision of a dry etching apparatus capable of preventing the clamp from adhering to the substrate after the etching process.

1 is a schematic configuration diagram showing an example of a dry etching apparatus according to the present invention. FIG. 2 is a schematic configuration diagram showing a main part of the dry etching apparatus of FIG. 1. The schematic block diagram which expands and shows the area | region (alpha) of FIG. 2A. The schematic cross section which shows the dry etching method which concerns on this invention. The schematic cross section which shows the next process of FIG. 3A. The schematic cross section which shows the next process of FIG. 3B. The schematic cross section which shows the next process of FIG. 3C. The schematic cross section which shows the next process of FIG. 3D. The schematic cross section which shows the next process of FIG. 3E. The schematic cross section which shows the next process of FIG. 3F. The schematic cross section which shows the example to which the dry etching method which concerns on this invention was applied. The schematic cross section which shows the next process of FIG. 4A. The schematic cross section which shows the next process of FIG. 4B. The schematic cross section which shows the next process of FIG. 4C. The schematic cross section which shows the next process of FIG. 4D. The schematic cross section which shows the next process of FIG. 4E. The schematic cross section which shows the next process of FIG. 4F. The schematic cross section which shows the next process of FIG. 4G. The schematic cross section which shows the next process of FIG. 4H. The schematic cross section which shows the next process of FIG. 4I. The schematic cross section which shows the case (ideal) of processing the coating film on a flexible substrate. The schematic cross section which shows the case (actual) which processes the coating film on a flexible substrate. 5B is a schematic cross-sectional view showing a state where the structure of FIG. 5B is placed on the electrostatic chuck stage. FIG. 6 is a schematic cross-sectional view showing a state in which the structure shown in FIG. 5B is placed on a mechanical chuck stage. The schematic cross section which shows the method of using a glass carrier and an electrostatic chuck stage. The schematic cross section which shows the next process of FIG. 6A. The schematic cross section which shows the next process of FIG. 6B. The schematic cross section which shows the method of using a glass carrier and a mechanical chuck stage. The schematic cross section which shows the next process of FIG. 7A. The schematic cross section which shows the next process of FIG. 7B. The schematic cross section which shows the next process of FIG. 7C. The schematic cross section which shows the next process of FIG. 7D.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an example of a dry etching apparatus used in the embodiment of the present invention. The illustrated dry etching apparatus 11 is configured as an NLD (magnetic Neutral Loop Discharge) type plasma etching apparatus. The configuration will be described below.

  The dry etching apparatus 11 includes a vacuum chamber 21, and a plasma forming space 21a is formed inside the vacuum chamber 21. An evacuation unit P such as a turbo molecular pump is connected to the vacuum chamber 21 and functions so that the inside of the vacuum chamber 21 is in a predetermined reduced pressure atmosphere.

  The circumference of the plasma forming space 21 a is partitioned by a cylindrical wall 22 that forms a part of the vacuum chamber 21. The cylindrical wall 22 is made of a transparent insulating material such as quartz. On the outer peripheral side of the cylindrical wall 22, a high-frequency coil (antenna) 23 for plasma generation connected to the first high-frequency power supply RF1, and three magnetic coils 24A, 24B arranged on the outer peripheral side of the high-frequency coil 23, The magnetic coil groups 24 each composed of 24C are arranged.

Currents are supplied to the magnetic coils 24A and 24C in the same direction, and currents are supplied to the magnetic coil 24B in the opposite direction to the other magnetic coils 24A and 24C. As a result, in the plasma formation space 21a, magnetic neutral wires 25 having a magnetic field of zero are continuously formed in an annular shape. Then, an induction electric field (high frequency electric field) is formed along the magnetic neutral wire 25 by the high frequency coil 23, so that discharge plasma is generated.
Particularly, in the NLD type plasma processing apparatus, the formation position and the size of the magnetic neutral wire 25 can be adjusted by the size of the current passed through the magnetic coils 24A to 24C.

  A top plate 28 is installed above the plasma forming space 21a. The top plate 28 is configured as a counter electrode of the stage 26, and is connected to the third high frequency power supply RF3 via a capacitor 29. Further, near the top plate 28, a gas introducing member 30 for introducing a process gas (etching gas) into the vacuum chamber 21 is installed.

  On the other hand, a stage 26 that supports the substrate S to be processed is installed inside the vacuum chamber. In this embodiment, a silicon substrate is used as the substrate S. The stage 26 is made of a conductor, and is connected to the second high-frequency power source RF2 via the capacitor 27. The second high frequency power supply RF2 is composed of a variable power supply capable of adjusting the voltage in multiple stages.

2A is a schematic configuration diagram showing a main part in the dry etching apparatus of FIG. 1, and FIG. 2B is a schematic configuration diagram showing an enlarged region α of FIG. 2A.
As shown in FIG. 2A, a mechanical clamp 36 that presses the peripheral edge of the substrate W against the upper surface of the stage 26 is installed above the stage 26. The stage 26 may include a heating source such as a heater for heating the substrate W to a predetermined temperature.

  As shown in FIG. 2B, in the outermost layer of the substrate S [shown as PBZ5 (PB) in FIG. 2B], a part or all of the outer edge portion (region) is replaced by the intermediate portion instead of the resist mask (resist) P. The body (cushion material) CS is arranged, and the substrate is fixed to the stage ST of the dry etching apparatus by pressing the substrate from above the intermediate body CS using the clamp CL. That is, in the dry etching apparatus of the present invention, the clamp CL contacts only the intermediate C and does not contact the resist P. This solves the problem that the clamp CL adheres to the resist P after the etching process.

  In the dry etching apparatus of the present invention, since the intermediate C is arranged on the side of the substrate PBZ5 (PB) to be etched, the clamp CL comes into contact with a new intermediate C each time the substrate to be processed is replaced. It will be. In the present invention, the intermediate body C is not arranged on the clamp CL side. As a result, problems such as a problem when the intermediate body C is arranged on the clamp CL side, a surface of the intermediate body C is reduced with an increase in the number of substrates to be processed, and a contact state with the substrate becomes unstable, etc. Can be avoided.

In the present invention, since the intermediate C exists on the side of the substrate to be processed, it is possible to flexibly change various conditions of the intermediate CS according to the etching processing conditions, the material of the clamp CL, and the like.
Examples of the material of the intermediate CS include polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polycarbonate (PC), polystyrene (PS), acrylic (Acryl), polyimide (Polyimide), and the like. Among them, polyimide is excellent as a material that can be expected to retain mechanical properties in the expected substrate temperature range of plasma etching (about -20 ° C to 150 ° C) because of its high heat resistance (glass transition point> 300 ° C). It is suitable.

  As the intermediate CS, for example, an elastic body made of a resin material having a modulus of elasticity [GPa] within the range of 2 to 4 is preferable. When the elastic modulus is lower than 2 [GPa], there is a large difference from the elastic modulus of polyimide, which is the assumed material of the substrate B, the strain of the cushion material itself becomes large, and the fixation of the substrate becomes unstable, which is not good. When the elastic modulus is higher than 4 [GPa], the strain of the substrate B itself becomes large and the fixing of the substrate becomes unstable, which is not good.

  As the intermediate CS, for example, a dielectric made of a resin material having a dielectric constant [F / m] in the range of 2 to 4 is preferable. When the dielectric constant is lower than 2 [F / m], it is low, but it is not good because it causes abnormal discharge at the contact portion between the intermediate CS and the substrate B. When the dielectric constant is higher than 4 [F / m], when the substrate bias high frequency (RF2 in FIG. 1) is applied, the bias high frequency acts relatively more strongly on the intermediate CS than on the substrate B, and the vicinity of the cushion material. It is not good because it causes the occurrence of abnormalities such as burning of the substrate.

  Further, as the intermediate CS, for example, a resin material having a glass transition point of 200 ° C. or higher is preferable. When the glass transition temperature is lower than 200 ° C., if the temperature of the cushioning material during plasma etching exceeds 200 ° C., the mechanical properties of the cushioning material cannot be expected to be retained, and the fixation of the substrate becomes unstable, which is not good. If the glass transition point is higher than 200 ° C, no particular attention is required.

  The height (thickness) of the intermediate CS is preferably larger than the height (thickness) of the resist P. As a result, it is possible to reliably avoid the state in which the clamp CL contacts the resist P. The height (thickness) of the intermediate CS is preferably 0.5 to 1 mm, for example. If the height is lower than 0.5 mm, when the intermediate body CS is installed on the substrate B (for example, held by an operator), it may be easily distorted by an external force, which is not good. When the height is higher than 1 mm, the plasma sheath strain at the edge of the substrate due to the intermediate CS becomes larger, so that the ion trajectories incident on the substrate at the edge of the substrate are deflected, which affects the plasma etching distribution in the entire substrate. Is not good.

  As the clamp, for example, a dielectric ceramic having a dielectric constant [F / m] within the range of 7 to 10 is preferable. When the dielectric constant is lower than 7 [F / m], the clamp material surface may contain a large amount of pores, and the plasma facing surface of the clamp may be quickly consumed by plasma etching, which is not good. When the dielectric constant is higher than 10 [F / m], the substrate bias high frequency (RF2 in FIG. 1) is easily transmitted to the clamp side, which causes the loss of the substrate bias action, and the plasma etching characteristic is reduced. It is unstable and not good. However, if mechanical transmission of high frequencies to the clamp ring can be mechanically suppressed, dielectric ceramics having a dielectric constant higher than 10 [F / m] may be used.

Hereinafter, the dry etching method according to the present invention will be described with reference to FIGS. 3A to 3G together with the operation of the dry etching apparatus described above. The dry etching method according to the present invention is a method using the glass carrier G and the mechanical chuck stage ST (MC).
FIG. 3A shows a schematic cross-sectional view of the structure PBZ1 (PB) including the object S52 (S) to be dry-etched. The object S52 (S) has a resist mask (patterned resist) P on the outermost layer.

  In FIG. 3A, a portion corresponding to the object S1 (S) of FIG. 5A is reference numeral S52 (S). The structural body PBZ1 (PB) is one in which the target object S52 is placed on the glass carrier G. The processing object S52 is fixed to the glass carrier G by, for example, an adhesive portion BT (Bonding Tape). Since the mechanical chuck stage ST (MC) is used in the present invention, the metal film RM is not required on the side where the glass carrier G is in contact with the mechanical chuck stage (see FIGS. 3D to 3G in the subsequent stage).

  Further, in the structure PBZ1 (PB), even if the object S52 to be processed is provided with the film M and the resist P in this order on the substrate B made of a flexible member and the resist P is patterned, Since the processing body S52 is mounted on the glass carrier G, the problem shown in FIG. 5B can be avoided.

  FIG. 3B is a schematic sectional view showing a step subsequent to FIG. 3A. In this step, a resist mask (patterning) is formed on part or all of the outer edge portion (region) of the outermost surface layer of the substrate B forming the structure PBZ2 (PB), that is, the outermost surface layer of the object to be processed S52 (S). Instead of the formed resist P, an intermediate body is arranged.

  When a sheet body is used as the intermediate body, for example, a flexible substrate made of polyimide (Polyimide) having an adhesive portion on one surface (lower surface) is used as an outer edge portion of the outermost layer of the processing object S52 (S). The sheet body is formed into a desired shape so as to cover a part or the whole of the (area), and then the sheet body is attached to the outermost surface layer of the object S52 (S).

  FIG. 3C is a schematic cross-sectional view showing the next step of FIG. 3B and shows a part or all of the outer edge portion (region) of the outermost surface layer of the object S52 (S) constituting the structure PBZ3 (PB). The state where the sheet body (intermediate body CS) is attached so as to cover is shown. In FIG. 3C, the resist P and the intermediate CS are drawn at the same level of height (thickness), but in reality, the height of the intermediate CS is larger than that of the resist P (thickness). Is set to.

  3D is a schematic cross-sectional view showing the next step of FIG. 3C, in which the mechanical chuck stage ST is arranged below the structure PBZ4 (PB) and the clamp CL is arranged above the structure PBZ4 (PB). Is represented. The lower surface of the tip portion of the clamp CL is arranged so as to cover a part or all of the outer edge portion (area) of the outermost surface layer of the object to be processed S52 (S) that constitutes the structural body PBZ4 (PB) when it descends. It is in a position where it abuts on the formed intermediate body CS.

  FIG. 3E is a schematic cross-sectional view showing the next step of FIG. 3D, and shows a state in which the structure PBZ5 (PB) is pressed and fixed onto the mechanical chuck stage ST using the clamp CL. At that time, the clamp CL is applied only to the intermediate body CS arranged so as to cover a part or all of the outer edge portion (area) of the outermost surface layer of the object to be processed S52 (S) forming the structure PBZ5 (PB). The lower surface of the tip end of the clamp CL contacts the resist CL, and the clamp CL does not contact the resist P. The area α in FIGS. 2A and 2B corresponds to the area α shown in FIG. 3E described above.

  FIG. 3F is a schematic cross-sectional view showing the next step of FIG. 3E, showing how the structure PBZ6 (PB) is dry-etched to form a recess in the coating M based on the pattern of the resist P. There is. In FIG. 3F, the dotted arrow indicates the direction of plasma propagation by dry etching, and the outermost surface layer of the object to be processed S52 (S) forming the structure PBZ6 (PB) is exposed to this plasma, so that the etching treatment is performed. Is done. At this time, since the intermediate CS is located between the lower surface of the tip of the clamp CL and the coating M, the upper surface of the intermediate CS is shielded from the plasma by the tip of the clamp CL.

FIG. 3G is a schematic cross-sectional view showing the next step of FIG. 3F, and shows how the clamp CL rises and moves away from the structure PBZ7 (PB) which has been subjected to the etching process. In FIG. 3G, the upward arrow shown beside the clamp CL is the moving direction (upward direction) of the clamp CL. Since the lower surface of the tip portion of the clamp CL is in contact with only the intermediate CS, the conventional problem [problem that the resist P (structure PB) sticks to the clamp CL] is solved.
Therefore, according to the present invention, it is possible to obtain the dry etching method and the dry etching apparatus capable of preventing the structure PB from adhering to the clamp after the etching process.

Hereinafter, an example in which the dry etching method described above is applied will be described with reference to FIGS. 4A to 4J. In this example, for example, Nb wiring is formed on a polyimide sheet.
(1) A glass carrier G (FIG. 4A) and a substrate B (FIG. 4B) made of a flexible member having an adhesive portion BT (Bonding Tape) on the lower surface are prepared. As the substrate B, for example, a polyimide sheet is preferably used, but the substrate B is not limited to this.

(2) The substrate B is superposed on the glass carrier G so that the adhesive portion BT is in contact with the upper surface of the glass carrier G (FIG. 4C).

(3) A cleaning process (CL) is performed on the upper surface of the substrate B (FIG. 4D). As the cleaning process, for example, a pre-etching process using an ion gun or an annealing process is used.

(4) The coating film M is formed on the upper surface of the substrate B that has been subjected to the cleaning treatment (FIG. 4E). A vapor deposition method or a sputtering method is preferably used for forming the coating film M. In this example, an Nb film is used as the film M.

(5) A resist P is applied to the film M, and a predetermined patterning process is performed by a lithography method. Further, the sheet body (intermediate body CS) is attached by the method described with reference to FIG. 3C so as to cover a part or the whole of the outer edge portion (area) of the surface of the coating film M (FIG. 4F). As a result, the structure PBZ4 (PB) is obtained in which the intermediate CS is attached so as to cover a part or all of the outer edge portion (region) of the outermost layer of the processing target S51 (S).

(6) The structure PBZ7 (PB) having the coating M subjected to desired patterning is obtained by dry etching the coating M by the method described with reference to FIG. 3F (FIG. 4G). ).

(7) The intermediate CS and the resist P are removed from the surface of the film M (FIG. 4H). As a result, the structure PBZ8 (PB) is obtained. Wet etching or dry etching is used for this removal. This removal may be performed separately for the intermediate CS and the resist P, or for the intermediate CS and the resist P at the same time. The latter is preferable because it can reduce the number of steps.

(8) The glass carrier G is removed from the structure PBZ8 (PB) (FIG. 4I). As a result, the structure PBZ9 (PB) is obtained. For this debonding, for example, ultraviolet irradiation (UV) peeling or thermal peeling method is used.

(9) The adhesive portion BT is removed from the back surface of the substrate B (FIG. 4J). As a result, the structure PBZ10 (PB) is obtained. This structural body PBZ10 (PB) becomes a target laminated body S51X (SX) in which the Nb wiring M is formed on the polyimide sheet B.

Through the steps (1) to (9) described above, it has been described in detail that the dry etching method according to the present invention is effective for the purpose of forming Nb wiring on the polyimide sheet.
Although the embodiment of the present invention has been described above, of course, the present invention is not limited to this, and various modifications can be made based on the technical idea of the present invention.

In the above embodiment, an example in which the flexible substrate is a polyimide sheet has been described, but the dry etching method of the present invention is not limited to the polyimide sheet, and another flexible substrate may be used. Other flexible substrates include, for example, polyethylene terephthalate (PET), polycarbonate (PC), polystyrene (PS), acrylic (Acryl), and the like.
Further, although the example in which the film M is the Nb film has been described, the dry etching method of the present invention is not limited to the Nb film, and another film may be used. Other coatings include, for example, Mg, Al, Ti, Cr, Mo, Ru, In, Ta, W, Pt, Au and the like.

  The present invention can be widely applied to a dry etching method and a dry etching apparatus. Such a dry etching method and a dry etching apparatus are particularly suitably used when forming a laminated body in which metal wiring is formed on a flexible substrate.

  α region, B substrate, BT adhesive portion, CL clamp, CS intermediate (sheet body, cushion material), G glass carrier, M film, P resist mask (patterned resist), PB (PBZ1, PBZ2, PBZ3, PBZ4) , PBZ5, PBZ6, PBZ7) structure, RM metal film, S (S1, S52) object to be processed, ST (MC) mechanical chuck stage.

Claims (7)

A dry etching method for an object to be processed, which comprises a substrate having a resist mask patterned on the outermost layer,
Of the outermost layer of the substrate, an intermediate is placed in place of the resist mask on a part or all of the outer edge portion,
A dry etching method, wherein the substrate is fixed to a stage of a dry etching apparatus by pressing the substrate from above the intermediate body using a clamp.   The dry etching method according to claim 1, wherein the resist mask and the intermediate body are arranged apart from each other.   The dry etching method according to claim 1 or 2, wherein the intermediate body having a larger thickness than that of the resist mask is used.   The dry etching method according to claim 1, wherein an elastic body made of a resin material having an elastic modulus [GPa] within a range of 2 to 4 is used as the intermediate body.   4. The dry etching according to claim 1, wherein a dielectric made of a resin material having a dielectric constant [F / m] within a range of 2 to 4 is used as the intermediate. Method.   The dry etching method according to any one of claims 1 to 3, wherein a conductive ceramics having a dielectric constant [F / m] within a range of 7 to 10 is used as the clamp. A dry etching apparatus for an object to be processed which comprises a substrate having a resist mask patterned on the outermost layer,
A chamber with a space for dry etching,
A stage for placing the substrate placed in the chamber, and a clamp for pressing the substrate from above the resist mask and fixing the substrate to the stage.
Gas supply means for introducing a process gas into the space in the chamber,
Gas exhaust means for reducing the pressure of the space in the chamber,
At least
Of the outermost layer of the substrate, an intermediate is placed in place of the resist mask on a part or all of the outer edge portion,
When performing the dry etching process, the clamp contacts only the intermediate body to press the substrate from above, and the substrate is fixed to the stage via the intermediate body.
A dry etching apparatus characterized in that

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