Resist removal method and resist removal device

Abstract

The invention provides a resist removal method and a resist removal apparatus. A heating plate (4) of the resist removal apparatus (1) is arranged in a processing space (20) and is heated to a predetermined temperature. A plurality of lift pins (51) hold a substrate (9) in a processing space (20), the substrate (9) having a pattern of a resist on the upper surface (91) thereof, the resist having a modified layer formed on the surface thereof. The pin lifting mechanism (32) moves the plurality of lifting pins (51) relative to the heating plate. The ozone gas supply unit (6) supplies ozone gas to the upper surface (91) of the substrate. The control unit (10) arranges the substrate at a first processing position at which a gap is formed between the substrate and the heating plate and removes the modified layer (96) by means of ozone gas, and then, by controlling the movement mechanism, arranges the substrate at a second processing position at which the gap is smaller than that of the first processing position and removes the resist by means of ozone gas. As a result, it is possible to efficiently remove the resist on the substrate while preventing bursting.

Description

[0001] This application is a divisional application of an application with an application date of June 15, 2018, application number 201880059923.0, and invention name “Resist Removal Method and Resist Removal Device”. Technical Field

[0002] The present invention relates to a resist removal method and a resist removal device. Background Art

[0003] In the past, in the manufacturing process of a semiconductor substrate (hereinafter referred to as a "substrate"), ion implantation was performed to implant ions into a material on the surface of the substrate to change the properties of the material. In the ion implantation, in order to prevent the ions from being implanted into unnecessary parts, a pattern of a photoresist (hereinafter referred to as a "resist") as a photosensitive material was formed on the surface of the substrate as a mask. After the ion implantation, the resist pattern was removed by a resist stripping solution and a resist removal process.

[0004] In recent years, the dose of ions in ion implantation has become higher. 15 ions / cm 2 In the case of ion implantation of the resist (above), a deteriorated layer (hardened layer) will be formed on the surface of the resist, which requires time to be removed by a resist stripping solution. Therefore, the following method is proposed in Japanese Patent Publication No. 2006-286830: the bond between carbon and hydrogen in the resist is cut by irradiating the surface of the substrate with ultraviolet rays, and then the resist stripping solution is supplied to the surface of the substrate to quickly remove the resist.

[0005] In addition, Japanese Patent Publication No. 1-186619 (Document 2) discloses a device for removing the resist on a substrate by ozone under heating. In the device, a support table is provided in a sealed reaction chamber, and the substrate is placed on the support table. In addition, a CO2 concentration measuring device is provided between the reaction chamber and the ozone decomposer on the downstream side. During the removal of the resist, the support table is heated and ozone is caused to flow in the reaction chamber. In addition, the CO2 concentration is measured by the CO2 concentration measuring device, and when the CO2 concentration is lower than a predetermined value, it is determined that the resist is completely decomposed and removed.

[0006] However, as described in Document 2, when a substrate that has been subjected to high-dose ion implantation is subjected to resist removal by supplying ozone gas and heating the substrate, a phenomenon in which the degenerate layer is formed in the resist may occur due to expansion of the inside (the part inside the degenerate layer). This phenomenon is called popping, and by popping, the pattern on the substrate collapses, or the scattered fragments of the degenerate layer adhere to the surface of the substrate and the inside of the device. Although it is also possible to prevent popping by lowering the heating temperature of the substrate, the time required to remove the resist will be longer. Summary of the invention

[0007] The present invention relates to a resist removal method for removing the resist of a substrate having a resist pattern with a deteriorated layer formed on the main surface. The purpose of the present invention is to efficiently remove the resist on the substrate while preventing cracking.

[0008] The resist removal method of the present invention is used to remove the resist of a substrate having a resist pattern on a main surface, wherein the resist has a deteriorated layer formed on the surface, wherein the resist removal method comprises: a) a process of arranging the substrate at a first processing position separated by a gap from a heating plate heated to a specified temperature in a processing space blocked from the outside, while supplying ozone gas to the main surface, thereby removing the deteriorated layer; and b) a process of arranging the substrate at a second processing position having a smaller gap than that of the first processing position, while supplying ozone gas to the main surface, thereby removing the resist after the a) process.

[0009] According to the present invention, the resist on the substrate can be removed efficiently while preventing blowout.

[0010] In a preferred embodiment of the present invention, the resist removal method further comprises: step c) performed in parallel with step a) to detect the end point of removal of the altered layer by measuring the concentration of a predetermined component in the gas exhausted from the processing space.

[0011] In this case, preferably, in the step c), an end point of removal of the altered layer is detected based on a rate of change in the concentration of the predetermined component.

[0012] In addition, the resist removal method may further include a step of detecting an end point of the resist removal by measuring the concentration of the predetermined component in the gas exhausted from the processing space, which step is performed in parallel with the step b).

[0013] In another preferred embodiment of the present invention, the processing space can be opened and closed. When the processing space is opened, the substrate is delivered from the holding portion that holds the substrate to an external conveying mechanism in a state where the substrate is configured at a position farther away from the heating plate than the first processing position.

[0014] In still another preferred embodiment of the present invention, a heating portion is provided around the ozone gas supply port in a processing space forming portion that forms the processing space.

[0015] In one embodiment of the present invention, the predetermined temperature of the hot plate is equal to or higher than a temperature at which the altered layer is cracked due to internal expansion in the resist having the altered layer formed thereon.

[0016] The present invention also provides a resist removal device. The resist removal device of the present invention comprises: a processing space forming part, which forms a processing space blocked from the outside; a heating plate, which is arranged in the processing space and is heated to a predetermined temperature; a holding part, which holds a substrate having a resist pattern on a main surface in the processing space, wherein the resist has a degenerate layer formed on the surface; a moving mechanism, which moves the holding part relative to the heating plate; an ozone gas supply part, which supplies ozone gas to the main surface; and a control part, which arranges the substrate at a first processing position separated from the heating plate by a gap and removes the degenerate layer using the ozone gas, and then, by controlling the moving mechanism, arranges the substrate at a second processing position having a smaller gap than the first processing position and removes the resist using the ozone gas.

[0017] The above-mentioned objects and other objects, features, embodiments and advantages will become more apparent from the following detailed description of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram showing the structure of a resist removal apparatus.

[0019] Figure 2 This is a diagram showing the resist removal apparatus in a state where the processing space is opened.

[0020] Figure 3 It is a cross-sectional view showing a resist.

[0021] Figure 4 It is a diagram showing the flow of the resist removal process.

[0022] Figure 5 This is a diagram of the resist removal apparatus showing a state in which a substrate is arranged at a first processing position.

[0023] Figure 6 It is a graph showing the change in ozone concentration in exhaust gas.

[0024] Figure 7 It is a graph showing changes in the carbon dioxide concentration in the exhaust gas.

[0025] Figure 8 It is a diagram showing another example of the resist removal apparatus. DETAILED DESCRIPTION

[0026] Figure 1 1 is a schematic diagram showing the structure of a resist removal apparatus 1 according to an embodiment of the present invention. The resist removal apparatus 1 is an apparatus for removing the resist of a substrate having a resist pattern on a main surface. The resist removal apparatus 1 includes a chamber 2, a cover lifting mechanism 31, a heating plate 4, a plurality of lift pins 51, a pin lifting mechanism 32, an ozone gas supply unit 6, a gas exhaust unit 71, a concentration measurement unit 72, and a control unit 10. The control unit 10 is responsible for overall control of the resist removal apparatus 1.

[0027] The chamber 2 has a chamber body 21 and a chamber cover 22. The chamber body 21 has a disc-shaped bottom plate 211 and a cylindrical main body side 212. The bottom plate 211 expands in the horizontal direction, and the main body side 212 extends upward from the outer edge of the bottom plate 211. The chamber cover 22 has a disc-shaped top plate 221 and a cylindrical cover side 222. The top plate 221 expands in the horizontal direction, and the cover side 222 extends downward from the outer edge of the top plate 221. A shower plate 223 that expands in the horizontal direction is fixed to the lower surface of the top plate 221 via a plate support 224. The shower plate 223 is arranged between the top plate 221 and the heating plate 4. A plurality of through holes are formed in the shower plate 223. The lower end surface of the cover side 222 is opposite to the upper end surface of the main body side 212 along the entire circumference in the up-down direction. An annular recess is provided on the upper end surface of the body side portion 212, and an O-ring 23 is provided in the annular recess. The chamber body 21 and the chamber cover 22 (including the shower plate 223) are formed of, for example, stainless steel.

[0028] The cover lifting mechanism 31 lifts the chamber cover 22 in the vertical direction and selectively places the chamber cover 22 in the chamber. Figure 1 The lower position shown and Figure 2 upper position as shown. Figure 2 In the embodiment, the chamber cover 22 is separated upward from the chamber body 21, and a large gap is formed between the lower end surface of the cover side portion 222 and the upper end surface of the body side portion 212. Figure 1 In the embodiment, the lower end surface of the cover side portion 222 is substantially in contact with the upper end surface of the main body side portion 212, and the upper side of the chamber main body 21 is blocked by the chamber cover portion 22. Figure 1 In the state, the lower end surface of the cover side portion 222 and the upper end surface of the main body side portion 212 are sealed by the O-ring 23, and the processing space 20 blocked from the outside is formed inside the chamber 2. The chamber 2 is a processing space forming part that forms the processing space 20. In addition, the processing space 20 can be opened and closed, and the cover lifting mechanism 31 is an opening and closing mechanism for opening and closing the processing space 20. A motor or an actuator other than a motor can be used in the cover lifting mechanism 31. The opening and closing mechanism can also be a mechanism for moving the chamber body 21.

[0029] The heating plate 4 is arranged in the processing space 20. The heating plate 4 is in the shape of a thick disk, and the diameter of the heating plate 4 is larger than the diameter of the disk-shaped substrate 9. A heater 40 including an electric heating wire is provided in the heating plate 4. The heating plate 4 is heated to a predetermined set temperature by an electric current supplied from an external power supply to the heater 40. The set temperature is, for example, 200° C. or higher and is higher than the explosion temperature described later at which explosion occurs. Figure 1 The upper limit of the set temperature in the heating plate 4 is, for example, 300°C. The heating plate 4 is fixed to the chamber body 21 via a member not shown in the figure. The central axes of the circular plate-shaped bottom plate portion 211, the top plate portion 221 and the heating plate 4 are substantially the same. In the following description, the circumferential direction with the central axis as the center is simply referred to as the "circumferential direction".

[0030] On the heating plate 4, a plurality of through holes 41 are arranged at certain angle intervals along the circumferential direction. On the bottom plate portion 211, a through hole 213 is provided at a position overlapping with each through hole 41 in the up and down direction. A plurality of lifting pins 51 are respectively inserted into any combination of the through holes 41 and the through holes 213. Typically, the number of the lifting pins 51 is three, in which case the lifting pins 51 are arranged at intervals of 120 degrees along the circumferential direction. The number of the lifting pins 51 may also be four or more. The lower ends of the plurality of lifting pins 51 are fixed to the pin support plate 52. Below the bottom plate portion 211, each lifting pin 51 is surrounded by a bellows 53. The upper end of the bellows 53 is fixed to the lower surface of the bottom plate portion 211, and the lower end of the bellows 53 is fixed to the upper surface of the pin support plate 52. The bellows 53 and the pin support plate 52 can prevent gas or liquid from passing through the through hole 213 of the bottom plate portion 211 between the inside and the outside of the chamber 2 .

[0031] The pin lifting mechanism 32 has a stepping motor for lifting the pin support plate 52 in the vertical direction. As a result, the plurality of lifting pins 51 can move in the vertical direction. By driving the stepping motor, the pin support plate 52 and the plurality of lifting pins 51 can be arranged in the vertical direction, for example Figure 1 The position shown is Figure 2 Any position between the positions shown. Figure 1In the embodiment, the top ends (upper ends) of the plurality of lift pins 51 are arranged inside the through hole 41 of the heating plate 4. Figure 2 In the embodiment, the top ends of the plurality of lift pins 51 are arranged above the upper surface of the heating plate 4. The top ends of the plurality of lift pins 51 are hemispherical and are located at the same height in the vertical direction. The pin lift mechanism 32 may also utilize other types of motors or actuators other than motors.

[0032] In the resist removal device 1, when the top ends of the plurality of lift pins 51 are arranged inside the through hole 41, the substrate 9 is placed on the upper surface of the heating plate 4 and is maintained in a horizontal posture. In addition, when the top ends of the plurality of lift pins 51 are arranged higher than the upper surface of the heating plate 4, the substrate 9 is supported from below by the plurality of lift pins 51 and is maintained in a horizontal posture. In this way, in the resist removal device 1, the holding portion that holds the substrate 9 in the processing space 20 is switched by the heating plate 4 and the plurality of lift pins 51. The pin lifting mechanism 32 is a moving mechanism that moves the holding portion relative to the heating plate 4 when the holding portion is a plurality of lift pins 51. In addition, a plurality of protrusions may also be provided on the upper surface of the heating plate 4. In this case, when the top ends of the plurality of lift pins 51 are lower than the upper surfaces of the plurality of protrusions, the substrate 9 is supported from below by the plurality of protrusions.

[0033] Figure 1 The ozone gas supply unit 6 has an ozone gas supply source 61, a gas supply pipe 62, a gas supply valve 63 and a gas nozzle 64. The gas nozzle 64 is arranged at the center of the top plate 221, and has a gas supply port 641 opened to the processing space 20 above the heating plate 4. The gas nozzle 64 is connected to the ozone gas supply source 61 via the gas supply pipe 62. A gas supply valve 63 is provided on the gas supply pipe 62. By opening the gas supply valve 63, ozone (O3) gas is supplied from the gas nozzle 64 to the processing space 20.

[0034] As described above, a shower plate 223 is disposed between the top plate portion 221 and the heating plate 4. Ozone gas is uniformly supplied to the upper main surface 91 (hereinafter referred to as "upper surface 91") of the substrate 9 through a plurality of through holes of the shower plate 223. A plurality of gas nozzles 64 may also be dispersedly provided on the top plate portion 221. In this case, the shower plate 223 may also be omitted. In this embodiment, the ozone gas is a gas obtained by diluting ozone with a prescribed gas. Other types of oxidizing gases may also be mixed in the ozone gas.

[0035] The gas exhaust portion 71 has a gas exhaust port 711 and a gas exhaust pipe 712. The gas exhaust port 711 is provided at the center of the bottom plate portion 211 and is connected to one end of the gas exhaust pipe 712. The other end of the gas exhaust pipe 712 is connected to an ozone decomposition portion (not shown) such as a filter. The gas in the processing space 20 is discharged to the outside via the gas exhaust port 711 and the gas exhaust pipe 712. In the resist removal device 1, a plurality of gas exhaust ports 711 may also be provided, and the gas exhaust port 711 may also be provided at the outer edge of the bottom plate portion 211 or the side portion 212 of the main body. A concentration measuring portion 72 is connected to the gas exhaust pipe 712. The concentration measuring portion 72 measures the concentration of a specified component in the gas (hereinafter referred to as "exhaust gas") exhausted from the processing space 20. In the present embodiment, the concentration of ozone and the concentration of carbon dioxide (CO2) in the exhaust gas are measured by the concentration measuring portion 72.

[0036] Next, the resist formed on the substrate 9 will be described. Figure 3 1 is a schematic diagram abstractly showing a cross section of a resist 95 formed on an upper surface 91 of a substrate 9. The substrate 9 processed in the resist removal apparatus 1 is subjected to high-dose ion implantation in the previous stage of processing, and a modified layer 96 is formed on the surface of the resist 95. In other words, in the resist 95, the entirety of the unmodified portion 97, which is a portion further inside than the modified layer 96, is covered by the upper surface 91 of the substrate 9 and the modified layer 96. The modified layer 96 is also called a hardened layer.

[0037] Here, when the substrate 9 having the resist 95 formed with the altered layer 96 is heated, the altered layer 96 may burst due to internal expansion (for example, filling with gas generated from the unaltered portion 97). The burst does not occur when the heating temperature of the substrate 9 is low. The temperature of the substrate 9 at which the burst occurs with a high frequency (for example, 50% or more) can be specified as the burst temperature through experiments, etc. The following describes a process for efficiently removing the resist 95 formed with the altered layer 96 while preventing the burst.

[0038] Figure 4 FIG. 1 is a diagram showing the flow of a resist removal process in the resist removal apparatus 1. In the resist removal process, first, the chamber cover 22 is disposed at Figure 2 Next, the substrate 9 is placed between the chamber cover 22 and the chamber body 21 through the gap between the lower end surface of the cover side portion 222 and the upper end surface of the body side portion 212 by an external transport mechanism. In addition, the plurality of lift pins 51 are moved upward to the position indicated by the pin lift mechanism 32. Figure 2Then, the transport mechanism moves the substrate 9 slightly downward, so that the substrate 9 is delivered from the support portion of the transport mechanism to the plurality of lift pins 51, and the substrate 9 is supported from below by the plurality of lift pins 51 (step S11). Figure 2 The position of the substrate 9 shown is referred to as a “handover position.” Alternatively, the substrate 9 may be delivered from the support portion to the plurality of lift pins 51 by moving the tips of the plurality of lift pins 51 upward from the support portion.

[0039] When the support portion of the transport mechanism moves to the outside of the chamber body 21 and the chamber cover 22, the plurality of lift pins 51 descend, and the substrate 9 moves downward from the delivery position to the chamber cover 22. Figure 5 The chamber cover 22 is lowered by the cover lifting mechanism 31 and disposed at the position shown in FIG. 1 (hereinafter referred to as the "first processing position") (step S12). In the first processing position, a gap of a predetermined width (for example, several mm) is provided between the lower surface of the substrate 9 and the upper surface of the heating plate 4. Figure 5 Thus, the processing space 20 blocked from the outside is formed (step S13). In other words, the processing space 20 is closed.

[0040] The heating plate 4 is heated to a certain set temperature, and the substrate 9 is close to the heating plate 4 with a gap therebetween. Figure 5 In the state, the substrate 9 is heated to a temperature lower than the set temperature of the heating plate 4. In fact, the set temperature and the width of the gap are determined by experiments, etc. so that the temperature of the substrate 9 becomes lower than the bursting temperature.

[0041] Next, the gas supply valve 63 in the ozone gas supply unit 6 is opened, and ozone gas is ejected from the gas supply port 641 into the processing space 20 at a predetermined supply flow rate. That is, the supply of ozone gas to the upper surface 91 of the substrate 9 is started (step S14). The supply of ozone gas is continuously performed in parallel with the heating of the substrate 9 by the heating plate 4. Figure 1 The discharge valve (not shown) of the gas discharge pipe 712 shown is opened, and the discharge action of the gas in the processing space 20 is also started. Near the upper surface 91 of the substrate 9, the ozone gas is heated and decomposed to generate oxygen radicals, etc. Through the oxygen radicals, etc., the decomposition of the outermost surface of the resist 95 is gradually carried out. In the concentration measurement unit 72, the ozone concentration and the carbon dioxide concentration in the exhaust gas are always measured, and the measured values ​​are output to the control unit 10.

[0042] Figure 6 is a graph showing changes in ozone concentration (O3 concentration) in exhaust gas. Figure 7This is a graph showing changes in the carbon dioxide concentration (CO2 concentration) in the exhaust gas. Figure 6 and Figure 7 In FIG. 1 , solid lines L1 and L2 are used to represent the changes in the concentration of ozone and carbon dioxide in the exhaust gas. Figure 6 In FIG. 2 , the dotted line L3 indicates the change in ozone concentration obtained when the substrate 9 is not disposed in the processing space 20, and the dotted line L4 indicates the change in ozone concentration obtained when the resist 95 on the substrate 9 does not have the altered layer 96. Figure 6 and Figure 7 The lower end of the chamber also shows the open and closed state of the chamber cover 22 and the open and closed state of the ozone gas (gas supply valve 63). Figure 6 and Figure 7 In the process, the supply of ozone gas to the upper surface 91 of the substrate 9 starts at time T1.

[0043] The air in the processing space 20 is replaced little by little by the ozone gas. Figure 6 As shown by the solid line L1 in FIG. 1 , the ozone concentration in the exhaust gas gradually increases from the start of the supply of the ozone gas. At this time, a portion of the ozone gas is used to remove the resist 95 on the substrate 9, more precisely, to decompose the altered layer 96. Therefore, compared with the change in ozone concentration when no substrate 9 is arranged in the processing space 20 (dashed line L3), the ozone concentration at each moment becomes smaller. In addition, as shown in FIG. Figure 7 As shown by the solid line L2 in FIG. 1 , the carbon dioxide concentration gradually increases due to the decomposition of the metamorphic layer 96. In the early stage of resist removal, most of the resist 95 removed is the metamorphic layer 96. In the following description, such a period is referred to as the "metamorphic layer removal period". In addition, assuming that the resist 95 on the substrate 9 does not have the metamorphic layer 96 (in this case, the substrate 9 is arranged at Figure 1 As shown in the position, since more ozone gas is used to decompose the resist 95, the ozone concentration at each time (single-dot chain line L4) becomes smaller than the solid line L1.

[0044] When the degraded layer 96 is decomposed by supplying ozone gas, a portion of the undegraded portion 97 is exposed in the resist 95. Since the undegraded portion 97 is easier to decompose than the degraded layer 96, more ozone gas is consumed than during the removal of the degraded layer, and the rate of change of the ozone concentration becomes smaller. In the control unit 10, the rate of change of the ozone concentration is always calculated during the removal of the resist. When the rate of change of the ozone concentration becomes below a predetermined threshold value, it is determined that the removal of most of the degraded layer 96 has been completed (step S15). In this way, the end point of the removal of the degraded layer 96 can be detected based on the rate of change of the ozone concentration. Figure 6 and Figure 7In the embodiment of the present invention, at time T2, the removal of the altered layer 96 is substantially completed.

[0045] When the end point of removal of the altered layer 96 is detected, or when a predetermined time has passed since the detection of the end point, the plurality of lift pins 51 are lowered, and the substrate 9 is moved downward from the first processing position to the Figure 1 The substrate 9 is placed on the upper surface of the heating plate 4, and no gap is provided between the lower surface of the substrate 9 and the upper surface of the heating plate 4 (step S16). In other words, the width of the gap becomes 0. The temperature of the substrate 9 arranged at the second processing position becomes higher than when it is arranged at the first processing position. In fact, the temperature of the substrate 9 rises to near the set temperature of the heating plate 4. Therefore, the decomposition of the ozone gas near the upper surface 91 of the substrate 9 is more promoted than during the removal of the degraded layer when the substrate 9 is arranged at the first processing position. As a result, the decomposition of the remaining resist 95 (mainly the undegraded portion 97) can also be promoted. In the resist removal device 1, if the gap between the substrate 9 arranged at the second processing position and the heating plate 4 becomes smaller than the gap in the first processing position, the substrate 9 at the second processing position can also be away from the heating plate 4.

[0046] As the amount of resist 95 remaining on the substrate 9 decreases, the concentration of carbon dioxide in the exhaust gas decreases. After that, the ozone concentration will be saturated at a certain constant value, and the carbon dioxide concentration will be approximately 0. In the control unit 10, when the carbon dioxide concentration becomes below a predetermined threshold value, it is determined that the removal of the undegraded portion 97 has been completed (step S17). In this way, by measuring the carbon dioxide concentration, the end point of the removal of the resist 95 can be detected. In the resist removal device 1, after the removal of the degraded layer 96, by configuring the substrate 9 to the second processing position, the removal of the resist 95 can be completed in a short time compared to the case where the processing is continued while the substrate 9 is configured to the first processing position.

[0047] At time T3, when the end point of the removal of the resist 95 is detected, the gas supply valve 63 is closed at time T4 after a predetermined time from time T3, and the supply of ozone gas is stopped (step S18). Thus, the processing of the substrate 9 using ozone gas is terminated. The time from time T3 to time T4 is the time (overetching time) set to more reliably remove the resist 95 on the substrate 9. In fact, the discharge valve (not shown) provided in the gas discharge pipe 712 is closed, and the discharge action of the gas in the processing space 20 is also stopped. In addition, after the supply of ozone gas is stopped, nitrogen gas or the like may be supplied to the processing space 20, so that the ozone gas in the processing space 20 is replaced by nitrogen gas.

[0048] Next, the chamber cover 22 is raised by the cover lifting mechanism 31 and is disposed at Figure 2 As a result, the processing space 20 is opened (step S19). In addition, the substrate 9 is moved upward from the second processing position to the upper position by the plurality of lifting pins 51 rising. Figure 2 The substrate 9 is then delivered to the support portion from the plurality of lift pins 51 (step S21). In the resist removal device 1, the substrate 9 is moved upwards to the support portion 51. Figure 5 In the state where the substrate 9 is arranged at the first processing position further away from the heating plate 4, the substrate 9 is delivered to the transport mechanism from the plurality of lift pins 51 holding the substrate 9. Thereafter, the substrate 9 is carried out to the outside of the resist removal apparatus 1 through the gap between the lower end surface of the cover side portion 222 and the upper end surface of the main body side portion 212. Thus, the resist removal process for the substrate 9 is completed. When there is a substrate 9 to be processed next, the processes of step S11 to step S21 are repeated for the substrate 9.

[0049] Here, a comparative example of resist removal apparatus is described. In the comparative example of resist removal apparatus, after the substrate 9 is loaded, the substrate 9 is placed on Figure 1 The second processing position shown in FIG. 1 is used to remove the resist 95 (the altered layer 96 and the unaltered portion 97). As described above, in the resist 95 formed with the altered layer 96, the temperature at which the altered layer 96 breaks due to internal expansion is set as the bursting temperature, and the set temperature of the heating plate 4 is above the bursting temperature. Therefore, in the resist removal device of the comparative example, the resist 95 may sometimes burst. Figure 3 In FIG. 1 , the expansion of the unaltered portion 97 is indicated by arrow A1 .

[0050] When bursting occurs, the pattern on the substrate 9 collapses, or the fragments of the flying degenerate layer 96 adhere to the upper surface 91 of the substrate 9 and the inside of the chamber 2. It is also considered to prevent the bursting by setting the set temperature of the heating plate 4 to be lower than the bursting temperature. However, the removal rate of the resist 95 is affected by the temperature of the substrate 9, so the time required to remove the resist 95 will be longer. In addition, there is also the possibility of excessive oxidation of the substrate 9. In addition, although it is also considered to change the set temperature of the heating plate 4 during the removal of the resist, it is difficult to change the temperature sharply in the heating plate 4.

[0051] In contrast, in the resist removal apparatus 1, the substrate 9 is arranged at a first processing position with a gap relative to the heating plate 4, and the deteriorated layer 96 is removed using ozone gas. Next, by controlling the pin lifting mechanism 32, the substrate 9 is arranged at a second processing position with a gap smaller than that of the first processing position with the heating plate 4, and the resist 95 is removed using ozone gas. Thus, the heating plate 4, which is difficult to change the temperature rapidly, can be used to efficiently (in a short time) remove the resist 95 on the substrate 9 while preventing bursting. As a result, excessive oxidation of the substrate 9 can also be suppressed. In addition, by making the second processing position a position where the substrate 9 contacts the upper surface of the heating plate 4, the substrate 9 can be efficiently heated to a high temperature.

[0052] By measuring the concentration of a predetermined component in the gas exhausted from the processing space 20 in parallel with the removal of the altered layer 96 using the ozone gas, the end point of the removal of the altered layer 96 can be appropriately detected for each substrate 9. Thus, the period during which the substrate 9 is heated at a relatively low temperature (the period during which the substrate 9 is arranged at the first processing position) can be prevented from being unnecessarily prolonged, thereby shortening the time required for removing the resist 95 on the substrate 9. In addition, cracking can be more reliably prevented.

[0053] By measuring the concentration of a predetermined component in the gas exhausted from the processing space 20 in parallel with the removal of the resist 95 (mainly the undeformed portion 97) using ozone gas, the end point of the removal of the resist 95 can be appropriately detected for each substrate 9. As a result, it is possible to prevent the period during which the substrate 9 is heated from being unnecessarily prolonged, thereby more reliably suppressing excessive oxidation of the substrate 9. In addition, the resist 95 can be removed more reliably.

[0054] In the pin lifting mechanism 32 having a stepping motor, the gap between the substrate 9 and the heating plate 4 can be freely changed. As a result, the temperature of the substrate 9 during the removal of the altered layer can be easily adjusted, and the explosion can be prevented more reliably.

[0055] Figure 8 FIG. 2 is a diagram showing another example of the resist removal apparatus 1. Figure 8 In the resist removal apparatus 1, a heating unit 24 is provided on the top plate 221 of the chamber cover 22. Figure 1 Similarly, in the resist removal apparatus 1 , the same reference numerals are given to the same structures.

[0056] The heating portion 24 provided on the chamber cover portion 22 surrounds the gas supply port 641 from which the ozone gas is ejected. Therefore, when ozone gas is supplied to the upper surface 91 of the substrate 9, the top plate portion 221 is heated by the heating portion 24, and the ozone gas ejected from the gas supply port 641 is also heated. As a result, the temperature of the ozone gas becomes higher, thereby promoting the generation of oxygen free radicals and the like. As a result, the degraded layer 96 can be removed from the substrate 9 arranged in the first processing position, and the undegraded portion 97 can be removed from the substrate 9 arranged in the second processing position in a short time without excessively increasing the temperature of the substrate 9. In this way, Figure 8 In the resist removal apparatus 1, the removal of the resist 95 can be promoted. In addition, the temperature rise of the substrate 9 caused by the heating of the top plate portion 221 by the heating portion 24 is slight, so when the degenerated layer 96 is removed, it is possible to prevent the substrate 9 arranged at the first processing position from cracking.

[0057] The resist removal apparatus 1 and the resist removal method described above can be modified in various ways.

[0058] The holding portion for holding the substrate 9 at the first processing position may be a member other than the plurality of lift pins 51. For example, a holding portion having a mechanism for holding the outer edge of the substrate 9 may be used in the resist removal apparatus 1. In this case, by designing the resist removal apparatus 1, the resist 95 may be removed by directing the main surface on which the resist 95 is formed downward or to the side. In addition, the holding portion may be moved relative to the heating plate 4, and a moving mechanism for moving the heating plate 4 in the vertical direction may be used.

[0059] The gas supply port 641 of the ozone gas supply unit 6 may be provided at a location other than the top plate portion 221 of the chamber cover 22 , for example, may be provided at the cover side portion 222 .

[0060] In the concentration measuring unit 72, only one of the ozone concentration and the carbon dioxide concentration may be measured, and based on the measured value of the concentration of the one, the end point of the removal of the altered layer 96 and the end point of the removal of the resist 95 may be detected. In addition, the concentration of the ions in the ion implantation performed using the pattern of the resist 95 may also be detected by the concentration measuring unit 72.

[0061] If the concentration of a predetermined component in the gas exhausted from the processing space 20 can be substantially measured, the concentration measuring unit 72 may be provided outside the gas exhaust pipe 712. For example, the concentration measuring unit 72 may be provided near the gas exhaust port 711 in the bottom plate 211.

[0062] The detection of the end point of the removal of the altered layer 96 by the control unit 10 may also be performed using various methods based on the measurement values ​​of the concentration measuring unit 72. For example, a reference profile representing a typical change in ozone concentration or carbon dioxide concentration from the start to the end of the removal of the altered layer 96 may be prepared, and the end point of the removal of the altered layer 96 may be detected by fitting the profile of the concentration change actually obtained to the reference profile. Similarly, the detection of the end point of the removal of the resist 95 (non-altered portion 97) by the control unit 10 may also be performed using various methods based on the measurement values ​​of the concentration measuring unit 72.

[0063] The configurations in the above-described embodiment and various modifications may be appropriately combined as long as they do not contradict each other.

[0064] Although the invention has been described and illustrated in detail, the above description is illustrative and not restrictive. Therefore, many modifications and embodiments are possible without departing from the scope of the present invention.

[0065] Description of reference numerals:

[0066] 1Resist removal device

[0067] 2 chambers

[0068] 4 Heating Plates

[0069] 6Ozone gas supply unit

[0070] 9 substrates

[0071] 10. Control Unit

[0072] 20 Processing Space

[0073] 24 Heating unit

[0074] 31 Cover lifting mechanism

[0075] 32-pin lifting mechanism

[0076] 51 lifting pin

[0077] 72Concentration measurement unit

[0078] 91 Upper surface

[0079] 95 resist

[0080] 96 Metamorphic Layer

[0081] 641 Gas supply port

[0082] Steps S11 to S21

Claims

1. A resist removal method for removing a resist from a substrate having a resist pattern on a main surface, wherein the resist has a deteriorated layer formed on the surface, wherein: The resist removal method has the following features: A) step of arranging the substrate and a heating plate heated to a predetermined temperature in a processing space blocked from the outside, and supplying ozone gas to the main surface to remove the altered layer; B) step, which is performed in parallel with the A) step, detecting the end point of the removal of the deteriorated layer by measuring the concentration of ozone gas in the gas exhausted from the processing space; as well as C) step, after the A) step, supplying ozone gas to the main surface to remove the resist.

2. The resist removal method according to claim 1, wherein: In the step B), the end point of the removal of the altered layer is detected based on the rate of change of the concentration of the ozone gas.

3. The resist removal method according to claim 1, wherein: The resist removal method further comprises a step of detecting an end point of the resist removal by measuring a concentration of a predetermined component in the gas exhausted from the processing space, which step is performed in parallel with the step C).

4. The resist removal method according to claim 1, wherein: In the step A), the substrate is disposed at a first processing position separated from the heating plate by a gap to remove the altered layer. In the step C), the resist is removed by placing the substrate at a second processing position where the gap is smaller than that of the first processing position.

5. The resist removal method according to claim 4, wherein: The processing space can be opened and closed. When the processing space is opened, the substrate is transferred from a holding portion holding the substrate to an external transport mechanism in a state where the substrate is arranged at a position farther from the heating plate than the first processing position.

6. The resist removal method according to any one of claims 1 to 5, wherein: In the processing space forming portion forming the processing space, a heating portion is provided around the supply port of the ozone gas.

7. The resist removal method according to any one of claims 1 to 5, wherein: The predetermined temperature of the heating plate is equal to or higher than a temperature at which the altered layer is cracked due to internal expansion in the resist having the altered layer formed thereon.

8. A resist removal device, wherein: The resist removal device comprises: A processing space forming part, forming a processing space blocked from the outside; A heating plate, disposed in the processing space and heated to a specified temperature; a holding portion that holds, in the processing space, a substrate having a resist pattern on a main surface, the resist having a degenerated layer formed on a surface; an ozone gas supply unit for supplying ozone gas to the main surface; a concentration measuring unit for measuring the concentration of ozone gas in the gas exhausted from the processing space; and The control unit detects an end point of the removal of the altered layer based on the measurement value of the concentration measuring unit, and then removes the resist using the ozone gas.

9. The resist removal apparatus according to claim 8, wherein: The control unit detects an end point of removal of the altered layer based on a rate of change in the concentration of the ozone gas.

10. The resist removal apparatus according to claim 8, wherein: The control section detects an end point of the removal of the resist based on the measurement value of the concentration measurement section.

11. The resist removal apparatus according to claim 8, wherein: The resist removal device further includes a moving mechanism that moves the holding portion relative to the heating plate. The control unit configures the substrate at a first processing position separated from the heating plate by a gap to remove the degraded layer using the ozone gas. Then, by controlling the moving mechanism, the substrate is configured at a second processing position where the gap is smaller than that of the first processing position to remove the anti-etching agent using the ozone gas.

12. The resist removal apparatus according to claim 11, wherein: The resist removal device further comprises an opening and closing mechanism for opening and closing the processing space; When the processing space is opened, the control unit arranges the substrate at a position farther from the heating plate than the first processing position, and transfers the substrate from the holding unit to an external transport mechanism.

13. The resist removal apparatus according to any one of claims 8 to 12, wherein: In the processing space forming portion, a heating portion is provided around the ozone gas supply port.

14. The resist removal apparatus according to any one of claims 8 to 12, wherein: The predetermined temperature of the heating plate is equal to or higher than a temperature at which the altered layer is cracked due to internal expansion in the resist having the altered layer formed thereon.

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