A high-precision multi-zone semiconductor heating platform control system

Abstract

The application relates to a high-precision multi-region semiconductor heating platform control system applied to the technical field of semiconductors, wherein through the arrangement of a partition heating unit and a local heating unit, when local solvent is not completely removed in the later period, the position of an abnormal point can be determined in time by cooperating with the arrangement of an abnormal monitoring unit, targeted heating is carried out through a thermal compensation disc, compared with the overall heating of the same region in the prior art, the influence on other normal regions is greatly reduced, the uniformity of the removal of the solvent on the photoresist surface is effectively improved, the photoresist film on the surface is formed more uniformly; in addition, after the abnormal monitoring unit monitors the abnormal point, the edge profile of the abnormal point can also be determined, when targeted heating is carried out, the actual heating area can be reduced again according to the profile by the thermal compensation disc, the accuracy of the secondary heating of the abnormal point is further improved, and the influence on other regions is further reduced.

Description

TECHNICAL FIELD

[0001] The application relates to a heating platform control system, in particular to a high-precision multi-zone semiconductor heating platform control system applied to the technical field of semiconductors. BACKGROUND

[0002] In the process of heating and baking to remove the solvent in the photoresist on the wafer surface, the temperature at the edge of the wafer is lower than that at the center due to the larger air flow speed at the edge closer to the exhaust port, leading to lower uniformity in the solvent removal process and affecting the uniformity of the photoresist film formation on the wafer surface. For example, the heating unit device of a photoresist baking process disclosed in Chinese Patent Specification No. CN116594269A and the photoresist baking machine disclosed in Chinese Patent Specification No. CN222529651U.

[0003] To solve the above problems, the existing technology adopts a zoned heating mode, that is, the heating temperature gradually increases from the center to the outside, so as to reduce the temperature difference on the wafer surface caused by exhaust, but after baking, the problem of incomplete removal of small-area local solvent often occurs. If the entire heating area is opened for heating, there is still the problem of high energy consumption, and the remaining solvent removal area is also easily overheated, affecting the quality of the photoresist film formation. In the existing technology, a matrix arrangement of heating elements is also used to realize regional heating, but in this way, the number of heating elements is too large, which is easy to damage and difficult to detect damage, and also easily leads to the problem of incomplete removal of local solvent. SUMMARY

[0004] In view of the above existing technology, the technical problem to be solved by the application is that when the area of the solvent is small and the solvent is not completely removed, the entire region is heated again, which not only easily causes high energy consumption, but also easily affects other solvent removal areas.

[0005] To solve the above problems, the application provides a high-precision multi-zone semiconductor heating platform control system, which comprises a control center installed on a heating platform and a wafer transfer module, an exhaust unit, a heating module and an abnormality monitoring unit connected with the control center, and further comprises a simulation platform for simulating the heating platform, wherein the simulation platform is connected with the control center, the heating module comprises a zoned heating unit and a local heating unit located below the zoned heating unit, the zoned heating unit is divided into a circular heating zone and a plurality of annular heating zones coaxial with the circular heating zone, and the outermost annular heating zone is equally divided into a plurality of arc-shaped heating zones with independent temperature control.

[0006] The wafer transfer module comprises a conveying disc mounted on the heating platform bottom plate through an electric sliding rail and three outer electric push rods arranged in a ring array, and the elongated ends of the three outer electric push rods are movably penetrated through the partition heating unit.

[0007] The abnormality monitoring unit comprises an infrared sensor mounted on the inner bottom wall of the baking cavity through a ring-shaped electric sliding rail, and the lower end of the infrared sensor is connected with a strong magnetic slider through an electric rotating shaft, the strong magnetic slider is matched with the ring-shaped electric sliding rail, the local heating unit comprises a ferromagnetic slider corresponding to the strong magnetic slider, an inner electric push rod fixedly connected to the lower end of the ferromagnetic slider, and a thermal compensation disc fixedly connected to the end of the inner electric push rod, the thermal compensation disc is located below the partition heating unit, and the thermal compensation disc and the partition heating unit are in contact with each other, a compensation cavity is opened in the heating platform, a ring-shaped sliding groove corresponding to the ring-shaped electric sliding rail is opened in the upper inner wall of the compensation cavity, the compensation cavity is located directly below the partition heating unit, and the thermal compensation disc is located in the compensation cavity.

[0008] In the above high-precision multi-zone semiconductor heating platform control system, through the setting of the partition heating unit and the local heating unit, when the local solvent is not completely removed in the later stage, the abnormal point and its contour can be determined in time by cooperating with the setting of the abnormality monitoring unit, and then the local heating unit can heat the abnormal point according to the contour. Compared with the prior art, the influence on other normal areas is greatly reduced, the energy consumption is effectively reduced, the uniformity of the solvent removal on the photoresist surface is effectively improved, and the photoresist film forming on the surface is more uniform.

[0009] As a further improvement of the present application, the smoke exhaust unit comprises two smoke exhaust hoods, a corrugated pipe fixedly connected between the two smoke exhaust hoods, and a smoke exhaust duct fixedly connected to the outer end of the smoke exhaust hood away from the conveying disc, the corrugated pipe communicates the two smoke exhaust hoods, the inner walls of the two smoke exhaust hoods are each opened with a plurality of air suction holes, the smoke exhaust duct penetrates the side wall of the baking cavity, the smoke exhaust hood connected with the smoke exhaust duct is fixed to the inner bottom wall of the baking cavity, the other smoke exhaust hood is connected to the inner top wall of the baking cavity through an electric push rod, and when the heights of the two are consistent, the inner walls of the two are complete annular and coaxial with the partition heating unit.

[0010] As a further improvement of the present application, the middle lines of the inner electric push rod and the thermal compensation disc and the laser emitting end of the infrared sensor are all directed towards the central axis of the partition heating unit.

[0011] As a further improvement of the present application, along the direction from the center to the outside, the heating temperature of the circular heating zone and the plurality of annular heating zones gradually increases, and the temperature difference between the edge and the middle of the wafer is not greater than 3℃.

[0012] As a further improvement of the present application, the heat compensation disc comprises a heat-conducting top disc facing the partition heating unit, a heat insulation layer below the heat-conducting top disc, a bottom disc fixedly attached to the lower end of the heat insulation layer, and a plurality of heating pieces fixedly embedded in the heat-conducting top disc respectively, and the lower end of each heating piece is provided with a selective power supply unit, and the selective power supply unit is arranged between the heat-conducting top disc and the heat insulation layer.

[0013] As a further improvement of the present application, the selective power supply unit comprises a T-shaped conductive column placed on the upper end of the heat insulation layer, two insulating columns fixedly connected to the lower end of the heating piece, and an elastic cylinder fixedly connected between the T-shaped conductive column and the insulating columns, and an electromagnetic piece fixedly embedded in the bottom disc, and the end of each insulating column extends between the heat insulation layer and the heat-conducting top disc, and the upper end of the T-shaped conductive column extends between the two insulating columns and does not contact the lower end of the heat-conducting top disc.

[0014] As a further improvement of the present application, the inner wall of the end of each insulating column close to each other is fixedly embedded with a conductive contact piece, the conductive contact piece is electrically connected to the heating piece, and the conductive contact piece is located above the T-shaped conductive column, and the bottom of the T-shaped conductive column is attached with a magnetic patch.

[0015] A high-precision multi-zone semiconductor heating platform control system, and a heating control method thereof, comprises the following steps:

[0016] S1, first, the wafer coated with photoresist is transferred to the baking cavity by the conveying disc, then the outer electric push rod is controlled to extend to pass through the conveying disc and lift the wafer, then the conveying disc and the outer electric push rod are controlled to reset in sequence, so that the wafer falls on the partition heating unit, and then the smoke exhaust hood close to the conveying disc is controlled to move downward and contact the bottom wall in the baking cavity;

[0017] S2, the control center controls the partition heating unit to start heating, and synchronously starts the smoke exhaust unit, during heating, the heating temperature of the circular heating zone and the plurality of annular heating zones is gradually increased from inside to outside, and the maximum temperature difference on the wafer surface is controlled to be not greater than 3℃;

[0018] S3, every certain period of time, the gas exhausted in the smoke exhaust unit is sampled, and the solvent characteristic ion fragments are analyzed by gas chromatography-mass spectrometry, until the solvent concentration in the solvent characteristic ion fragments is less than 50ppm;

[0019] S4, the wafer surface is scanned by the abnormality monitoring unit in sequence to detect the solvent volatilization condition of the wafer surface, when an abnormality that the solvent is not completely volatilized is detected, the abnormal point is heated in a targeted manner to assist the volatilization of the solvent, so as to improve the uniformity of the photoresist film on the wafer surface after baking.

[0020] As a further improvement of the present application, the specific operation of step S4 is as follows:

[0021] S41, first, simulate the three-dimensional image in the baking cavity through the simulation platform, then control the abnormal monitoring unit to move around the infrared sensor, make the infrared sensor scan each place on the wafer upper surface in turn, detect whether the solvent is uniformly removed at each place, when detecting that there is still solvent residue in a local place, the simulation platform marks the place on the simulated three-dimensional image as an abnormal point;

[0022] S42, continue to control the infrared sensor to rotate, and when rotating, constantly adjust the position of the emission end of the infrared sensor through the motorized rotating shaft, so that it always faces the abnormal point until the infrared sensor returns to the position where the abnormal point is first acquired, the simulation platform records the points of each abnormal data acquired during the rotation of the infrared sensor, and then connects the points in series to obtain the contour of the abnormal point on the simulation platform;

[0023] S43, then confirm the position of the abnormal point on the partition heating unit, then control the thermal compensation disc to move radially along the partition heating unit until it coincides with the abnormal point, obtain the coincidence of the thermal compensation disc and the abnormal point contour through the simulation platform, and control the center to control the heating sheet in the coincident area to be powered on according to the coincidence of the two obtained from the simulation platform, so as to realize precise heating.

[0024] As another improvement of the present application, in step S42, when there is a point with a large deviation from the position of the abnormal point among the points of each abnormal data acquired during the rotation of the infrared sensor, the point with a large deviation is removed and marked as another abnormal point, which can effectively avoid connecting two abnormal points at different positions in series, improve the accuracy of the finally obtained abnormal point contour, and then repeat steps S41-S43 again for the newly marked abnormal point until no abnormal point appears during the continuous rotation of the infrared sensor by 360°.

[0025] In summary, through the setting of the partition heating unit and the local heating unit, when the local solvent is not completely removed in the later stage, the position of the abnormal point can be determined in time in cooperation with the setting of the abnormal monitoring unit, and targeted heating can be performed through the thermal compensation disc. Compared with the overall heating of the same area in the prior art, the influence on other normal areas is greatly reduced, the uniformity of the solvent removal on the photoresist surface is effectively improved, and the formation of the surface resist film is more uniform. In addition, after the abnormal monitoring unit detects the abnormal point, the edge contour of the abnormal point can also be determined, and when the targeted heating is performed, the thermal compensation disc can further reduce the actual heating area according to the contour, further improve the accuracy of the secondary heating of the abnormal point, and further reduce the influence on other areas. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The module block diagram of the first embodiment of the present application;

[0027] Figure 2A perspective view of the heating platform of the first embodiment of the present application;

[0028] Figure 3 A side view of the heating platform of the first embodiment of the present application;

[0029] Figure 4 A schematic view of the heating process of the first embodiment of the present application;

[0030] Figure 5 A schematic view of the change of the smoke exhaust assembly of the first embodiment of the present application before and after the wafer is transported to the heating disc;

[0031] Figure 6 A schematic view of the partition of the partition heating unit of the first embodiment of the present application;

[0032] Figure 7 A schematic view of the cross section of the partition heating unit of the first embodiment of the present application;

[0033] Figure 8 A bottom view of the partition heating unit of the first embodiment of the present application;

[0034] Figure 9 A schematic view of the cross section of the partition heating unit of the second embodiment of the present application;

[0035] Figure 10 A schematic view of the cross section of the selection power supply unit of the second embodiment of the present application;

[0036] Figure 11 A schematic view of the cross section of the thermal compensation disc of the second embodiment of the present application;

[0037] Figure 12 A schematic view of the process of scanning the wafer surface by the abnormality monitoring unit of the second embodiment of the present application;

[0038] Figure 13 A schematic view of the cross section of the thermal compensation disc of the second embodiment of the present application;

[0039] Figure 14 A schematic view of the cross section of the thermal compensation disc of the second embodiment of the present application.

[0040] Explanation of the reference numerals in the figures:

[0041] 11 conveying disc, 12 outer electric push rod, 201 compensation cavity, 3 smoke exhaust unit, 31 smoke exhaust cover, 32 corrugated conduit, 33 smoke exhaust duct, 301 air suction hole, 4 partition heating unit, 41 circular heating zone, 42 annular heating zone, 5 infrared sensor, 501 strong magnetic slider, 61 ferromagnetic slider, 62 inner electric push rod, 7 thermal compensation disc, 71 heat-conducting top disc, 72 heating sheet, 731 heat insulation layer, 732 bottom disc, 741 insulating column, 742 T-shaped conductive column, 743 elastic cylinder, 744 electromagnetic sheet, 701 conductive contact sheet. DETAILED DESCRIPTION

[0042] Two embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0043] First embodiment:

[0044] Figures 1-3 A high-precision multi-zone semiconductor heating platform control system is shown, wherein a represents a heating platform body, and b represents a wafer. The control system includes a control center mounted on the heating platform, a wafer transfer module, a smoke exhaust unit 3, a heating module, and an abnormality monitoring unit connected in signal with the control center. The control system further includes a simulation platform for simulating the heating platform, which is connected in signal with the control center.

[0045] The wafer transfer module includes a conveying disc 11 mounted on the bottom plate of the heating platform through an electric sliding rail and three outer electric push rods 12 arranged in a ring array, wherein two outer electric push rods 12 are located on the same straight line, and the elongated ends of the three outer electric push rods 12 are movably penetrated through the partition heating unit 4. Figure 4 The conveying disc 11 is provided with two open long grooves, which correspond to the outer electric push rods 12. After transferring the wafer, the outer electric push rods 12 can penetrate through the conveying disc 11, lift the wafer, and separate from the conveying disc 11.

[0046] As shown in Figure 5 The smoke exhaust unit 3 includes two smoke exhaust covers 31, a corrugated conduit 32 fixedly connected between the two smoke exhaust covers 31, and a smoke exhaust duct 33 fixedly connected to the outer end of the smoke exhaust cover 31 away from the conveying disc 11. The corrugated conduit 32 communicates the two smoke exhaust covers 31. The inner walls of the two smoke exhaust covers 31 are each provided with a plurality of air suction holes 301. The smoke exhaust duct 33 penetrates through the side wall of the baking cavity. The smoke exhaust cover 31 connected with the smoke exhaust duct 33 is fixed to the inner bottom wall of the baking cavity. The other smoke exhaust cover 31 is connected to the inner top wall of the baking cavity through an electric push rod, and the heights of the two smoke exhaust covers 31 are consistent. The inner walls of the two smoke exhaust covers 31 are complete annular and coaxial with the partition heating unit 4. The movable smoke exhaust cover 31 is arranged to make the solvent volatilized on the wafer evenly diffuse to the surrounding and be absorbed and exhausted by the smoke exhaust cover 31 when the wafer is heated and baked, so that the temperature difference of the entire outer edge of the wafer is not too large. At the same time, the wafer transfer by the conveying disc 11 is not easily affected.

[0047] As Figures 7-8 , the heating module comprises a partition heating unit 4 and a local heating unit located below the partition heating unit 4, as Figure 6 , the partition heating unit 4 is divided into a circular heating area 41 and a plurality of annular heating areas 42 coaxial with the circular heating area 41, the outermost annular heating area 42 is divided into a plurality of arc-shaped heating areas with independent temperature control, and the heating temperature of the circular heating area 41 and the plurality of annular heating areas 42 gradually increases along the direction from the center to the outside, so that the partition heating can be realized, thereby relieving the problem of low temperature at the edge of the wafer due to exhaust, effectively ensuring that the wafer edge and the center maintain a low temperature difference, so that the temperature difference between the wafer edge and the center is not greater than 3℃, and the uniform evaporation of the solvent is facilitated.

[0048] As Figure 7 , the abnormality monitoring unit comprises an infrared sensor 5 installed on the inner bottom wall of the baking cavity through an annular electric sliding rail, a strong magnetic sliding block 501 is connected to the lower end of the infrared sensor 5 through an electric rotating shaft, the strong magnetic sliding block 501 is matched with the annular electric sliding rail, the local heating unit comprises a ferromagnetic sliding block 61 corresponding to the strong magnetic sliding block 501, an inner electric push rod 62 fixedly connected to the lower end of the ferromagnetic sliding block 61, and a thermal compensation disc 7 fixedly connected to the end of the inner electric push rod 62, the thermal compensation disc 7 is located below the partition heating unit 4, and the thermal compensation disc 7 and the partition heating unit 4 are in contact with each other, a compensation cavity 201 is opened in the heating platform, a ring-shaped sliding groove corresponding to the annular electric sliding rail is opened in the upper inner wall of the compensation cavity 201, the compensation cavity 201 is located directly below the partition heating unit 4, and the thermal compensation disc 7 is located in the compensation cavity 201, when the infrared sensor 5 rotates around the axis of the partition heating unit 4 to detect whether the solvent is removed uniformly, due to the magnetic attraction, the ferromagnetic sliding block 61 moves, and then the thermal compensation disc 7 moves with it, the middle lines of the inner electric push rod 62 and the thermal compensation disc 7 and the laser emitting end of the infrared sensor 5 are all directed to the central axis of the partition heating unit 4, so that the thermal compensation disc 7 and the infrared light beam emitted by the infrared sensor 5 coincide in the perspective angle, after the abnormal point is determined, the inner electric push rod 62 is directly controlled to elongate to drive the thermal compensation disc 7 to reach the abnormal point, which can effectively reduce the complexity of the thermal compensation disc 7 reaching the abnormal point for spot heating.

[0049] In summary, through the setting of the partition heating unit 4 and the local heating unit, when the local solvent is not completely removed in the later stage, the position of the abnormal point can be determined in time through the setting of the abnormality monitoring unit, and targeted heating is performed through the thermal compensation disc 7. Compared with the overall heating of the same area in the prior art, the influence on other normal areas is greatly reduced, the energy consumption is effectively reduced, the uniformity of the solvent removal on the photoresist surface is effectively improved, and the formation of the surface resist film is more uniform.

[0050] Second embodiment:

[0051] This embodiment is further improved on the basis of the first embodiment, and the remaining parts remain consistent with the first embodiment.

[0052] A high-precision multi-zone semiconductor heating platform control system, and a heating control method thereof, includes the following steps:

[0053] S1, first, the wafer coated with photoresist is transferred to the baking cavity by the conveying disc 11, then the outer electric push rod 12 is controlled to extend to pass through the conveying disc 11 and lift the wafer, then the conveying disc 11 and the outer electric push rod 12 are controlled to reset in sequence, so that the wafer falls on the partition heating unit 4, and then the smoke exhaust hood 31 close to the conveying disc 11 is controlled to move downward and contact the bottom wall in the baking cavity;

[0054] S2, the center controls the partition heating unit 4 to start heating, and synchronously starts the smoke exhaust unit, during heating, the heating temperature of the circular heating zone 41 and the plurality of annular heating zones 42 is gradually increased from inside to outside, and the maximum temperature difference on the wafer surface is controlled to be not greater than 3℃;

[0055] S3, every time interval, the gas exhausted in the smoke exhaust unit is sampled, the solvent characteristic ion fragments are analyzed by gas chromatography-mass spectrometry, and the solvent concentration in the solvent characteristic ion fragments is less than 50ppm until the solvent concentration is less than 50ppm;

[0056] S4, the wafer surface is scanned by the abnormal monitoring unit in sequence to detect the solvent volatilization of the wafer surface, when the abnormality that the solvent is not completely volatilized is detected, the abnormal point is heated to assist the volatilization of the solvent, so as to improve the uniformity of the film on the wafer surface after baking.

[0057] The specific operation of step S4 is as follows:

[0058] S41, first, the three-dimensional image in the baking cavity is simulated by the simulation platform, as shown in Figure 12 , then the abnormal monitoring unit is controlled to move around the infrared sensor 5, so that the infrared sensor 5 scans each place on the upper surface of the wafer in sequence, detects whether the solvent is uniformly removed at each place, when it is detected that the solvent is still locally residual, the simulation platform marks the place on the simulated three-dimensional image as an abnormal point;

[0059] S42, as shown in Figure 13 , c in the figure represents the abnormal point, and d represents the abnormal point contour, the infrared sensor 5 is continuously controlled to rotate, and during the rotation, the position of the emission end of the infrared sensor 5 is constantly adjusted by the electric rotating shaft, so that it is always directed to the abnormal point until the infrared sensor 5 returns to the position where the abnormal point is first acquired, the simulation platform records the points of each abnormal data acquired during the rotation of the infrared sensor 5, and then the points are connected in series to obtain the contour of the abnormal point on the simulation platform;

[0060] S43, such as Figure 14 Then, the location of the abnormal point on the partition heating unit 4 is confirmed. Then, the heat compensation disk 7 is controlled to move radially along the partition heating unit 4 until it coincides with the abnormal point. The overlap between the heat compensation disk 7 and the abnormal point is obtained through the simulation platform. Based on the overlap obtained from the simulation platform, the control center controls the heating element 72 in the overlap area to be energized to achieve precise heating.

[0061] In step S42, among the abnormal data points acquired during the rotation of the infrared sensor 5, if there is a point with a significant deviation from the abnormal point position, the point with the significant deviation is removed and marked as another abnormal point. This can effectively avoid connecting two abnormal points in different positions, improving the accuracy of the final obtained abnormal point contour. Then, steps S41-S43 are repeated for the newly marked abnormal points until no abnormal points appear after the infrared sensor 5 rotates 360° continuously.

[0062] Figures 9-11 As shown, the heat compensation plate 7 includes a heat-conducting top plate 71 facing the zoned heating unit 4, a heat insulation layer 731 located below the heat-conducting top plate 71, a base plate 732 fixedly attached to the lower end of the heat insulation layer 731, and a plurality of heating elements 72 respectively fixedly embedded in the heat-conducting top plate 71. Each heating element 72 has a corresponding power selection unit at its lower end. The power selection unit is located between the heat-conducting top plate 71 and the heat insulation layer 731. The power selection unit includes a T-shaped conductive post 742 placed on the upper end of the heat insulation layer 731, two insulating posts 741 fixedly connected to the lower end of the heating element 72, and insulating posts fixedly connected to the step of the T-shaped conductive post 742. The elastic cylinder 743 between 741 and the electromagnetic plate 744 fixedly embedded in the chassis 732, the ends of the two insulating pillars 741 extend to the space between the heat insulation layer 731 and the heat-conducting top plate 71, the upper end of the T-shaped conductive pillar 742 extends between the two insulating pillars 741 and does not contact the lower end of the heat-conducting top plate 71, the inner wall of the two insulating pillars 741 that are close to each other is fixedly embedded with conductive contact 701, the conductive contact 701 is electrically connected to the heating plate 72, and the conductive contact 701 is located above the T-shaped conductive pillar 742, the bottom of the T-shaped conductive pillar 742 is attached with a magnetic patch, and there is a magnetic repulsion between the magnetic patch and the energized electromagnetic plate 744.

[0063] After the overlapping area of the abnormal point profile and the heat compensation disc 7 is determined in the above step S4, the electromagnetic sheet 744 of the overlapping area can be controlled to be electrified, a magnetic repulsive force is generated on the T-shaped conductive column 742, the T-shaped conductive column 742 is pushed to move upward, and the T-shaped conductive column 742 is overlapped with the conductive contact sheet 701, so that the corresponding heating sheet 72 is electrified, thereby realizing the targeted heating of the abnormal point profile and the area within the profile of the wafer, further reducing the influence on other normal areas compared with the first embodiment, making the solvent removal effect better, and making the film forming more uniform.

[0064] After the abnormal point is monitored by the abnormal monitoring unit, the edge profile of the abnormal point can be determined, and when the targeted heating is performed, the heat compensation disc 7 can further reduce the actual heating area according to the profile, further improve the accuracy of the secondary heating of the abnormal point, and further reduce the influence on other areas.

[0065] It is worth noting that the magnetic structure involved in the two embodiments is made of high-temperature-resistant magnetic material, such as aluminum-nickel-cobalt (AlNiCo), Sm2Co 17 Samarium cobalt (maximum temperature resistance of about 800℃), and the like, so that the related magnetic structure is not easy to fail at high temperature when the solvent in the photoresist is removed by heating and baking (not more than 150℃).

[0066] In combination with the current actual demand, the above-mentioned embodiments adopted by the present application are not limited to the above, various changes within the knowledge range of those skilled in the art without departing from the concept of the present application still fall within the protection scope of the present application.

Claims

1. A high-precision multi-zone semiconductor heating platform control system, characterized in that: The control system comprises a control center installed on a heating platform, a wafer transfer module, an exhaust unit (3), a heating module and an abnormality monitoring unit connected with the control center, and a simulation platform for simulating the heating platform, which is connected with the control center, the heating module comprises a partition heating unit (4) and a local heating unit below the partition heating unit (4), the partition heating unit (4) is divided into a circular heating area (41) and a plurality of annular heating areas (42) coaxial with the circular heating area (41), and the outermost annular heating area (42) is equally divided into a plurality of arc-shaped heating areas with independent temperature control; The wafer transfer module comprises a conveying disc (11) installed on the bottom plate of the heating platform through an electric sliding rail and three outer electric push rods (12) arranged in a ring array, the elongated ends of the three outer electric push rods (12) are movably penetrated through the partition heating unit (4), and two open long grooves are formed in the conveying disc (11) and correspond to the outer electric push rods (12); The abnormality monitoring unit comprises an infrared sensor (5) installed on the inner bottom wall of the baking cavity through a ring-shaped electric sliding rail, a strong magnetic slider (501) connected with the lower end of the infrared sensor (5) through an electric rotating shaft, the strong magnetic slider (501) is matched with the ring-shaped electric sliding rail, the local heating unit comprises a ferromagnetic slider (61) corresponding to the strong magnetic slider (501), an inner electric push rod (62) fixedly connected with the lower end of the ferromagnetic slider (61), and a thermal compensation disc (7) fixedly connected with the end of the inner electric push rod (62), the thermal compensation disc (7) is located below the partition heating unit (4) and in contact with the partition heating unit (4), a compensation cavity (201) is formed in the heating platform, a ring-shaped sliding groove corresponding to the ring-shaped electric sliding rail is formed in the inner wall of the compensation cavity (201), and the compensation cavity (201) is located directly below the partition heating unit (4) and the thermal compensation disc (7) is located in the compensation cavity (201); The thermal compensation disc (7) comprises a heat-conducting top disc (71) facing the partition heating unit (4), a heat insulation layer (731) below the heat-conducting top disc (71), a bottom disc (732) fixedly attached to the lower end of the heat insulation layer (731), and a plurality of heating sheets (72) fixedly embedded in the heat-conducting top disc (71), respectively, a selective power supply unit is arranged at the lower end of each heating sheet (72), and the selective power supply unit is arranged between the heat-conducting top disc (71) and the heat insulation layer (731). The selection energizing unit comprises a T-shaped conductive column (742) placed on the upper end of the heat insulation layer (731), two insulating columns (741) fixedly connected at the lower end of the heating sheet (72), and an elastic cylinder (743) fixedly connected between the T-shaped conductive column (742) and the insulating columns (741), and an electromagnetic sheet (744) fixedly embedded in the bottom disc (732), the end of each of the two insulating columns (741) extending between the heat insulation layer (731) and the heat-conducting top disc (71), and the upper end of the T-shaped conductive column (742) extending between the two insulating columns (741) and not in contact with the lower end of the heat-conducting top disc (71). The inner wall of the end of each of the two insulating columns (741) is fixedly embedded with a conductive contact sheet (701), the conductive contact sheet (701) is electrically connected with the heating sheet (72), and the conductive contact sheet (701) is located above the T-shaped conductive column (742), and the bottom of the T-shaped conductive column (742) is attached with a magnetic sheet.

2. The high-precision multi-zone semiconductor heating platform control system according to claim 1, wherein: The smoke exhaust unit (3) comprises two smoke exhaust hoods (31), a corrugated pipe (32) fixedly connected between the two smoke exhaust hoods (31), and a smoke exhaust duct (33) fixedly connected to the outer end of the smoke exhaust hood (31) away from the conveying disc (11), the corrugated pipe (32) being communicated with the two smoke exhaust hoods (31), the inner wall of each of the two smoke exhaust hoods (31) being provided with a plurality of air inlet holes (301), the smoke exhaust duct (33) penetrating the side wall of the baking cavity, the smoke exhaust hood (33) connected with the smoke exhaust duct (33) being fixed to the inner bottom wall of the baking cavity, and the other smoke exhaust hood (31) being connected to the inner top wall of the baking cavity by an electric push rod, and when the heights of the two smoke exhaust hoods (31) are consistent, the inner walls of the two smoke exhaust hoods (31) are complete annular and coaxial with the zoned heating unit (4).

3. The high-precision multi-zone semiconductor heating platform control system according to claim 1, wherein: The middle lines of the inner electric push rod (62) and the heat compensation disc (7) and the laser emitting end of the infrared sensor (5) are all directed to the middle axis of the zoned heating unit (4).

4. The high-precision multi-zone semiconductor heating platform control system according to claim 1, wherein: In the direction from the center to the outside, the heating temperature of the circular heating zone (41) and the plurality of annular heating zones (42) gradually increases, and the temperature difference between the edge and the middle of the wafer is not greater than 3℃.

5. The high-precision multi-zone semiconductor heating platform control system according to claim 1, wherein: The heating control method comprises the following steps: S1, first, the wafer coated with photoresist is transferred into the baking cavity by the conveying disc (11), then the outer electric push rod (12) is controlled to be elongated to pass through the conveying disc (11) and lift the wafer, then the conveying disc (11) and the outer electric push rod (12) are controlled to be reset in sequence, so that the wafer falls on the zoned heating unit (4), then the smoke exhaust hood (31) close to the conveying disc (11) is controlled to move downward and contact with the inner bottom wall of the baking cavity; S2, the central control zoned heating unit (4) is controlled to start heating, and the smoke exhaust unit is started synchronously, during heating, the heating temperature of the circular heating zone (41) and the plurality of annular heating zones (42) is gradually increased from the inside to the outside, and the maximum temperature difference on the wafer surface is controlled to be not greater than 3℃; S3, every certain period of time, the gas exhausted in the smoke exhaust unit is sampled, the solvent characteristic ion fragments are analyzed by gas chromatography-mass spectrometry, until the solvent concentration in the solvent characteristic ion fragments is less than 50ppm. S4, the abnormal monitoring unit scans the wafer surface in sequence, detects the solvent volatilization of the wafer surface, and when an abnormality of incomplete solvent volatilization is detected, the abnormal point is heated to assist the volatilization of the solvent, so as to improve the uniformity of the wafer surface after baking.

6. The high-precision multi-zone semiconductor heating platform control system according to claim 5, wherein: The specific operation of the step S4 is: S41, first, simulate the three-dimensional image in the baking cavity through the simulation platform, then control the abnormal monitoring unit to move around the infrared sensor (5), so that the infrared sensor (5) scans each part of the upper surface of the wafer in sequence, detects whether the solvent is uniformly removed, when it is detected that there is still solvent residue in the local, the simulation platform marks the place on the simulated three-dimensional image, which is marked as an abnormal point; S42, continue to control the rotation of the infrared sensor (5), and when rotating, constantly adjust the position of the emission end of the infrared sensor (5) through the motorized shaft, so that it always faces the abnormal point until the infrared sensor (5) returns to the position where the abnormal point is first acquired, and record the points of each abnormal data obtained during the rotation of the infrared sensor (5), then connect the points to obtain the contour of the abnormal point; S43, then confirm the position of the abnormal point on the partition heating unit (4), then control the thermal compensation disc (7) to move radially along the partition heating unit (4) until it coincides with the abnormal point, obtain the coincidence of the thermal compensation disc (7) and the abnormal point contour through the simulation platform, control the center to control the heating sheet (72) in the coincidence area to be powered on according to the coincidence of the two obtained from the simulation platform, so as to realize precise heating.

7. The high-precision multi-zone semiconductor heating platform control system according to claim 6, wherein: In step S42, when there are points with large deviation from the position of the abnormal point in the points of each abnormal data obtained during the rotation of the infrared sensor (5), the points with large deviation are removed and marked as another abnormal point, then the steps S41-S43 are repeated again for the newly marked abnormal point until there is no abnormal point in the continuous rotation of the infrared sensor (5) for 360°.

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