Semiconductor manufacturing equipment and wafer temperature control method

Abstract

Provided is technology for easily controlling the temperature of a wafer within a processing chamber into which a gas is introduced.　This semiconductor manufacturing device comprises: a wafer heater that utilizes electromagnetic waves; and a control circuit. The control circuit uses information representing relationships among the type of gas introduced into a processing chamber, the pressure of the gas around a wafer, the height of a pusher pin that determines spacing between the wafer and a stage, the output of the heater, a target temperature for the wafer, and a target temperature reaching time, which is the time it takes for the temperature of the wafer to reach the target temperature, to determine, in advance, a pusher pin height whereby the target temperature reaching time is no longer than an allowed time for a gas type, gas pressure, and wafer target temperature that have been set. The control circuit, after controlling the height of the pusher pin to the determined height, controls at least one among the heater output and the pusher pin height.

Description

[Technical Field]

[0001] The present invention relates to a semiconductor manufacturing apparatus and a wafer temperature control method. [Background technology]

[0002] Gas etching is becoming increasingly important in the isotropic etching process of three-dimensional semiconductor fabrication. In particular, gas etching under high temperature and pressure environments is known to have advantages in terms of etching rate, i.e., shortening the etching time required. In gas etching, physical parameters such as gas pressure and wafer temperature significantly affect the chemical reaction, so controlling these parameters is important.

[0003] A common method for heating a wafer to control its temperature is to heat the stage that supports the wafer. However, this method tends to reduce wafer processing throughput because the stage has a large heat capacity and it takes a long time to heat the wafer. In response to this, for example, Patent Document 1 describes a method for heating a wafer more quickly by irradiating the wafer with electromagnetic waves such as infrared light. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6488164 Summary of the Invention [Problem to be solved by the invention]

[0005] However, according to the results of investigations by the present inventors, when a method of heating a wafer by irradiating it with electromagnetic waves is applied in a processing chamber into which a process gas is introduced, it has been found that it is difficult to control the wafer temperature because the wafer temperature changes depending on the gas pressure. When it becomes difficult to control the wafer temperature in a processing chamber into which a gas is introduced, it becomes difficult to shorten the time required for the wafer temperature to reach a target temperature, and it is not possible to improve productivity in semiconductor processing using gas, such as gas etching.

[0006] SUMMARY OF THE INVENTION An object of the present invention is to provide a technique that facilitates temperature control of a wafer in a processing chamber to which gas is introduced. [Means for solving the problem]

[0007] a wafer support mechanism at least partially disposed inside the processing chamber, configured to support the wafer and be capable of being raised and lowered, and capable of adjusting the distance between the wafer and the stage; a gas supply and exhaust system capable of adjusting the gas pressure inside the processing chamber; a memory circuit that stores relationship information representing the relationship between the output of the heater, the type of gas, the gas pressure inside the processing chamber, the target temperature of the wafer, the distance between the wafer and the stage, and the time required for the temperature of the wafer to reach the target temperature; and a control circuit that uses the relationship information based on the set type of gas, the gas pressure, and the target temperature of the wafer to determine the distance between the wafer and the stage so that the time required for the temperature of the wafer to reach the set target temperature is equal to or shorter than a set time, and controls the wafer support mechanism to maintain the determined distance between the wafer and the stage.

[0008] One embodiment of the present invention is a wafer temperature control method comprising the steps of: a wafer support mechanism disposed inside a processing chamber and configured to be able to rise and fall, supporting a wafer above a stage; a gas supply and exhaust system adjusting the gas pressure inside the processing chamber; a memory circuit storing relationship information representing the relationship between the output of an electromagnetic wave wafer heater, the type of gas, the gas pressure inside the processing chamber, the target temperature of the wafer, the distance between the wafer and the stage, and the time required for the temperature of the wafer to reach the target temperature; a control circuit using the relationship information based on the set type of gas, the gas pressure, and the target temperature of the wafer, determining the distance between the wafer and the stage so that the time required for the temperature of the wafer to reach the set target temperature is equal to or less than a set time; and a control circuit controlling the wafer support mechanism so that the distance between the wafer and the stage is the determined distance. [Effects of the Invention]

[0009] According to one embodiment of the present invention, it is possible to provide a technology that facilitates temperature control of a wafer in a processing chamber into which gas has been introduced. Note that problems, configurations, and effects other than those described above will become apparent from the following description of the embodiment. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 10 is a diagram showing an example of a graph showing the relationship between the average temperature of a wafer and the gas pressure around the wafer under constant heating conditions. [Figure 2] FIG. 1 is a diagram schematically illustrating an example of a main part of a semiconductor manufacturing apparatus. [Figure 3] FIG. 1 is a diagram schematically illustrating an example of a main part of a semiconductor manufacturing apparatus. [Figure 4] 1 is a side view schematically showing the configuration of a semiconductor manufacturing apparatus according to a first embodiment. [Figure 5] FIG. 10 is a diagram showing an example of the dependency of the pusher pin height on the time it takes for the wafer to reach a target temperature. [Figure 6] 10 is a graph schematically showing the relationship between the target temperature of a wafer and the time it takes to reach the target temperature when the wafer is heated with the pusher pins set to different heights. [Figure 7] FIG. 10 is a diagram showing that the relationship between the target temperature of the wafer and the time it takes to reach the target temperature varies depending on the height of the pusher pin. [Figure 8] FIG. 10 is a diagram showing that the relationship between the target temperature of the wafer and the time it takes to reach the target temperature varies depending on the height of the pusher pin. [Figure 9] 1 is a flowchart illustrating an example of a process flow in the semiconductor manufacturing apparatus according to the first embodiment. FIG. 2 is a diagram schematically illustrating changes over time in the gas pressure in the process chamber, the height of the pusher pin, and the output of the wafer heater during etching. [Figure 10] 4 is a time chart schematically showing a flow of an example of an operation according to the first embodiment of the present invention. [Figure 11] FIG. 10 is a cross-sectional view showing a schematic configuration of a semiconductor manufacturing apparatus according to a second embodiment. [Figure 12] 10 is a flowchart showing an example of the flow of operations in the semiconductor manufacturing apparatus according to the second embodiment. [Figure 13] 10 is a graph schematically showing the relationship between the change over time of the height of the pusher pin and the change over time of the temperature of the wafer according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] <Background of the study by the inventors> The semiconductor manufacturing process includes processes such as pattern transfer, etching, cleaning, and planarization for wafers made of, for example, silicon, gallium arsenide, etc. Here, we focus on the equipment and techniques used in the etching process.

[0012] As described above, when a method for heating by irradiating electromagnetic waves is applied to a wafer in a processing chamber containing a process gas, it has been found that the wafer temperature varies depending on the gas pressure in the processing chamber, making it difficult to control the wafer temperature. For example, in a semiconductor manufacturing apparatus for etching, if the processing chamber is in a high-pressure environment where the gas pressure is high, it becomes difficult to control the wafer temperature using a wafer heater that utilizes electromagnetic waves. Here, the gas may be, for example, argon gas or helium gas. A high-pressure environment is, for example, an environment in which the gas pressure inside the processing chamber is a predetermined pressure of 10 Pa or more and less than atmospheric pressure. The wafer temperature is, for example, a predetermined temperature of 100°C or more and 700°C or less.

[0013] Figure 1 shows an example of a graph showing the relationship between the average wafer temperature and the gas pressure around the wafer under constant heating conditions. For example, as shown in Figure 1, increasing the gas pressure around the wafer under constant heating conditions causes the average wafer temperature to decrease. Furthermore, the relationship between the gas pressure around the wafer and the average wafer temperature is not linear; as the gas pressure around the wafer is gradually increased, the average wafer temperature initially decreases sharply and then decreases more gradually.

[0014] This mechanism will be explained using the diagram.

[0015] 2 and 3 are diagrams showing an example of the main components of a semiconductor manufacturing apparatus. As shown in FIGS. 2 and 3, the semiconductor manufacturing apparatus 101 includes an electromagnetic wave wafer heater 102, a stage 103 without an electrostatic chuck mechanism, and proximity pins 105 arranged above the stage 103 and supporting a wafer 104. The circles shown between the wafer 104 and the stage 103 are schematic representations of gas molecules 106. A cooler 107 is connected to the stage 103, allowing cooling of the stage 103. Note that the height of the proximity pins 105 in these figures is exaggerated to facilitate understanding.

[0016] As shown in FIG. 2, in a low-pressure environment where the gas pressure is relatively low, there are fewer gas molecules 106, which are the medium for heat exchange between the wafer 104 and the stage 103. This reduces the efficiency with which the stage 103 cools the wafer 104, making it easier for the wafer heater 102 to heat the wafer 104. On the other hand, in a high-pressure environment where the gas pressure is relatively high, there are more gas molecules 106, which are the medium for heat exchange between the wafer 104 and the stage 103, as shown in FIG. 3. This increases the efficiency of heat transfer between the wafer 104 and the stage 103, causing a drop in wafer temperature. This can lead to problems such as insufficient output from the wafer heater 102 to achieve the desired processing process or taking too long to heat the wafer 104, resulting in reduced productivity in semiconductor processing.

[0017] In view of the above circumstances, the present inventors have conducted extensive research and have found a technique for easily controlling the wafer temperature in a processing chamber into which gas is introduced.

[0018] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, elements, members, or parts having the same configuration are designated by the same reference numerals, and repeated description will be omitted unless necessary. Furthermore, the following embodiments are merely examples, and do not limit the technical scope of the present invention in any way.

[0019] (First embodiment) A first embodiment of the present invention will be described.

[0020] <Configuration example of semiconductor manufacturing apparatus according to the first embodiment> 4 is a side view schematically illustrating the configuration of a semiconductor manufacturing apparatus 1 according to a first embodiment. As shown in FIG. 4, the semiconductor manufacturing apparatus 1 includes a processing chamber 2 made of, for example, aluminum or the like, and having a generally cylindrical container shape with an opening at the top. The processing chamber 2 is provided with a plate-shaped stage 4 for placing a wafer 3 therein. The stage 4 is connected to the bottom of the processing chamber 2 by a support member 5. The stage 4 is a proximity stage that does not have an electrostatic chuck mechanism.

[0021] A flow path 6 through which a fluid such as water flows is provided inside the stage 4, and the temperature of the upper surface of the stage 4 can be adjusted by adjusting the temperature of the fluid flowing through the flow path 6. A fluid temperature adjustment circuit 18 that adjusts the temperature of the fluid flowing through the flow path 6 is provided outside the processing chamber 2. The flow path 6 and the fluid temperature adjustment circuit 18 are connected through the sidewall or bottom of the processing chamber 2. The flow path 6 and the processing chamber 2 are sealed. The fluid, the flow path 6, and the fluid temperature adjustment circuit 18 are an example of a "temperature adjustment system" in this application.

[0022] The stage 4 is formed with a plurality of through-holes that penetrate up and down, i.e., vertically. A plurality of pusher pins 7 are provided to be inserted into these through-holes. There are, for example, three or more pairs of pusher pins 7 and their corresponding through-holes. The wafer 3 is placed on the upper tips of these pusher pins 7. A drive shaft 8 is provided below the stage 4 so as to penetrate up and down through the bottom of the processing chamber 2. These pusher pins 7 are connected to the drive shaft 8.

[0023] A drive mechanism 9 is provided below the processing chamber 2. The drive shaft 8 is connected to this drive mechanism 9 and is configured to be able to move up and down. The drive mechanism 9 is composed of, for example, a stepping motor, an actuator, etc. By driving the drive shaft 8 up and down using the drive mechanism 9, i.e., by raising and lowering it, the height of the pusher pins 7 can be adjusted, and the distance d between the wafer 3 supported by the pusher pins 7 and the upper surface of the stage 4 can be controlled.

[0024] The gap between the drive shaft 8 and the through-hole at the bottom of the processing chamber 2 through which the drive shaft 8 is inserted is sealed, and when the opening formed at the top of the processing chamber 2 is closed, the airtightness of the inside of the processing chamber 2 is maintained. Furthermore, the drive mechanism 9 is not limited to a stepping motor, and a simpler drive mechanism may be used.

[0025] The pusher pin 7, the drive shaft 8, and the drive mechanism 9 are an example of the "wafer support mechanism" in this application.

[0026] A top plate 10 is installed on the upper side, i.e., the ceiling side, of the processing chamber 2. The top plate 10 is made of, for example, quartz or the like, and has the property of transmitting electromagnetic waves. A wafer heater 11 is installed above the top plate 10, which irradiates the wafer 3 with electromagnetic waves, such as infrared rays.

[0027] An opening 12 is formed in the sidewall of the processing chamber 2 for supplying gas into the interior of the processing chamber 2. A gas supply source, such as a gas cylinder, is installed outside the processing chamber 2. The opening 12 and the gas supply source 13 are connected via a mass flow controller 14. The operation of the mass flow controller 14 controls the flow rate of the gas so that the gas can be introduced into the processing chamber 2.

[0028] An opening 15 is formed at the bottom of the processing chamber 2 for discharging gases and particles from inside the processing chamber 2. A dry pump 17 is installed outside the processing chamber 2 for sucking in gases and particles. The opening 15 and the dry pump 17 are connected via a variable valve 16. While the dry pump 17 is operating, the gases and particles from inside the processing chamber 2 are discharged by the operation of the variable valve 16, thereby controlling the gas pressure inside the processing chamber 2. The opening 12, the gas supply source 13, the mass flow controller 14, the opening 15, the variable valve 16, and the dry pump 17 are a mechanism that can adjust the gas pressure inside the processing chamber 2, and are an example of a "gas supply and exhaust system" in this application.

[0029] The semiconductor manufacturing equipment 1 includes a control circuit 19, a memory circuit 20, and an input / output circuit 21. The memory circuit 20 is a circuit that stores various information required for processing. A database DB related to wafer processing conditions in the semiconductor manufacturing equipment 1 is stored in the memory circuit 20. The control circuit 19 references the database DB stored in the memory circuit 20 to control the fluid temperature adjustment circuit 18, the drive mechanism 9, the wafer heater 11, the mass flow controller 14, and the variable valve 16. The input / output circuit 21 is electrically connected to the control circuit 19, and receives input from a user and sends the information to the control circuit 19, and outputs information sent from the control circuit 19 to the user.

[0030] The control circuit 19 is configured with, for example, semiconductor integrated circuits such as a CPU (Central Processing Unit) and an MCU (Micro Controller Unit). The storage circuit 20 is configured with, for example, a RAM (Random Access Memory), a ROM (Read Only Memory), an SSD (Solid State Drive), an HDD (Hard Disk Drive), etc. The input / output circuit 21 is configured with, for example, a keyboard, a mouse, and a monitor display, or a liquid crystal touch panel, etc.

[0031] <Database creation example> Next, an example of creating a database DB will be described. The database DB is an example of "relationship information" in the present application.

[0032] Figure 5 shows an example of the dependency of pusher pin height on the time it takes for a wafer to reach a target temperature. Here, the time it takes for the wafer temperature to reach the target temperature. The example shown in Figure 5 represents the results obtained when an experiment was conducted under the following conditions:

[0033] The wafer temperature was measured using a thermocouple, and the measured wafer temperature information was used to adjust the output of the infrared lamp (wafer heater) through PID control to maintain the wafer temperature at 300°C. Argon gas was introduced into the processing chamber, and the pressure inside the processing chamber, i.e., the gas pressure around the wafer, was maintained at 1000 Pa by controlling the opening of the variable valve. The temperature of the top surface of the stage was adjusted to 20°C. Under these conditions, it can be seen that the time it took for the wafer to reach the target temperature was shortest when the pusher pin height, i.e., the distance between the top surface of the stage and the backside of the wafer, was 1 mm. In this example, PID control was used, but it can be seen that there is a pusher pin height that shortens the time it takes for the wafer to reach the target temperature, depending on the gas pressure and wafer temperature.

[0034] Figure 6 is a graph that schematically shows the relationship between the target wafer temperature and the time it takes to reach the target temperature when the wafer is heated with multiple pusher pin heights. The graph in Figure 6 shows an example where the pusher pin heights are set to three levels: P1, P2, and P3. The relationship between the pusher pin heights P1, P2, and P3 is P1>P2>P3, with P1 being the highest and P3 being the lowest. The graph in Figure 6 shows that for each pusher pin height, there is a wafer temperature that results in the shortest time to reach the target temperature, and that the time to reach the target temperature can be expressed as a function with a minimum value using the wafer target temperature as a parameter.

[0035] Here, if time t1 is set as the standard for the time to reach the target temperature, it is possible to determine wafer temperature ranges ΔT1, ΔT2, and ΔT3 such that the time to reach the target temperature is equal to or shorter than the set time t1 at each pusher pin height P1, P2, and P3. Because the wafer temperature range within which the time to reach the target temperature is equal to or shorter than time t1 differs for each pusher pin height, if the time to reach the target temperature is equal to or shorter than time t1 is set as the acceptable standard, it is possible to determine a relatively appropriate pusher pin height that satisfies the acceptable standard based on the desired target temperature of the wafer.

[0036] 7 and 8 are diagrams showing that the relationship between the wafer target temperature and the time it takes to reach the target temperature varies depending on the height of the pusher pin. FIGS. 7 and 8 schematically show the relationship between the wafer target temperature and the time it takes to reach the target temperature when the wafer is heated with the pusher pin heights set to P4 and P5. FIG. 7 shows the case where the gas pressure in the processing chamber is relatively low, while FIG. 8 shows the case where the gas pressure in the processing chamber is relatively high. Here, the relationship between the pusher pin heights P4 and P5 is P4>P5, with P4 being higher than P5.

[0037] As shown in Figures 2 and 3, when the gas pressure changes, the heat transfer efficiency between the wafer and the stage changes, and even if the pusher pin height is the same, the relationship between the wafer temperature and the time it takes for the wafer to reach the target temperature changes. The pusher pin height is gradually changed to investigate the relationship between the wafer target temperature and the time it takes for the wafer to reach the target temperature, and this is done under various conditions, such as various gas types, gas pressures, and heater output power. This allows the relationship between the wafer target temperature and the time it takes for the wafer to reach the target temperature under various conditions to be compiled into a database. Then, by referencing this database, it becomes possible to select the optimal pusher pin height and heater output power conditions that minimize the time it takes to reach the target temperature for the desired gas type, desired gas pressure in the processing chamber, and desired wafer target temperature.

[0038] The database DB created in this manner is stored in advance in the storage circuitry 20. The database DB may be, for example, a table in which an appropriate Pischer pin height and wafer heater output are associated with any combination of gas type, gas pressure, and wafer target temperature. The database DB may also be a function or algorithm that receives the gas type, gas pressure, and wafer target temperature as input and outputs the appropriate Pischer pin height and wafer heater output. Alternatively, the database DB may be information that represents the relationship between each parameter, such as the gas type, gas pressure, wafer target temperature, Pischer pin height, and wafer heater output.

[0039] <Process flow in semiconductor manufacturing apparatus according to the first embodiment> Next, the flow of processing in the semiconductor manufacturing apparatus 1 having the above configuration will be described.

[0040] FIG. 9 is a flowchart showing an example of the flow of processing in the semiconductor manufacturing apparatus 1 according to the first embodiment.

[0041] 9, first, in step S101, a wafer is placed on a stage. Specifically, a robot or the like transports the wafer 3 from the load lock chamber to the processing chamber 2 and places the wafer 3 on the stage 4. The control circuit 19 controls the fluid temperature adjustment circuit to maintain the temperature of the stage 4 at a set temperature, for example, 20°C.

[0042] Next, in step S102, the output of the wafer heater and the height of the pusher pins are determined based on the set type of gas, the gas pressure in the processing chamber 2, and the target temperature of the wafer. Specifically, the control circuit 19 refers to the database DB for the set type of gas, gas pressure, and target temperature of the wafer, and determines the output of the wafer heater 11 and the height of the pusher pins 7 so that the time to reach the target temperature is within the set allowable time.

[0043] Next, in step S103, control is performed to adjust the pusher pin to the height determined in step S102. Specifically, the control circuit 19 controls the drive mechanism 9 to adjust the height of the pusher pin to the height determined in step S102.

[0044] Next, in step S104, the pressure inside the processing chamber is controlled to be adjusted to the set pressure. Specifically, the control circuit 19 controls the gas flow rate of the mass flow controller 14 connected to the gas supply source 13 and the valve opening of the variable valve 16 connected to the operating dry pump 17, thereby introducing gas into the processing chamber 2 and adjusting the internal gas pressure to be the set pressure.

[0045] Next, in step S105, the output of the wafer heater is adjusted to the output determined in step S102. Specifically, the control circuit 19 controls the wafer heater 11 to adjust the output of the wafer heater 11 to the output determined in step S102, and heats the wafer 3.

[0046] After the wafer heating is completed, the pusher pins are lowered in step S106 to cool the wafer on the stage. Specifically, the control circuit 19 controls the drive mechanism 9 and the fluid temperature adjustment circuit 18 to lower the pusher pins 7 until the wafer 3 is placed on the stage, adjust the temperature of the stage 4, and cool the wafer 3 on the stage 4.

[0047] Next, in step S107, it is determined whether or not the process needs to be repeated. Specifically, the control circuit 19 determines whether or not to repeat the process as necessary based on the set sequence or whether or not an error signal has been transmitted. If it is determined that the process should be repeated (S107: Yes), the process proceeds to step S102. If it is determined that the process should not be repeated (S107: No), the etching process of the wafer 3 is terminated.

[0048] When the etching process of the wafer 3 is completed, the control circuit 19 controls each part to stop the supply of gas into the processing chamber 2, the output of the wafer heater 11, etc., and the robot removes the wafer 3 from the processing chamber 2.

[0049] <Changes over time in gas pressure, pusher pin height, and wafer heater output> The changes over time in the gas pressure, the height of the pusher pin, and the output of the wafer heater during the etching process will now be described.

[0050] 10 is a diagram showing the time variations of the gas pressure in the processing chamber, the height of the pusher pin, and the output of the wafer heater during the etching process. The step numbers at the top correspond to the time periods of the corresponding steps in the flowchart shown in FIG.

[0051] As shown in FIG. 10, during the time period corresponding to S103, the pusher pins 7 are raised and adjusted to the height determined in S102. During the time period corresponding to step S104, gas is introduced into the processing chamber 2, and the gas pressure in the processing chamber 2 is adjusted to a set pressure. The height of the pusher pins 7 is maintained. During the time period corresponding to step S105, the output of the wafer heater 11 is adjusted to the output determined in S102. The gas pressure in the processing chamber 2 and the height of the pusher pins 7 are maintained. During the time period corresponding to step S106, the gas in the processing chamber 2 is exhausted, and the gas pressure decreases. The pusher pins 7 are lowered, and the tips supporting the wafer 3 are positioned below the upper surface of the stage 4. The output of the wafer heater 11 is reduced to zero.

[0052] In addition, when the pusher pins 7 are moved up and down, i.e., raised and lowered, in a high-pressure environment during cooling of the wafer in step S106, there is a possibility that misalignment may occur between the wafer 3 and the stage 4 due to the influence of gas molecules present between the backside of the wafer 3 and the upper surface of the stage 4. In order to reduce this wafer misalignment, step S108, which is a process of reducing the gas pressure in the processing chamber 2, may be inserted between steps S105 and S106.

[0053] According to the first embodiment, a technology can be provided that facilitates wafer temperature control in a processing chamber into which gas has been introduced. More specifically, according to the first embodiment, the height of the pusher pins 7 and the output of the wafer heater 11 can be determined in advance based on the set gas type, gas pressure inside the processing chamber 2, and target temperature of the wafer 3, by referencing the database, so as to shorten the time required for the temperature of the wafer 3 to reach and stabilize at the target temperature. This makes it possible to quickly reach the target temperature over a wide range of gas pressures and wafer temperatures, thereby increasing the productivity of semiconductor processing. As a result, improvements in semiconductor processing throughput and etching controllability can be expected.

[0054] The effects of the first embodiment are particularly effective in high-temperature or high-pressure environments where wafer temperature control is difficult, such as when the wafer temperature is a predetermined temperature of 100°C or higher and 700°C or lower, or when the gas pressure is a predetermined pressure of 10 Pa or higher and atmospheric pressure or lower.

[0055] (Second embodiment) <Configuration example of semiconductor manufacturing apparatus according to the second embodiment> Fig. 11 is a cross-sectional view showing a schematic configuration of a semiconductor manufacturing apparatus according to the second embodiment. In the semiconductor manufacturing apparatus 22 shown in Fig. 11, the processing chamber 2, the support member 5, the top plate 10, the gas supply and exhaust system, etc. are omitted, and the shapes, functions, etc. of the omitted parts are the same as the corresponding parts in the semiconductor manufacturing apparatus 1.

[0056] In the semiconductor manufacturing apparatus 22, a cylinder 23 extending in the vertical direction and pusher pins 24 housed in the cylinder 23 are arranged to pass through through-holes that penetrate the stage 4 in the vertical direction. A plurality of pusher pins 24 and cylinders 23, for example, four or more, are arranged. A temperature sensor 25 such as a thermocouple is provided inside each pusher pin 24. When a wafer 3 is supported by the multiple pusher pins 24, the multiple temperature sensors 25 come into contact with the backside of the wafer 3. A buffer material 26, such as a member containing a spring or compressed air, is enclosed on the bottom side inside the cylinder 23. When a wafer 3 is supported by the multiple pusher pins 24, the buffer material 26 bends due to the weight of the wafer 3, improving contact between the wafer 3 and each temperature sensor 25.

[0057] Cylinder 23, which houses pusher pins 24 and buffer material 26 inside, is connected to support mechanism 27, which is connected to drive shaft 28. Drive shaft 28 is connected to drive mechanism 9, which is provided below the processing chamber. By having drive mechanism 9 raise and lower drive shaft 28 in the vertical direction, the height of pusher pins 24 can be adjusted, thereby controlling the distance between the backside of wafer 3 supported by pusher pins 24 and the upper surface of stage 4.

[0058] A wafer heater 29 that uses electromagnetic waves, such as an infrared lamp, is installed on the ceiling side of semiconductor manufacturing equipment 22. In this embodiment, wafer heater 29 includes a plurality of lamps. More specifically, wafer heater 29 includes a configuration in which a plurality of annular, i.e., ring-shaped, infrared lamps 30 are arranged concentrically.

[0059] Temperature signals detected by the temperature sensors 25 and corresponding to each position on the backside of the wafer 3 are transmitted to the control circuit 19 via the PLC circuit 31. Based on the received temperature signals, the control circuit 19 independently adjusts the output of each of the infrared lamps 30 to bring the temperature of the wafer 3 closer to a set target temperature. This adjustment may be performed by so-called feedback control. The infrared lamps 30 are each disposed at a position corresponding to each position on the surface of the wafer 3 where temperature measurement is performed. The control circuit 19 identifies the temperature distribution on the surface of the wafer 3 from the received temperature signals, and independently controls the output of each infrared lamp 30 based on the identified temperature distribution, thereby adjusting the temperature distribution on the surface of the wafer 3.

[0060] <Process flow in semiconductor manufacturing apparatus according to the second embodiment> Next, the process flow in the semiconductor manufacturing equipment 22 having the above configuration will be described.

[0061] FIG. 12 is a flowchart showing an example of the flow of operations in the semiconductor manufacturing apparatus 22 according to the second embodiment.

[0062] Steps S101 to S105 and S106 to S107 in the flowchart according to the second embodiment shown in Fig. 12 are similar to steps S101 to S107 in the flowchart according to the first embodiment shown in Fig. 9. The semiconductor manufacturing apparatus 22 according to the second embodiment is characterized by the processing in steps S109 to S110.

[0063] In step S109, the wafer temperature distribution is monitored by measuring the temperature of the wafer's back surface. Specifically, while the wafer 3 is being heated by the wafer heater 29, the control circuit 19 receives temperature information from the temperature sensor 25 provided in the pusher pin 24 that contacts the back surface of the wafer 3 via the PLC circuit 31. The control circuit 19 measures and monitors the temperature distribution within the surface of the wafer 3 based on the received temperature information.

[0064] In step S110, the control circuit 19 independently controls the output of each of the multiple infrared lamps 30 based on the monitored information on the temperature distribution within the surface of the wafer 3 so that the temperature of the wafer 3 approaches the set target temperature, i.e., so that the wafer 3 has the desired temperature distribution.

[0065] According to the second embodiment, it is possible to determine in advance the height of the pusher pins 24 and the output of the wafer heater 29 so as to shorten the time required to reach the target temperature. In addition, it is also possible to control the temperature distribution on the wafer surface during heating. Therefore, in addition to the effects of the first embodiment, it is possible to improve the uniformity of the temperature distribution within the wafer surface and correct the processing dimensions at any location within the surface, thereby improving the productivity of semiconductor manufacturing.

[0066] (Third embodiment) The semiconductor manufacturing apparatus according to the third embodiment has a similar configuration to that according to the second embodiment. However, the wafer heater according to the third embodiment may be similar to the wafer heater 11 according to the first embodiment. In the semiconductor manufacturing apparatus according to the third embodiment, the output of the wafer heater 29 is kept constant and the height of the pusher pins 24 is rapidly controlled to control the temperature of the wafer 3.

[0067] 13 is a graph schematically showing the relationship between the change in pusher pin height over time and the change in wafer temperature over time according to the third embodiment. As shown in FIG. 13, as the height of the pusher pins 24 increases, the distance between the wafer 3 and the wafer heater 29 decreases, increasing the heating effect from the wafer heater 29, and the distance between the wafer 3 and the stage 4 increases, decreasing the cooling effect from the stage 4, resulting in a rise in the temperature of the wafer 3. On the other hand, as the height of the pusher pins 24 decreases, the distance between the wafer 3 and the wafer heater 29 increases, decreasing the heating effect from the wafer heater 29, and the distance between the wafer 3 and the stage 4 decreases, increasing the cooling effect from the stage 4, resulting in a drop in the temperature of the wafer 3.

[0068] By employing a drive mechanism 9 that can drive the drive shaft 28 at high speed, it is possible to quickly control the height of the pusher pins 24. By adjusting the temperature of the wafer 3 by controlling the height of the pusher pins 24 at high speed while keeping the output of the wafer heater 29 constant, it is possible to control the temperature of the wafer 3 more quickly than by adjusting the temperature of the wafer 3 by controlling the output of the wafer heater 29.

[0069] According to the third embodiment, the wafer 3 can be heated and cooled at high speed, which further reduces the processing time and improves the throughput of semiconductor manufacturing.

[0070] Although various embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and includes various modifications. Furthermore, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. All of these fall within the scope of the present invention. Furthermore, numerical values ​​and the like included in the text and figures are merely examples, and the use of different values ​​does not impair the effects of the present invention. [Explanation of symbols]

[0071] 1...semiconductor manufacturing equipment, 2...processing chamber, 3...wafer, 4...stage, 5...support member, 6...flow path, 7...pusher pin, 8...drive shaft, 9...drive mechanism, 10...top plate, 11...wafer heater, 12...opening, 13...gas supply source, 14...mass flow controller, 15...opening, 16...variable valve, 17...dry pump, 18...fluid temperature adjustment circuit, 19...control circuit, 20...memory circuit, 21...input / output circuit, 22...semiconductor manufacturing equipment, 23...cylinder, 24...pusher pin, 25...temperature sensor, 26...buffer material, 27...support mechanism, 30...infrared lamp, 31...PLC circuit

Claims

1. a processing chamber; a heater disposed outside the processing chamber and configured to heat the wafer inside the processing chamber by electromagnetic waves; a stage disposed within the processing chamber and positioned below the wafer; a wafer support mechanism that is at least partially disposed inside the processing chamber, supports the wafer, and is configured to be able to move up and down, and that is able to adjust the distance between the wafer and the stage; a gas supply / exhaust system capable of adjusting the gas pressure inside the processing chamber; a memory circuit that stores relationship information indicating the relationship between the output of the heater, the type of gas, the gas pressure inside the processing chamber, the target temperature of the wafer, the distance between the wafer and the stage, and the time required for the temperature of the wafer to reach the target temperature; a control circuit that uses the relationship information based on the set type of gas, the pressure of the gas, and the target temperature of the wafer to determine the distance between the wafer and the stage such that the time required for the temperature of the wafer to reach the set target temperature is equal to or less than a set time, and controls the wafer support mechanism so that the distance between the wafer and the stage becomes the determined distance. Semiconductor manufacturing equipment.

2. 2. The semiconductor manufacturing apparatus according to claim 1, The wafer support mechanism includes: a plurality of pusher pins for supporting the wafer; a plurality of temperature sensors, at least one of which is disposed on each of the plurality of pusher pins; the control circuit controls the output of the heater based on the backside temperature of the wafer measured by the plurality of temperature sensors so that the temperature of the wafer approaches the set target temperature. Semiconductor manufacturing equipment.

3. 3. The semiconductor manufacturing apparatus according to claim 2, the heater includes a plurality of lamps; the control circuit independently controls the output of each of the plurality of lamps based on the temperature distribution on the backside of the wafer measured by the plurality of temperature sensors. Semiconductor manufacturing equipment.

4. 4. The semiconductor manufacturing apparatus according to claim 3, The plurality of lamps each have an annular shape and are arranged concentrically. Semiconductor manufacturing equipment.

5. 2. The semiconductor manufacturing apparatus according to claim 1, the stage is connected to a temperature adjustment system that can adjust the temperature of the stage; the control circuit controls the temperature adjustment system so that the stage maintains a set temperature. Semiconductor manufacturing equipment.

6. 2. The semiconductor manufacturing apparatus according to claim 1, The wafer support mechanism includes: a plurality of pusher pins for supporting the wafer; a plurality of temperature sensors, at least one of which is disposed on each of the plurality of pusher pins; the control circuit controls the height of the pusher pins of the wafer support mechanism based on the backside temperature of the wafer measured by the plurality of temperature sensors so that the temperature of the wafer approaches the set target temperature. Semiconductor manufacturing equipment.

7. 2. The semiconductor manufacturing apparatus according to claim 1, The set gas pressure is 10 Pa or more and atmospheric pressure or less. Semiconductor manufacturing equipment.

8. a step in which a wafer support mechanism disposed inside the processing chamber and configured to be able to rise and fall supports the wafer above the stage; a gas supply and exhaust system adjusting the gas pressure within the processing chamber; a step in which a memory circuit stores relationship information representing the relationship between the output of a heater for a wafer using electromagnetic waves, the type of the gas, the pressure of the gas inside the processing chamber, the target temperature of the wafer, the distance between the wafer and the stage, and the time required for the temperature of the wafer to reach the target temperature; a step in which a control circuit determines a distance between the wafer and the stage using the relationship information based on the set type of gas, the pressure of the gas, and the target temperature of the wafer, such that the time required for the temperature of the wafer to reach the set target temperature is equal to or less than a set time; and a step of controlling the wafer support mechanism by the control circuit so that the distance between the wafer and the stage becomes the determined distance. Wafer temperature control method.

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