System for processing wafer at low temperature

Abstract

The present invention relates to a low-temperature wafer processing system. A system according to one embodiment of the present invention is a system that performs surface treatment on a wafer having a semiconductor device implemented thereon through a laser scan, and comprises: a chuck on which the wafer is placed; a temperature sensor provided on the chuck to measure the temperature of the wafer; a cooling unit provided inside the chuck or provided to contact the chuck to perform a cooling action on the wafer; a chamber which is a space in which the laser scan is performed; and a control unit that controls the cooling unit so that the laser scan is performed in a low-temperature state in which the temperature of the wafer has a temperature in the range of 25℃ to -100℃ using a temperature sensor value detected by the temperature sensor.

Description

Technology Field

[0001] The present invention relates to a technology for performing processing, such as surface treatment, on a wafer. Background Technology

[0003] Recently, in microfabrication processes for semiconductors and displays, laser systems are used to perform processing treatments such as annealing by irradiating a wafer on which semiconductor devices are formed with a laser. In this case, laser-based processing can provide a low thermal budget, high dopant activation, and super-abrupt junctions by irradiating a laser beam onto the semiconductor devices on the wafer.

[0004] This laser-based processing is performed with the wafer mounted on a chuck inside the chamber. In particular, during annealing, a laser is irradiated onto the wafer while it is fixed to the chuck to facilitate the diffusion and activation of dopants.

[0005] Meanwhile, wafers have recently been trending toward becoming thinner and more miniaturized, and accordingly, it is necessary to reduce the diffusion of dopants during laser-based processing. Of course, reducing the laser power during annealing can reduce the diffusion of dopants, but this can also affect the activation of dopants.

[0006] In particular, in conventional cases, since laser-based processing is performed at high temperatures following laser irradiation, it is impossible to control dopant diffusion while maintaining dopant activation. In other words, regarding laser-based processing of wafers, there is a need for technology that controls dopant diffusion while maintaining dopant activation, but such technology is currently non-existent.

[0007] However, the above description merely provides background information regarding the present invention and does not constitute previously disclosed technology. The problem to be solved

[0009] In order to solve the problems described above, the present invention aims to provide a technology for performing processing treatments, such as laser-based annealing, on a wafer while maintaining the wafer on which a semiconductor device is formed in a low-temperature state.

[0010] In other words, the purpose of the present invention is to provide a technology that controls the diffusion of a dopant while maintaining the activation of the dopant during laser-based processing of a wafer on which a semiconductor device is formed.

[0011] However, the problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0013] A system according to an embodiment of the present invention for solving the above-mentioned problems is a system for performing surface treatment on a wafer having a semiconductor device implemented thereon through a laser scan, and comprises: a chuck on which the wafer is placed; a temperature sensor provided on the chuck to measure the temperature of the wafer; a cooling unit provided inside the chuck or provided to contact the chuck to perform a cooling action on the wafer; a chamber which is a space in which the laser scan is performed; and a control unit that controls the cooling unit so that the laser scan is performed in a low-temperature state in which the temperature of the wafer has a temperature in the range of 25℃ to -100℃ using a temperature sensor value detected by the temperature sensor.

[0014] The temperature sensor may be positioned closer to the upper part of the chuck than the cooling part.

[0015] The above cooling unit may include a thermoelectric cooling element that performs the cooling action using the Peltier effect.

[0016] The above thermoelectric cooling element may each include a cooling portion where the cooling action occurs and a heating portion where the heating action occurs.

[0017] The above cooling portion may be provided at a relatively upper position, and the above heating portion may be provided at a relatively lower position.

[0018] The above cooling unit may further include a coolant plate that performs additional cooling action on the heat generation part by means of a coolant circulation structure.

[0019] The above coolant plate may be located at the bottom of the above heat generation part.

[0020] The above cooling unit may include a coolant plate that performs the cooling action by means of a coolant circulation structure.

[0021] A system according to one embodiment of the present invention may further include a first humidity sensor for detecting humidity inside the chamber and a first control unit for controlling humidity inside the chamber according to the value of the first humidity sensor, in order to remove moisture inside the chamber generated by the cooling action.

[0022] The first control unit above can operate to inject dry air or nitrogen gas into the interior of the chamber, or to maintain the interior of the chamber in a vacuum state.

[0023] A system according to one embodiment of the present invention may further include, in relation to a room in which a configuration for laser scanning, a chuck, a temperature sensor, a cooling unit, a chamber, a control unit, a first humidity sensor, and a first control unit are each provided inside, a second humidity sensor for detecting humidity inside the room and a second control unit for controlling humidity inside the room according to the value of the second humidity sensor in order to remove moisture inside the room.

[0024] The second control unit above can operate to inject dry air or nitrogen gas into the interior of the room.

[0025] The control unit can control the laser scan to be performed on the current target area of ​​the wafer when the current temperature sensor value detected by the temperature sensor is in the low temperature state.

[0026] The control unit can control the laser scan for the current target area to enter a standby state when the current temperature sensor value detected by the temperature sensor is higher than the low temperature state temperature.

[0027] The above control unit can control the cooling unit so that the cooling action becomes more active than before in the above standby state.

[0028] Multiple temperature sensors can be spaced apart from each other.

[0029] The control unit can determine the temperature of the current target area of ​​the wafer using the current temperature sensor values ​​detected by each temperature sensor, and if the determined temperature of the current target area is in the low temperature state, control the laser scan to be performed on the current target area.

[0030] The control unit can determine the temperature of the current target area by using the separation distance between each temperature sensor and the current target area and the current temperature sensor value detected by each temperature sensor. Effects of the invention

[0032] The present invention, configured as described above, allows for the control of dopant diffusion while maintaining the activation of the dopant on the wafer during the laser-based processing by maintaining the wafer on which the semiconductor device is formed in a low-temperature state and performing processing such as laser-based annealing on the wafer.

[0033] The effects obtainable from the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description below. Brief explanation of the drawing

[0035] FIG. 1 shows a schematic diagram of a system (1) according to one embodiment of the present invention. Figures 2 and 3 show various examples of the cooling unit (500). FIG. 4 shows a schematic diagram of a case in which additional configurations of a system (1) according to one embodiment of the present invention are further included. FIG. 5 shows a schematic flowchart of a control method according to one embodiment of the present invention. Figure 6 shows an example of scanning each line of a wafer (W) with a laser (L). Specific details for implementing the invention

[0036] Hereinafter, specific embodiments according to embodiments of the present disclosure will be described with reference to the drawings. The following detailed description is provided to facilitate a comprehensive understanding of the methods, apparatuses, and / or systems described herein. However, this is merely illustrative and the present invention is not limited thereto.

[0037] In describing the embodiments of the present disclosure, detailed descriptions of known technologies related to the present invention are omitted if it is determined that such detailed descriptions would unnecessarily obscure the essence of the embodiments. Furthermore, terms used below are defined with consideration of their functions in the present invention, and these may vary depending on the intentions or practices of the user or operator. Therefore, such definitions should be based on the content throughout this specification. Terms used in the detailed description are intended merely to describe specific embodiments and should not be limiting. Unless explicitly stated otherwise, expressions in the singular form include the meaning of the plural form. In this description, expressions such as "include" or "comprise" are intended to refer to certain characteristics, numbers, steps, actions, elements, parts thereof, or combinations thereof, and should not be interpreted to exclude the existence or possibility of one or more other characteristics, numbers, steps, actions, elements, parts thereof, or combinations thereof other than those described. Additionally, terms such as "...part," "...unit," "module," and "block" described in the specification refer to a unit that processes at least one function or operation, and this may be implemented in hardware, software, or a combination of hardware and software.

[0038] FIG. 1 shows a schematic diagram of a system (1) according to one embodiment of the present invention.

[0039] A system (1) according to one embodiment of the present invention (hereinafter referred to as “the present system”) is a system that processes a wafer (W) on which a semiconductor device (i.e., a semiconductor integrated circuit, etc.) is implemented using a laser (L). The present system (1) may be a system that performs processing such as surface treatment by irradiating each semiconductor device with a laser through scanning of the laser (L) at least one line at a time on the wafer (W).

[0040] For example, surface treatment may include optical annealing that can increase the doping concentration of a semiconductor device through laser scanning, polarity conversion of the semiconductor device surface, etc., but is not limited thereto, and may include all treatments that change the state, properties, etc. of the semiconductor device.

[0041] A wafer (W) is a silicon substrate for manufacturing semiconductor chips, on which numerous integrated circuits are formed during the semiconductor chip manufacturing process. Before each semiconductor chip is separated from the wafer (W) and mounted and assembled, processing such as surface treatment of the wafer (W) can be performed through the present system (1).

[0042] In particular, the present system (1) can perform laser (L)-based processing on the wafer (W) while maintaining the wafer (W) in a low-temperature state, thereby controlling the diffusion of the dopant while maintaining the activation of the dopant on the wafer (W) during the processing. To this end, the present system (1) may include a laser light source (100), an optical system (200), a chuck (300), a temperature sensor (400), a cooling unit (500), a chamber (600), and a control unit (700), as shown in FIG. 1.

[0043] The laser light source unit (100) is configured to generate and output a laser (L) and may include one or multiple units. For example, the laser light source unit (100) may generate a DPSS (Diode-pumped solid-state) laser, a flash LPSS (lamp-pumped solid-state) laser, etc., but is not limited thereto. Additionally, the laser light source unit (100) may generate lasers having various repetition rates (e.g., several Hz to tens of kHz) and various energies per pulse.

[0044] The optical system (200) is configured to change the optical path or modify the beam shape of the laser (L) output from the laser light source (100) and finally deliver it to the wafer (W), and includes one or more optical components. For example, such optical components may include a homogenizer, a lens, a mask, etc., but are not limited thereto.

[0045] The chuck (300) is configured to allow the wafer (W) to be placed thereon for laser (L)-based processing of the wafer (W). That is, the wafer (W) is placed on the upper part of the chuck (300) so that laser (L)-based processing of the wafer (W) can be performed. A temperature sensor (400) and a cooling unit (500) may be connected to the chuck (300). For example, the temperature sensor (400) and the cooling unit (500) may be provided to be located inside the chuck (300) or to be in contact with the chuck (300).

[0046] A temperature sensor (400) is a sensor that measures the temperature of a wafer (W). A sensor signal regarding the temperature sensor value detected by this temperature sensor (400) can be transmitted to a control unit (700). A plurality of these temperature sensors (400) may be spaced apart in the planar direction of the chuck (300). That is, if the optical axis, which is the direction in which the laser (L) is irradiated, is the z-axis direction, then the direction consisting of the x-axis and y-axis perpendicular to this z-axis corresponds to the planar direction. That is, the upper surface of the chuck (300) has a surface in this planar direction, and the wafer (W) is placed along the planar direction. At this time, a plurality of temperature sensors (400) may each be spaced apart at equal intervals in the planar direction.

[0047] In particular, the temperature sensor (400) is positioned adjacent to the upper part of the chuck (300) so that it can detect the temperature of the wafer (W) placed on the upper part of the chuck (300). That is, it may be preferable for the temperature sensor (400) to be positioned closer to the upper part of the chuck (300) than the cooling unit (500). This is to measure the temperature of the wafer (W) more accurately through the temperature sensor (400).

[0048] Figures 2 and 3 show various examples of the cooling unit (500).

[0049] Meanwhile, in the case of conventional technology, during laser-based processing of a wafer, the temperature of the chuck is maintained at a temperature within the range of 200°C to 500°C (i.e., a high-temperature state), and when the wafer is placed on the chuck, the temperature becomes the same as that of the chuck, after which laser irradiation is performed to proceed with annealing. Consequently, since laser-based processing is performed in such a high-temperature state in conventional technology, it is impossible to control diffusion in the wafer.

[0050] To solve the problems of the conventional technology, the present system (1) utilizes a cooling unit (500). This cooling unit (500) is configured to be in contact with the inside of the chuck (300) or the chuck (300) and to perform a cooling action (i.e., a heat exchange action) for the chuck (300) and the wafer (W) mounted on the chuck (300). That is, when laser (L)-based processing is performed on the wafer (W), unlike the conventional technology, the cooling unit (500) performs a cooling action for the chuck (300) and the wafer (W) mounted on the chuck (300) so that the wafer (W) can be processed in a low-temperature state. At this time, the low-temperature state may be a state having a temperature in the range of room temperature (i.e., 25°C) to -100°C.

[0051] That is, the present system (1) can perform a laser (L)-based processing process in a low-temperature state so that the activation of the dopant on the wafer (W) is maintained and the diffusion phenomenon of the dopant is appropriately controlled. The cooling action of the cooling unit (500) can be performed under the control of the control unit (700). For example, referring to FIGS. 2 and 3, the cooling unit (500) may include a thermoelectric cooling element (510) and / or a coolant plate (520).

[0052] At this time, the thermoelectric cooling element (or referred to as the “thermoelectric element”) (510) is a device that performs a cooling action using the Peltier effect (i.e., the thermoelectric effect). That is, the thermoelectric cooling element (510) can perform a cooling action on the chuck (300) and the wafer (W) placed on the chuck (300) according to the thermoelectric effect.

[0053] This thermoelectric cooling element (510) transfers heat from one side to the other while consuming electrical energy according to the direction of the current due to the thermoelectric effect. That is, the thermoelectric cooling element (510) simultaneously generates cooling and heating effects due to the thermoelectric effect. At this time, the part of the thermoelectric cooling element (510) where the cooling effect occurs is referred to as the “cooling part.” Additionally, the part of the thermoelectric cooling element (510) where the heating effect occurs is referred to as the “heating part.”

[0054] In particular, for effective cooling of the chuck (300) and the wafer (W) mounted on the chuck (300), it is preferable that the cooling portion of the thermoelectric cooling element (510) be positioned in a direction toward the wafer (W) (i.e., upward direction) (i.e., a relatively upper position closer to the wafer (W)), and the heating portion of the thermoelectric cooling element (510) be positioned in a direction toward the bottom (i.e., a relatively lower position further away from the wafer (W). Accordingly, the thermoelectric cooling element (510) can cool the chuck (300) and the wafer (W) while performing heat exchange with the chuck (300) and the wafer (W) through the cooling portion.

[0055] However, additional cooling action is required for the heat generated by the heat-generating portion of the thermoelectric cooling element (510). Accordingly, to perform the additional cooling action, a coolant plate (520) may be further provided. This coolant plate (520) may be positioned below the heat-generating portion of the thermoelectric cooling element (510) and configured to come into contact with the heat-generating portion.

[0056] At this time, the coolant plate (520) includes internal piping through which a coolant supplied via a coolant circulation device (not shown) can circulate, and as the coolant circulates, it can perform an additional cooling action. That is, the coolant plate (520) may include internal piping through which the coolant circulates, an inlet pipe through which the coolant is supplied to the piping, and an outlet pipe through which the coolant is discharged from the piping.

[0057] This coolant plate (520) is connected to a coolant circulation device. Accordingly, a coolant is supplied from the coolant circulation device to the inlet pipe of the coolant plate (520), and the supplied coolant can perform additional cooling action as it passes through the internal piping of the coolant plate (520). Of course, the used coolant that has performed additional cooling action is discharged through the outlet pipe of the coolant plate (520) and returned to the coolant circulation device. That is, the coolant plate (520) can cool the heat-generating part of the thermoelectric cooling element (510) by performing heat exchange with the supplied coolant.

[0058] Meanwhile, referring to FIG. 3, in the present system (1), only a coolant plate (520) may be provided without a thermoelectric cooling element (510). In this case, the additional cooling action described above is not required, but the coolant plate (520) can perform the cooling action for the chuck (300) and the wafer (W) mounted on the chuck (300) in place of the thermoelectric cooling element (510) according to the circulation of the coolant. That is, the coolant plate (520) can cool the chuck (300) and the wafer (W) while performing heat exchange with the chuck (300) and the wafer (W) by the supplied coolant.

[0059] The coolant supplied to the coolant plate (520) may be various fluid refrigerants, such as liquid or gas. For example, the coolant may be cooling water or liquid nitrogen, but is not limited thereto.

[0060] The chamber (600) is an internal space where laser (L)-based processing of the wafer (W) takes place. That is, processing such as surface treatment of the wafer (W) can be performed within the chamber (600). That is, the interior of the chamber (600) may be equipped with a chuck (300), a temperature sensor (400), and a cooling unit (500). The upper part of the chamber (600) may be equipped with a window (610) through which the laser (L), which is incident via the laser light source (100) and the optical system (200), passes for processing the wafer (W). For example, the window (610) may be made of a transparent material that allows the laser (L) to pass through, but is not limited thereto.

[0061] The control unit (700) controls the operation of the system (1). That is, the control unit (700) can control the laser (L)-based processing of the wafer (W) to be performed. For example, the control unit (700) can control the operation of the laser light source unit (100) and the cooling unit (500), etc.

[0062] In particular, when the control unit (700) receives a sensor signal of a temperature sensor value detected by the temperature sensor (400), it can control the cooling action of the cooling unit (500) using the temperature sensor value corresponding to the received sensor signal. Accordingly, the control unit (700) can control the wafer (W) so that it can be processed in a low temperature state (i.e., 25°C to -100°C) during laser (L)-based processing of the wafer (W). As a result, the diffusion of the dopant can be controlled while maintaining the activation of the dopant on the wafer (W) during the processing.

[0063] This control unit (700) may include a processor (not shown) and a memory (not shown). That is, the processor can control the operation of the system (1) (i.e., laser (L)-based processing, etc.) using a program stored in the memory.

[0064] For example, a processor may include, but is not limited to, a microprocessor, a central processing unit (CPU), a processor core, a multiprocessor, an application-specific integrated circuit (ASIC), or a field programmable gate array (FPGA).

[0065] For example, memory (340) may include volatile memory devices such as DRAM or SRAM, non-volatile memory such as PRAM, MRAM, ReRAM or NAND flash memory, or hard disk drive (HDD) or solid state drive (SSD), but is not limited thereto.

[0066] FIG. 4 shows a schematic diagram of a case in which additional configurations of a system (1) according to one embodiment of the present invention are further included.

[0067] Meanwhile, moisture may be generated inside the chamber (600) due to the cooling action of the cooling unit (500). This generation of moisture may affect the laser (L)-based processing process, and in particular, may also affect the wafer (W) that is the subject of the processing. Accordingly, it may be desirable to include additional components in the system (1) for processing the moisture (i.e., processing to remove moisture or reduce humidity).

[0068] In particular, moisture occurs when the temperature of the wafer (W) drops below the dew point due to the cooling action of the cooling unit (500). Accordingly, additional configurations may correspond to configurations for maintaining the temperature of the dew point lower than the temperature of the wafer (W). In order to lower the dew point temperature in this way, dry air or nitrogen gas, etc., must be injected into the chamber (600), or the inside of the chamber (600) must be maintained in a vacuum state. To this end, a first humidity sensor (810) and / or a first control unit (820) may be provided.

[0069] That is, the first humidity sensor (810) is a sensor that detects humidity inside the chamber (600). The sensor signal for the first humidity sensor value detected by this humidity sensor (810) can be transmitted to the first control unit (820) or the control unit (700).

[0070] The first control unit (820) is configured to control the humidity inside the chamber (600). At this time, the first control unit (820) may be a first method of injecting dry air or nitrogen gas, etc., so that the internal space of the chamber (600) is maintained within a preset first humidity range, or a second method of maintaining the interior of the chamber (600) in a vacuum state.

[0071] When configured in the first manner, the first control unit (820) can maintain the humidity of the internal space of the chamber (600) at a preset first humidity range by injecting dry air or nitrogen gas, etc., into the interior of the chamber (600) according to the first humidity sensor value detected by the first humidity sensor (810).

[0072] When configured in the second manner, the first control unit (820) can maintain the humidity of the internal space of the chamber (600) at a preset first humidity range by discharging air inside the chamber (600) according to the first humidity sensor value detected by the first humidity sensor (810) and creating a vacuum inside the chamber (600).

[0073] The first control unit (820) may receive the first humidity sensor value detected by the first humidity sensor (810) and operate to control the humidity inside the chamber (600) on its own. Alternatively, the first humidity sensor value detected by the first humidity sensor (810) may be transmitted to the control unit (700), and the first control unit (820) may receive a control signal from the control unit (700) and operate to control the humidity inside the chamber (600) according to the control signal.

[0074] Meanwhile, a second humidity sensor (840) and a second control unit (830), which are components for controlling humidity in a room (830) space equipped with the system (1), may be additionally provided.

[0075] That is, the second humidity sensor (840) is a sensor that detects humidity inside the room (830). The sensor signal for the second humidity sensor value detected by this humidity sensor (810) can be transmitted to the second control unit (850) or the control unit (700).

[0076] The second control unit (850) is configured to control humidity outside the chamber (600). At this time, the second control unit (850) can inject dry air or nitrogen gas, etc., so that the internal space of the room (830) maintains a preset second humidity range. That is, the second control unit (850) can maintain the humidity of the internal space of the room (830) (i.e., outside the chamber (600)) within a preset second humidity range by injecting dry air or nitrogen gas, etc., into the interior of the room (830) according to the second humidity sensor value detected by the second humidity sensor (840).

[0077] At this time, the second control unit (850) may receive the second humidity sensor value detected by the second humidity sensor (840) and operate to control the humidity inside the room (830) on its own. Alternatively, the second humidity sensor value detected by the second humidity sensor (840) may be transmitted to the control unit (700), and the second control unit (850) may receive a control signal from the control unit (700) and operate to control the humidity inside the room (830) according to the control signal.

[0078] That is, by additionally controlling the humidity inside the room (830) in addition to controlling the humidity inside the chamber (600), humidity generation can be handled more effectively.

[0079] Hereinafter, a control method according to one embodiment of the present invention will be described.

[0080] FIG. 5 shows a schematic flowchart of a control method according to one embodiment of the present invention, and FIG. 6 shows an example of scanning each line of a wafer (W) with a laser (L).

[0081] A control method according to one embodiment of the present invention (hereinafter referred to as the “present method”) is a method for performing a laser (L)-based processing treatment on a wafer (W) in a low-temperature state. According to this method, the processing treatment can be performed so that the diffusion phenomenon of the dopant is appropriately controlled while maintaining the activation of the dopant on the wafer (W).

[0082] The present method may be performed under the control of a control unit (700), etc. Referring to FIG. 5, the present method may include S510 to S520. That is, S510 and S520 may be performed by the processor of the control unit (700) processing a program stored in the memory of the control unit (700).

[0083] The control unit (700) controls the laser (L) to be irradiated onto the surface of the wafer (W) so that a laser (L)-based processing is performed. Referring to FIG. 8, the wafer (W) can be processed by scanning the laser (L) line by line on the wafer (W). At this time, after scanning the laser (L) for one area, scanning the laser (L) for the next area can be performed.

[0084] At this time, the wafer (W) may include multiple regions, each region corresponding to an area where a laser (L) scans along different lines on the wafer (W). Accordingly, a laser (L) scan of region i is referred to as the i-scan. That is, according to the laser (L)-based processing, the i-scan, i+1-scan, i+2-scan, ..., etc., can be performed sequentially. For each of these scans, a chuck (300), etc., may be provided on a stage (not shown) within the chamber (600). That is, each of the above-described scans can be performed by irradiating the wafer (W) with the movement of the stage. Of course, the control unit (700) can control the operation for each of these scans.

[0085] However, before each of these scans is performed, the control unit (700) receives a sensor signal of the current temperature sensor value detected by the temperature sensor (400) and identifies the current temperature sensor value (S510).

[0086] Afterwards, the control unit (700) uses the identified current temperature sensor value to determine whether to scan the area of ​​the wafer (W) that is currently targeted for scanning (i.e., the current target area) with the laser (L) (i.e., whether to irradiate the laser (L)) and controls the scan to be performed (S520).

[0087] That is, if the current temperature sensor value identified according to S510 is within the temperature range corresponding to a preset low temperature state, the control unit (700) controls the laser (L) to perform a scan on the current target area. For example, if the current target area is area i, before the i scan, the control unit (700) identifies the current temperature sensor value, and if the identified current temperature sensor value is within the temperature range corresponding to a low temperature state, it can control the laser (L) to perform a scan on the i area.

[0088] On the other hand, if the current temperature sensor value identified according to S510 deviates from a preset low temperature state (i.e., is at a temperature greater than the corresponding temperature range), the control unit (700) controls the laser (L) to remain in a standby state without scanning the current target area.

[0089] At this time, the control unit (700) can control the cooling action of the cooling unit (500) to become more active (i.e., more active than before). That is, the control unit (700) can control the application of more current to the thermoelectric cooling element (510) or control the circulation of the coolant in the coolant plate (520) to become more active. When such a more active cooling action is performed for a predetermined period of time, the current temperature sensor value identified according to S510 is subsequently within the temperature range corresponding to the preset low temperature state. In this case, the control unit (700) controls the scanning of the laser (L) to be performed on the current target area that was in a standby state.

[0090] In particular, with respect to S510, the control unit (700) can determine the temperature of the current target area using the current temperature sensor value detected by the temperature sensor (400). At this time, a plurality of temperature sensors (400) may be spaced apart from each other on the chuck (300), and the current temperature sensor value for each of these temperature sensors (400) may be transmitted to the control unit (700).

[0091] At this time, the control unit (700) can determine the temperature of the current target area using the current temperature sensor values ​​for the plurality of temperature sensors (400). At this time, the control unit (700) can determine the temperature of the current target area using the separation distance between each temperature sensor (400) and the current target area and the current temperature sensor value for each of the plurality of temperature sensors (400).

[0092] For example, the closer the distance between a specific temperature sensor (400) and the current target area, the closer the temperature of the current target area may be to the current temperature sensor value of the specific temperature sensor (400) (i.e., a value with a small difference). Conversely, the farther the distance between a specific temperature sensor (400) and the current target area, the further the temperature of the current target area may be from the current temperature sensor value of the specific temperature sensor (400) (i.e., a value with a large difference).

[0093] Accordingly, in S520, if the current temperature of the current target area identified as described above is within a temperature range corresponding to a preset low temperature state, the control unit (700) controls the scanning of the laser (L) for the current target area. For example, if the current target area is area i, prior to the i scan, the control unit (700) identifies the current temperature of area i based on the current temperature sensor values ​​of a plurality of temperature sensors (400), and if the identified current temperature of area i is within a temperature range corresponding to a low temperature state, the control unit (700) can control the scanning of the laser (L) for area i.

[0094] On the other hand, if the current temperature of the current target area identified as described above deviates from a preset low temperature state (i.e., is at a temperature greater than the corresponding temperature range), the control unit (700) controls the laser (L) to remain in a standby state without performing a scan of the laser (L) on the current target area. Subsequently, the control unit (700) controls the cooling action of the cooling unit (500) to be further activated, and once the temperature condition is satisfied, controls the laser (L) to perform a scan of the current target area that was in a standby state.

[0095] Of course, during the execution of the present method, the operation of the additional configuration described above (i.e., moisture removal operation) may continue to be performed in the present system (1). The present method may be executed by loading it into the memory of the control unit (700) and executing a program under the control of the processor of the control unit (700). Such a program may be stored in the memory of various types of non-transitory computer-readable media. Non-transitory computer-readable media include various types of tangible storage media.

[0096] For example, non-transient computer-readable media include, but are not limited to, magnetic recording media (e.g., flexible disk, magnetic tape, hard disk drive), magneto-optical recording media (e.g., magneto-optical disk), CD-ROM (read only memory), CD-R, CD-R / W, semiconductor memory (e.g., mask ROM, PROM (programmable ROM), EPROM (erasable PROM), flash ROM, and RAM (random access memory).

[0097] Additionally, the program may be supplied by various types of transitory computer-readable media. For example, transitory computer-readable media may include, but are not limited to, electrical signals, optical signals, and electromagnetic waves. That is, the transitory computer-readable media may supply the program to the control unit (700) through a wired communication channel, such as a wire or optical fiber, or a wireless communication channel.

[0098] The present invention, configured as described above, maintains a wafer (W) on which a semiconductor device is formed in a low-temperature state and performs a processing treatment such as laser (L)-based annealing on the wafer (W), thereby enabling the dopant's diffusion to be controlled while maintaining the dopant's activation on the wafer (W) during the laser (L)-based processing treatment.

[0100] Although the present invention has been described in detail above through representative embodiments, those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom. Accordingly, the true technical scope of protection of the present invention should be determined by the technical spirit of the appended claims. Explanation of the symbols

[0102] 1: System 100: Laser light source 200: Optical system 300: Chuck 400: Temperature sensor 500: Cooling unit 510: Thermoelectric cooling element 520: Coolant plate 600: Chamber 610: Windows 700: Chamber 810: 1st humidity sensor 820: 1st control unit 830: Room 840: Second humidity sensor 850: Second control unit

Claims

Claim 1 A system for performing surface treatment on a wafer having a semiconductor device implemented thereon through laser scanning, comprising: a chuck on which the wafer is placed; a temperature sensor provided on the chuck to measure the temperature of the wafer; a cooling unit provided inside the chuck or provided to contact the chuck to perform a cooling action on the wafer; a chamber which is a space in which the laser scanning is performed; and a control unit that controls the cooling unit so that the laser scanning is performed in a low-temperature state in which the temperature of the wafer has a temperature in the range of 25℃ to -100℃ using a temperature sensor value detected by the temperature sensor. Claim 2 In claim 1, the temperature sensor is located closer to the upper part of the chuck than the cooling part. Claim 3 In claim 1, the cooling unit comprises a thermoelectric cooling element that performs the cooling action using the Peltier effect. Claim 4 A system according to paragraph 3 in which the thermoelectric cooling element comprises a cooling portion in which the cooling action occurs and a heating portion in which the heating action occurs, wherein the cooling portion is provided at a relatively upper position and the heating portion is provided at a relatively lower position. Claim 5 In paragraph 4, the system further comprises a cooling plate that performs additional cooling action on the heat-generating part by means of a cooling plate circulation structure. Claim 6 In paragraph 5, the system wherein the coolant plate is located below the heat generation portion. Claim 7 In claim 1, the cooling unit comprises a system including a cooling plate that performs the cooling action by means of a cooling agent circulation structure. Claim 8 A system according to claim 1, further comprising a first humidity sensor for detecting humidity inside the chamber and a first control unit for controlling humidity inside the chamber according to the value of the first humidity sensor, in order to remove moisture inside the chamber generated by the cooling action. Claim 9 In claim 8, the first control unit is a system that operates to inject dry air or nitrogen gas into the interior of the chamber or to maintain the interior of the chamber in a vacuum state. Claim 10 In claim 8, in relation to a room in which the configuration for the laser scan, the chuck, the temperature sensor, the cooling unit, the chamber, the control unit, the first humidity sensor, and the first control unit are each provided inside, a system further comprising a second humidity sensor for detecting humidity inside the room and a second control unit for controlling humidity inside the room according to the value of the second humidity sensor in order to remove moisture inside the room. Claim 11 In item 10, the above-mentioned second control unit is a system that operates to inject dry air or nitrogen gas into the interior of the room. Claim 12 In claim 1, the control unit controls the laser scan to be performed on the current target area of ​​the wafer when the current temperature sensor value detected by the temperature sensor is in the low temperature state. Claim 13 In claim 12, the control unit controls the laser scan for the current target area to be in a standby state when the current temperature sensor value detected by the temperature sensor is higher than the low temperature state temperature. Claim 14 In paragraph 13, the control unit is a system that controls the cooling unit so that the cooling action becomes more active than before in the standby state. Claim 15 A system according to claim 1, wherein a plurality of temperature sensors are spaced apart from each other, and the control unit determines the temperature of the current target area of ​​the wafer using the current temperature sensor values ​​detected by each temperature sensor, and if the determined temperature of the current target area is in the low temperature state, controls the laser scan to be performed on the current target area. Claim 16 In claim 15, the control unit is a system for determining the temperature of the current target area by using the separation distance between each temperature sensor and the current target area and the current temperature sensor value detected by each temperature sensor.

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