Sputtering Equipment

Abstract

To provide a sputtering device and a sputtering method that can prevent abnormality of film deposition processing.SOLUTION: A sputtering device comprises: a vacuum container 11 which contains a substrate 12; a target 46 which has one surface facing the inside of the vacuum container; a gas supply part 35 which supplies a gas for generating plasma in the vacuum container; a power supply part 71 which supplies electric power to the target so as to generate the plasma and sputter the target to deposit a film on the substrate; and an abnormality detection part which detects abnormality occurring owing to a temperature of the target.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a sputtering apparatus. Place Regarding. [Background technology]

[0002] A sputtering apparatus used in the manufacturing process of semiconductor devices is configured to place a target made of a film-forming material in a vacuum chamber, form an electric field on the underside of the target to generate plasma, and sputter the target with ions from the plasma.

[0003] Patent document 1 describes that when sputtering a target, a small movable magnet is provided behind the target to move the area eroded by sputtering, thereby making it possible to avoid localized excessive heating or melting of the target. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2004-534153 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides a technique capable of preventing abnormalities in a film formation process in a sputtering apparatus. [Means for solving the problem]

[0006] The sputtering apparatus of the present disclosure includes a vacuum vessel for storing a substrate; a rotating stage provided within the vacuum chamber for horizontally placing the substrate thereon; a target electrode provided on a ceiling of the vacuum vessel at an angle to a substrate placed on the stage; and a flow passage forming member provided on the ceiling of the vacuum vessel, the flow passage forming member being provided on the ceiling of the vacuum vessel at an angle to a substrate placed on the stage. a magnet array provided on the other side of the target electrode for magnetron sputtering; a gas supply unit that supplies a gas for forming plasma in the vacuum chamber; a power supply unit that supplies power to the target in order to form the plasma and sputter the target to form a film on the substrate; an abnormality detection unit for detecting an abnormality caused by a temperature of the target; Equipped with The abnormality detection unit includes a temperature detection unit that detects a temperature of the refrigerant in a discharge path of the refrigerant that is connected to the flow path; another temperature detection unit that detects the temperature of the refrigerant in a supply path of the refrigerant connected to the flow path; a first detection mechanism that detects the presence or absence of the abnormality based on a comparison between a difference value between one detection value by the one temperature detection unit and another detection value by the other temperature detection unit and a threshold value; a moving mechanism for moving the magnet array back and forth between an upper end side and a lower end side of the target along the other surface, that is, an upper surface, of the target electrode, the abnormality detection unit includes a load detection unit for detecting a load of the movement mechanism, which is a torque of a motor included in the movement mechanism; A storage unit is provided to store the load, a second detection mechanism is provided that detects the presence or absence of the abnormality based on the loads acquired at different times and stored in the storage unit; If the substrate on which a film is formed first and the substrate on which a film is formed later in the vacuum vessel are referred to as a first substrate and a second substrate, respectively, the second detection mechanism calculates a difference value between the torque detected during film formation on the first substrate and the torque detected during film formation on the second substrate at different positions on the reciprocating path of the magnet array moved by the moving mechanism, and detects the presence or absence of the abnormality by comparing each difference value with a predetermined threshold value. Effect of the Invention

[0007] According to the present disclosure, a technique is provided that can prevent abnormalities in a film formation process in a sputtering apparatus. [Brief description of the drawings]

[0008] [Figure 1] 1 is a vertical cross-sectional view of a magnetron sputtering apparatus according to the present disclosure. [Diagram 2]FIG. 4 is a schematic diagram showing a target electrode in a normal state. [Diagram 3] FIG. 2 is a schematic diagram showing a target electrode in which peeling of the target has occurred. [Figure 4] FIG. 2 is a configuration diagram showing a control unit provided in the magnetron sputtering apparatus. [Diagram 5] 5 is a time chart illustrating detection of an abnormality based on a current detection value. [Figure 6] 5 is a time chart illustrating detection of an abnormality based on a torque detection value. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A magnetron sputtering apparatus 1, which is a sputtering apparatus according to an embodiment of the present disclosure, will be described with reference to the drawings. Fig. 1 is a vertical cross-sectional side view of the magnetron sputtering apparatus 1. In the figure, reference numeral 11 denotes a grounded vacuum vessel made of, for example, aluminum. In the figure, reference numeral 12 denotes a transfer port for a semiconductor wafer (hereinafter referred to as "wafer") 100, which is a substrate, opened in the side wall of the vacuum vessel 11, and which is opened and closed by an opening / closing mechanism 13.

[0010] A circular stage 21 serving as a mounting portion is provided within the vacuum vessel 11, on which the wafer 100 is horizontally mounted. One end of a vertically extending shaft 22 is connected to the center of the rear surface of the stage 21. The other end of the shaft 22 extends outside the vacuum vessel 11 via a bearing 14 provided at the bottom of the vacuum vessel 11, and is connected to a rotation mechanism 23. The rotation mechanism 23 configures the stage 21 to be freely rotatable about a vertical axis via the shaft 22.

[0011] A heater (not shown) is provided inside the stage 21, and the wafer 100 is heated to a predetermined temperature during the film formation process. The stage 21 is also provided with protruding pins (not shown) for transferring the wafer 100 between the stage 21 and a transfer mechanism (not shown) outside the vacuum vessel 11.

[0012] An exhaust port 31 opens at the bottom of the vacuum vessel 11. One end of an exhaust pipe 32 is connected to the exhaust port 31, and the other end of the exhaust pipe 32 is connected to an exhaust pump 33. In the figure, 34 denotes an exhaust amount adjustment mechanism interposed in the exhaust pipe 32. A gas nozzle 35, which is a gas supply unit for generating plasma, is provided on the upper side of the side wall of the vacuum vessel 11, and the gas nozzle 35 is connected to a gas supply source 36 in which an inert gas such as Ar is stored. In the figure, 37 denotes a flow rate adjustment unit consisting of a mass flow controller, which controls the amount of Ar gas supplied from the gas supply source 36 to the gas nozzle 35.

[0013] A rectangular opening 41 is formed in the ceiling of the vacuum vessel 11, and an insulating member 42 is provided along the edge of the opening 41 on the inside side of the vacuum vessel 11. A holding portion 43 is provided along the insulating member 42, and a plate-shaped target electrode 40 that is rectangular in plan view is provided on the inner peripheral side of the holding portion 43 so as to cover the opening 41. The target electrode 40 is disposed at an angle with respect to the wafer 100, and is provided so that its long side descends from the inner side to the outer side of the wafer 100.

[0014] The target electrode 40 is composed of a target 46 that is a film-forming material, a flow path forming portion 45, and an adhesive layer 47. The target 46 faces the inside of the vacuum vessel 11, and the flow path forming portion 45 faces the outside of the vacuum vessel 11, and the target 46 and the flow path forming portion 45 are bonded via the adhesive layer 47. The target 46 is composed of a material such as titanium (Ti), tungsten (W), or tantalum (Ta). The adhesive layer 47 is composed of indium, for example. The flow path forming portion 45 has a coolant flow path 60 that is formed to meander from one end side to the other end side inside, and is formed, for example, by bonding a copper thick plate in which a groove for forming the flow path 60 is formed, to block the upper side of the groove.

[0015] A cooling water supply pipe 62, which is a supply path for the above-mentioned refrigerant, specifically, cooling water, whose temperature is adjusted by a chiller 61, is connected to one end of the flow path 60. A cooling water discharge pipe 63, which is a discharge path for the refrigerant, for returning the cooling water that has flowed through the flow path 60 to the chiller 61, is connected to the other end of the flow path 60. This forms a circulation path in which the cooling water enters from one end of the flow path 60, is discharged from the other end, and returns to the chiller 61. The temperature of the cooling water is adjusted to a predetermined temperature every time it returns to the chiller 61. Furthermore, the cooling water supply pipe 62 is provided with a first temperature detection unit 64 that detects the temperature of the cooling water supplied from the chiller 61 to the flow path 60. Furthermore, the cooling water discharge pipe 63 is provided with a second temperature detection unit 65 that detects the temperature of the cooling water discharged from the flow path 60 and returned to the chiller 61. The roles of the first temperature detection unit 64 and the second temperature detection unit 65 will be described in detail later.

[0016] A power supply unit 71 is also connected to the flow path forming unit 45. The power supply unit 71 is controlled to supply a constant power to the target electrode 40, and generates an electric field within the vacuum chamber 11. A current detection unit 73, which is a parameter detection unit for detecting the value of a current supplied to the target electrode 40, is provided on a conductive path 72 connecting the power supply unit 71 and the flow path forming unit 45. The role of the current detection unit 73 will also be described in detail later. Note that in this example, a negative DC voltage is applied to the target electrode 40 by the power supply unit 71, but an AC voltage may be applied instead of the DC voltage.

[0017] Further, a magnet array 51 is provided on the rear side of the target electrode 40 as viewed from the wafer 100. The magnet array 51 includes a rectangular support plate 52 parallel to the target 46, and a plurality of magnets 53 forming a magnetic circuit. The magnets 53 extend from the lower surface of the support plate 52 in the thickness direction of the support plate 52, and their lower ends are adjacent to the flow path forming portion 45.

[0018] 1, a bracket 54 is provided on the upper part of the support plate 52 and is connected to a moving mechanism 55. The moving mechanism 55 is composed of, for example, a ball screw 56 having a screw shaft 56A extending in the length direction of the target electrode 40, and a motor 57 which is a rotation mechanism for rotating the screw shaft 56A around its axis. The ball screw 56 is screwed into the bracket 54. When the motor 57 rotates forward and backward, the magnet array 51 moves back and forth between one end side (upper end side) and the other end side (lower end side) of the target 46 along the upper surface of the target electrode 40. This controls the distribution of the amount of sputtering within the surface of the target 46, and is configured to prevent localized sputtering of the target 46.

[0019] The rotation speed of the motor 57 is changed by the amount of current supplied from a power supply unit (not shown). When the magnet array 51 repeatedly moves along the reciprocating path, the operation of the motor 57 is controlled so that the moving speed is constant at the same position along the reciprocating path. In other words, when viewed from a certain position along the reciprocating path, even if different wafers 100 are being processed or even at different times during the processing of one wafer 100, the magnet array 51 moves to that position at a constant speed. Note that, for example, the operation of the motor 57 is controlled so that the speed of the magnet array 51 at each position along the reciprocating path other than both ends where acceleration and deceleration are required is also constant. The motor 57 is connected to the ball screw 56 via a torque detector 58, which is a load detector, and the torque of the motor 57 when rotating the screw shaft 56A can be detected.

[0020] Next, the processing of the wafer 100 in the magnetron sputtering apparatus 1 will be described. First, the transfer port 12 of the vacuum vessel 11 is opened, and the wafer 100 is transferred to the stage 21 by the cooperation of an external transfer mechanism and a push-up pin (not shown). Next, the transfer port 12 is closed, and Ar gas is supplied into the vacuum vessel 11, while the exhaust amount is controlled by the exhaust amount adjustment mechanism 34, so that the inside of the vacuum vessel 11 is made into a vacuum atmosphere of a desired pressure. Cooling water is passed through the flow path 60 of the target 46, and the temperature of the target 46 is adjusted.

[0021] Then, the stage 21 rotates around the vertical axis, and the magnet array 51 moves back and forth over the target 46 by the moving mechanism 55. A negative DC voltage is applied from the power supply unit 71 to the target electrode 40, generating an electric field around the target electrode 40, and electrons accelerated by this electric field collide with the Ar gas, ionizing the Ar gas. New electrons are generated by the ionization of the Ar gas. Meanwhile, the magnet 53 forms a magnetic field along the surface of the target 46 where the magnet 53 is located.

[0022] The electrons are accelerated and drift due to the electric field and the magnetic field in the vicinity of the target 46. The electrons, which have gained sufficient energy due to the acceleration, collide with the Ar gas, causing ionization and forming plasma, and the Ar ions in the plasma sputter the target 46. Secondary electrons generated by this sputtering are captured by the horizontal magnetic field and contribute again to ionization, thus increasing the electron density and densifying the plasma.

[0023] The particles of the target 46 sputtered as described above adhere to the wafer 100, and a film is formed on the wafer 100. Then, when a predetermined time has elapsed since the power supply unit 71 was turned on, the power supply is turned off, the generation of plasma is stopped, the supply of Ar gas is stopped, and the wafer 100 is carried out of the vacuum chamber 11 in the reverse order of the process of carrying it in. Thereafter, the succeeding wafers 100 are successively carried into the magnetron sputtering apparatus 1, and the same process as that described above is carried out.

[0024] However, in such a sputtering apparatus, it is required to increase the throughput. To achieve this, it is considered to supply a relatively large amount of power to the target electrode 40, promote the ionization of the Ar ions as described above, and relatively increase the deposition rate (amount of deposition per unit time). As a specific example, when the power supplied to the target 46 / area of ​​the target 46 is 50 W / cm 2 It is being considered to supply power in such a way that the above conditions are met. However, if a material with a relatively low thermal conductivity, such as Ti, W, or Ta, is used as the constituent material of the target 46, the heat generated by the high power supply as described above tends to remain in the target 46. In other words, heat exchange between the cooling water flowing through the flow path 60 of the target 46 and the target 46 is not sufficiently performed, and the target 46 becomes relatively hot. If the temperature of the target 46 rises in this way, there is a risk that the target 46 will melt and fall onto the wafer 100, or that voids will occur in the target 46 due to a change in the particle size of the particles constituting the target 46. As a rule of thumb, it is known that if sputtering is performed in a state in which such voids have occurred, there is a high tendency for particles to be mixed into the film formed on the wafer 100.

[0025] Each of the first temperature detection unit 64, the second temperature detection unit 65, the current detection unit 73, and the torque detection unit 58 is provided to indirectly detect abnormalities (melting, changes in particle size of the constituent particles) caused by the temperature of the target 46, and to prevent abnormalities in the processing of the wafer 100. The detection of abnormalities by the first temperature detection unit 64, the second temperature detection unit 65, and the torque detection unit 58 among the above detection units utilizes the fact that the target 46 may peel off from the flow path forming unit 45 due to an increase in temperature. This peeling of the target 46 will be explained with reference to Figs. 2 and 3. Figs. 2 and 3 respectively show the target electrode 40 in a normal state where the target 46 is not peeled off, and the target electrode 40 in a state where an abnormality has occurred in which the target 46 is peeled off. When the target 46 becomes hot, a part of the adhesive layer 47 melts. Then, the part of the target 46 where the adhesive layer 47 has melted is bent by the weight of the target 46 and moves away from the flow path forming unit 45.

[0026] In the target electrode 40 in the normal state shown in Fig. 2, the entire back surface of the target 46 contacts the flow path forming portion 45 via the adhesive layer 47, and the entire back surface is cooled by the cooling water. On the other hand, in the target electrode 40 in which the target 46 has peeled off as shown in Fig. 3, the contact area between the flow path forming portion 45 and the target 46 is smaller than in the normal state due to the peeling. Therefore, the entire back surface of the target 46 cannot be cooled, the amount of heat removed from the target 46 by the cooling water is reduced, and the temperature of the cooling water flowing through the cooling water discharge pipe 63 becomes relatively low.

[0027] Therefore, the first temperature detection unit 64 detects the temperature of the cooling water before removing the heat from the target 46 in the cooling water supply pipe 62, and the second temperature detection unit 65 detects the temperature of the cooling water that has been heated by removing the heat from the target 46 in the cooling water discharge pipe 63. More specifically, a difference value between the second temperature detection value detected by the second temperature detection unit 65 and the first temperature detection value detected by the first temperature detection unit 64 is obtained. As described above, when peeling of the target 46 occurs and the amount of heat removal changes, this difference value changes accordingly. That is, peeling of the target 46 due to a high temperature can be detected based on the difference value, and when this peeling occurs, it is considered that the melting and particle size abnormality of the target 46 have also occurred, and the presence or absence of the melting and particle size abnormality can be detected. If the fluctuation in temperature of the cooling water supplied from chiller 61 to cooling water supply pipe 62 is relatively small, first temperature detection unit 64 need not be provided, and the abnormality can be detected using the detection value only from second temperature detection unit 65. In other words, first temperature detection unit 64 is provided to detect abnormalities with higher accuracy, and first temperature detection unit 64 does not need to be provided.

[0028] Next, the role of the torque detection unit 58 will be described in detail. According to Lenz's law, when a magnet is brought close to a metal, magnetic lines of force are also generated around the metal, and the magnet moves against the magnetic field caused by the magnetic lines of force. Therefore, as described above, when the target 46 peels off, the peeled part moves away from the magnet array 51 and is less susceptible to the action of the magnet 53. Therefore, when the magnet array 51 passes near the peeled part, the peeled part has little contribution to the formation of the magnetic field, and the magnetic field is formed mainly by the flow path forming unit 45, which is a copper plate. As the metal that forms the magnetic field becomes smaller (thinner), the effect of the magnetic field also becomes smaller. As described above, the magnet array 51 is controlled to pass each position on the reciprocating path at a determined speed. Therefore, when peeling of the target 46 occurs, the torque of the motor 57 when the magnet array 51 passes near the peeled portion becomes smaller than the torque obtained before the peeling occurs. Therefore, similarly to the case where the detection values ​​of the first temperature detection unit 64 and the second temperature detection unit 65 are used, the detection value of the torque detection unit 58 can be used to detect the occurrence or absence of peeling of the target 46, and further the occurrence or absence of melting and grain size abnormality of the target 46.

[0029] Next, the role of the current detection unit 73 will be described. As described above, the power supply unit 71 supplies a constant power to the target 46, and the current value supplied to the target 46 at this time is relatively high, which correlates with the occurrence of melting of the target 46. This is believed to be due to the fact that when melting of the target 46 occurs, the amount of secondary electrons (electrons emitted by sputtering of the target 46) from the target 46 increases. Therefore, the presence or absence of an abnormality in the melting of the target 46 can be detected from the detection result of the current detection unit 73.

[0030] The detection values ​​of the first temperature detection unit 64, the second temperature detection unit 65, the current detection unit 73, and the torque detection unit 58 may be output to a display unit, such as a display, and an operator may look at the display to detect the presence or absence of an abnormality caused by the temperature of the target 46. The operator may then perform tasks such as stopping the operation of the apparatus or stopping the loading of the wafer 100 as necessary, thereby preventing the processing of the wafer 100 from becoming abnormal. However, from here on, an example will be described in which detection signals corresponding to the detection values ​​of each of the first temperature detection unit 64, the second temperature detection unit 65, the current detection unit 73, and the torque detection unit 58 are output to the control unit 9 of the magnetron sputtering apparatus 1 shown in Figure 1, and the control unit 9 detects an abnormality caused by the temperature of the target 46.

[0031] 4 is a block diagram showing the control unit 9 which is a computer. The control unit 9 which is the first to third detection mechanisms includes a CPU 91, a memory 92, and a program 93. In the figure, 90 is a bus to which the CPU 91, the memory 92, a storage unit 94 which stores the program 93, the first temperature detection unit 64, the second temperature detection unit 65, the current detection unit 73, and the torque detection unit 58 are each connected. The control unit 9 sends control signals to each unit of the magnetron sputtering apparatus 1 by the program 93. The program 93 includes instructions so that each operation such as the movement of the magnet array 51, the rotation of the stage 21, the supply of Ar gas, and the on / off of the power supply unit 71 described above can be controlled by these control signals, and the film formation process of the wafer 100 can be performed. The program 93 also detects an abnormality caused by the temperature of the target 46 described above. That is, the program 93 includes first to third detection mechanisms. The program 93 is stored in the storage unit 94 in a storage medium 93A, and is installed in the control unit 9. The storage medium 93A is, for example, a compact disk, a hard disk, an MO (magneto-optical disk), a memory card, or a DVD.

[0032] The memory 92 includes a temperature data storage section 92A in which the detection values ​​by the first and second temperature detection sections 64 and 65 are stored, a current data storage section 92B in which the detection value by the current detection section 73 is stored, and a torque data storage section 92C in which the detection value by the torque detection section 58 is stored. The current data storage section 92B and the torque data storage section 92C correspond to a first storage section and a second storage section. As described later, a detection value acquired at a certain time point and a detection value acquired at another time point earlier than the detection value are used for the detection of an abnormality by the current detection section 73 and the detection of an abnormality by the torque detection section 58. Therefore, at least the current data storage section 92B and the torque data storage section 92C store a plurality of detection values ​​acquired at different times. An alarm output unit 95 is also connected to the bus 90. Depending on the result of the abnormality determination, which will be described later, a control signal is output so that the alarm output unit 95 operates. Specifically, for example, an alarm is output by voice or screen display to notify an operator that an abnormality has occurred.

[0033] An example of an abnormality detection method using each detection unit will be described below. First, an abnormality detection using the first and second temperature detection units 64 and 65 will be described. As described above, at any timing during the period during which power is supplied from the power supply unit 71 to process the wafer 100 and plasma is generated, the control unit 9 acquires detection signals output from the first temperature detection unit 64 and the second temperature detection unit 65. Then, the first temperature detection value T1 obtained from the first temperature detection unit 64 and the second temperature detection value T2 obtained from the second temperature detection unit 65 are stored in the memory 92, and the difference value (T2-T1) is calculated. When peeling of the target 46 occurs, the second temperature detection value T2 of the cooling water in the exhaust pipe becomes relatively low as described above, so the difference value (T2-T1) becomes a relatively small value. The control unit 9 compares this difference value (T2-T1) with a preset threshold value, and if it is higher than the threshold value, it is determined to be normal. If it is equal to or lower than the threshold value, it is determined to be abnormal.

[0034] Next, detection of an abnormality using the current detection unit 73 will be described. As described above, when the target 46 melts due to heat, the current supplied to the target electrode 40 increases. However, the current supplied to the target electrode 40 also tends to increase as the magnetron sputtering apparatus 1 continues to operate and the target 46 is consumed, even if no such abnormality occurs. Therefore, the increase in current caused by the melting of the target 46 is detected so as to be distinguished from the increase in current caused by the consumption of the target 46.

[0035] For ease of understanding, Fig. 5 is a graph that shows a schematic change in current over time when the current detection unit 73 detects the current every time a wafer 100 is processed in the magnetron sputtering apparatus 1. The wafers 100 are loaded into the magnetron sputtering apparatus 1 at approximately regular intervals and processed. The target 46 is gradually consumed every time a process is performed, and the detected current value increases gradually with each detection. Heat is accumulated in the target 46 as the process is repeated, and when the temperature rises, the target 46 melts. When this melting occurs, the detected current value increases rapidly.

[0036] Therefore, the control unit 9 acquires a current value, which is a parameter, by the current detection unit 73 at an arbitrary timing after the start of processing, for example, for the wafer 100 (assumed to be the first wafer 100), and stores it in the memory 92. Then, when processing a wafer 100 (assumed to be the second wafer 100) that is subsequently loaded into the device, the current detection unit 73 acquires a current value at the same timing and stores it in the memory 92. Then, the control unit 9 calculates a difference value between the current value during processing of the second wafer 100 and the current value during processing of the first wafer 100. The control unit 9 compares this difference value with a preset threshold value, and if it is smaller than the threshold value, it is determined to be normal. If it is equal to or greater than the threshold value, it is determined to be abnormal. Since the current value also changes due to consumption of the target 46 as described above, this threshold value is set to a relatively large value to match the sudden increase caused by melting of the target 46.

[0037] Note that the current value may be obtained each time the wafer 100 is processed and the difference value may be obtained as described above and compared with the threshold value, or the current value may be obtained each time processing is performed multiple times and the difference value may be compared with the threshold value. In other words, the first wafer 100 and the second wafer 100 described above may or may not be wafers 100 that are successively loaded into the device. Also, for example, the difference value between the average value of several current values ​​obtained in one period and the average value of several current values ​​obtained in another subsequent period may be calculated and compared with the threshold value. The handling of the detection values ​​obtained in this manner can be set arbitrarily.

[0038] Next, detection of an abnormality using the torque detection unit 58 will be described. As described above, peeling of the target 46 causes a decrease in the detected torque. However, even if no such abnormality occurs, the torque tends to gradually decrease as the target 46 is consumed as the magnetron sputtering apparatus 1 continues to operate and the effect of the magnetic field generated by the target 46 weakens. Therefore, the decrease in torque caused by peeling of the target 46 is detected so as to be distinguished from a change in torque caused by consumption of the target 46.

[0039] For ease of understanding, Fig. 6 is a graph that shows a schematic change in torque over time when torque detection is performed by the torque detection unit 58 every time a wafer 100 is processed in the magnetron sputtering apparatus 1. Here, too, it is assumed that the wafer 100 is loaded into the magnetron sputtering apparatus 1 at approximately regular intervals and processed. The target 46 is gradually consumed every time processing is performed, and the detected torque therefore gradually decreases with each detection. When repeated processing is performed in this manner, heat is accumulated in the target 46 and the temperature of the target 46 rises, causing the target 46 to peel off. When peeling occurs in this manner, the torque drops suddenly.

[0040] Therefore, the control unit 9 obtains a torque detection value by the torque detection unit 58 at an arbitrary timing after the start of processing, for example, for the wafer 100 (first wafer 100), and stores it in the memory 92. Then, when processing a wafer 100 (second wafer 100) subsequently loaded into the device, the control unit 9 obtains a torque detection value by the torque detection unit 58 at the same timing and stores it in the memory 92. Then, it calculates the detection value when processing the first wafer 100 minus the detection value when processing the second wafer 100. The control unit 9 compares this difference value with a preset threshold value, and if it is smaller than the threshold value, it determines that the difference is normal. If it is equal to or greater than the threshold value, it determines that there is an abnormality. Since the torque also changes due to wear of the target 46 as described above, this threshold value is set to a relatively large value to match the sudden decrease caused by peeling of the target 46. As in the detection of anomalies using current values ​​described above, the timing of acquiring torque to calculate the difference value to be compared with the threshold value is not limited to every process, and the difference between average values ​​over different periods may be compared with the threshold value. In this way, the handling of the acquired detection value for torque can be set arbitrarily. Although the example of acquiring each detection value for each wafer has been described, it is also possible to acquire the detection values ​​at different times during the processing of one wafer 100 and compare the difference value with the threshold value.

[0041] Incidentally, if peeling of the target 46 occurs, the torque when the magnet array 51 passes near the location where the peeling occurred will be lower than in normal times. However, it is considered that the torque when the magnet array 51 passes a position relatively distant from the location where the peeling occurred will not change compared to normal times. Therefore, in order to improve the accuracy of abnormality detection, the torque when the magnet array 51 passes through multiple positions on the reciprocating movement path is obtained. Then, for each obtained position, abnormality detection may be performed using the detection value during processing of the first wafer 100 and the detection value during processing of the second wafer 100, as described above.

[0042] When one or more of the detection results from the first and second temperature detection units 64, 65, the current detection unit 73, and the torque detection unit 58 are determined to be abnormal, the program 93 determines that the above-mentioned temperature-related abnormality has occurred and outputs an alarm. Note that the operation of the device may be stopped at the same time as the output of this alarm.

[0043] As described above, according to the magnetron sputtering apparatus 1, an abnormality caused by the temperature of the target 46 can be detected by using the first temperature detection unit 64, the second temperature detection unit 65, the current detection unit 73, and the torque detection unit 58, which constitute the abnormality detection unit. This makes it possible to prevent the processing performed on the wafer 100 from becoming abnormal. Note that, in the above description, the abnormality caused by the temperature of the target 46 is assumed to be melting and a change in grain size, and the presence or absence of peeling of the target 46 is detected in order to detect these. However, the present technology may also be used for the purpose of detecting peeling of the target 46 itself as a temperature-related abnormality.

[0044] Incidentally, the abnormality determination by the current detection unit 73 may be determined to be abnormal if the detection value is relatively high when detected at any timing. Similarly, the torque detected by the torque detection unit 58 may be determined to be abnormal if the measured value is relatively low when measured at any timing. In other words, the memory 92 is not limited to storing measured values ​​acquired at different timings. The method of detecting each abnormality that has been described so far as being performed by the control unit 9 may be performed by the operator by looking at the display unit as described above.

[0045] Furthermore, the magnetron sputtering apparatus is not limited to a configuration in which the magnet array 51 moves back and forth linearly. For example, the magnetron sputtering apparatus may be configured such that a rotation axis extending in a direction perpendicular to the surface direction of the target 46 is rotated by the motor 57, and the magnet array rotates about the rotation axis as the center of rotation to change the magnetic field on the front surface side (lower surface side) of the target 46. Even in this case, a torque detector may be provided to measure the torque of the motor 57 or detect the torque of the rotation axis. Furthermore, there is a correlation between the torque as the load of the motor 57 and the current supplied to the motor 57. Therefore, an abnormality may be detected by detecting the current instead of the torque.

[0046] Also, instead of providing a current detector 73 for detecting the current supplied to the target electrode 40, a voltage detector for detecting the voltage value of the voltage applied to the target electrode 40 may be provided. The target electrode 40 is controlled so that a constant power is supplied thereto, and therefore, when the current supplied to the target electrode 40 increases, the voltage decreases. Therefore, when the target 46 melts, the current increases, and the voltage decreases accordingly. Therefore, similar to the case of detecting a change in current as described in FIG. 5, it is possible to detect melting of the target 46 by detecting a change in voltage and detecting when the amount of change in voltage becomes greater than a threshold value.

[0047] Furthermore, the sputtering apparatus according to the present disclosure is not limited to a magnetron sputtering apparatus equipped with the magnet array 51. For example, a sputtering apparatus may be used that does not include the magnet array 51, generates an electric field in a vacuum chamber by applying power to a target electrode, converts an inert gas into plasma, and sputters a target with ions in the plasma. Even in this case, it is possible to detect an abnormality by the first temperature detection unit 64, the second temperature detection unit 65, and the current detection unit 73.

[0048] As discussed above, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0049] 1. Magnetron sputtering equipment 11 Vacuum container 35 Gas Nozzle 21 Stage 46 Target 58 Torque detector 64 First temperature detection unit 65 Second temperature detection unit 73 Current detection section 100 wafers

Claims

1. a vacuum vessel for storing the substrate; a rotating stage provided within the vacuum chamber for horizontally placing the substrate thereon; a target electrode provided on a ceiling of the vacuum vessel at an angle to a substrate placed on the stage; and a flow passage forming member provided on the ceiling of the vacuum vessel, the flow passage forming member being provided on the ceiling of the vacuum vessel at an angle to a substrate placed on the stage. a magnet array provided on the other side of the target electrode for magnetron sputtering; a gas supply unit that supplies a gas for forming plasma in the vacuum chamber; a power supply unit that supplies power to the target in order to form the plasma and sputter the target to form a film on the substrate; an abnormality detection unit for detecting an abnormality caused by a temperature of the target; Equipped with The abnormality detection unit includes a temperature detection unit that detects a temperature of the refrigerant in a discharge path of the refrigerant that is connected to the flow path; another temperature detection unit that detects the temperature of the refrigerant in a supply path of the refrigerant connected to the flow path; a first detection mechanism that detects the presence or absence of the abnormality based on a comparison between a difference value between one detection value by the one temperature detection unit and another detection value by the other temperature detection unit and a threshold value; a moving mechanism for moving the magnet array back and forth between an upper end side and a lower end side of the target along the other surface, that is, an upper surface, of the target electrode, the abnormality detection unit includes a load detection unit for detecting a load of the movement mechanism, which is a torque of a motor included in the movement mechanism; A storage unit is provided to store the load, a second detection mechanism is provided that detects the presence or absence of the abnormality based on the loads acquired at different times and stored in the storage unit; The substrate on which a film is formed first and the substrate on which a film is formed later in the vacuum chamber are referred to as a first substrate and a second substrate, respectively.The second detection mechanism calculates a difference value between the torque detected during film formation on the first substrate and the torque detected during film formation on the second substrate at different positions on the reciprocating path of the magnet array moved by the moving mechanism, and detects the presence or absence of the abnormality by comparing each difference value with a predetermined threshold value.

2. 2. The sputtering apparatus according to claim 1, wherein the abnormality detection unit includes a parameter detection unit that detects, as a parameter, a value of a current supplied to the target by the power supply unit or a value of a voltage applied to the target by the power supply.

3. a first storage unit that stores the parameters; 3. The sputtering apparatus according to claim 2, further comprising a third detection mechanism for detecting the presence or absence of the abnormality based on the parameters acquired at different times and stored in the first storage section.

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