Analytical device and analytical method

Abstract

Provided are an analysis device and an analysis method by which more minute defects on the surface of a semiconductor substrate can be analyzed. The analysis device comprises: a surface defect measurement unit that measures the presence or absence of defects on the surface of a semiconductor substrate and obtains position information regarding the position on the surface of the semiconductor substrate of a defect on the surface of the semiconductor substrate; and an analysis unit which, on the basis of the position information regarding the position of the defect on the surface of the semiconductor substrate, irradiates laser light onto the defect on the surface of the semiconductor substrate, collects, with a carrier gas, an analysis sample obtained through the irradiation, and subjects the result to inductively-coupled plasma mass spectrometry.

Description

[Technical Field]

[0001] The present invention relates to an analytical device and an analytical method for analyzing defects on the surface of a semiconductor substrate using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). [Background technology]

[0002] Currently, various semiconductor devices are manufactured using semiconductor substrates such as silicon substrates. If there are defects such as foreign particles on the surface of the semiconductor substrate during the manufacturing of the semiconductor device, the manufactured semiconductor device may be defective due to insufficient formation of transistor gates or broken wiring. In this way, the presence of defects such as foreign particles on the surface of the semiconductor substrate affects the yield of semiconductor devices.

[0003] Defects in semiconductor substrates can be evaluated using, for example, the method of evaluating residual metal impurities inside the silicon crystals of silicon wafers described in Patent Document 1. The method of evaluating residual metal impurities inside the silicon crystals of silicon wafers described in Patent Document 1 involves performing a heat treatment to collect the metal impurities inside the silicon crystals on the silicon wafer surface, and then performing vapor phase decomposition inductively coupled plasma mass spectrometry (VPD-ICP-MS) to measure the concentration of the metal impurities collected on the silicon wafer surface. The number of surface defects in the silicon wafer is measured using a SurfScan SP5 manufactured by KLA Corporation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-195020 [Patent Document 2] Japanese Patent Application Publication No. 2020-027920 Summary of the Invention [Problem to be solved by the invention]

[0005] The vapor phase decomposition inductively coupled plasma mass spectrometry described in the above-mentioned Patent Document 1 dissolves the silicon wafer, and therefore, it is not possible to evaluate defects in the semiconductor substrate nondestructively. Patent Document 2 discloses a method for evaluating metal contamination on a wafer as a method for non-destructively evaluating defects in a semiconductor substrate.

[0006] The method of evaluating metal contamination on wafers in Patent Document 2 describes the use of a particle counter (such as SurfScanSP5 manufactured by KLA Corporation) that uses a light scattering method to detect foreign particles by scanning the wafer surface with a laser beam and measuring the intensity of light scattered from the foreign particles, and a laser microscope (such as MAGICS manufactured by Lasertec Corporation) with a confocal optical system that detects foreign particles by detecting the difference in light reflected from the wafer surface. Patent Document 2 also describes the use of a scanning electron microscope (SEM) to observe the bright spots based on the coordinates obtained in the first step, and an energy dispersive X-ray spectroscopy (EDX) analysis based on the characteristic X-rays generated by electron beam irradiation.

[0007] As described above, when defects such as foreign particles are present on the surface of a semiconductor substrate, the defects on the surface of the semiconductor substrate have a significant impact on the occurrence of defective semiconductor devices and the reduction of yield, particularly as semiconductor devices become increasingly miniaturized and highly integrated. Therefore, it is important to measure defects on the surface of a semiconductor substrate, and among semiconductor substrate defects, measuring minute foreign particles is becoming even more important. However, when the wafer metal contamination evaluation method described in Patent Document 2 is used to analyze minute foreign particles of approximately 20 nm on the surface of a semiconductor substrate, it is highly likely that elemental analysis cannot be performed using EDX. Currently, there is a demand for a method that can analyze minute foreign particles of approximately 20 nm on the surface of a semiconductor substrate.

[0008] An object of the present invention is to provide an analysis apparatus and an analysis method that can analyze even smaller defects on the surface of a semiconductor substrate. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, one aspect of the present invention provides an analytical device that uses position information of defects on the surface of a semiconductor substrate, and has an analytical unit that irradiates laser light onto defects on the surface of the semiconductor substrate based on the position information of the defects on the surface of the semiconductor substrate, collects the analytical sample obtained by the irradiation with a carrier gas, and performs inductively coupled plasma mass spectrometry. One aspect of the present invention provides an analytical apparatus having a surface defect measuring device that measures the presence or absence of defects on the surface of a semiconductor substrate and obtains position information of the defects on the surface of the semiconductor substrate, and a mass spectrometer that irradiates laser light onto the defects on the surface of the semiconductor substrate based on the position information of the defects on the surface of the semiconductor substrate obtained by the surface defect measuring device, collects the analytical sample obtained by the irradiation with a carrier gas, and performs inductively coupled plasma mass spectrometry. The surface defect measuring device preferably has a storage unit for storing the position information. It is preferable that the surface defect measuring device has an incident section that causes incident light to be incident on the surface of the semiconductor substrate, and a light receiving section that receives radiated light emitted when the incident light is reflected or scattered by defects on the surface of the semiconductor substrate. One aspect of the present invention provides an analytical device having a surface defect measurement unit that measures the presence or absence of defects on the surface of a semiconductor substrate and obtains positional information on the surface of the semiconductor substrate for the defects on the surface of the semiconductor substrate, and an analytical unit that irradiates laser light onto the defects on the surface of the semiconductor substrate based on the positional information of the defects on the surface of the semiconductor substrate, collects the analytical sample obtained by the irradiation with a carrier gas, and performs inductively coupled plasma mass spectrometry.

[0010] The surface defect measuring unit preferably has a storage unit for storing the position information. It is preferable that the surface defect measurement unit has an incident unit that causes incident light to be incident on the surface of the semiconductor substrate, and a light receiving unit that receives emitted light when the incident light is reflected or scattered by defects on the surface of the semiconductor substrate. It is preferable that the apparatus has a container section for storing a semiconductor substrate to be measured, and that the semiconductor substrate is analyzed by the analysis section within the container section. It is preferable that the cleaning device has a cleaning gas supply part for supplying a cleaning gas into the container part, and an outlet part for discharging the cleaning gas from the container part. It is preferable to have an introduction section in which a container containing semiconductor substrates to be measured is placed, and a transport device that transports the semiconductor substrates from the introduction section to the surface defect measuring section.

[0011] One aspect of the present invention provides an analytical method using positional information of defects on the surface of a semiconductor substrate, the analytical method comprising the steps of irradiating the defects on the surface of the semiconductor substrate with laser light based on the positional information of the defects on the surface of the semiconductor substrate, recovering an analytical sample obtained by the irradiation with a carrier gas, and subjecting the recovered sample to inductively coupled plasma mass spectrometry. One aspect of the present invention provides an analytical method comprising the steps of: measuring the presence or absence of defects on a surface of a semiconductor substrate, and obtaining positional information on the surface of the semiconductor substrate for the defects; and irradiating the defects on the surface of the semiconductor substrate with laser light based on the positional information on the defects on the surface of the semiconductor substrate, recovering an analytical sample obtained by the irradiation with a carrier gas, and subjecting the collected sample to inductively coupled plasma mass spectrometry.

[0012] The carrier gas preferably has a moisture content of 0.00001 ppm by volume or more and 0.1 ppm by volume or less. The analyzing step is preferably carried out in a container that houses the semiconductor substrate to be measured, and the analyzing step preferably includes a step of cleaning the inside of the container with a cleaning gas. [Effects of the Invention]

[0013] According to the present invention, it is possible to analyze smaller defects on the surface of a semiconductor substrate. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram illustrating a first example of an analysis device according to an embodiment of the present invention. [Figure 2]FIG. 1 is a schematic diagram illustrating an example of an analysis unit of a first example of an analysis device according to an embodiment of the present invention. [Figure 3] FIG. 1 is a schematic cross-sectional view illustrating a first example of an analysis method according to an embodiment of the present invention. [Figure 4] FIG. 1 is a schematic cross-sectional view illustrating a first example of an analysis method according to an embodiment of the present invention. [Figure 5] FIG. 2 is a schematic diagram showing a second example of an analysis device according to an embodiment of the present invention. [Figure 6] FIG. 2 is a schematic diagram showing a third example of an analysis device according to an embodiment of the present invention. [Figure 7] FIG. 10 is a schematic diagram showing a modified example of the analysis unit of the analysis device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE INVENTION The analytical device and analytical method of the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings. It should be noted that the drawings described below are illustrative for explaining the present invention, and the present invention is not limited to the drawings shown below. In the following, the range of values ​​indicated by "~" includes the values ​​written on both sides. For example, when ε is the value ε a ~number ε b That is, the range of ε is the number ε a and the number ε b The range includes ε a ≦ε≦ε b is. Unless otherwise specified, angles such as "angles expressed by specific numerical values," "parallel," "perpendicular," and "orthogonal" include a generally acceptable error range in the relevant technical field. Furthermore, the term "same" includes a generally acceptable margin of error in the relevant technical field. Furthermore, terms such as "over the entire surface" include a generally acceptable margin of error in the relevant technical field.

[0016] [First example of analytical equipment] FIG. 1 is a schematic diagram showing a first example of an analytical device according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing an example of an analytical unit of the first example of the analytical device according to an embodiment of the present invention. 1 includes a surface defect measurement unit 20, which will be described in detail later, and an analysis unit 30. The analysis unit 10 measures a semiconductor substrate 50 as a measurement object, measures the presence or absence of defects on a surface 50a of the semiconductor substrate 50, and analyzes the defects on the surface 50a of the semiconductor substrate 50. The analysis device 10 has a first transfer chamber 12a, a measurement chamber 12b, a second transfer chamber 12c, and an analysis chamber 12d, which are arranged in succession in the following order: first transfer chamber 12a, measurement chamber 12b, second transfer chamber 12c, and analysis chamber 12d. The first transfer chamber 12a, measurement chamber 12b, second transfer chamber 12c, and analysis chamber 12d are each partitioned by walls 12h, and are provided with doors (not shown) or the like to allow the semiconductor substrate 50 to be measured to move, and the doors may be opened when the semiconductor substrate 50 is to pass through.

[0017] In the analysis apparatus 10, the semiconductor substrate 50 is transferred from the outside of the analysis apparatus 10 to the first transfer chamber 12a, and then transferred from the first transfer chamber 12a to the measurement chamber 12b, where surface defects of the semiconductor substrate 50 are measured. Next, the semiconductor substrate 50 whose surface defects have been measured is transferred from the measurement chamber 12b to the second transfer chamber 12c, and further to the analysis chamber 12d, where the analysis unit 30 analyzes the surface defects of the semiconductor substrate 50 based on the measurement results of the surface defect measurement unit 20 for the presence or absence of defects on the surface 50a of the semiconductor substrate 50. In the analysis apparatus 10, the first transfer chamber 12a, the measurement chamber 12b, the second transfer chamber 12c, and the analysis chamber 12d can be set to a specific atmosphere to prevent the semiconductor substrate 50 from being exposed to the outside air. For example, a vacuum pump may be provided to evacuate the gas inside the first transfer chamber 12a, the measurement chamber 12b, the second transfer chamber 12c, and the analysis chamber 12d to create a reduced-pressure atmosphere. Alternatively, an inert gas such as nitrogen gas may be supplied to the first transfer chamber 12a, the measurement chamber 12b, the second transfer chamber 12c, and the analysis chamber 12d to create an inert gas atmosphere inside.

[0018] As described above, the first transfer chamber 12a transfers the semiconductor substrate 50 transferred from outside the analysis device 10 to the measurement chamber 12b. An introduction section 12g is provided on the side of the first transfer chamber 12a. The storage container 13 is placed in the introduction section 12g. A sealing member (not shown) is provided in the introduction section 12g to maintain airtightness with the storage container 13. For example, a plurality of semiconductor substrates 50 are arranged like shelves and stored inside the storage container 13. The semiconductor substrates 50 are, for example, disk-shaped substrates. The storage container 13 is, for example, a FOUP (Front Opening Unified Pod). By using the storage container 13, the semiconductor substrate 50 can be transported to the analysis device 10 in a sealed state without being exposed to the outside air. This makes it possible to prevent contamination of the semiconductor substrate 50.

[0019] The first transfer chamber 12a is provided therein with a transfer device 14. The transfer device 14 transfers the semiconductor substrate 50 in the storage container 13 from the first transfer chamber 12a to the adjacent measurement chamber 12b. The transfer device 14 is not particularly limited as long as it can take out the semiconductor substrate 50 from the storage container 13 and transfer it to the stage 22 in the measurement chamber 12b. 1 includes a transfer arm 15 that holds the outside of a semiconductor substrate 50, and a drive unit (not shown) that drives the transfer arm 15. The transfer arm 15 is attached to a mounting unit 14a and is rotatable about a rotation axis C1. Note that the configuration of the transfer arm 15 is not particularly limited to one that holds the outside of the semiconductor substrate 50, as long as it can hold and transport the semiconductor substrate 50, and any arm used for transporting semiconductor wafers between processes can be used as appropriate. In the transfer device 14, the mounting portion 14a can move in a height direction V, and the transfer arm 15 can move in the height direction V, which is a direction parallel to the rotation axis C1. By moving the mounting portion 14a in the height direction V, the position of the transfer arm 15 in the height direction V can be changed.

[0020] (Surface Defect Measurement Department) As described above, surface defects of the semiconductor substrate 50 are measured in the measurement chamber 12b. A surface defect measurement unit 20 is provided inside the measurement chamber 12b. The surface defect measuring unit 20 measures the presence or absence of defects on the surface 50a of the semiconductor substrate 50, and obtains position information on the surface 50a of the semiconductor substrate 50 for the defects on the surface 50a of the semiconductor substrate 50. The surface defect measurement unit 20 has a stage 22 on which the semiconductor substrate 50 is placed, an incident unit 23 that causes incident light Ls to be incident on the surface 50a of the semiconductor substrate 50, and a focusing lens 24 that focuses the incident light Ls on the surface 50a of the semiconductor substrate 50. The stage 22 on which the semiconductor substrate 50 is placed is rotatable about a rotation axis C2, and the position of the semiconductor substrate 50 in the height direction V and in the direction H perpendicular to the height direction V can be changed. The stage 22 can change the irradiation position of the incident light Ls on the surface 50a of the semiconductor substrate 50. This allows the incident light Ls to be sequentially irradiated onto specific regions or the entire surface of the surface 50a of the semiconductor substrate 50, making it possible to detect defects such as foreign matter on the surface 50a of the semiconductor substrate 50.

[0021] The wavelength of the incident light Ls emitted by the incident portion 23 is not particularly limited. The incident light Ls is, for example, ultraviolet light, but may be visible light or other light. Here, ultraviolet light refers to light in a wavelength range of less than 400 nm, and visible light refers to light in a wavelength range of 400 to 800 nm. The angle of incidence of the incident light Ls is defined as 0° in all directions parallel to the surface 50a of the semiconductor substrate 50, and as 90° in a direction perpendicular to the surface 50a of the semiconductor substrate 50. In this case, if the angle of incidence of the incident light Ls is defined as a minimum of 0° and a maximum of 90°, the angle of incidence of the incident light Ls is equal to or greater than 0° and equal to or less than 90°, and is preferably greater than 0° and less than 90°.

[0022] The surface defect measuring unit 20 has a light receiving unit that receives radiated light emitted when the incident light Ls is reflected or scattered on the surface 50a of the semiconductor substrate 50. The surface defect measuring unit 20 shown in FIG. 1 has, for example, two light receiving units 25 and 26. If radiated light is received by either of the light receiving units 25 and 26, it is determined that there is a defect on the surface 50a of the semiconductor substrate 50, and if no radiated light is received, it is determined that there is no defect on the surface 50a of the semiconductor substrate 50. In this way, the presence or absence of defects on the surface 50a of the semiconductor substrate 50 is measured. The light receiving unit 25 is disposed around the semiconductor substrate 50. The light receiving unit 26 is disposed above the surface 50a of the semiconductor substrate 50. A condenser lens 27 is provided between the surface 50a of the semiconductor substrate 50 and the light receiving unit 26. The condenser lens 27 condenses the radiated light generated by the incident light Ls onto the light receiving unit 26. The condenser lens 27 can efficiently condense the radiated light onto the light receiving unit 26. The number of light receiving units is not particularly limited to two. The surface defect measuring unit 20 may be configured with either the light receiving unit 25 or the light receiving unit 26, or may be configured with three or more light receiving units. The light receiving section 25 receives the emitted light at a low angle. Receiving light at a low angle means receiving light at an incident angle in the range of 0° to 80°. The light receiving section 26 receives the emitted light at a high angle. Receiving light at a high angle means receiving light at an incident angle greater than 80° and equal to or less than 90°. The light receiving units 25 and 26 are configured by optical sensors such as photomultiplier tubes, for example. Furthermore, both the light receiving section 25 and the light receiving section 26 can receive either unpolarized light or polarized light.

[0023] The surface defect measuring unit 20 includes a calculation unit 28 and a storage unit 29 . The calculation unit 28 calculates the position information and size of the detected defects based on the information of the radiation received by the light receiving units 25 and 26. The position information of the defects refers to information on the position coordinates of the defects on the surface 50a of the semiconductor substrate 50. For example, the position coordinates are set using a reference position that is set in advance and common to multiple semiconductor substrates 50 as the origin.

[0024] The incident light Ls irradiated by the incident unit 23 is reflected or scattered by defects on the surface 50a of the semiconductor substrate 50, and the emitted light is received by the light-receiving units 25, 26. The light-receiving units 25, 26 detect the emitted light as a bright spot. The calculation unit 28 calculates the size of the defect that caused the bright spot, i.e., the detected size, based on the size of the standard particle from the size of the bright spot, which includes information on the emitted light from the defect. The calculation of the detected size based on the size of the standard particle is performed by a calculation unit provided in a commercially available surface inspection device or by a known calculation method. The calculation unit 28 obtains position information of the irradiation position of the incident light Ls from the control unit 42, and, for example, the light-receiving units 25, 26 obtain position information and size information of the defect on the surface 50a of the semiconductor substrate 50 based on the information on the emitted light from the defect. The obtained position information and size information of the defect on the surface 50a of the semiconductor substrate 50 are stored in the memory unit 29. The memory unit 29 is not particularly limited as long as it can store position information and size information of defects such as foreign matter on the surface 50a of the semiconductor substrate 50, and various storage media such as volatile memory, non-volatile memory, a hard disk, or an SSD (Solid State Drive) can be used.

[0025] Here, in the surface defect measuring unit 20, the stage 22 and the incident unit 23 are controlled by the control unit 42. The calculation unit 28 is also controlled by the control unit 42. The control unit 42 acquires position information on the surface 50a of the semiconductor substrate 50 of the incident light Ls irradiated by the incident unit 23. The control unit 42 drives the stage 22 to change the irradiation position on the surface 50a of the semiconductor substrate 50 so that the incident light Ls is irradiated onto an area on the surface 50a of the semiconductor substrate 50 that is not irradiated with the incident light Ls. The surface defect measuring unit 20 irradiates the entire area of ​​the surface 50a of the semiconductor substrate 50 with incident light Ls, and obtains position information and size information of defects on the surface 50a of the semiconductor substrate 50 at each irradiation position based on information on the emitted light received by, for example, the two light receiving units 25 and 26. This makes it possible to obtain position information and size information of defects over the entire surface 50a of the semiconductor substrate 50. In other words, two-dimensional position information of defects on the surface 50a of the semiconductor substrate 50 and size information of the defects can be obtained. During measurement by the surface defect measuring unit 20, the atmosphere in the measurement chamber 12b is not particularly limited, and may be a reduced pressure atmosphere as described above or a nitrogen gas atmosphere. As the surface defect measuring unit 20, for example, a surface inspection device (SurfScanSP5; manufactured by KLA Corporation) can be used.

[0026] The second transfer chamber 12c is provided therein with a transfer device 16. The transfer device 16 transfers the semiconductor substrate 50, whose surface defects have been measured by the surface defect measuring unit 20 in the measurement chamber 12b, from the measurement chamber 12b to the analysis chamber 12d. The transfer device 16 may have the same configuration as the transfer device 14 described above. The transfer device 16 has a transfer arm 15 that holds the outside of the semiconductor substrate 50, and a drive unit (not shown) that drives the transfer arm 15. The transfer arm 15 is attached to an attachment unit 16a and is rotatable around a rotation axis C1. The transfer device 16 has a mounting portion 16a that can move in a height direction V, which is a direction parallel to the rotation axis C1. The transfer arm 15 can change its position in the height direction V by moving the mounting portion 16a, to which the transfer arm 15 is attached, in the height direction V.

[0027] (Analysis Department) The analysis chamber 12d is provided therein with an analysis unit 30. The analysis unit 30 performs analysis using a laser ablation-inductively coupled plasma mass spectrometer (LA-ICP-MS). ICP-MS (Inductively Coupled Plasma Mass Spectrometer) uses argon gas plasma at approximately 10,000°C generated by inductive coupling to ionize elements in a liquid sample and perform mass analysis. LA-ICP-MS irradiates defects 51 on the surface 50a of a semiconductor substrate 50 with laser light in a laser ablation section (LA section), and introduces the analytical sample obtained by irradiation into an ICP-MS section (inductively coupled plasma mass spectrometry section) using a carrier gas to perform quantitative analysis of the elements contained in the analytical sample.

[0028] The analysis section 30 has a stage 32 on which a semiconductor substrate 50 is placed, and a container section 33 that contains the semiconductor substrate 50 placed on the stage 32. An analysis unit 36 ​​is connected to the container part 33 via piping 39. The semiconductor substrate 50 is analyzed while being entirely housed in the container part 33. The stage 32 on which the semiconductor substrate 50 is placed is rotatable about a rotation axis C3, and the position of the semiconductor substrate 50 in the height direction V can be changed, and the position in a direction H perpendicular to the height direction V can also be changed. The stage 32 is controlled by a control unit 42. The control unit 42 drives the stage 32 to change the irradiation position on the surface 50a of the semiconductor substrate 50 in order to irradiate the defect 51 on the surface 50a of the semiconductor substrate 50 with the laser light La.

[0029] The analysis unit 30 has a light source unit 34 that irradiates laser light La onto defects 51 on the surface 50a of the semiconductor substrate 50 measured by the surface defect measurement unit 20. A condenser lens 35 that condenses the laser light La onto the defects 51 on the surface 50a of the semiconductor substrate 50 is provided between the light source unit 34 and the surface 50a of the semiconductor substrate 50. The light source unit 34 and the condenser lens 35 are provided outside the container unit 33. The container unit 33 is provided with a window unit (not shown) through which the laser light La can pass so that the laser light La can pass into the inside. A femtosecond laser, a nanosecond laser, a picosecond laser, an attosecond laser, or the like is used as the light source unit 34. As the femtosecond laser, for example, a Ti:Sapphire laser can be used.

[0030] The analysis section 30 has a carrier gas supply section 38 that supplies a carrier gas into the container section 33 . The carrier gas supply unit 38 has a gas supply source (not shown), such as a cylinder, in which the carrier gas is stored, a regulator (pressure regulator) connected to the gas supply source, and an adjustment valve (not shown) that controls the amount of carrier gas supplied. For example, the regulator and the adjustment valve are connected by a tube, and the adjustment valve and the container unit 33 are connected by a pipe. The carrier gas used is, for example, helium gas or argon gas. The analysis unit 30 also has a cleaning gas supply unit 40 that supplies cleaning gas into the container unit 33. The cleaning gas supply unit 40 has a gas supply source (not shown) such as a cylinder in which cleaning gas is stored, a regulator (pressure regulator) connected to the gas supply source, and an adjustment valve (not shown) that controls the amount of cleaning gas supplied. For example, the regulator and the adjustment valve are connected by a tube, and the adjustment valve and the container unit 33 are connected by a pipe. The cleaning gas used is, for example, helium gas or argon gas.

[0031] The container 33 is also provided with an outlet 41 that allows the cleaning gas to flow out of the container 33. The outlet 41 is made up of, for example, a pipe and a valve. By opening the valve, the cleaning gas can be allowed to flow out of the container 33. The container 33 may be provided with a heater (not shown) for performing a flushing process. By heating the inside of the container 33 with the heater while a cleaning gas is supplied into the container 33, foreign matter such as ablated deposits or adsorbed gases, etc., inside the container 33 can be removed. This increases the cleanliness inside the container 33 and suppresses contamination of the semiconductor substrate 50. The heater may be, for example, an infrared lamp or a xenon flash lamp. In addition to the cleaning gas, a carrier gas can also be used in the flushing process.

[0032] <Analysis Unit> Analysis unit 36 ​​utilizes the above-mentioned ICP-MS, irradiating defects 51 on surface 50a of semiconductor substrate 50 with laser light La, collecting the analytical sample obtained by the irradiation with a carrier gas, and performing inductively coupled plasma mass spectrometry. ICP stands for inductively coupled plasma, and analysis unit 36 ​​ionizes the measurement target using high-temperature plasma maintained by high-frequency electromagnetic induction, and detects the ions with a mass spectrometer to measure the atomic species and the concentrations of the detected atomic species. The analysis unit 36 ​​includes, for example, as shown in FIG. 2, a plasma torch 44 that generates plasma to ionize the analysis sample introduced together with the carrier gas from the piping 39, and a mass analysis section 46 that has an ion introduction section located near the tip of the plasma torch 44.

[0033] The plasma torch 44 has, for example, a triple-pipe structure, and a carrier gas is introduced from a pipe 39. A plasma gas for generating plasma is also introduced into the plasma torch 44. For example, argon gas is used as the plasma gas. The plasma torch 44 is provided with a high-frequency coil (not shown) connected to a high-frequency power supply (not shown), and by applying a high-frequency current of, for example, 27.12 MHz or 40.68 MHz, approximately 1 to 2 kW to this high-frequency coil, plasma is formed inside the plasma torch 44.

[0034] In the mass spectrometer section 46, ions generated in the plasma torch 44 are introduced into an ion lens section 46a and a mass spectrometer section 46b via an ion introduction section. The ion lens section 46a and the mass spectrometer section 46b are depressurized by a vacuum pump (not shown) so that the ion lens section 46a on the plasma torch 44 side is at a low vacuum and the mass spectrometer section 46b is at a high vacuum.

[0035] The ion lens section 46a is provided with a plurality of, for example, three, ion lenses 47. The ion lenses 47 separate ions into the mass spectrometer section 46b. In the ion lens section 46a of the mass analysis section 46, the light and ions of the plasma are separated by an ion lens 47, and only the ions are allowed to pass through.

[0036] The mass spectrometer unit 46b separates ions according to their mass-to-charge ratio and detects them with a detector 49. The mass spectrometer unit 46b has a reflectron 48 and a detector 49 that detects ions that have passed through the ion lens unit 46a. The reflectron 48, also known as an ion mirror, is a device that reverses the direction of flight of charged particles using an electrostatic field. By using the reflectron 48, charged particles with the same mass-to-charge ratio but different kinetic energies can be focused on the time axis and arrive at the detector 49 at approximately the same time. The reflectron 48 compensates for errors and improves mass resolution. The reflectron 48 can be a known one used in a time-of-flight mass spectrometer (TOF-MS).

[0037] The detector 49 is not particularly limited as long as it can detect ions and identify elements, and any known detector used in a time-of-flight mass spectrometer (TOF-MS) can be used. For example, the signal (not shown) of the detected element ion can be displayed as a chart (not shown) over time by the analysis unit 36. The concentration of the detected element corresponds to the signal intensity.

[0038] 1, the analysis device 10 has a control unit 42, and the control unit 42 drives the stage 32 of the analysis unit 30 or changes the irradiation position of the laser light La based on position information and size information of the defects, such as foreign matter, detected on the surface 50a of the semiconductor substrate 50 as described above, which is stored in the memory unit 29 of the surface defect measurement unit 20, to irradiate the laser light La onto the defects 51 on the surface 50a of the semiconductor substrate 50. In this way, the defects 51 on the surface 50a of the semiconductor substrate 50 are analyzed. Furthermore, the analysis device 10 is configured so that the analysis section 30 can perform inductively coupled plasma mass spectrometry while the entire semiconductor substrate 50 is housed in the container section 33, thereby making it possible to prevent contamination of the surface 50a of the semiconductor substrate 50.

[0039] In the analyzer 10, the carrier gas and the cleaning gas are supplied through separate systems, but this is not limiting, and since the carrier gas and the cleaning gas have different supply timings, they may be supplied through a single shared arrangement to the container unit 33. For example, a configuration may be adopted in which only the carrier gas supply unit 38 is provided, without providing the cleaning gas supply unit 40. The carrier gas preferably has a moisture content of 0.00001 ppm by volume or more and 0.1 ppm by volume or less.

[0040] If the moisture content of the carrier gas is 0.00001 ppm by volume or more and 0.1 ppm by volume or less, it is possible to reduce contamination of the surface 50a of the semiconductor substrate 50 during analysis in the container part 33. For example, if the moisture content of the carrier gas is high, impurities may dissolve in trace amounts of moisture adhering to the surface of the carrier gas piping or the inner surface of the container part 33, and these may re-adhere to the semiconductor substrate 50, increasing the number of defects; however, if the moisture content of the carrier gas is within the above-mentioned range, this is suppressed. Furthermore, if the moisture content is low, the surface 50a of the semiconductor substrate 50 is likely to become charged when the carrier gas passes near the semiconductor substrate 50. As a result, charged particles floating in the container 33 are likely to be attracted to the surface 50a of the semiconductor substrate 50, and particles floating nearby during transport in the transport system are likely to be attracted to the surface 50a of the semiconductor substrate 50. Furthermore, although redeposition of products resulting from laser ablation is likely to occur, this is suppressed if the moisture content of the carrier gas is within the above-mentioned range. The amount of moisture contained in the carrier gas can be measured using an atmospheric pressure ionization mass spectrometer (API-MS). More specifically, the amount of moisture contained in the carrier gas can be measured using, for example, an API-MS manufactured by Japan API Co., Ltd. The method for adjusting the moisture content is not particularly limited, but can be achieved by performing a gas purification process to remove water (water vapor) contained in the raw material gas. In particular, the moisture content in the carrier gas can be adjusted by adjusting the number of purification steps or the filter. The flow rate of the carrier gas is 1.69 x 10 -3 ~1.69 Pa m 3 / sec (1 to 1000 sccm (standard cubic centimeter per minute)) is desirable.

[0041] [First example of analysis method] The analytical method includes a step of measuring the presence or absence of defects on the surface of the semiconductor substrate, obtaining positional information of the defects on the surface of the semiconductor substrate, and a step of irradiating the defects on the surface of the semiconductor substrate with laser light based on the positional information of the defects on the semiconductor substrate, recovering an analytical sample obtained by the irradiation with a carrier gas, and subjecting the sample to inductively coupled plasma mass spectrometry. The analytical method will now be described in detail. FIG. 3 is a schematic diagram illustrating a first example of the analysis method according to the embodiment of the present invention, and FIG. 4 is a schematic cross-sectional view illustrating the first example of the analysis method according to the embodiment of the present invention. 3 and 4, the same components as those in the analysis device 10 shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0042] In the analysis method, for example, a storage container 13 (see FIG. 1) storing a plurality of semiconductor substrates 50 is connected to an inlet 12g on the side of a first transfer chamber 12a of the analysis device 10 shown in FIG. 1. The lid of the storage container 13 is opened to allow the semiconductor substrates 50 to be removed from the storage container 13. Next, the semiconductor substrate 50 is removed from the storage container 13 using the transfer device 14 in the first transfer chamber 12a, and the semiconductor substrate 50 is transferred to the stage 22 in the measurement chamber 12b. By the above-mentioned process of transferring the semiconductor substrate 50 from the storage container 13 to the stage 22 in the measurement chamber 12b, contamination of the semiconductor substrate 50 is suppressed even if the semiconductor substrate 50 is transferred from outside the analysis device 10. With contamination of the semiconductor substrate 50 suppressed, the surface defect measuring unit 20 can measure the surface defects of the semiconductor substrate 50.

[0043] Next, in the measurement chamber 12b, the surface defect measurement unit 20 measures the surface defects of the semiconductor substrate 50. As a result, the position information and size of defects such as foreign matter on the surface 50a of the semiconductor substrate 50 are detected. For example, as shown in FIG. 3, a defect 51 can be displayed on the surface 50a of the semiconductor substrate 50. Displaying the defect 51 on the surface 50a of the semiconductor substrate 50 is called mapping. The position information and size information of the defect 51 on the surface 50a of the semiconductor substrate 50 is stored in the memory unit 29. The position information and size information of the defect 51 on the surface 50a of the semiconductor substrate 50 is called mapping information.

[0044] Next, the semiconductor substrate 50, whose surface defects have been measured, is transported from the measurement chamber 12b to the analysis chamber 12d by the transport device 16 in the second transport chamber 12c shown in FIG. Next, in analysis chamber 12d, analysis unit 30 performs analysis based on position information and size information of defect 51 on surface 50a of semiconductor substrate 50, i.e., mapping information. As shown in Fig. 4, the analysis is performed with the entire semiconductor substrate 50 housed in container 33 and with carrier gas (not shown) supplied into container 33 from carrier gas supply unit 38. During analysis, the position of defect 51 is identified based on the mapping information, and semiconductor substrate 50 is moved, for example, using stage 32, to a position where defect 51 is irradiated with laser light La. 4, laser light La is irradiated onto defect 51 on surface 50a of semiconductor substrate 50. Analysis sample 51a obtained by irradiating defect 51 with laser light La is moved by a carrier gas (not shown) through piping 39 to analysis unit 36. Analysis sample 51a derived from defect 51 and moved by the carrier gas is subjected to inductively coupled plasma mass spectrometry in analysis unit 36, and the elements of defect 51 are identified.

[0045] The analysis method preferably includes a step of cleaning the inside of the container part 33 with a cleaning gas before the analysis step. Specifically, the cleaning step is a step of supplying a cleaning gas into the container part 33, heating the inside of the container part 33 with a heater, and performing a flushing process before transferring the semiconductor substrate 50 into the container part 33. The cleaning step removes foreign matter such as ablated deposits or adsorbed gases from inside the container part 33.

[0046] Furthermore, the analysis apparatus 10 can use position information of the defects 51 on the surface 50a of the semiconductor substrate 50, which is obtained by measuring the defects 51 on the surface 50a of the semiconductor substrate 50 using another apparatus different from the analysis apparatus 10, for example, a surface defect measuring apparatus 70 (see FIG. 1). The position information of the defects 51 on the surface 50a of the semiconductor substrate 50 is, for example, mapping information as shown in FIG. 3. In this case, the mapping information acquired by the surface defect measuring apparatus 70 is supplied to the storage unit 29. Furthermore, the semiconductor substrate 50, whose surface 50a has been measured for defects 51 by the surface defect measuring apparatus 70, is stored in, for example, a storage container 13 and transported to the analysis apparatus 10. The semiconductor substrate 50 is transported to the analysis chamber 12d via the first transport chamber 12a, the measurement chamber 12b, and the second transport chamber 13c. Next, control unit 42 reads out the mapping information from storage unit 29, and identifies the position of defect 51 on surface 50a of semiconductor substrate 50 based on the mapping information. Next, stage 32 is used to move semiconductor substrate 50 to a position where defect 51 is to be irradiated with laser light La. Next, laser light La is irradiated onto defect 51 on surface 50a of semiconductor substrate 50. Analysis sample 51a obtained by irradiating defect 51 with laser light La is moved by carrier gas to analysis unit 36. Analysis sample 51a derived from defect 51 and moved by carrier gas is subjected to inductively coupled plasma mass spectrometry in analysis unit 36, and the elements of defect 51 are identified.

[0047] As described above, when defects 51 are analyzed using mapping information such as that shown in Fig. 3 measured by surface defect measuring device 70 (see Fig. 1), there is no need to measure the surface defects of surface defect measuring unit 20 and semiconductor substrate 50. It goes without saying that analysis device 10 may be configured without surface defect measuring device 70 shown in Fig. 1. The position information of the defects 51 on the surface 50a of the semiconductor substrate 50 supplied to the storage unit 29 is not particularly limited to that measured by the surface defect measuring device 70 (see FIG. 1). The surface defect measuring device 70 may, for example, have a storage unit (not shown) that stores the position information. The surface defect measuring device 70 may also have a configuration similar to that of the surface defect measuring unit 20 (see FIG. 1). For this reason, the surface defect measuring device 70 has, for example, an incident unit 23 that makes incident light Ls incident on the surface 50a of the semiconductor substrate 50, and a light receiving unit 26 that receives radiated light that is emitted when the incident light Ls is reflected or scattered by the defects 51 on the surface 50a of the semiconductor substrate 50.

[0048] [Second example of analytical equipment] Fig. 5 is a schematic diagram showing a second example of an analytical device according to an embodiment of the present invention. In Fig. 5, the same components as those in the analytical device 10 shown in Fig. 1 are denoted by the same reference numerals, and detailed descriptions thereof will be omitted. The analytical apparatus 10a shown in Figure 5 differs from the analytical apparatus 10 shown in Figure 1 in that it does not have a second transport chamber 12c and a transport device 16, and that the surface defect measurement section 20 and the analysis section 30 are located within a single processing chamber 12e.Other than that, the configuration is the same as that of the analytical apparatus 10 shown in Figure 1.

[0049] In the analysis device 10a, the semiconductor substrate 50 is entirely housed in the container portion 33, and surface defect measurement and analysis are carried out. In the analysis section 30, the light source section 34 is disposed so that the optical axis of the laser light La is tilted with respect to the surface 50a of the semiconductor substrate 50. In the analysis device 10a, the surface defect measuring section 20 and the analysis section 30 are provided in one processing chamber 12e, so that the device can be made smaller than the analysis device 10 shown in FIG. Furthermore, by configuring the semiconductor substrate 50 so that the surface defect measurement unit 20 can measure surface defects and the analysis unit 30 can perform inductively coupled plasma mass spectrometry while the entire semiconductor substrate 50 is housed within the container unit 33, the transportation of the semiconductor substrate 50 can be reduced, further suppressing contamination of the surface 50a of the semiconductor substrate 50. This can further improve the accuracy of measuring defects on the surface 50a of the semiconductor substrate 50, and also suppress contamination inside the processing chamber 12e of the analysis device 10a.

[0050] [Second example of analysis method] The second example of the analysis method is basically the same as the first example of the analysis method described above. The second example of the analysis method differs from the first example of the analysis method described above in that the measurement of surface defects is carried out by surface defect measurement unit 20 while semiconductor substrate 50 is entirely housed in container unit 33, and that after the measurement of the surface defects, semiconductor substrate 50 whose surface defects have been measured is not transported from measurement chamber 12b (see FIG. 1) to analysis chamber 12d (see FIG. 1) by transport device 16 (see FIG. 1). Other steps are the same as those of the first example of the analysis method. In a second example of the analysis method, the entire semiconductor substrate 50 is stored in the container section 33, and surface defects are measured by the surface defect measurement section 20 and inductively coupled plasma mass spectrometry is performed by the analysis section 30, thereby further suppressing contamination of the surface 50a of the semiconductor substrate 50 and suppressing contamination within the processing chamber 12e of the analysis apparatus 10a. Furthermore, as described above, by carrying out the measurement of surface defects by the surface defect measuring unit 20 and the inductively coupled plasma mass spectrometry by the analyzing unit 30 while the entire semiconductor substrate 50 is housed in the container unit 33, it is not necessary to transport the semiconductor substrate 50 between processes, and the analysis time can be shortened compared to the first example of the analysis method. Furthermore, as described above, contamination of the surface 50a of the semiconductor substrate 50 can be further suppressed.

[0051] Furthermore, similar to the analysis apparatus 10, the analysis apparatus 10a can also use mapping information such as that shown in FIG. 3 obtained by measuring defects 51 on the surface 50a of the semiconductor substrate 50 using another apparatus different from the analysis apparatus 10a, for example, a surface defect measuring apparatus 70 (see FIG. 5). In this case, the mapping information obtained by the surface defect measuring apparatus 70 is supplied to the storage unit 29. Furthermore, the semiconductor substrate 50, whose surface 50a has been measured for defects 51, is stored in, for example, a storage container 13 and transported to the analysis apparatus 10a. In the analysis device 10a, based on the mapping information, the analysis section 30 in the processing chamber 12e performs inductively coupled plasma mass spectrometry on the analysis sample 51a derived from the defect 51 in the analysis unit 36d as described above, thereby identifying the elements of the defect 51. Even in this case, if mapping information measured by the surface defect measuring device 70 (see FIG. 5) is used, there is no need to measure the surface defects of the surface defect measuring unit 20 and the semiconductor substrate 50. Of course, the analysis device 10a may also be configured without the surface defect measuring device 70 shown in FIG. 5, similar to the analysis device 10. Furthermore, the position information of the defects 51 on the surface 50a of the semiconductor substrate 50 supplied to the memory unit 29 is not particularly limited to that measured by the surface defect measuring device 70 (see FIG. 5).

[0052] [Third example of analytical equipment] As described above, when using mapping information measured by a device other than the analyzer, for example, the surface defect measuring device 70, the analyzer does not necessarily need a surface defect measuring unit, and the analyzer may be configured without a surface defect measuring unit. In this case, the analyzer has only the analysis unit 30 (see FIG. 1). Fig. 6 is a schematic diagram showing a third example of an analytical device according to an embodiment of the present invention. In Fig. 6, the same components as those in the analytical device 10 shown in Fig. 1 and the analytical device 10a shown in Fig. 5 are designated by the same reference numerals, and detailed descriptions thereof will be omitted. 1, the analysis apparatus 10b shown in Fig. 6 does not include the first transfer chamber 12a, the transfer device 14, the measurement chamber 12b, the surface defect measuring unit 20, the second transfer chamber 12c, and the transfer device 16. The analysis apparatus 10b also includes the above-described surface defect measuring device 70 and the mass spectrometer 72, with the analysis unit 30 (see Fig. 1) being a mass spectrometer 72. Because the mass spectrometer 72 has the same configuration as the above-described analysis unit 30 (see Fig. 1), a detailed description of the mass spectrometer 72 will be omitted.

[0053] In the analysis apparatus 10b, the surface defect measuring apparatus 70 and the mass spectrometer 72 are separate apparatuses and are not integrated. In this case, the mapping information acquired by the surface defect measuring apparatus 70 is supplied to the storage unit 29. Furthermore, the semiconductor substrate 50, whose surface 50a has been measured for defects 51, is stored in, for example, a storage container 13 and transported to the mass spectrometer 72. The semiconductor substrate 50 is transported to the analysis chamber 12d via the first transport chamber 12a. Next, in the mass spectrometer 72, the control unit 42 reads out the mapping information from the memory unit 29, and based on the mapping information, the analysis sample 51a derived from the defects 51 is subjected to inductively coupled plasma mass spectrometry in the analysis unit 36d in the analysis chamber 12d as described above, thereby identifying the elements of the defects 51. Furthermore, the position information of the defects 51 on the surface 50a of the semiconductor substrate 50 supplied to the memory unit 29 can also be position information other than that measured by the surface defect measuring device 70 (see FIG. 6).

[0054] The analysis unit 30 of the above-described analysis apparatus 10 and analysis apparatus 10a, and the mass spectrometer 72 of the analysis apparatus 10b are not limited to the configuration of the above-described analysis unit 30. Here, Fig. 7 is a schematic diagram showing a modified example of the analysis unit of the analysis apparatus according to the embodiment of the present invention. In Fig. 7, the same components as those in the analysis apparatus 10 shown in Fig. 1 are designated by the same reference numerals, and detailed description thereof will be omitted. As shown in FIG. 7, the analysis section 30 may be provided with an imaging section 60 for observing the surface 50a of the semiconductor substrate 50, and a display section 62 for displaying an image obtained by the imaging section 60. The imaging unit 60 can observe the irradiation position of the laser light La on the surface 50a of the semiconductor substrate 50, i.e., the position of the defect 51. The imaging unit 60 can be a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor. The display unit 62 can be a liquid crystal monitor or an organic EL (Electro Luminescence) monitor. The light source unit 34 and the imaging unit 60 are arranged, for example, with their optical axes (not shown) perpendicular to each other. The imaging unit 60 is arranged opposite the surface 50a of the semiconductor substrate 50. A half mirror 64 is disposed at the point where the optical axis of the light source unit 34 intersects with the optical axis of the imaging unit 60. The laser light La emitted by the light source unit 34 is reflected by the half mirror 64, passes through the condenser lens 35, and is irradiated onto the surface 50a of the semiconductor substrate 50.

[0055] (semiconductor substrate) The semiconductor substrate is not particularly limited, and various types of semiconductor substrates can be used, such as a silicon (Si) substrate, a sapphire substrate, a SiC substrate, a GaP substrate, a GaAs substrate, an InP substrate, or a GaN substrate, etc. Silicon semiconductor substrates are widely used as semiconductor substrates.

[0056] The present invention is basically configured as described above. While the analytical device and analytical method of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various improvements and modifications may be made without departing from the spirit and scope of the present invention. [Example]

[0057] The present invention will be described in more detail below with reference to the following examples. The materials, amounts used, ratios, treatment details, and treatment procedures shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the following examples. Examples 1 to 29 and Comparative Examples 1 to 3 will be explained below.

[0058] Examples 1 to 20 In this example, a dispersion containing Fe nanoparticles of 10 to 20 nm was prepared. The dispersion was diluted and dispersed on a silicon substrate with a diameter of 300 mm at a density of approximately 1 particle / cm. 2 The dispersion liquid thus prepared was applied onto a silicon substrate having a diameter of 300 mm using an electrostatic spraying device. The silicon substrate coated with the dispersion liquid was placed in a container that could accommodate the entire silicon substrate, and then transported to a surface defect measurement unit. A surface inspection device (SurfScanSP5; manufactured by KLA Corporation) was used for the surface defect measurement section. In the surface inspection device, laser light was incident on the surface of the silicon substrate, and scattered light was measured to measure the position and size of defects on the silicon substrate, and information on the defect position and size was obtained and stored in a memory section. Next, the silicon substrates that had undergone surface defect measurement were transported to the analysis section. A laser ablation ICP mass spectrometry (LA-ICP-MS) device was used in the analysis section. When transporting the silicon substrates from the surface defect measurement section to the analysis section, the silicon substrates were transported in a state isolated from the outside air. When using the storage container described above, the silicon substrates were kept isolated from the outside air throughout the transport.

[0059] Based on the obtained defect location information and defect size information, elemental analysis of the laser ablation defects was performed using a laser ablation ICP mass spectrometer to confirm whether Fe could be detected at the specified laser ablation positions. Laser ablation was performed with the silicon substrate placed in the container and carrier gas supplied. The analytical sample obtained by laser ablation was collected with the carrier gas and analyzed by inductively coupled plasma mass spectrometry. A femtosecond laser was used for laser ablation. After that, the contamination status of the silicon substrate was checked again in the surface defect measurement section, i.e., whether the silicon substrate was contaminated during the analysis and whether the defects were ablated. The moisture concentration in the carrier gas is shown in Tables 1 and 2 below. Argon gas was used as the carrier gas. The flow rate of the carrier gas was 1.69 × 10 -2 Pa·m 3 / sec (10 sccm). In Examples 1 to 14, the interior of the container was cleaned by flushing using a carrier gas before performing elemental analysis of defects by laser ablation. In Examples 15 to 20, the interior of the container was not cleaned by flushing using a carrier gas.

[0060] (Examples 21 to 29) Examples 21 to 26 are the same as Example 1 except that, unlike Example 1, the silicon substrates were transported without using a storage container for storing semiconductor substrates. In Examples 21 to 26, when the silicon substrates were transported from the surface defect measurement unit to the analysis unit, the silicon substrates were transported in a state exposed to the outside air. Examples 27 to 29 are the same as Example 1 except that the silicon substrates were transported without using a storage container for storing semiconductor substrates and that the inside of the container was not cleaned using a carrier gas. In Examples 27 to 29, the silicon substrates were transported exposed to the outside air when transported from the surface defect measurement unit to the analysis unit.

[0061] A FOUP (Front Opening Unified Pod) was used as a storage container for storing semiconductor substrates. When a storage container was used, "Yes" was recorded in the column for semiconductor substrate storage container in Tables 1 and 2 below. On the other hand, when a storage container was not used, "No" was recorded in the column for semiconductor substrate storage container in Tables 1 and 2 below.

[0062] (Comparative Examples 1 to 3) In Comparative Examples 1 to 3, a surface inspection device (SurfScanSP5; manufactured by KLA Corporation) was used to irradiate a laser onto the surface of a silicon substrate and measure the scattered light to measure the position and size of defects on the silicon substrate, and information on the position and size of the defects was obtained and stored in a memory unit. Next, based on the obtained defect position information and defect size information, a defect review device (SEMVision G6 (manufactured by Applied Materials)) was used to attempt qualitative elemental analysis of the defects on the silicon substrate. The qualitative elemental analysis of the defects on the silicon substrates of Comparative Examples 1 to 3 was performed using SEM-EDS (Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy). In Comparative Examples 1 to 3, SEM-EDS was used for the qualitative elemental analysis of defects on the silicon substrate as described above. SEM-EDS is performed under vacuum using an electron beam, so no carrier gas is used. For this reason, for Comparative Examples 1 to 3, "-" is entered in the "Water content of carrier gas" column in Table 2 below. Comparative Examples 1 to 3 did not have a container part, and therefore "-" was entered in the "Container part cleaning step" column in Table 2 below.

[0063] [Table 1]

[0064] [Table 2]

[0065] As shown in Tables 1 and 2, in Examples 1 to 29, the target Fe particles were ablated in the analysis step, and Fe was detected by elemental analysis. In Examples 1 to 29, the number of defects on the silicon substrate was reduced after analysis, and the number of defects on the silicon substrate was not increased, so it was confirmed that ablation was performed. Note that the reason the number of defects on the silicon substrate after analysis was not zero is thought to be because contamination during analysis could not be reduced to zero. On the other hand, in Comparative Examples 1 to 3, a laser ablation ICP mass spectrometer was not used, and the sensitivity of the SEM-EDS elemental analysis was insufficient, so qualitative elemental analysis of defects could not be performed and Fe could not be detected.

[0066] Furthermore, it was confirmed from Examples 1 to 29 that the contamination of the surface of the silicon substrate during analysis can be reduced by controlling the impurity concentration of the carrier gas to 0.00001 ppm or more and 0.1 ppm or less. In other words, by adjusting the moisture content of the carrier gas, cleaning can be performed simultaneously with analysis. From a comparison between Examples 1 to 6 and Examples 15 to 20, it was confirmed that the inclusion of a cleaning step reduced contamination of the silicon substrate during analysis. From a comparison between Examples 1 to 20 and Examples 21 to 29, it was confirmed that when a storage container for storing semiconductor substrates was used, contamination of silicon substrates before analysis was less likely to occur. [Explanation of symbols]

[0067] 10, 10a, 10b analyzer 12a First transport room 12b Measurement room 12c Transport Room 2 12d Analysis room 12e Processing Room 12g introduction 12h wall 13 Storage container 14 Conveyor equipment 14a Mounting part 15 Transfer arm 16. Conveying equipment 16a Mounting part 20 Surface defect measurement section Stages 22 and 32 23 Incidence part 24 Condenser lens 25, 26 Light receiving section 27 Condenser Lens 28 Arithmetic section 29 Memory section 30 Analysis Department 33 Container section 34 Light source section 35 Condenser lens 36 Analysis Units 38 Carrier gas supply unit 39 Piping 40 Cleaning gas supply unit 41 Outlet 42 Control Unit 44 Plasma Torch 46 Mass spectrometry department 46a Ion lens section 46b Mass spectrometer section 47 Ion Lens 48 Reflectron 49 Detectors 50 Semiconductor substrate 50a surface 51 Defects 51a Analytical Sample 70 Surface defect measuring device 72 Mass spectrometer C1, C2, C3 rotation axes H direction La laser light Ls incident light V Height direction

Claims

1. a surface defect measuring unit that measures the presence or absence of defects on a surface of the semiconductor substrate and obtains position information on the surface of the semiconductor substrate for the defects on the surface of the semiconductor substrate; an analysis unit that irradiates the defect on the surface of the semiconductor substrate with laser light based on the position information of the defect on the surface of the semiconductor substrate, collects an analysis sample obtained by the irradiation with a carrier gas, and performs inductively coupled plasma mass spectrometry; the surface defect measuring unit is provided inside a measurement chamber and includes an incident unit that makes incident light incident on the surface of the semiconductor substrate, and a light receiving unit that receives radiated light that is radiated as a result of the incident light being reflected or scattered by the defects on the surface of the semiconductor substrate, the incident light being ultraviolet light; The analysis unit is an analysis device in which a light source unit that irradiates the defects on the surface of the semiconductor substrate with laser light is provided inside an analysis chamber.

2. The analysis device according to claim 1 , wherein the surface defect measuring unit includes a storage unit that stores the position information.

3. a container portion for storing the semiconductor substrate to be measured; The analysis device according to claim 1 , wherein the analysis unit analyzes the semiconductor substrate inside the container unit.

4. a cleaning gas supply unit that supplies a cleaning gas into the container unit; The analyzer according to claim 3 , further comprising an outlet portion for causing the cleaning gas to flow out from the container portion.

5. The analytical device according to any one of claims 1 to 4, comprising an introduction section in which a storage container containing the semiconductor substrate to be measured is placed, and a transport device that transports the semiconductor substrate from the introduction section to the surface defect measurement section.

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