Inspection equipment

Abstract

The present invention provides an inspection device that can accurately measure the thickness of a film, etc., even during long-term inspections of the inspection device. [Solution] The inspection device 10 includes a light source device 11 equipped with a light source 30 that irradiates an object to be inspected with inspection light, an imaging device 20 that receives the inspection light that has passed through the object to be inspected, and a control device 12 that controls the light source device 11 and the imaging device 20. The light source device 11 includes a light source 30, a temperature measuring instrument 32, and a temperature regulator 33 for maintaining the temperature of the light source 30 within a predetermined temperature range based on the temperature measured by the temperature measuring instrument 32. The temperature measuring instrument 32 measures the temperature of the light source 30, and the control device 12 maintains the temperature of the light source 30 within a predetermined temperature range using the temperature regulator 33. With this configuration, the wavelength of the inspection light irradiated from the light source 30 can be stabilized, and high-precision inspections can be performed for long periods of time and during the startup of the inspection device 10.

Description

Technical Field

[0001] The present invention relates to an inspection apparatus. More specifically, the present invention relates to an inspection apparatus in which a temperature regulator for the temperature of a light source is provided in a light source device.

Background Art

[0002] Patent Document 1 discloses a wafer measurement apparatus. This wafer measurement apparatus calculates the thickness of a film provided on a wafer from spectroscopic characteristic data of linear measurement light. This linear measurement light is irradiated from a light source such as an LED. FIG. 11 shows a cross-sectional view of a light source device 50 when an LED is used. This cross-sectional view is a cross-sectional view in a plane perpendicular to the linear direction of the light source 51. The light source 51 is included in the light source device 50. The light source device 50 has, in addition to the light source 51, a support member 52 that supports the light source 51. And the support member 52 has a heat sink 53 for radiating heat from the light source 51. The light source device 50 irradiates the measurement light irradiated from the light source 51 downward in the plane of FIG. 11 through an aperture 54.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when attempting to calculate the thickness of a film on a wafer using spectral characteristic data, the inspection light emitted from the LED must be highly stable. Here, the inspection light emitted from the LED has characteristics that change with the LED temperature. When the LED temperature changes, in the configuration of a conventional light source device, i.e., a configuration in which a heat sink is provided on a support member with an surrounding structure, the wavelength or intensity of the inspection light, i.e., the spectral characteristics, changes, affecting the spectral characteristic data, and thereby reducing the accuracy of the calculated film thickness. Inspection devices such as wafer measuring devices are often used for long periods of time, and in this case, the temperature of the atmosphere in which the inspection device is installed changes, which presents a problem as the film thickness cannot be measured with high accuracy. Furthermore, during the startup of inspection equipment such as wafer measuring devices, the temperature of the LED rises rapidly, significantly altering the spectral characteristics of the emitted measurement light. This creates a problem where the film thickness cannot be measured with high accuracy.

[0005] In view of the above circumstances, the present invention aims to provide an inspection device that can measure the thickness of a film with high accuracy, even during long-term inspections of the inspection device. [Means for solving the problem]

[0006] The inspection apparatus of the first invention comprises a light source device equipped with a light source that irradiates an object to be inspected with inspection light, an imaging device that receives the inspection light that has passed through the object to be inspected, and a control device that controls the light source device and the imaging device, wherein the light source device comprises the light source, a temperature measuring instrument, and a temperature regulator for maintaining the temperature of the light source within a predetermined temperature range based on the temperature measured by the temperature measuring instrument, the temperature measuring instrument measures the temperature of at least one of the light source, a support member that supports the light source, or the temperature regulator, and the control device maintains the temperature of the light source within a predetermined temperature range using the temperature regulator. The inspection apparatus of the second invention is characterized in that, in the first invention, the light source is a line light source. The inspection apparatus of the third invention is characterized in that, in the second invention, the line light source is configured such that light-emitting elements are arranged in a line. The inspection apparatus of the fourth invention is characterized in that, in the first invention, the imaging apparatus includes a two-dimensional sensor. The inspection apparatus of the fifth invention is characterized in that, in the first invention, heat is transferred by a liquid in the temperature controller. The inspection apparatus of the sixth invention is characterized in that, in the first invention, heat is transferred by gas in the temperature controller. The inspection apparatus of the seventh invention is characterized in that, in the first invention, heat transfer is performed by a solid in the temperature controller. The inspection apparatus of the eighth invention is characterized in that, in the seventh invention, the temperature controller is a Peltier element. The inspection apparatus of the ninth invention is characterized in that, in the first invention, the support member has an enclosing structure for emitting the inspection light from the light source in a predetermined direction, and the temperature controller is in contact with the light source inside the support member. The inspection apparatus of the 10th invention is characterized in that, in the first invention, the support member has an enclosing structure for emitting the inspection light from the light source in a predetermined direction, and the temperature controller is provided on the outer circumference of the support member. The inspection apparatus of the 11th invention is characterized in that, in the first invention, the light source is an LED. The inspection apparatus of the 12th invention is characterized in that, in the first invention, two or more temperature measuring instruments are provided within the light source device. The inspection apparatus of the 13th invention further comprises a light intensity measuring instrument for measuring the amount of inspection light emitted from the light source, and the control device is characterized in that it uses the temperature measured by the temperature measuring instrument and the amount of light measured by the light intensity measuring instrument to maintain the temperature of the light source within a predetermined temperature range using the temperature controller. [Effects of the Invention]

[0007] According to the first invention, the light source of the light source device constituting the inspection apparatus is maintained within a predetermined temperature range based on the temperature measured by a temperature measuring instrument that measures the temperature of the light source, etc. This stabilizes the spectral characteristics of the inspection light emitted from the light source, enabling high-precision inspections during long periods of time and inspections during the startup of the inspection apparatus. According to the second invention, by using a line light source, the inspection range of the object being inspected can be widened. According to the third invention, since the line light source is configured with light-emitting elements arranged in a line, there is no need to separate the light source and the light-emitting elements, and the overall size of the light source can be made more compact. According to the fourth invention, by including a two-dimensional sensor in the imaging device, the inspection range of the object to be inspected can be made wider. According to the fifth invention, in a temperature controller, heat is transferred by a liquid, and since liquids have a higher specific heat than gases, it is possible to transfer heat effectively. According to the sixth invention, in a temperature controller, since heat is transferred by gas, there is no need to consider leaks in the part through which the gas passes, compared to the case of a liquid, and the structure of that part can be manufactured at low cost. According to the seventh invention, in a temperature controller, since heat transfer is carried out by a solid, the number of auxiliary devices can be reduced compared to cases where gas or liquid is used, and the overall configuration can be simplified. According to the eighth invention, the temperature controller is a Peltier element, which allows it to both remove and supply heat. According to the ninth invention, the support member has a predetermined surrounding structure, and the temperature controller is in contact with the light source inside the support member, thereby improving the responsiveness of temperature control of the light source. According to the tenth invention, the support member has a predetermined surrounding structure, and the temperature controller is provided on the outer circumference of the support member, thereby facilitating access to the temperature controller by the worker and improving maintainability. According to the 11th invention, since the light source is an LED, the amount of heat generated by the light source can be reduced, the stability of the spectral characteristics of the inspection light to be irradiated can be increased, and it becomes easy to miniaturize the light source. According to the 12th invention, since two or more temperature measuring devices are provided in the light source device, unevenness in the temperature distribution of the light source device can be suppressed. According to the 13th invention, it further includes a light quantity measuring device that measures the light quantity of the inspection light emitted from the light source, and the control device uses the temperature measured by the temperature measuring device and the light quantity measured by the light quantity measuring device to maintain the temperature of the light source within a predetermined temperature range by the temperature regulator, thereby enabling more precise adjustment of the temperature of the light source.

Brief Description of the Drawings

[0008] [Figure 1] It is a cross-sectional view of a light source device that constitutes an inspection device according to the first embodiment of the present invention. [Figure 2] It is a plan view of an inspection device according to the first embodiment of the present invention. [Figure 3] It is a front view of the inspection device in FIG. 2. [Figure 4] It is a perspective view of the inspection device in FIG. 2. [Figure 5] It is an explanatory view of an imaging device that constitutes the inspection device in FIG. 2. [Figure 6] It is a control block configuration diagram of the inspection device in FIG. 2. [Figure 7] It is a front view of an inspection device according to the second embodiment of the present invention. [Figure 8] It is a cross-sectional view of a light source device that constitutes an inspection device according to the third embodiment of the present invention. [Figure 9] It is a cross-sectional view of a light source device that constitutes an inspection device according to the fourth embodiment of the present invention. [Figure 10] It is a cross-sectional view of a light source device that constitutes an inspection device according to the fifth embodiment of the present invention. [Figure 11] It is a cross-sectional view of a light source device that constitutes a conventional inspection device.

Modes for Carrying Out the Invention

[0009] Next, embodiments of the present invention will be described based on the drawings. However, the embodiments shown below illustrate an inspection apparatus for embodying the technical idea of the present invention, and the present invention is not limited to the following inspection apparatus. Note that the size or positional relationship of the members shown in each drawing may be exaggerated for clarity of explanation.

[0010] (First Embodiment) FIG. 2 shows a plan view of an inspection apparatus 10 according to a first embodiment of the present invention, FIG. 3 shows a front view thereof, and FIG. 4 shows a perspective view thereof. The inspection apparatus 10 corresponds to, for example, a wafer measurement apparatus that calculates the thickness of a film provided on a wafer W from spectroscopic data of linear measurement light. In this case, the measurement light may be described as one of the inspection lights. In the following description, this wafer measurement apparatus will be described as the inspection apparatus 10 of the first embodiment. For ease of understanding, only the main members of the wafer measurement apparatus are shown in FIGS. 2 to 4. This wafer measurement apparatus is a measurement apparatus that can measure the thickness of a film provided on the wafer W or the thickness of the wafer W itself from spectroscopic characteristic data of linear inspection light reflected by the wafer W to be inspected. Measurement apparatuses that measure the thickness of a film provided on the wafer W or the like from this spectroscopic characteristic data include, in addition to the white interference method and the spectroscopic interference method, a method using confocal.

[0011] The measurement target of the inspection apparatus 10 according to this embodiment, that is, the wafer measurement apparatus, is the wafer W. A "wafer" is "a circular thin plate made of a crystal of a semiconductor substance, which is a material for an IC chip (semiconductor integrated circuit)". The wafer W is provided with a notch called a notch or a straight portion called an orientation flat on its circumference to align the orientation of the wafer W during the process.

[0012] In this embodiment, as shown in Figures 2 to 4, the wafer W is moved by the transport robot 16 in the direction indicated by the arrows, that is, from bottom to top in Figure 2, and from right to left in Figure 3. In Figure 2, the direction perpendicular to the direction indicated by the arrows is the linear direction of the line-shaped inspection light. In the portion of the wafer W whose thickness is measured by the wafer measuring device, the wafer W moves as shown by the arrows. In other words, in this embodiment, the thickness of a film or the like provided on the wafer W is measured in accordance with the movement of the wafer W, which is the object to be measured, in a direction perpendicular to the linear direction of the light source device 11.

[0013] The inspection apparatus 10 according to this embodiment has an apparatus body. The apparatus body is composed of a light source device 11 that emits linear inspection light, and an imaging device 20 that receives the linear inspection light reflected by the wafer W. In Figure 2, the linear direction of the light source device 11 that emits linear inspection light is in the left-right direction, and in Figure 3, it is in the depth direction.

[0014] Figure 1 shows a cross-sectional view of the light source device 11 that constitutes the inspection apparatus 10 according to this embodiment. This cross-sectional view is section II of Figure 2. The light source device 11 includes a light source 30 that irradiates inspection light onto the wafer W to be inspected, and a support member 31 that houses the light source 30. In this embodiment, the support member 31 is a so-called housing and has an enclosing structure for emitting inspection light from the light source 30 in a predetermined direction. In Figure 1, the enclosing structure of the support member 31 causes inspection light to be irradiated from the opening 34 downwards on the plane of the paper. In this embodiment, the light source device 11 includes a temperature measuring instrument 32 for measuring the temperature of the light source 30, and a temperature controller 33 for maintaining the temperature of the light source 30 within a predetermined temperature range based on the temperature measured by the temperature measuring instrument 32. The material of the support member 31 is not particularly limited, but aluminum, resin, stainless steel, iron, copper, titanium, carbon, ceramic, etc. can be used as appropriate. Note that only the main components constituting the light source device 11 are shown in Figure 1. At the joints of each component of the light source device 11, heat dissipation sheets, heat dissipation rubber, graphite sheets, heat dissipation grease, etc., may be used to improve thermal conductivity.

[0015] The light source 30 of the light source device 11 that constitutes the inspection device is maintained within a predetermined temperature range based on the temperature measured by a temperature measuring instrument 32 that measures the temperature of the light source 30, etc. This stabilizes the spectral characteristics of the inspection light emitted from the light source 30, enabling high-precision inspections during long periods of time and during the startup of the inspection device.

[0016] In this embodiment, the light source 30 is a line light source. Being a line light source allows for a wider inspection range for the object under inspection. However, the light source 30 is not limited to a line light source. For example, depending on the type of inspection device, it may be a point light source. Furthermore, in this embodiment, the light source 30 is a line light source configured with light-emitting elements arranged in a line. This configuration eliminates the need to separate the light source and light-emitting elements, allowing for a more compact overall light source. However, the line light source is not limited to this configuration. For example, a light guide type line light source using optical fibers is also acceptable.

[0017] In this embodiment, the light source 30 is an LED. By using an LED as the light source 30, the amount of heat generated by the light source 30 can be reduced, the stability of the spectral characteristics of the irradiated inspection light can be increased, and the light source can be easily miniaturized. Furthermore, it becomes easier to reduce the size of the light source 30, increase the light intensity, and reduce manufacturing costs. However, the light source 30 is not limited to an LED. For example, any light source that emits a line-shaped inspection light is acceptable, such as a fluorescent lamp, halogen light source, metal halide lamp, laser light source, incandescent bulb, sodium lamp, xenon lamp, or organic EL. When the light source 30 is a halogen light source, it is suitable for thickness measurement because the wavelength of the emitted inspection light is broad and the intensity at each wavelength is relatively uniform compared to other light sources. It is preferable to use a cylindrical lens or rod lens at the tip of the light source 30, because the amount of light received by the imaging device 20 is increased. It is also preferable to irradiate uniform light by installing a light-diffusing plate material such as a diffuser or diffuser plate between the light source device 11 and the wafer W. This is because uniform illumination of the light makes it possible to obtain stable measurement results. In Figure 2, the dashed line drawn from the light source device 11 to the imaging device 20 represents the inspection light emitted from the light source device 11 that is received by the imaging device 20 when the wafer W is of sufficient size; in reality, the inspection light emitted from the light source device 11 extends beyond these dashed lines. The inspection light emitted from the light source 30 is preferably visible light. However, it is not limited to visible light; near-infrared broad, mid-infrared, far-infrared, ultraviolet, or X-ray light are also acceptable. Among these, visible light or near-infrared light is preferred.

[0018] In this embodiment, the temperature measuring device 32 that measures the temperature of the light source 30 is a thermocouple. However, the temperature measuring device 32 is not limited to a thermocouple. For example, a non-contact infrared thermometer or thermistor is also acceptable. In this embodiment, the temperature measuring device 32 is provided so as to be in direct contact with the light source 30. By having the temperature measuring device 32 in contact with the light source 30 inside the support member 31, the responsiveness of the temperature control of the light source 30 can be improved. Note that the installation method of the temperature measuring device 32 is not limited to the case where it is in direct contact with the light source 30 as described above. Furthermore, in this embodiment, one temperature measuring device 32 is provided inside the light source device 11. However, the number of temperature measuring devices 32 is not limited to one. For example, it is possible to provide two or more at different positions in a linear direction. By providing two or more temperature measuring devices 32 inside the light source device 11, unevenness in the temperature distribution of the light source device 11 can be suppressed.

[0019] In this embodiment, the temperature controller 33, which maintains the temperature of the light source 30 within a predetermined temperature range, uses a solid to transfer heat. A Peltier element is used as this temperature controller 33. The Peltier element temperature controller 33 maintains the temperature of the light source 30 within a predetermined temperature range based on the temperature measured by the temperature measuring instrument 32, as controlled by the control device 12. The temperature controller 33, which uses a solid to transfer heat, is not limited to a Peltier element. For example, a ceramic heater can be used as such a temperature controller 33.

[0020] In the temperature controller 33, heat transfer is carried out by a solid, which reduces the number of auxiliary components compared to cases using gases or liquids, thus simplifying the overall configuration. Furthermore, because the temperature controller 33 is a Peltier element, it can both remove and supply heat.

[0021] Figure 5 shows a configuration diagram of the imaging device 20 according to this embodiment. Figure 5 is a cross-sectional view of the imaging device 20 from the side. In Figure 5, the inspection light is shown by a dashed line. The imaging device 20 receives the inspection light emitted from the light source device 11 by reflecting it off the wafer W. The reception is performed by spectrally analyzing the inspection light. As shown in Figure 5, the imaging device 20 is housed in a housing 27 and includes a first lens 21 that focuses the inspection light that has passed through the object to be measured, a slit 22 that cuts out unnecessary parts of the focused inspection light to improve spectral accuracy, a second lens 23 that corrects the direction of the inspection light that has passed through the slit 22 to a direction suitable for incident on the grating element 24, a grating element 24 that spectrally analyzes the inspection light according to wavelength, a third lens 25 for focusing the spectrally analyzed inspection light onto a two-dimensional sensor 26, and a two-dimensional sensor 26 that receives the spectrally analyzed inspection light.

[0022] The two-dimensional sensor 26 has a configuration having predetermined lengths in the left-right and depth directions on the plane of Figure 5, and in this embodiment, a CMOS is used as the element. However, the element is not limited to CMOS. For example, CCD, InGaAs, InSb, MCT, QWIP, microbolometer, etc. can also be used. When a CCD or CMOS is used as the element of the two-dimensional sensor 26, cooling of the two-dimensional sensor 26 becomes unnecessary, making it possible to reduce the manufacturing cost of the wafer measurement device. In particular, when a CMOS is used, it is possible to perform ROI (Region of Interest) in either the left-right or depth direction, and it is possible to speed up imaging by focusing on the necessary sensor area.

[0023] Because the imaging device 20 includes a two-dimensional sensor 26, the inspection range of the object being inspected can be made wider.

[0024] The first lens 21, second lens 23, and third lens 25 used in the imaging device 20 can be any lens capable of focusing and manipulating the inspection light. Alternatively, curved mirrors can be used instead of these lenses. Using curved mirrors increases design flexibility and makes it possible to miniaturize the imaging device 20.

[0025] In this embodiment, the grating element 24 is a transmissive type. When the grating element 24 is a transmissive type, the imaging device 20 can handle a wide range of wavelengths and has a simpler structure. However, it is not limited to this, and a reflective grating element can also be used. Examples of reflective grating elements include blazed diffraction gratings and holographic diffraction gratings. By using a reflective grating element, the degree of design freedom increases, and it becomes possible to miniaturize the imaging device 20.

[0026] In this embodiment, the housing 27 of the imaging device 20 is made of aluminum. The use of aluminum for the housing 27 provides good heat dissipation and workability, and also helps to reduce costs. However, it is not limited to aluminum; resin, stainless steel, etc., can also be used. Furthermore, instead of the grating element 24, a linear variable filter (LVF) can be used for spectroscopy, or a metamaterial can be used for spectroscopy.

[0027] Figure 6 shows a control block diagram of the inspection apparatus 10 according to this embodiment. The inspection apparatus 10 of this embodiment has a control device 12. This control device 12 is composed of a CPU and the like. The control device 12 is electrically connected to the light source device 11, the imaging device 20, the display device 13, the data storage device 14, and the input device 15. The control device 12 is also electrically connected to the temperature measuring instrument 32 and the temperature controller 33 that make up the light source device 11. In Figure 6, the line connecting the control device 12 to the light source device 11 is represented by a single solid line, but this solid line contains multiple wires. The control device 12 can calculate the thickness of the object to be measured by analyzing the spectral characteristic data of the inspection light measured by the two-dimensional sensor 26 of the imaging device 20. Furthermore, it is preferable that the control device 12 is provided with an output unit (not shown) for outputting information such as film thickness data, average value, maximum value, minimum value of film thickness, size, shape, and position of abnormal film thickness to devices other than the inspection apparatus 10.

[0028] In this embodiment, the display device 13 is a liquid crystal display, and can display the thickness data of the object under inspection in two dimensions or three dimensions based on signals from the control device 12. However, the display device 13 is not limited to a liquid crystal display. For example, an organic EL display may also be used.

[0029] In this embodiment, the data storage device 14 is a hard disk and is capable of storing compressed data of the thickness data of the object to be measured, which is calculated by the control device 12. However, the data storage device 14 is not limited to a hard disk. For example, a Blu-ray disc drive or an SSD (Solid State Drive) may be used.

[0030] In this embodiment, the input device 15 is a touch panel, and the user of the inspection device 10 issues commands via this input device 15, which the control device 12 then uses to control the light source device 11, the imaging device 20, and the operating device. However, the input device 15 is not limited to a touch panel. For example, a keyboard and mouse could also be used.

[0031] (How to use the inspection device 10) The user of the inspection device 10 activates the control device 12 of the inspection device 10, sends a command from the input device 15, and irradiates the wafer W to be inspected with inspection light from the light source device 11. The inspection light that has passed through the wafer to be inspected is received by the imaging device 20. The control device 12 then analyzes the spectral characteristics data of the inspection light measured by the imaging device 20 and calculates the thickness of the wafer to be inspected. This thickness and other data are then displayed on the display device 13 or stored in the data storage device 14.

[0032] Furthermore, during the inspection described above, the control device 12 controls the temperature controller 33 based on the temperature measured by the temperature measuring instrument 32 in the light source device 11, maintaining the temperature of the light source 30 within a temperature range specified in advance by the user. This temperature range is preferably about ±5 degrees, more preferably about ±1 degree, and even more preferably about ±0.1 degrees. This is because a narrower temperature range allows for more stable spectral identification of the inspection light emitted from the light source 30.

[0033] (Second Embodiment) Figure 7 shows a schematic side view of an inspection apparatus 10 according to a second embodiment of the present invention. In the first embodiment, the imaging device 20 receives inspection light reflected from the object to be inspected, whereas in the second embodiment, the imaging device 20 receives inspection light that has passed through the object to be inspected. As shown in Figure 7, the inspection apparatus 10 according to the second embodiment includes, on the underside of the object to be inspected, a light source device 11 that irradiates the object to be inspected with inspection light, an imaging device 20 that receives inspection light from the object to be inspected, and a control device 12 that calculates the thickness based on the signal from the imaging device 20. In this embodiment, the line connecting the light source device 11 and the imaging device 20 intersects perpendicularly with respect to the object to be inspected. The details of the configuration, such as the light source device 11, are the same as in the first embodiment.

[0034] (Third embodiment) Figure 8 shows a cross-sectional view of the light source device 11 that constitutes the inspection apparatus 10 according to the third embodiment of the present invention. The other components of the inspection apparatus 10 are the same as those of the first embodiment, so their description is omitted.

[0035] The light source device 11 of this embodiment includes a light source 30 that irradiates inspection light onto the wafer W to be inspected, and a support member 31 that houses the light source 30. The support member 31 has an enclosure structure for emitting inspection light from the light source 30 in a predetermined direction. In Figure 8, the enclosure structure of the support member 31 causes inspection light to be irradiated from the opening 34 downwards on the plane of the paper. In this embodiment, the light source device 11 includes a temperature measuring instrument 32 for measuring the temperature of the light source 30, and a temperature controller 33 for maintaining the temperature of the light source 30 within a predetermined temperature range based on the temperature measured by the temperature measuring instrument 32.

[0036] In this embodiment, the temperature controller 33, which maintains the temperature of the light source 30 within a predetermined temperature range, uses a liquid to transfer heat. The temperature controller 33 has through holes 35 through which a liquid such as cooling water passes, arranged in a linear direction. The temperature controller 33 maintains the temperature of the light source 30 within a predetermined temperature range by allowing the liquid to pass through the through holes 35 based on the temperature measured by the temperature measuring instrument 32, controlled by the control device 12. Because the temperature controller 33 uses a liquid to transfer heat, and liquids have a higher specific heat than gases, heat transfer can be carried out effectively. In this embodiment, water is used as the liquid, but the liquid is not limited to this. For example, glycol, oil, or liquid nitrogen can also be used.

[0037] While we have described the case where heat is transferred using a liquid, there are also cases where heat is transferred using a gas. Compared to the case of a liquid, there is no need to consider leaks in the parts through which the gas passes, and the components of those parts can be manufactured at a lower cost. In the case of a gas, it is also possible to use the gas as a refrigerant and lower its temperature with a compressor.

[0038] (Fourth Embodiment) Figure 9 shows a cross-sectional view of the light source device 11, which constitutes the inspection apparatus 10 according to the fourth embodiment of the present invention. The other components of the inspection apparatus 10 are the same as those of the first embodiment, so their description is omitted.

[0039] The light source device 11 of this embodiment includes a light source 30 that irradiates inspection light onto a wafer W to be inspected, and a support member 31 that houses the light source 30. The support member 31 has an enclosure structure for emitting inspection light from the light source 30 in a predetermined direction. In Figure 9, the enclosure structure of the support member 31 causes inspection light to be irradiated from the opening 34 downwards on the plane of the paper. In this embodiment, the light source device 11 includes a temperature measuring instrument 32 for measuring the temperature of the light source 30, and a temperature controller 33 for maintaining the temperature of the light source 30 within a predetermined temperature range based on the temperature measured by the temperature measuring instrument 32.

[0040] In this embodiment, the temperature controller 33 for maintaining the temperature of the light source 30 within a predetermined temperature range is provided on the outer circumference of the support member 31 so as to be in contact with the support member 31 that supports the light source 30. By providing the temperature controller 33 on the outer circumference of the support member 31, access to the temperature controller 33 by the operator is made easier, improving maintainability. In this embodiment, a Peltier element is used as the temperature controller 33, but this is not the only option. For example, other methods of heat transfer using a solid, such as a ceramic heater, can also be used. In addition, methods of heat transfer using a liquid or a gas may also be used.

[0041] (Fifth embodiment) Figure 10 shows a cross-sectional view of the light source device 11 that constitutes the inspection apparatus 10 according to the fifth embodiment of the present invention. The other components of the inspection apparatus 10 are the same as those of the first embodiment, so their description is omitted.

[0042] The light source device 11 of this embodiment includes a light source 30 that irradiates inspection light onto a wafer W to be inspected, and a support member 31 that houses the light source 30. The support member 31 has an enclosure structure for emitting inspection light from the light source 30 in a predetermined direction. In Figure 10, the enclosure structure of the support member 31 causes inspection light to be irradiated from the opening 34 downwards on the plane of the paper. In this embodiment, the light source device 11 includes a temperature measuring instrument 32 for measuring the temperature of the light source 30, and a temperature controller 33 for maintaining the temperature of the light source 30 within a predetermined temperature range based on the temperature measured by the temperature measuring instrument 32.

[0043] In this embodiment, the inspection device 10 further includes a light intensity meter 36 that measures the amount of inspection light emitted from the light source 30. The control device 12 uses the light intensity measured by the light intensity meter 36 and the temperature measured by the temperature measuring instrument 32 to maintain the temperature of the light source 30 within a predetermined temperature range using a temperature controller 33. With this configuration, the temperature of the light source 30 can be adjusted with higher precision.

[0044] In Figure 10, the light intensity meter 36 is located near the aperture 34 of the light source device 11, but the configuration is not limited to this. For example, the light intensity meter 36 can also be located on the outer periphery of the light source device 11, on the side of the imaging device 20. In this embodiment, a Peltier element is used as the temperature controller 33, but the configuration is not limited to this. For example, other methods of heat transfer using solids, such as a ceramic heater, can be used. Methods of heat transfer using liquids or gases may also be used.

[0045] (others) Although the above embodiment was described using a wafer thickness measuring device W as an example, the inspection device 10 is not limited to this. For example, a defect inspection device using a light source device 11 and an imaging device 20 is also included in the inspection device 10. Furthermore, although an embodiment of the temperature controller 33 consisting of a Peltier element alone was described, it is not limited to this, and a combination of a Peltier element and a heat sink is also included, for example. [Explanation of Symbols]

[0046] 10 Inspection equipment 11 Light source device 12 Control device 20 Imaging device 26 Two-dimensional sensors 30 light source 31 Support member 32 Temperature measuring device 33 Temperature regulator 35 Passing hole

Claims

1. A light source device equipped with a light source that irradiates the object to be inspected with inspection light, An imaging device that receives the inspection light that has passed through the object to be inspected, The system comprises a control device for controlling the light source device and the imaging device, The aforementioned light source device is The aforementioned light source, A temperature measuring instrument, The device includes a temperature controller for maintaining the temperature of the light source within a predetermined temperature range based on the temperature measured by the temperature measuring instrument, The temperature measuring device measures the temperature of at least one of the light source, the support member supporting the light source, or the temperature controller. The control device maintains the temperature of the light source within a predetermined temperature range using the temperature regulator. An inspection device characterized by the following features.

2. The aforementioned light source is a line light source. The inspection apparatus according to feature 1.

3. The aforementioned line light source is configured such that light-emitting elements are arranged in a line. The inspection apparatus according to feature 2.

4. The imaging device includes a two-dimensional sensor. The inspection apparatus according to feature 1.

5. In the aforementioned temperature controller, heat is transferred by a liquid. The inspection apparatus according to feature 1.

6. In the aforementioned temperature controller, heat is transferred by gas. The inspection apparatus according to feature 1.

7. In the aforementioned temperature controller, heat transfer is carried out by a solid. The inspection apparatus according to feature 1.

8. The aforementioned temperature controller is a Peltier element. The inspection apparatus according to feature 7.

9. The support member has an enclosing structure for emitting the inspection light from the light source in a predetermined direction. The temperature controller is located inside the support member and is in contact with the light source. The inspection apparatus according to feature 1.

10. The support member has an enclosing structure for emitting the inspection light from the light source in a predetermined direction. The temperature controller is provided on the outer circumference of the support member. The inspection apparatus according to feature 1.

11. The aforementioned light source is an LED. The inspection apparatus according to feature 1.

12. The temperature measuring device is provided in two or more locations within the light source device. The inspection apparatus according to feature 1.

13. The system further includes a light intensity measuring device for measuring the amount of light emitted from the light source, The control device is Using the temperature measured by the temperature measuring instrument and the light intensity measured by the light intensity measuring instrument, the temperature controller maintains the temperature of the light source within a predetermined temperature range. The inspection apparatus according to feature 1.

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