JP4722419B2 - Solid immersion lens - Google Patents

Description

  The present invention relates to a solid immersion lens used for a semiconductor device inspection method used for failure analysis and reliability evaluation of a semiconductor device.

  Conventionally, as a semiconductor device inspection apparatus, an emission microscope, an OBIRCH analysis apparatus, a time-resolved emission microscope, and the like are known (see Patent Documents 1, 2, and 3). However, in recent years, semiconductor devices to be inspected have been miniaturized, and conventional inspection apparatuses using visible light, infrared light, or heat rays have a fine structure due to limitations due to diffraction limits in the optical system. The analysis of is becoming difficult.

  For this reason, when detecting an abnormal part occurring in a circuit pattern such as a transistor or wiring formed in a semiconductor device having such a fine structure, first, an inspection apparatus using visible light, infrared light, or heat rays To narrow the range where the abnormal part exists to some extent. And the method of inspect | inspecting the abnormal location in a semiconductor device by observing the narrowed-down range using a higher-resolution electron microscope etc. is used.

  In the method described above, that is, the method of performing high-resolution observation with an electron microscope after performing inspection using light, the preparation and installation of the semiconductor device to be inspected are complicated, and it is very difficult to inspect the semiconductor device. There is a problem that it takes a lot of trouble and time.

  Also, in order to avoid shielding objects such as multilayer wiring formed on the semiconductor device, an objective lens is arranged on the back side of the semiconductor device, and it is necessary to observe the back side to observe the light emitted from the device through the substrate of the semiconductor device. It is increasing.

On the other hand, a solid immersion lens (SIL) is known as a lens for enlarging an image to be observed. The solid immersion lens is generally known as a hemispherical lens or a super hemispherical lens called a Weierstrass sphere. If this solid immersion lens is optically coupled to the surface of the object to be observed, both the numerical aperture NA and the magnification can be enlarged, and observation with high spatial resolution becomes possible. As a semiconductor inspection apparatus using such a solid immersion lens, for example, there are those described in Patent Documents 4 and 5.
JP-A-7-190946 JP-A-6-300824 Japanese Patent Laid-Open No. 10-150086 Japanese Patent Publication No. 7-18806 US Pat. No. 6,594,086

  The solid immersion lens disclosed in Patent Document 4 is a plano-convex lens and has a flat mounting surface (bottom surface) for an observation object. When observing the back side of a semiconductor device using a solid immersion lens, if there is a gap between the solid immersion lens and the semiconductor substrate, incident light above the critical angle is totally reflected and only incident light below the critical angle can propagate. The effective numerical aperture is limited by the critical angle. However, when the gap between the solid immersion lens and the back surface of the semiconductor substrate is approximately the same as the wavelength of light in the semiconductor, the light can propagate by evanescent coupling.

  However, in the gap between the plano-convex lens and the back surface of the semiconductor substrate, there is a large gap due to a wide confrontation area, and in such a large gap, the transmitted light intensity rapidly decreases and becomes critical. Only incident light below the corner can propagate, limiting the effective numerical aperture. As described above, in the inspection using the plano-convex lens, the surface accuracy of the bottom surface of the plano-convex lens is required to be high, resulting in an increase in manufacturing cost. Furthermore, since the surface accuracy of the contact surface is also required for the semiconductor substrate, there is a problem that a great deal of labor is required in the pretreatment (semiconductor substrate polishing) for inspecting the semiconductor device.

  In addition, even if the surface accuracy of the plano-convex lens bottom surface and the contact surface on the substrate can be made high, the air flow resistance is high when these are optically coupled, so that it takes a long time to obtain optical coupling. There is also a problem that it takes time.

  Therefore, in Patent Document 4 described above, as a technique for obtaining the original resolution of a solid immersion lens, a technique that uses refractive index matching by interposing a high refractive index fluid between a plano-convex lens and an observation object is described. . This method uses refractive index matching and is different from that using evanescent coupling. A typical high refractive index matching fluid includes an arsenic tripromide / disulfide / selenium compound system, but arsenic tribromide has a problem in handling because it is toxic and corrosive.

  Further, the solid immersion lens disclosed in Patent Document 5 is a bi-convex lens. In this lens, since the mounting surface has a convex shape that makes contact with the observation object at a point (point of contact), it is considered to be advantageous in securing optical connectivity as compared with a plano-convex lens. However, since the contact area with the object to be observed is very small, if the substrate of the semiconductor device to be observed becomes thick, it becomes impossible to pass a light beam with a high NA. There is a problem that cannot be obtained.

  In order to bring the solid immersion lens and the observation object into close contact with each other over a wide area, it is necessary to apply pressure between the bottom surface of the solid immersion lens and the observation object. Here, as shown in FIG. 17, as the curvature radius of the lens decreases, the pressure required for close contact increases. FIG. 17 shows the pressure necessary to bring the bottom surface of the solid immersion lens up to 2 mm in diameter into close contact with the flat surface of the observation object. In the backside analysis of a semiconductor device using a solid immersion lens, it is necessary to apply pressure to the semiconductor substrate with sufficient consideration of the strength during handling. This is because if an excessive pressure is applied, there is a risk of damaging the integrated circuit formed on the surface of the semiconductor substrate. Considering the trend of thinning semiconductor devices, bi-convex lenses cannot achieve the resolution inherent to solid immersion lenses.

  Moreover, although distortion occurs in the semiconductor device due to the pressure, this state is different from the mounting state of the semiconductor device, and therefore, it is not possible to satisfy the requirement to inspect under the same operating conditions as the mounting state. In a distorted state, it may even lead to results that are contrary to the intended purpose of the test.

  Furthermore, this lens has a problem that the positional relationship with the semiconductor substrate is not uniquely determined due to the shape characteristics. When it is attached to be inclined with respect to the contact surface of the semiconductor substrate, optical coupling at the center of the bottom surface of the solid immersion lens cannot be obtained. In order to avoid this, precise position control of the solid immersion lens is required, which leads to an increase in the size and cost of the apparatus.

  The present invention has been made to solve the above-described problems, and allows the light beam to pass therethrough with a desired numerical aperture and facilitates position control when optically coupled to the sample to be observed. An object is to provide a solid immersion lens.

In order to achieve such an object, a solid immersion lens according to the present invention is a solid immersion lens that is attached to a sample to be observed and is used for observation of the sample, and is (1) a first spherical surface having a predetermined radius. And (2) a second surface having a plurality of protrusions, and (3) a second surface, each of the plurality of protrusions being separated from the central axis. The contact pattern with respect to the sample by the plurality of protrusions provided at a distant position is symmetrical with respect to the central axis, and is formed so that the center portion of the second surface and the sample do not contact each other. Features.

  In the solid immersion lens described above, a plurality of protrusions are provided on the mounting surface for the sample, instead of a single protrusion as in the bi-convex lens. In such a configuration, when the solid immersion lens is optically coupled to the sample, a contact pattern corresponding to the installation pattern of the plurality of protrusions on the mounting surface appears. Therefore, a contact pattern can be set according to the number and arrangement of protrusions, and a light beam passing through a desired optical path can be obtained. For example, a light beam having a high numerical aperture can also be obtained by arranging the protruding portion according to the numerical aperture. In addition, since the solid immersion lens is brought into contact with the sample via the plurality of protrusions, the position control of the solid immersion lens becomes easy. In addition, since the projection is optically coupled to the sample at the protrusion on the mounting surface, the optical coupling can be released by a very weak force with respect to the solid immersion lens after observation. Therefore, there is no possibility of damaging the sample and the solid immersion lens when removing the solid immersion lens.

  Furthermore, in the above configuration, the plurality of protrusions on the mounting surface for the sample are arranged so that the installation pattern and the contact pattern for the sample are axially symmetric with respect to the central axis of the solid immersion lens. Thereby, even when the observation position is at a predetermined distance from the mounting surface with respect to the observation position of the sample on the central axis of the solid immersion lens, it is possible to suitably execute the observation of the sample. This is extremely effective when, for example, backside observation is performed on a sample such as a semiconductor device. In the above configuration, the number, shape, and arrangement of the plurality of protrusions, and the contact pattern of the solid immersion lens by the plurality of protrusions to the sample are set in accordance with the optical path to be used for sample observation. It is possible. This makes it possible to arbitrarily and selectively set observation conditions such as the optical path and numerical aperture for sample observation under desired conditions.

  In addition, when the solid immersion lens described above is applied to a microscope, the microscope is a microscope for observing a sample to be observed, and includes an objective lens on which light from the sample is incident, and an optical system that guides an image of the sample And the solid immersion lens described above. This makes it possible to observe the sample under suitable observation conditions.

  According to the present invention, it is possible to provide a solid immersion lens that is easy to control the position and can pass a light beam with a desired numerical aperture.

  Hereinafter, preferred embodiments of a solid immersion lens according to the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the dimensional ratios in the drawings do not necessarily match those described.

  FIG. 1A is a bottom view and FIG. 1B is a side view showing the configuration of a first embodiment of a solid immersion lens according to the present invention. Moreover, in FIG.1 (b), it has shown in the state which attached the solid immersion lens to the sample. In each of the following embodiments, if necessary, an x-axis and a y-axis orthogonal to the central axis are attached to the bottom view of the solid immersion lens, and the configuration will be described with reference to these axes. However, these x-axis and y-axis are for convenience of explanation. Moreover, in each figure, the protrusion part is shown with diagonal lines for easy viewing.

  The solid immersion lens 1 </ b> A according to the present embodiment is attached to the sample 6 to be observed and used for observing the sample 6. The solid immersion lens 1 </ b> A includes an upper surface (first surface) 2 that serves as an input / output surface for light with respect to the outside (for example, an objective lens of a microscope) and a bottom surface (second surface) 3 that serves as an attachment surface for the sample 6. And is formed of a material having a refractive index n. Here, the central axis of the lens shape in the solid immersion lens 1A is an axis Ax as shown in FIG.

  The upper surface 2 is formed in a spherical shape having a radius of curvature R with the point O on the central axis Ax as a sphere. The bottom surface 3 is formed so as to substantially coincide with a surface that passes through the spherical center O of the top surface 2 and is perpendicular to the central axis Ax. Thereby, the solid immersion lens 1A of the present embodiment has a hemispherical lens shape. The radius R of the upper surface 2 of the solid immersion lens 1A is preferably 0.05 mm or more and 0.5 mm or less. Alternatively, the radius R may be set outside this range.

  Further, in the solid immersion lens 1A, the bottom surface 3 serving as a mounting surface for the sample 6 is formed with a plurality of protrusions. That is, in the configuration shown in FIG. 1, two projecting portions 4 a and 4 b projecting downward are provided on the bottom surface 3. In these protrusions 4a and 4b, the contact pattern with respect to the sample 6 by the protrusions 4a and 4b is axially symmetric with respect to the center axis Ax at a position sandwiching the center O of the center axis Ax and the center position of the bottom surface 3. It is formed as follows.

  Specifically, the protrusions 4a and 4b on the bottom surface 3 are on a straight line inclined at an angle θ in the negative direction of the y axis as viewed from the x axis, as shown in FIG. Centering on a position sandwiching the axis Ax at a distance L from Ax, each is formed in a circular shape with a radius r (where r <R / 2, r <L). As a result, the installation pattern of the two protrusions 4a and 4b is the center position of the bottom surface 3 as viewed from the direction of the central axis Ax and the center of the top surface 2 as shown in FIG. Is point-symmetric. Further, the contact pattern of the bottom surface 3 with respect to the sample 6 when the solid immersion lens 1A is attached to the sample 6 is that the center axis Ax intersects the surface to be attached of the sample 6 when viewed from the direction of the center axis Ax. It is point-symmetric.

  As for the specific protruding structure of the protruding portions 4a and 4b, various structures can be used as shown in FIGS. 2A to 2C are cross-sectional views of the solid immersion lens 1A shown in FIG. However, in these drawings, the structure of the protrusions 4a and 4b described above is shown enlarged in the direction of the central axis Ax, and the contact pattern with respect to the sample is shown by hatching. 2B and 2C, the upper portion of the solid immersion lens 1A is not shown.

  In the configuration shown in FIG. 2A, the projecting portions 4a and 4b are formed so that the cross-sectional shape thereof is a semi-elliptical curved surface shape. In the configuration shown in FIG. 2B, the projecting portions 4a and 4b are formed to have a tapered trapezoidal shape whose cross-sectional shape becomes narrower downward. On the other hand, in the configuration shown in FIG. 2C, the projecting portions 4a and 4b are formed so that the cross-sectional shape thereof is rectangular. Alternatively, shapes other than these may be used. In addition, about the protrusion height from the bottom face 3 of protrusion part 4a, 4b, in order to fully implement | achieve the effect mentioned later by providing protrusion part 4a, 4b, it is preferable to set it as 10 nm or more. The upper limit of the protrusion height is preferably R / 2 or less with respect to the radius of curvature R of the upper surface 2 from the overall shape of the solid immersion lens 1A.

  Next, a sample observation method using the above-described solid immersion lens 1A will be described. Here, as shown in FIG. 1B, for example, in a plate-like sample 6 such as a semiconductor substrate, the upper surface 6a is a surface on which the solid immersion lens 1A is attached, and the lower surface 6b is an observation surface on which an observation position P is set. The case will be described. As an example of such sample observation, there is a case where the semiconductor device is the sample 6, the device surface is the lower surface 6b, and the back surface observation is performed from the upper surface 6a side.

  The mounting surface of the solid immersion lens 1A attached to the sample 6 is the bottom surface 3. The solid immersion lens 1A is in contact with the sample 6 at the projecting portions 4a and 4b installed on the bottom surface 3, and light propagates therethrough. In portions other than the protrusions 4a and 4b, the solid immersion lens 1A is not in contact with the upper surface 6a of the sample 6, and light having an incident angle greater than the critical angle is totally reflected by the bottom surface 3 and enters the sample 6. Not incident.

Furthermore, the contact pattern of the bottom surface 3 with respect to the sample 6 by the protrusions 4a and 4b is axially symmetric with respect to the central axis Ax, that is, point-symmetric with respect to a point corresponding to the observation position P on the upper surface 6a of the sample 6. . For this reason, the light incident from the protrusion 4a or 4b passes through the upper surface 6a of the sample 6, is reflected at the observation position P set on the lower surface 6b, and reaches the other protrusion 4b or 4a. Specifically, as shown in FIG. 1B, the light ₁₁ enters the solid immersion lens 1A, reaches the protrusion 4a, and enters the sample 6 through the protrusion 4a. Then, it reaches the observation position P on the lower surface 6b, is reflected there, and reaches the protrusion 4b. Then, the light enters the solid immersion lens 1A through the protrusion 4b, passes through the lens, and exits to the outside. On the other hand, light l ₂ reaches with a critical angle or more incident angles on the protrusion 4a, portions other than 4b on the bottom surface 3, where after totally reflected and emitted to the outside through the solid immersion lens 1A Go.

  Next, effects of the solid immersion lens 1A according to the present embodiment will be described.

  The solid immersion lens 1 </ b> A has two protrusions 4 a and 4 b instead of one protrusion like the bi-convex lens, and contacts the sample 6 at these two protrusions 4 a and 4 b. For this reason, it is possible to obtain a light beam passing through a desired optical path by changing the position and shape of these protrusions to adjust the contact pattern. For example, when it is desired to obtain a light beam having a high numerical aperture NA, it is only necessary to provide protrusions in the number and arrangement corresponding to the numerical aperture. Further, by bringing the solid immersion lens 1A into contact with the sample 6 through the two projecting portions 4a and 4b, the solid immersion lens 1A can be stably installed on the sample 6 without tilting. For this reason, position control of the solid immersion lens 1A is easier than the bi-convex lens.

  Furthermore, since the two protrusions 4a and 4b are in contact with the sample 6, the force required to separate the solid immersion lens 1A and the sample 6 is extremely weak compared to the plano-convex lens, and the solid immersion lens 1A can be removed. There is no risk of damaging the sample and the solid immersion lens 1A. In addition, the solid immersion lens 1A is in contact with the sample 6 only at the two protrusions, and the contact area is narrow compared to the case of the plano-convex lens. The possibility of hindering proper coupling is reduced.

  Further, the protrusions 4a and 4b of the solid immersion lens 1A are points on the upper surface 6a corresponding to the observation position P, with the contact pattern with respect to the sample 6 thereby being symmetric with respect to the central axis Ax of the solid immersion lens 1A. Are arranged so as to be point-symmetric with respect to. Therefore, the light incident from one projecting portion and reflected at the observation position P is emitted from the other projecting portion. As a result, observation at the observation position P set on the lower surface 6b of the sample 6 can be performed, and for example, the back surface analysis of the semiconductor device can be performed. Furthermore, by setting the positions and shapes of the protrusions 4a and 4b and the contact pattern of the bottom surface 3 to the sample 6 according to the optical path to be used for sample observation, the optical path and aperture for sample observation are set. The number and the like can be arbitrarily and selectively set under desired conditions.

  Further, in the solid immersion lens 1A shown in FIG. 1, the protrusions 4a and 4b are provided on the bottom surface 3 at positions separated from the central axis Ax by a distance L. In such a configuration, since the center portion of the bottom surface 3 and the sample 6 are not in contact with each other, the same effect as that obtained when the central shielding diaphragm is used can be obtained. That is, as in the case of using the central shielding stop that blocks the central light beam, the observation object is not illuminated by the central light beam, and the observation object can be observed brightly in a dark field of view. Therefore, for example, when this solid immersion lens 1A is applied to the backside observation of a semiconductor device, it is possible to eliminate the contrast of the metal wiring on the backside of the semiconductor substrate and selectively take out and observe the three-dimensional shape of the substrate. .

  Thus, a three-dimensional image can be obtained by using the solid immersion lens 1A according to the present embodiment. Further, by changing the position and shape of the protrusion and adjusting the incident angle of light to the observation position P, a desired image such as a two-dimensional image or a three-dimensional image can be obtained. For example, in the configuration shown in FIG. 1, parameters such as the distance L from the central axis Ax of the protrusions 4a and 4b and the radius r thereof may be set according to the image to be obtained.

Here, the overall shape of the solid immersion lens 1A is hemispherical in the above configuration example, but not limited to this, various shapes may be used. In general, the shape of the upper surface 2 of the solid immersion lens 1A is determined in consideration of the aberration caused by the lens, the observation position on the sample, and the like. For example, in the solid immersion lens 1A having a hemispherical shape, the spherical center O is an aberration object point, and at this time, the numerical aperture NA and the magnification are both n times. On the other hand, in a solid immersion lens having a super hemisphere, a position shifted downward from the spherical center by R / n is an aberration object point, and at this time, both the numerical aperture NA and the magnification are n ² times. Or you may use the structure which makes a focus the position between a spherical center and the position shifted | deviated below R / n from the spherical center.

  As the material of the solid immersion lens 1A, a material that transmits light used for observation may be appropriately selected depending on its refractive index and the like. For example, when observing a semiconductor device, a material having a high refractive index that is substantially the same as or close to the refractive index of the substrate material of the semiconductor device is preferably used as the material of the solid immersion lens. Examples thereof include Si, GaP, and GaAs. If the substrate is made of glass or plastic, glass or plastic is selected as the material for the solid immersion lens.

  In addition, regarding the number, arrangement, and shape of the protrusions provided on the bottom surface of the solid immersion lens, various configurations may be used according to the numerical aperture and optical path to be set in each solid immersion lens.

3A is a bottom view, and FIG. 3B is a cross-sectional view taken along the line II-II, showing a configuration of a modified example of the solid immersion lens shown in FIG. 1 as a reference example . In the solid immersion lens 1B, in addition to the projecting portions 4a and 4b, one projecting portion 4c is further provided at the center of the bottom surface 3 serving as a mounting surface for the sample. For example, the protrusion 4c is formed in a circular shape having a radius r with the sphere center O as the center. Even in such a configuration, the contact pattern of the bottom surface 3 with respect to the sample 6 by the protrusions 4a, 4b, and 4c is axisymmetric with respect to the central axis Ax. In the case of observing the sample, when it is desired to obtain an image by the central beam, it is preferable to have a structure having a protrusion at the center of the mounting surface as described above. As for the protruding structure of the protruding portion 4c, FIG. 3B illustrates a structure in which the cross-sectional shape is rectangular, but as shown in FIGS. 2A and 2B, a semi-elliptical shape is used. It is good also as a trapezoid shape of a shape or a taper shape.

FIG. 4 is a bottom view showing the configuration of another modified example of the solid immersion lens. In this solid immersion lens 1C, on the bottom surface 3, there are three sets of protrusions: a first set of protrusions 5a and 5b, a second set of protrusions 5c and 5d, and a third set of protrusions 5e and 5f. Is provided. Among these, the protruding portions 5a, 5b at a position sandwiching the axis Ax at a distance L ₁ from the center axis Ax, and is formed in a circular shape having a radius r _1, respectively. Further, the projecting portion 5c, 5d at a position sandwiching the axis Ax at a distance _{L 2} from the center axis Ax, and is formed in a circular shape having a radius _{r 2,} respectively. Further, the projecting portion 5e, 5f are at positions sandwiching the axis Ax at a distance _{L 3} from the central axis Ax, and is formed in a circular shape having a radius _{r 3,} respectively. In this manner, a plurality of sets of protrusions provided so as to sandwich the central axis on the bottom surface of the solid immersion lens may be used. In such a configuration, the amount of light used for observation can be set depending on the number of sets of protrusions. Further, regarding the arrangement and shape of each protrusion, the parameters such as the distances L ₁ , L ₂ , L ₃ and the radii r ₁ , r ₂ , r ₃ may be set to the same value, or mutually Different values may be set.

  FIG. 5A is a bottom view and FIG. 5B is a cross-sectional view taken along line III-III showing the configuration of another modification of the solid immersion lens. In the solid immersion lens 1D, rectangular protrusions 7a and 7b are provided on the bottom surface 3 as protrusions provided at positions sandwiching the central axis Ax. Thus, as for the shape of the protrusion, not only a circle but also various shapes such as an ellipse, a rectangle, or a polygon may be used.

6A is a bottom view illustrating the configuration of another reference example of the solid immersion lens, and FIG. 6B is a cross-sectional view taken along arrows IV-IV. In the solid immersion lens 1E, circular protrusions 8a and 8b are provided on the bottom surface 3 at positions sandwiching the central axis Ax. Moreover, the connection protrusion part 8c which includes the center part of the bottom face 3 and connects protrusion part 8a, 8b with respect to these protrusion parts 8a, 8b is provided. Even in such a configuration, the contact pattern of the bottom surface 3 with respect to the sample by the connected protrusions 8a, 8b, and 8c is axisymmetric with respect to the central axis Ax. Thus, in the structure which provides the protrusion part including the center part of an attachment surface, you may form the protrusion part so that the other protrusion part provided in the position on both sides of central axis Ax may be connected.

  Next, a semiconductor device inspection apparatus and inspection method using the solid immersion lens 1A according to the present embodiment will be described. Here, the solid immersion lens according to the present invention is generally applicable to a microscope and a sample observation method for observing a sample. In the following, a semiconductor inspection apparatus and inspection method in which a semiconductor device is an observation object (inspection object) will be described as an example.

  First, an inspection apparatus used for a semiconductor device inspection method will be described. FIG. 7 is a block diagram of a semiconductor inspection apparatus having a solid immersion lens according to the present embodiment. This semiconductor inspection device targets semiconductor devices formed on a semiconductor substrate, obtains images of circuit patterns made up of transistors, wirings, etc. on the semiconductor substrate, detects internal information, and inspects them I do.

  As shown in FIG. 7, the semiconductor inspection apparatus includes an observation unit A that observes the semiconductor device S, a control unit B that controls the operation of each unit of the observation unit A, and processes and instructions necessary for the inspection of the semiconductor device S. And an analysis unit C for performing the above. Further, the semiconductor device S to be inspected is placed on the stage 18 provided in the observation unit A.

  The observation unit A includes an image acquisition unit 13 installed in a dark box (not shown), an optical system 14, and a solid immersion lens 1A according to the present embodiment. The image acquisition unit 13 includes, for example, a photodetector and an imaging device, and is a unit that acquires an image of the semiconductor device S. An optical system 14 is provided between the image acquisition unit 13 and the semiconductor device S placed on the stage 18 to guide an image by light from the semiconductor device S to the image acquisition unit 13.

  The optical system 14 is provided with an objective lens 20 on which light from the semiconductor device S is incident at a predetermined position facing the semiconductor device S. Light emitted from, reflected by, or the like from the semiconductor device S enters the objective lens 20 and reaches the image acquisition unit 13 via the optical system 14 including the objective lens 20. Then, the image acquisition unit 13 acquires an image of the semiconductor device S used for inspection.

  The image acquisition unit 13 and the optical system 14 are integrally configured in a state where the optical axes coincide with each other. An XYZ stage 15 is installed for the image acquisition unit 13 and the optical system 14. Thereby, the image acquisition unit 13 and the optical system 14 are moved as necessary in each of the X direction, the Y direction (horizontal direction), and the Z direction (vertical direction) to perform alignment and focusing on the semiconductor device S. It has a possible configuration.

  An inspection unit 16 is provided for the semiconductor device S to be inspected. When inspecting the semiconductor device S, the inspection unit 16 performs state control of the semiconductor device S as necessary. The method for controlling the state of the semiconductor device S by the inspection unit 16 differs depending on the specific inspection method applied to the semiconductor device S. For example, a voltage is supplied to a predetermined portion of a circuit pattern formed in the semiconductor device S. A method or a method of irradiating the semiconductor device S with a laser beam as probe light is used.

  Further, the observation unit A is further provided with a solid immersion lens 1A. In the semiconductor inspection apparatus, the solid immersion lens 1 </ b> A is installed so as to be movable with respect to the image acquisition unit 13 and the optical system 14 and the semiconductor device S placed on the stage 18. Specifically, the solid immersion lens 1 </ b> A includes the optical axis from the semiconductor device S to the objective lens 20, and is out of the optical axis and the insertion position installed in close contact with the surface of the semiconductor device S as described above. It is configured to be movable between positions (standby positions).

  Further, a solid immersion lens driving unit 30 is provided for the solid immersion lens 1A. The solid immersion lens drive unit 30 is a drive unit that drives the solid immersion lens 1A to move between the insertion position and the standby position. The solid immersion lens drive unit 30 adjusts the insertion position of the solid immersion lens 1A with respect to the objective lens 20 of the optical system 14 by minutely moving the position of the solid immersion lens 1A. In FIG. 1, the solid immersion lens 1 </ b> A is shown in a state of being installed at an insertion position between the objective lens 20 and the semiconductor device S.

  A control unit B and an analysis unit C are provided for the observation unit A that performs observation for inspecting the semiconductor device S.

  The control unit B includes an observation control unit 51, a stage control unit 52, and a solid immersion lens control unit 53. The observation control unit 51 controls the execution of the observation of the semiconductor device S performed in the observation unit A and the setting of observation conditions by controlling the operations of the image acquisition unit 13 and the inspection unit 16.

  The stage control unit 52 controls the operation of the XYZ stage 15 to set the observation location of the semiconductor device S by the image acquisition unit 13 and the optical system 14 as the inspection location in the present inspection apparatus, or the alignment and focusing thereof. To control. Further, the solid immersion lens control unit 53 controls the operation of the solid immersion lens driving unit 30, thereby moving the solid immersion lens 1A between the insertion position and the standby position or adjusting the insertion position of the solid immersion lens 1A. Control etc.

  The analysis unit C includes an image analysis unit 61 and an instruction unit 62. The image analysis unit 61 performs necessary analysis processing on the image acquired by the image acquisition unit 13. Further, the instruction unit 62 refers to the input content from the operator, the analysis content in the image analysis unit 61, and the like, and necessary instructions regarding the execution of the inspection of the semiconductor device S in the observation unit A via the control unit B. I do.

  In particular, in this embodiment, the analysis unit C inspects the semiconductor device S using the solid immersion lens in response to the solid immersion lens 1A and the solid immersion lens driving unit 30 being installed in the observation unit A. Necessary processing and instructions regarding

  That is, when the solid immersion lens 1A is inserted between the objective lens 20 and the semiconductor device S, in the observation unit A, the image acquisition unit 13 reflects from the solid immersion lens 1A with the solid immersion lens 1A in the insertion position. Acquire an image containing light. In the analysis unit C, the image analysis unit 61 performs a predetermined analysis such as obtaining the barycentric position of the reflected light image of the image including the reflected light from the solid immersion lens 1A acquired by the image acquisition unit 13. . The instruction unit 62 refers to the image including the reflected light from the solid immersion lens 1 </ b> A analyzed by the image analysis unit 61, and the position of the center of gravity of the reflected light image with respect to the solid immersion lens control unit 53 is the semiconductor device S. It is instructed to adjust the insertion position of the solid immersion lens 1 </ b> A so as to coincide with the inspection location.

  Next, a semiconductor device inspection method (sample observation method) according to this embodiment will be described.

  First, the semiconductor device S to be inspected is observed with the solid immersion lens 1A installed at the standby position. Here, the pattern image of the circuit pattern that is the observation image of the semiconductor device S is acquired by the image acquisition unit 13 via the optical system 14 including the objective lens 20. Further, the inspection unit 16 controls the state of the semiconductor device S to a predetermined state and acquires an abnormal observation image for detecting an abnormal portion of the semiconductor device S.

  Next, it is checked whether or not there is an abnormal portion in the semiconductor device S using the pattern image and the abnormality observation image acquired by the image acquisition unit 13. If there is an abnormal part, the position is detected, and the detected abnormal part is set as an inspection part (observation part by a microscope) by the semiconductor inspection apparatus. Then, the image acquisition unit 13 and the optical system 14 are moved by the XYZ stage 15 so that the set inspection location is positioned at the center of the image acquired by the image acquisition unit 13.

  Subsequently, the solid immersion lens 1 </ b> A is installed at an inspection location determined to be an abnormal location in the semiconductor device S, and the solid immersion lens 1 </ b> A is inserted between the semiconductor device S and the objective lens 20. In addition, before the solid immersion lens 1A is installed, the optical contact liquid is dropped on the inspection location to wet the inspection location of the semiconductor device S. This optical contact liquid consists of water containing amphiphilic molecules. Since the optical contact liquid contains amphiphilic molecules, the surface tension on the semiconductor substrate, which is a hydrophobic surface, is reduced. As a result, the wettability on the hydrophobic surface is improved and the optical contact liquid spreads on the semiconductor device S.

  As the amphiphilic molecule used here, a surfactant molecule is preferably used. As the surfactant molecule, an ionic surfactant molecule and a nonionic surfactant molecule can also be used. As the ionic surfactant, any of a cationic surfactant, an anionic surfactant, and an amphoteric surfactant can be used.

  Surfactants are usually used in various applications as wetting agents, penetrants, foaming agents, antifoaming agents, emulsifiers, antistatic agents, etc., but in the present invention, in addition to those having wettability related to wettability, Those having antifoaming properties for suppressing bubbles and antistatic properties for suppressing charging are suitable. By using a surfactant having an antistatic function, it is possible to prevent entrapment of air due to charging. Further, by using a surfactant having antifoaming properties, it is possible to prevent generation of bubbles due to mechanical conveyance or stirring when supplying the optical contact liquid.

  Moreover, it is preferable that the optimum concentration range of the surfactant is greater than 0 times and not more than 400 times the critical micelle concentration of the surfactant. If it is larger than 400 times, the viscosity of the optical contact liquid tends to increase too much, which may hinder optical coupling. A more preferable range is 0.5 to 100 times the critical micelle concentration of the surfactant. If it is less than 0.5 times, the surface tension of the optical contact liquid tends not to be lowered sufficiently, and if it exceeds 100 times, the viscosity of the optical contact liquid tends to increase too much. For the same reason, a more preferable range is a range of 1 to 10 times the critical micelle concentration of the surfactant.

  The optical contact liquid used in the present embodiment is not limited to those containing surfactant molecules, and includes hydrophilic groups (carboxyl group, sulfo group, quaternary ammonium group, hydroxyl group, etc.) and hydrophobic groups ( It may be a molecule having both a lipophilic group and a long-chain hydrocarbon group. For example, humectants such as glycerin, propylene glycol and sorbitol, phospholipids, glycolipids, amino lipids and the like can be mentioned.

  In a state where the semiconductor substrate and the solid immersion lens are optically bonded using the optical contact liquid, van der Waals force is generated between the hydrophilic group of the amphiphilic molecule physically adsorbed on the semiconductor substrate and the water molecule. It is thought that the volatilization stops when the water molecules are restrained. At this time, the distance between the solid immersion lens and the semiconductor substrate can be, for example, λ / 20 (λ: irradiation wavelength) or less. As a result, the optical contact between the solid immersion lens and the semiconductor substrate is further improved. Fixation is achieved. Here, “optical contact” means a state in which evanescent coupling is realized between the semiconductor substrate and the solid immersion lens.

  Further, as an optical coupling material other than the optical contact liquid, for example, a refractive index matching fluid (index matching liquid or the like) for refractive index matching between a solid immersion lens and a semiconductor substrate as described in Japanese Patent Publication No. 7-18806. Can be mentioned. Note that the refractive index matching fluid and the optical contact liquid are different, and the former realizes a high NA through the refractive index of the fluid. On the other hand, the latter realizes a high NA by the role of the optical contact liquid to assist the evanescent coupling. Here, an embodiment using the optical contact liquid will be described in detail, but the same effect can be obtained even in a form using a refractive index matching fluid. However, in that case, since it is not always necessary to dry the fluid, a step of blowing air for promoting drying, which will be described later, may be omitted.

  When the optical contact liquid spreads around the inspection location on the semiconductor substrate, the solid immersion lens 1A is moved from the standby position before the optical contact liquid is dried, and is inserted between the semiconductor device S and the objective lens 20 and inserted. Adjust the position.

  Here, since the optical contact liquid contains amphiphilic molecules, as described above, wettability can be imparted to the substrate surface of the semiconductor device S and the mounting surface of the solid immersion lens 1A. Further, when the solid immersion lens 1A is installed at a predetermined position, the weight of the solid immersion lens 1A is used. Therefore, the minute solid immersion lens 1A can be easily installed at a desired position on the surface of the semiconductor substrate without applying excessive pressure. First, the image acquisition unit 13 acquires an image including the reflected light from the solid immersion lens 1A. Adjustment of the insertion position of the solid immersion lens 1A is performed using reflected light from the respective reflecting surfaces of the solid immersion lens 1A in the reflected light image included in this image as a guide.

  In adjusting the insertion position of the solid immersion lens 1A, the image analysis unit 61 analyzes the image including the reflected light from the solid immersion lens 1A automatically or based on an instruction from the operator, The position of the center of gravity of the reflected light image is obtained. Further, in the instruction unit 62, the center of gravity position of the reflected light image obtained by the image analysis unit 61 is the semiconductor device S with respect to the solid immersion lens 1 </ b> A and the solid immersion lens driving unit 30 via the solid immersion lens control unit 53. The adjustment of the insertion position of the solid immersion lens 1 </ b> A is instructed so as to coincide with the inspection location. Thereby, the alignment of the solid immersion lens 1A with respect to the semiconductor device S and the objective lens 20 is performed.

  Further, the instruction unit 62 adjusts the insertion position of the solid immersion lens 1A as described above, and the semiconductor device S in which the solid immersion lens 1A is installed in close contact with the XYZ stage 15 via the stage control unit 52. And the adjustment of the distance from the objective lens 20 of the optical system 5 is instructed. By this adjustment, focusing is performed in a state where the solid immersion lens 1A is inserted.

  Thereafter, air is blown onto the solid immersion lens 1A to evaporate and dry the optical contact liquid, and the solid immersion lens 1A and the semiconductor substrate S are optically brought into close contact with each other. By spraying air, the optical contact liquid can be evaporated more quickly.

  Here, when a solid immersion lens having a flat bottom surface (hereinafter referred to as a “plano-convex lens”) is used, the optical contact liquid is sandwiched between the solid immersion lens and the semiconductor device and is laterally moved. However, there is no open surface that contributes to evaporation, and evaporation takes time. On the other hand, since the solid immersion lens 1A according to the present embodiment is in contact with the semiconductor substrate only at the protruding portions 4a and 4b of the bottom surface portion 3, the optical contact liquid can evaporate over a wide range. it can. For this reason, evaporation can be completed in a short time, and the solid immersion lens 1A and the semiconductor device S can be quickly adhered and fixed.

  By evaporating the optical contact liquid in this way, for the solid immersion lens 1A, optical contact and physical fixation are realized in the semiconductor device S and the two protrusions 4a and 4b. Moreover, when acquiring an observation image, the light from the semiconductor device S passes through the optical contact portion between the semiconductor device S and the solid immersion lens 1A. Since the contact pattern of the protrusions 4a and 4b with respect to the semiconductor device S is axisymmetric with respect to the central axis of the lens, a light flux having a numerical aperture NA corresponding to the position of the protrusions 4a and 4b is obtained.

  Further, in the case of a bi-convex lens formed so that the bottom surface portion is in contact with the semiconductor substrate at one point, the solid immersion lens may be inclined and installed on the semiconductor substrate. The parts are not optically coupled, and the solid immersion lens is displaced from the position where it should originally be installed. On the other hand, since the solid immersion lens 1A according to the present embodiment has a plurality of protrusions on the bottom surface portion 3, the solid immersion lens 1A is not placed in an inclined state and deviates from the position where it should be originally installed. It is installed without. Furthermore, positioning becomes easy.

  When the solid immersion lens 1A is optically brought into close contact with the semiconductor device S in this way, an enlarged observation image of the semiconductor substrate is acquired through an optical system including the solid immersion lens 1A. The observation image is acquired when light from the semiconductor device S is guided to the image acquisition unit 13. Moreover, when acquiring an observation image, the light from the semiconductor device S passes through the optical contact portion between the semiconductor device S and the solid immersion lens 1A.

  When the observation image is acquired in this way, the enlarged observation image is acquired, and then the solid immersion lens 1A and the semiconductor device S are peeled off. At that time, a solvent of the optical contact liquid (hereinafter referred to as “solvent”) is dropped around the position where the solid immersion lens 1A on the semiconductor device S is attached to wet the attachment position of the solid immersion lens 1A. By dropping the solvent, the solvent enters between the semiconductor device S and the solid immersion lens 1A, and the optical coupling and physical fixation between the semiconductor device S and the solid immersion lens 1A are released.

  The bottom surface portion 3 of the solid immersion lens 1 </ b> A is formed so as to have a plurality of protruding portions, and has an open surface between the semiconductor device S and the solid immersion lens 1 </ b> A. Therefore, the solvent can be rapidly penetrated, and the solid immersion lens 1A and the semiconductor device S can be separated in a short time. In addition, the solvent is dropped here, but the optical contact liquid may be dropped. Further, when the region to be fixed is narrowed, the fixing strength is weakened, and depending on the degree of narrowing, it is possible to carry out without using a liquid when peeling the adhesion.

  Thereafter, the solid immersion lens 1A is moved to another inspection location or a standby position, and the inspection of the inspection location is completed.

  Subsequently, an effect obtained by using the solid immersion lens according to the present embodiment will be described.

  The solid immersion lens 1A has a plurality of protrusions 4a and 4b, and contacts the semiconductor device S which is a sample in these protrusions 4a and 4b. For this reason, it is possible to obtain a light flux passing through a desired optical path. Further, by bringing the solid immersion lens 1A into contact with the semiconductor device S through the plurality of protrusions 4a and 4b, the solid immersion lens 1A can be stably installed on the semiconductor device S without being inclined, and position control is facilitated. Furthermore, the possibility that the sticking is prevented by dust is lower than that of the plano-convex lens. Further, since the force required to separate the solid immersion lens 1A and the sample is extremely weak, there is no possibility of damaging the semiconductor device S and the solid immersion lens 1A, and the solid immersion lens 1A can be used repeatedly. .

  Further, since the solid immersion lens 1A comes into contact with the semiconductor device S at the two protrusions 4a and 4b, the optical contact liquid can be evaporated or the solvent can penetrate more quickly than the plano-convex lens. For this reason, the solid immersion lens 1 </ b> A can be optically adhered to the semiconductor device S or peeled off from the semiconductor device S in a short time.

  Although the solid immersion lens 1A shown in FIG. 1 is used here, other solid immersion lenses according to the present invention, such as the solid immersion lenses 1B to 1E, may be used.

  In the above embodiment, the amphiphilic molecule is included in the optical contact liquid between the semiconductor device S and the solid immersion lens 1A. Instead, the solid immersion lens 1A is attached to the semiconductor device S. A hydrophilic treatment can be applied to the surface.

  The reason why the wettability is improved when the optical contact liquid contains amphiphilic molecules is that hydrophilic groups adhere to the hydrophobic surface. Therefore, even when the optical contact liquid does not contain amphiphilic molecules, the mounting surface of the solid immersion lens 1A with the semiconductor device S and the mounting surface of the semiconductor device S with the solid immersion lens 1A are hydrophobic. Even so, wettability can be improved by applying a hydrophilic treatment for attaching a hydrophilic group to one or both of these surfaces. In addition, when the surface of the semiconductor device S is originally hydrophilic, wettability can be ensured even if the surface is not subjected to hydrophilic treatment.

  In this manner, by imparting wettability to one or both of the solid immersion lens 1A and the mounting surface of the semiconductor device S, as in the case of using the optical contact liquid containing amphiphilic molecules, the semiconductor device S on the substrate is provided. The optical contact liquid can be accurately retained at a desired inspection location. Further, the optical adhesion between the semiconductor device S and the solid immersion lens 1A can be ensured without applying excessive pressure.

  As a method for subjecting the solid immersion lens 1A and the semiconductor device S to hydrophilic treatment, there is a method in which hydrophilic groups are physically adsorbed and temporarily attached. As a specific method for physically adsorbing the hydrophilic group, there is a method in which an aqueous solution of a surfactant, an amphiphilic molecule such as an amino acid or protein is applied to the surface to be subjected to a hydrophilic treatment, and dried.

  In addition, as a method of performing the hydrophilic treatment, there is a method of performing surface modification by chemically adsorbing a hydrophilic group. Methods for chemically adsorbing hydrophilic groups include a method of irradiating UV (ultraviolet) light, a method using a wet process (for example, applying a solution in which sulfuric acid, hydrogen peroxide and water are added), and a method using a dry process ( For example, there is a method of irradiating an ion beam. As an example, Semico Clean 23 (manufactured by Furuuchi Chemical Co., Ltd.) can be used in the hydrophilic treatment by chemical adsorption in a wet process.

  In addition, as another method for performing the hydrophilic treatment, a coating method can also be used. In this case, it is preferable to coat hydrophilic nanoparticles or the like on the surface. For example, the wettability can be improved by coating silica nanoparticles on one or both of the solid immersion lens and the semiconductor substrate. Examples of such nanoparticles include GLANZOX 3900 (manufactured by Fujimi Incorporated), a dew condensation water droplet inhibitor (manufactured by TOTO), and the like.

  In addition to silica nanoparticles, titanium oxide nanoparticles may be coated. It should be noted that when the hydrophilic treatment is performed by coating as described above, it is considered that the evanescent coupling of light cannot be obtained if the coating film is too thick. For this reason, it is preferable that a coating film shall be 200 nm or less, for example.

  When the solid immersion lens or the substrate surface is subjected to a hydrophilic treatment, water molecules in the atmosphere are always adsorbed to these hydrophilic groups, so that a water film is formed. In this state, when the solid immersion lens 1A and the substrate S are sufficiently brought close to each other, an attractive force due to hydrogen bonding acts between water molecules, and the solid immersion lens 1A and the substrate S are brought into close contact with each other.

  When the solid immersion lens and the substrate surface are sufficiently hydrophilically treated and the surface accuracy is sufficiently good, adhesion can be realized by simply superimposing these surfaces. Here, the distance at which the attractive force due to hydrogen bonding works is as short as several nanometers. For this reason, when the hydrophilic treatment of the solid immersion lens or the substrate surface is insufficient, or when the surface accuracy is insufficient, it is considered that sufficient adhesion cannot be obtained between the surfaces.

  In such a case, it is preferable to use an optical contact liquid for assisting the contact. Here, a case where the main component of the optical contact liquid is water is considered. In this case, when the interface between the solid immersion lens and the substrate is filled with the optical contact liquid, they are connected via hydrogen bonds of hydroxyl groups and water molecules. However, in this state, since the distance between the solid immersion lens 1A and the substrate S is wide, the contact is not yet achieved. Thereafter, in the process where excess water is volatilized, an attractive force acts between the solid immersion lens and the substrate by hydrogen bonding. Thereby, the space | interval of an interface narrows gradually with volatilization of a liquid, and volatilization of an optical contact | adherence liquid will stop when it will be in the contact | adherence state.

  In addition, when the solid immersion lens and the substrate are not subjected to a hydrophilic treatment and no surfactant is added to the optical contact liquid, hydrogen bonding works between the solid immersion lens and the substrate and water molecules. Absent. For this reason, in the process of volatilization of water, the solid immersion lens and the substrate and the water molecules are separated and air flows in, and adhesion is not realized.

  On the other hand, even when the solid immersion lens and the substrate are not subjected to hydrophilic treatment in advance, if the surfactant is added to the optical contact liquid, the optical contact liquid is inserted between the solid immersion lens and the substrate. Further, the surfactant, that is, the hydrophilic group is physically adsorbed on the solid immersion lens and the substrate. Thereby, it will be in the same state as when they were hydrophilically treated in advance, and the close contact is realized.

  As mentioned above, although the suitable example of this invention was demonstrated, this invention is not limited to the said embodiment. For example, in the above embodiment, an operator drops an optical contact liquid containing amphiphilic molecules, but an optical contact droplet dropping device (an optical binding material supply device for supplying an optical binding material) is provided. It can also be set as the aspect provided separately. Moreover, it can also be set as the aspect which provides the air spraying apparatus for drying an optical contact | adherence liquid, a water absorbing sheet pressing apparatus, etc. Furthermore, as means for wetting the semiconductor device, various aspects such as an aspect in which the optical contact liquid is dropped, an aspect in which the optical contact liquid is thinly applied, an aspect in which the optical contact liquid is sprayed, and an aspect in which the liquid is moistened with steam can be employed. In this case, since the optical contact liquid is quickly dried, the work for promoting the drying can be omitted.

  In addition to the semiconductor inspection apparatus shown in the above embodiment, the solid immersion lens of the present invention is also used when performing inspection using an emission microscope, OBIRCH analysis apparatus, time-resolved emission microscope, heat ray image analysis apparatus, etc. using a high-sensitivity camera. Can be used. In general, a microscope using the solid immersion lens described above is a microscope for observing an observation object, and includes an optical system that includes an objective lens on which light from the observation object is incident and guides an image of the observation object. The solid immersion lens having the above-described configuration may be provided. Further, as described above, an image acquisition unit that acquires an image of the observation object (sample) guided by the optical system may be provided for the optical system and the solid immersion lens.

  The solid immersion lens according to the present invention will be further described. In the following embodiments, the configuration of a plurality of protrusions provided mainly on the bottom surface will be described.However, the cross-sectional structure of each protrusion, the overall shape of the solid immersion lens, the propagation of light through the protrusion, A sample observation method using a solid immersion lens, or application to a microscope, a semiconductor inspection apparatus, an inspection method, and the like are the same as those in the first embodiment shown in FIG.

  FIG. 8A is a bottom view and FIG. 8B is a cross-sectional view taken along the line VV showing the configuration of the second embodiment of the solid immersion lens according to the present invention. The configuration of the solid immersion lens 41 of the present embodiment is the same as that of the solid immersion lens 1A of the first embodiment, but the configuration of the plurality of protrusions provided on the bottom surface serving as the mounting surface for the sample is different. .

  In the solid immersion lens 41, the bottom surface 3 serving as a mounting surface for the sample has a plurality of protrusions. That is, in the configuration shown in FIG. 8, a plurality of projecting portions 71 projecting downward are provided in a two-dimensional array over the entire bottom surface 3. Further, these protrusions 71 are formed so that the installation pattern of the protrusions 71 and the contact pattern with respect to the sample are symmetrical with respect to the central axis Ax.

Specifically, as shown in FIG. 8A, the protrusions 71 on the bottom surface 3 are arranged in the x-axis direction and the y-axis direction, and the arrangement intervals are constant in the x-axis direction and the y-axis direction, respectively. d _x, they are arranged in a two-dimensional matrix in _{d y.} In the configuration example shown in FIG. 8A, there are 7 columns in the y-axis direction, 4 in the first column from the negative side of the y-axis, 6 in the second column, 8 in the third column, and the central column. A total of 44 protrusions 71 are provided, with 8 in the 4th row, 8 in the 5th row, 6 in the 6th row and 4 in the 7th row. Each of the protrusions 71 is formed in a circular shape having a radius r.

  In such a configuration, among the 44 projecting portions 71, the two projecting portions located on the opposite side across the central axis Ax constitute an axially symmetric set, and 22 axially symmetric projecting portions. An installation pattern of the projecting portions 71 that is axisymmetric with respect to the central axis Ax as a whole is configured by the set of portions.

  The effect of the solid immersion lens 41 according to the present embodiment will be described.

  The solid immersion lens 41 has a plurality of protrusions 71, and these protrusions 71 are in contact with the sample. For this reason, it is possible to obtain a light flux passing through a desired optical path. In addition, by bringing the solid immersion lens 41 into contact with the sample via the plurality of protrusions 71, the solid immersion lens 41 can be stably placed on the sample without tilting, and position control becomes easy. In addition, the possibility of sticking being prevented by dust is lower than that of a plano-convex lens. In addition, since the force required to separate the solid immersion lens 41 and the sample is extremely weak, there is no possibility of damaging the solid immersion lens 41 and the like, and the solid immersion lens 41 can be used repeatedly.

  Further, the solid immersion lens 41 can be used in the same semiconductor inspection apparatus as described in the first embodiment, and inspection can be performed by the same method. Since the solid immersion lens 41 comes into contact with the semiconductor device at the protruding portion 71, the optical contact liquid can be evaporated or the solvent can permeate faster than the plano-convex lens. For this reason, the solid immersion lens 41 can be optically adhered to the semiconductor device in a short time or can be peeled off from the semiconductor device. Such an effect can be similarly obtained for samples other than semiconductor devices.

  In the above-described embodiment, the plurality of protrusions 71 are arranged in a two-dimensional matrix with respect to the protrusions 71 that are axisymmetric with respect to the central axis Ax. At this time, since the projecting portion 71 in contact with the sample is uniformly arranged over the entire bottom surface 3 of the solid immersion lens 41, the observation is preferably performed with a sufficiently high numerical aperture NA with respect to the observation position of the sample. Can be done. Further, as described above, since the protruding portions are uniformly arranged over the entire surface, excellent operability can be obtained. Furthermore, in such a configuration, the observation conditions of the sample using the solid immersion lens, such as the numerical aperture NA and the light amount, are appropriately set according to the arrangement interval of the two-dimensional matrix projections, the shape of each projection, and the like. Can do. In addition, about the specific arrangement | sequence structure of a protrusion part, various structures may be used and the structure which arrange | positions several protrusion part in a one-dimensional form may be used.

  FIG. 9A is a bottom view and FIG. 9B is a sectional view taken along the line VI-VI showing the configuration of the third embodiment of the solid immersion lens according to the present invention. The configuration of the solid immersion lens 42 of the present embodiment is the same as that of the solid immersion lens 1A of the first embodiment, but the configuration of the plurality of protrusions provided on the bottom surface serving as the mounting surface for the sample is different. .

  In the solid immersion lens 42, the bottom surface 3 serving as a mounting surface for the sample has a plurality of protrusions. That is, in the configuration shown in FIG. 9, a plurality of projecting portions 72 projecting downward are provided radially over the entire bottom surface 3. Further, these protrusions 72 are formed so that the installation pattern of the protrusions 72 and the contact pattern with respect to the sample are symmetrical with respect to the central axis Ax.

Specifically, the protrusions 72 on the bottom surface 3 are each formed in a fan shape with an opening angle θ ₁ , each protrusion extending radially from the center O of the bottom surface 3 as shown in FIG. in the angular interval theta ₂ is provided over the entire bottom surface 3. In the configuration example shown in FIG. 9A, two protrusions are arranged with the center axis Ax sandwiched so that the center line matches the y axis, and the center axis Ax is set so that the center line matches the x axis. Two protrusions arranged on both sides, two protrusions arranged on both sides of the central axis Ax so that the center line coincides with a straight line that forms 45 degrees with the x axis, and forms −45 degrees with the x axis. There are two protrusions arranged with the central axis Ax sandwiched so that the straight line and the center line coincide with each other, and a total of eight protrusions 72 are provided at an angular interval θ ₂ = 45 degrees. Each protrusion is formed in a shape lacking a fan-shaped point, that is, a portion near the center O of the bottom surface 3.

  In such a configuration, among the eight protrusions 72, the two protrusions located on the opposite side across the central axis Ax are each configured as an axisymmetric set, and the four axisymmetric protrusions An installation pattern of the projecting portions 72 that is axisymmetric with respect to the central axis Ax as a whole is configured by the set of portions. In addition, each protruding portion is formed in a fan shape lacking its tip portion, that is, a portion near the center O of the bottom surface 3, but may have a shape in which the tip portion is not missing.

  The effect of the solid immersion lens 42 according to the present embodiment will be described.

  The solid immersion lens 42 has a plurality of protrusions 72, and the protrusions 72 come into contact with the sample. For this reason, it is possible to obtain a light flux passing through a desired optical path. Further, by bringing the solid immersion lens 42 into contact with the sample via the plurality of protrusions 72, the solid immersion lens 42 can be stably placed on the sample without tilting, and position control becomes easy. Furthermore, the possibility that the sticking is prevented by dust is lower than that of the plano-convex lens. In addition, since the force required to separate the solid immersion lens 42 and the sample is extremely weak, there is no possibility of damaging the solid immersion lens 42 and the like, and the solid immersion lens 42 can be used repeatedly.

  Further, the solid immersion lens 42 can be used in the same semiconductor inspection apparatus as described in the first embodiment, and the inspection can be performed by the same method. Since the solid immersion lens 42 comes into contact with the semiconductor device at the protruding portion 72, the optical contact liquid can be evaporated or the solvent can permeate faster than the plano-convex lens. For this reason, the solid immersion lens 42 can be optically adhered to the semiconductor device in a short time or can be peeled off from the semiconductor device. Such an effect can be similarly obtained for samples other than semiconductor devices.

  In the above-described embodiment, the plurality of projecting portions 72 that are axially symmetric with respect to the central axis Ax are arranged radially. At this time, since the protrusions 72 that come into contact with the sample are uniformly arranged in the radial direction of the bottom surface 3 of the solid immersion lens 42, the observation is preferably performed with a sufficiently high numerical aperture NA with respect to the observation position of the sample. Can be performed. Moreover, since the protrusions are uniformly arranged in the radial direction as described above, excellent operability can be obtained. Further, in such a configuration, the observation conditions of the sample using the solid immersion lens, such as the numerical aperture and the light amount, can be appropriately set according to the opening angle of the fan-shaped protrusions, the angular interval between the protrusions, and the like. . Various configurations may be used for the specific shape and arrangement of the protrusions.

Figure 10 is a fourth illustrating a reference example of the configuration of the embodiment (a) a bottom view, and (b) VII-VII arrow sectional view of the solid immersion lens. The configuration of the solid immersion lens 43 of the present embodiment is the same as that of the solid immersion lens 1A of the first embodiment, but the configuration of the plurality of protrusions provided on the bottom surface serving as the mounting surface for the sample is different. .

  In the solid immersion lens 43, the bottom surface 3 serving as a mounting surface for the sample has a plurality of protrusions. That is, in the configuration shown in FIG. 10, a plurality of rail-like projecting portions 73 that project downward are arranged over the entire bottom surface 3. Further, these protrusions 73 are formed so that the installation pattern of the protrusions 73 and the contact pattern with respect to the sample are symmetrical with respect to the central axis Ax.

Specifically, as shown in FIG. 10A, the protrusions 73 on the bottom surface 3 have a rail-like shape whose longitudinal direction is the y-axis direction, and a constant arrangement interval L in the x-axis direction. ₂ are arranged. The width of each protrusion is constant in _{L 1,} the ratio _L 1 / _{L 2} of the width of the projecting portions _{L 1} and arrangement interval _{L 2} is also constant. In the configuration example shown in FIG. 10A, the projecting portions constituting the central row are arranged on the y-axis. Furthermore, four on each of the + x direction and the -x direction from the central row are arranged at regular arrangement interval L ₂ in parallel with the y-axis, it is provided a total of nine protrusions 73. Moreover, about the longitudinal direction of each protrusion part, it is preferable to form in the rail shape extended to the vicinity of the edge of the periphery of the bottom face 3 so that a protrusion part may be provided over the whole surface of the bottom face 3. Alternatively, the length of each protrusion 73 can be appropriately set according to a desired numerical aperture NA or the like.

  In such a configuration, among the nine protrusions 73, the center row is arranged so that the center of the rail shape coincides with the center O of the bottom surface 3, and the other eight protrusions have the center axis Ax. A pair of axially symmetric protrusions is formed from two protrusions located on the opposite side of the pair, and a group of four axially symmetric protrusions is formed. An installation pattern of the projecting portions 73 that is axially symmetric with respect to the central axis Ax as a whole is constituted by the central row and these four sets.

  The effect of the solid immersion lens 43 according to the present embodiment will be described.

  The solid immersion lens 43 has a plurality of protrusions 73 and contacts the sample at these protrusions 73. For this reason, it is possible to obtain a light flux passing through a desired optical path. In addition, by bringing the solid immersion lens 43 into contact with the sample via the plurality of protrusions 73, the solid immersion lens 43 can be stably placed on the sample without tilting, and position control becomes easy. In addition, the possibility of sticking being prevented by dust is lower than that of a plano-convex lens. Further, since the force required to separate the solid immersion lens 43 and the sample is extremely weak, there is no possibility of damaging the solid immersion lens 43 and the like, and the solid immersion lens 43 can be used repeatedly.

  Further, the solid immersion lens 43 can be used in the same semiconductor inspection apparatus as described in the first embodiment, and the inspection can be performed by the same method. Since the solid immersion lens 43 comes into contact with the semiconductor device at the protruding portion 73, the optical contact liquid can be evaporated or the solvent can permeate faster than the plano-convex lens. For this reason, the solid immersion lens 43 can be optically adhered to the semiconductor device in a short time or can be peeled off from the semiconductor device. Such an effect can be similarly obtained for samples other than semiconductor devices.

  Further, when the solvent is dropped to peel the solid immersion lens 43 from the semiconductor device, it is considered that the lens bottom is blocked and the lens bottom cannot be wet directly. Even in such a case, as long as the bottom surface 3 of the solid immersion lens 43 is configured, as shown in FIG. 11, the solvent 90 is blown by the wind along the y-axis direction in the drawing. By sending it between the two, the penetration of the solvent can be accelerated and peeling can be easily performed.

  Furthermore, in the said embodiment, it is set as the structure which the rail-shaped protrusion part 73 arranges in a predetermined direction at fixed intervals so that it may become axially symmetrical with respect to the central axis Ax. At this time, since the projecting portion 73 in contact with the sample is uniformly arranged over the entire bottom surface 3 of the solid immersion lens 43, observation is preferably performed with a sufficiently high numerical aperture NA with respect to the observation position of the sample. Can be done. Further, as described above, since the protruding portions are uniformly arranged over the entire surface, excellent operability can be obtained. Furthermore, in such a configuration, the observation conditions of the sample using the solid immersion lens, such as the numerical aperture and the amount of light, can be set as appropriate depending on the ratio of the arrangement interval of the rail-shaped protrusions and the width of each rail. it can. Various configurations may be used for the specific shape and arrangement of the protrusions.

  12A is a bottom view and FIG. 12B is a cross-sectional view taken along the line VIII-VIII showing the configuration of the fifth embodiment of the solid immersion lens according to the present invention. The configuration of the solid immersion lens 44 of the present embodiment is the same as that of the solid immersion lens 1A of the first embodiment, but the configuration of the plurality of protrusions provided on the bottom surface serving as the mounting surface for the sample is different. .

  In the solid immersion lens 44, the bottom surface 3 serving as a mounting surface for the sample has a plurality of protrusions. That is, in the configuration shown in FIG. 12, a plurality of projecting portions 74a and 74b having a ring shape projecting downward are provided concentrically. In addition, these protrusions 74a and 74b are formed so that the installation pattern of the protrusions 74a and 74b and the resulting contact pattern with respect to the sample are axisymmetric with respect to the central axis Ax.

Specifically, as shown in FIG. 12A, two ring-shaped projecting portions 74 a and 74 b are formed on the bottom surface 3. The shape of the protrusion 74a is a ring shape having an inner diameter r ₁ and an outer diameter r ₂ centered on the ball center O (r ₁ <r ₂ ). The radii r ₁ and r ₂ are set, for example, so as to correspond to light beams having numerical apertures NA of 1.2 and 1.4, respectively. On the other hand, the protrusion 74b is formed in a ring shape having an inner diameter r ₃ and an outer diameter r ₄ with the ball center O as the center (r ₂ <r ₃ , r ₃ <r ₄ ). The radii r ₃ and r ₄ are set, for example, so as to correspond to light beams having numerical apertures NA of 2.2 and 2.4, respectively. Note that r ₁ to r ₄ may be set in accordance with a light flux having an NA value different from the numerical aperture NA.

  In such a configuration, each of the two protruding portions 74a and 74b is configured to be axially symmetric with respect to the central axis Ax. Therefore, an installation pattern of the projecting portions 74a and 74b that are axisymmetric with respect to the central axis Ax as a whole is configured.

  Moreover, in this embodiment, the groove | channel which connects the inner side and the outer side of a ring-shaped protrusion part is provided in each of the protrusion parts 74a and 74b. That is, in FIG. 12A, the protrusion 74a is provided with a groove 75a on both the + y side and the −y side so as to cross the protrusion 74a along the y axis. Also in the protrusion 74b, a groove 75b is provided on both the + y side and the −y side so as to cross the protrusion 74b along the y axis. For this reason, even if the grooves 75a and 75b are provided, the contact pattern of the bottom surface 3 with respect to the sample by the protrusions 74a and 74b is axisymmetric with respect to the center axis Ax of the lens.

  The effect of the solid immersion lens 44 according to the present embodiment will be described.

  The solid immersion lens 44 has a plurality of protrusions 74a and 74b, and contacts the sample at these protrusions 74a and 74b. For this reason, it is possible to obtain a light flux passing through a desired optical path. Further, by bringing the solid immersion lens 44 into contact with the sample via the plurality of protrusions 74a and 74b, the solid immersion lens 44 can be stably placed on the sample without tilting, and position control becomes easy. In addition, the possibility of sticking being prevented by dust is lower than that of a plano-convex lens. Further, since the force required to separate the solid immersion lens 44 and the sample is extremely weak, there is no possibility of damaging the solid immersion lens 44 and the like, and the solid immersion lens 44 can be used repeatedly.

  Further, the solid immersion lens 44 can be used in the same semiconductor inspection apparatus as described in the first embodiment, and the inspection can be performed by the same method. Since the solid immersion lens 44 comes into contact with the semiconductor device at the protrusions 74a and 74b, the optical contact liquid can be evaporated or the solvent can be permeated faster than the plano-convex lens. For this reason, the solid immersion lens 44 can be optically adhered to the semiconductor device in a short time or can be peeled off from the semiconductor device. Such an effect can be similarly obtained for samples other than semiconductor devices.

  In the above-described embodiment, the ring-shaped protrusions 74a and 74b that are symmetric with respect to the central axis Ax are arranged concentrically. Therefore, the inner diameter of each ring shape can be set in accordance with the lower limit of the numerical aperture NA of the light beam desired to pass through the protrusion, and the outer diameter can be set in accordance with the upper limit of the numerical aperture NA of the light beam desired to pass. . Thereby, it is possible to selectively pass only a light beam having a required numerical aperture NA with respect to the observation position of the sample. Therefore, in such a configuration, the observation conditions of the sample using the solid immersion lens, such as the numerical aperture and the amount of light, can be appropriately set according to the inner diameter and outer diameter of each ring shape, the number of protrusions, and the like. Various configurations may be used for the specific shape and arrangement of the protrusions.

  Further, the grooves 75a and 75b provided in the protrusions 74a and 74b can be used as the optical contact liquid discharge groove. That is, the grooves 75a and 75b are used for the evaporation of the above-mentioned optical contact liquid or the penetration of the solvent, and these can be performed faster. However, these grooves 75a and 75b may be omitted if unnecessary, for example, when an optical contact liquid is not used.

  13A is a bottom view and FIG. 13B is a cross-sectional view taken along arrows VIIII-VIIII showing the configuration of the sixth embodiment of the solid immersion lens according to the present invention. The configuration of the solid immersion lens 45 of the present embodiment is the same as that of the solid immersion lens 1A of the first embodiment, but the configuration of the plurality of protrusions provided on the bottom surface serving as the mounting surface for the sample is different. .

  In the solid immersion lens 45, the bottom surface 3 serving as a mounting surface for the sample has a plurality of protrusions. That is, in the configuration shown in FIG. 13, a plurality of projecting portions 76 projecting downward are provided at regular intervals on the circumference indicated by the dotted line. Further, these protrusions 76 are formed so that the installation pattern of the protrusions 76 and the resulting contact pattern with respect to the sample are axisymmetric with respect to the central axis Ax.

Specifically, as shown in FIG. 13A, the protrusion 76 on the bottom surface 3 is fixed so that its center is located on the circumference of the radius r ₁ with the sphere center O as the center. They are arranged at an angular interval θ. In the configuration example shown in FIG. 13A, the angular interval θ is 45 degrees, four protrusions centered at the point where the circumference of the radius r ₁ intersects each of the x-axis and the y-axis, and the radius r Two protrusions centered on the point where the circumference of _{1 and} the straight line forming 45 degrees intersect with the x axis, and the point where the circumference of the radius r _{1 and} the line forming −45 degrees intersect with the x axis A total of eight protrusions 76 are provided by the two protrusions. Each of these protrusions 76, is formed in a circular shape having a radius r _2. The radii r ₁ and r ₂ are set so that, for example, light beams having a numerical aperture NA of 1.2 to 1.4 can pass. The radii r ₁ and r ₂ may be set in accordance with a light flux having an NA value different from the numerical aperture NA.

  In such a configuration, among the eight projecting portions 76, on the circumference centered on the ball center O, a pair of axial symmetry is formed from the two projecting portions located on the opposite side across the central axis Ax. Thus, a set of four axisymmetric protrusions constitutes an installation pattern of the protrusions 76 that are axially symmetric with respect to the central axis Ax as a whole.

  The effect of the solid immersion lens 45 according to the present embodiment will be described.

  The solid immersion lens 45 has a plurality of protrusions 76, and contacts the sample at these protrusions 76. For this reason, it is possible to obtain a light flux passing through a desired optical path. In addition, by bringing the solid immersion lens 45 into contact with the sample via the plurality of protrusions 76, the solid immersion lens 45 can be stably placed on the sample without tilting, and position control becomes easy. In addition, the possibility of sticking being prevented by dust is lower than that of a plano-convex lens. In addition, since the force required to separate the solid immersion lens 45 and the sample is extremely weak, there is no possibility of damaging the solid immersion lens 45 and the like, and the solid immersion lens 45 can be used repeatedly.

  Further, the solid immersion lens 45 can be used in the same semiconductor inspection apparatus as described in the first embodiment, and the inspection can be performed by the same method. The solid immersion lens 45 comes into contact with the semiconductor device at the protrusion 76. Further, the gap between the adjacent protrusions is an outlet for discharging the optical contact liquid used when the solid immersion lens 45 and the sample are brought into close contact with each other. Therefore, it is possible to evaporate the optical contact liquid or infiltrate the solvent faster than the plano-convex lens. For this reason, the solid immersion lens 45 can be optically adhered to the semiconductor device in a short time or peeled from the semiconductor device. Such an effect can be similarly obtained for samples other than semiconductor devices.

In the above-described embodiment, the projecting portion 76 that is axially symmetric with respect to the central axis Ax is configured such that the circular projecting portion 76 is disposed on the circumference around the spherical center O. Therefore, the sample is observed by setting the radius r ₁ of the circle forming the circumference on which the protrusions are installed and the radius r ₂ of the circles forming the protrusions according to the light flux of the numerical aperture NA desired to pass. Only a light beam having a necessary numerical aperture can be selectively passed with respect to the position. Therefore, in such a configuration, the observation conditions of the sample using the solid immersion lens, such as the numerical aperture and the amount of light, can be appropriately set according to the radius of the circle in which the protrusion is arranged, the shape of the protrusion, and the like. In addition, about the specific shape and arrangement | sequence structure of a protrusion part, you may use various structures.

  FIG. 14A is a bottom view and FIG. 14B is a cross-sectional view along arrow X-X showing the configuration of the seventh embodiment of the solid immersion lens according to the present invention. The configuration of the solid immersion lens 46A of the present embodiment is the same as that of the solid immersion lens 1A of the first embodiment, but the configuration of the plurality of protrusions provided on the bottom surface serving as the mounting surface for the sample is different. .

  In the solid immersion lens 46A, the bottom surface 3 serving as a mounting surface for the sample has a protruding portion. That is, in the structure shown in FIG. 14, the protrusion part 78 which protrudes below is provided in the ring shape. The projecting portion 78 is formed so that the installation pattern of the projecting portion 78 and the resulting contact pattern with the sample are axisymmetric with respect to the central axis Ax.

  Specifically, the projecting portion 78 on the bottom surface 3 has a ring shape having an inner diameter r and an outer diameter R with the ball center O as the center, as shown in FIG. The ring-shaped outer diameter R constituting the protruding portion 78 coincides with the radius R of the circle constituting the bottom surface 3.

  As for the cross-sectional shape of the protruding portion 78, a portion corresponding to the protruding portion 78 on the bottom surface 3 that is separated from the central axis Ax by a distance r or more gradually protrudes downward in accordance with the distance from the central axis Ax. Is getting higher. In the cross-sectional shape represented by the XX arrow cross-sectional view of FIG. 14B, a smooth curve is drawn in which the protruding height is highest at the outer edge portion of the bottom surface 3. Further, the protrusion height at the bottom surface 3 is uniform on the circumference equidistant from the central axis Ax.

  In such a configuration, the protrusion 78 has the same protrusion height at a position equidistant from the central axis Ax, and the installation pattern of the protrusion 78 that is axially symmetric with respect to the central axis Ax as a whole is configured. .

  Further, a groove as described above with reference to FIG. 12 that functions as an optical contact liquid discharge groove may be provided in the protruding portion 78. In FIG. 14A, the protrusion 78 is provided with a groove 79 on both the + y side and the −y side so as to cross the protrusion 78 along the y-axis. For this reason, even if the groove 79 is provided, the contact pattern of the bottom surface 3 with respect to the sample by the protrusion 78 is axisymmetric with respect to the center axis Ax of the lens. However, this groove 79 may not be provided if it is not necessary.

  The effect of the solid immersion lens 46A according to the present embodiment will be described.

  The solid immersion lens 46 </ b> A has a protrusion 78, and contacts the sample at the protrusion 78. For this reason, it is possible to obtain a light flux passing through a desired optical path. Further, by bringing the solid immersion lens 46A into contact with the sample via the ring-shaped protruding portion 78, the solid immersion lens 46A can be stably placed on the sample without tilting, and position control becomes easy. Furthermore, the possibility that the sticking is prevented by dust is lower than that of the plano-convex lens. Further, since the force required to separate the solid immersion lens 46A and the sample is weaker than that of the plano-convex lens, the solid immersion lens 46A or the like is not damaged, and the solid immersion lens 46A can be used repeatedly. .

  Further, the solid immersion lens 46A can be used in the same semiconductor inspection apparatus as described in the first embodiment, and the inspection can be performed by the same method. The solid immersion lens 46 </ b> A contacts the semiconductor device at the protrusion 78. Further, a groove 79 can be provided. For this reason, the optical contact liquid can be evaporated or the solvent can be permeated faster than the plano-convex lens, and the solid immersion lens 46A can be optically attached to the semiconductor device or peeled off from the semiconductor device in a short time. Such an effect can be similarly obtained for samples other than semiconductor devices.

  In the above embodiment, the inner side of the ring shape of the projecting portion 78, that is, the inside of a circle having a radius r centered on the ball center O does not have a projecting structure. For this reason, the sample and the solid immersion lens 46A do not come into contact with each other in the central portion, and the central light beam is not used for observing the sample. Therefore, the same effect as when the central shielding stop is used can be obtained. For example, when this solid immersion lens 46A is applied to the backside observation of a semiconductor device, it is possible to eliminate the contrast of the metal wiring on the backside of the semiconductor substrate and selectively take out and observe only the three-dimensional shape of the substrate. In such a configuration, the observation conditions of the sample using the solid immersion lens such as the numerical aperture NA and the amount of light can be appropriately set according to the inner diameter and outer diameter of the ring shape.

  Various configurations may be used for the specific shape and arrangement of the protrusions on the bottom surface 3. For example, in FIG. 14, the protruding portion 78 has a shape in which the protruding height downward from the bottom surface 3 gradually increases, but the inner portion thereof can be planar. Alternatively, the inner portion of the protrusion 78 may have a curved surface shape that is continuous with the protrusion 78. In such a configuration, the entire bottom surface 3 becomes a protruding portion whose protruding height downwards as viewed from the spherical center O gradually increases. Further, a step may be provided between the projecting portion 78 and the inner portion thereof, and the inner portion of the projecting portion 78 may be formed in a concave shape.

  15A is a bottom view, FIG. 15B is a cross-sectional view along arrow XI-XI, and FIG. 15C is a cross-sectional view along arrow XII-XII. In the solid immersion lens 46B, a protrusion 80 is provided at a portion of the bottom surface 3 serving as a mounting surface with respect to the sample at a distance of L or more from the y axis in each of the + x direction and the −x direction. Specifically, on the bottom surface 3, protrusions 80 are formed at portions satisfying x ≦ −L and x ≧ L, respectively. Thus, the protrusion does not need to have a ring shape. Even in such a configuration, the contact pattern of the bottom surface 3 with respect to the sample by the protrusion 80 is axisymmetric with respect to the central axis Ax. In addition, about the cross-sectional shape of a protrusion part, it is the same as that of FIG.

  FIG. 16 is a (a) bottom view and (b) XIII-XIII arrow sectional view showing the configuration of the eighth embodiment of the solid immersion lens according to the present invention. The configuration of the solid immersion lens 47 of the present embodiment is the same as that of the solid immersion lens 1A of the first embodiment, but the configuration of the plurality of protrusions provided on the bottom surface serving as the mounting surface for the sample is different. .

  In the solid immersion lens 47, the bottom surface 3 serving as a mounting surface for the sample has a protruding portion. That is, in the configuration shown in FIG. 16, the projecting portions 81 projecting downward are provided so as to be two-dimensionally arranged over the entire bottom surface 3. In addition, the installation pattern of the protrusions 81 and the contact pattern with respect to the sample thereby are formed so as to be symmetric with respect to the central axis Ax. Further, in this configuration, portions of the bottom surface 3 excluding the protruding portion 81 are recessed portions 82 and 83. In the recesses 82 and 83, similarly to the protrusion 81, the installation pattern of the recesses 82 and 83 and the contact pattern with respect to the sample are axially symmetric with respect to the central axis Ax.

  Specifically, as shown in FIG. 16A, the recesses 82 on the bottom surface 3 are arranged in the x-axis direction and the y-axis direction, and the arrangement intervals dx are constant in the x-axis direction and the y-axis direction, respectively. , Dy are arranged in a two-dimensional matrix. In the configuration example shown in FIG. 16A, there are 7 columns in the y-axis direction, 4 in the first column from the negative side of the y-axis, 6 in the second column, 8 in the third column, and the center column. A total of 44 recesses 82 are provided, with 8 in the 4th row, 8 in the 5th row, 6 in the 6th row and 4 in the 7th row. Each of these recesses 82 is formed in a circular shape with a radius r. In addition, a groove-like recess 83 is formed between the recesses 82 adjacent to each other in the x-axis direction and the y-axis direction.

  In such a configuration, among the 44 concave portions 82, two concave portions located on the opposite side across the central axis Ax constitute an axially symmetric set, and 22 axially symmetric concave pairs. Thus, an installation pattern of the projecting portions 81 that is axisymmetric with respect to the central axis Ax as a whole is configured for both the projecting portions and the recessed portions.

  The effect of the solid immersion lens 47 according to the present embodiment will be described.

  The solid immersion lens 47 has a protruding portion 81 provided with a recess 82, and contacts the sample at the protruding portion 81. For this reason, it is possible to obtain a light flux passing through a desired optical path. Further, by bringing the solid immersion lens 47 into contact with the sample via the protruding portion 81 provided over the entire bottom surface 3, the solid immersion lens 47 can be stably placed on the sample without tilting, and position control is facilitated. In addition, since the concave portion 82 is provided over the entire surface, the possibility that the fixing is prevented by dust is lower than that of the plano-convex lens. Further, since the force required to separate the solid immersion lens 47 and the sample is less than that of the plano-convex lens, the solid immersion lens 47 or the like is not damaged, and the solid immersion lens 47 can be used repeatedly. .

  Further, the solid immersion lens 47 can be used in the same semiconductor inspection apparatus as described in the first embodiment, and the inspection can be performed by the same method. The solid immersion lens 47 is in contact with the semiconductor device at the protrusion 81, and the protrusion 81 is provided with recesses 82 over the entire surface in a two-dimensional matrix. For this reason, the optical contact liquid can be evaporated or the solvent can be permeated faster than the plano-convex lens, and the solid immersion lens 47 can be optically attached to the semiconductor device or peeled off from the semiconductor device in a short time. Moreover, the groove-shaped recessed part 83 which connects the recessed part 82 functions as an optical contact | adherence liquid discharge groove. Such an effect can be similarly obtained for samples other than semiconductor devices.

  Moreover, in the said embodiment, since the solid immersion lens 47 can be manufactured by forming the recessed part 82 in the protrusion part 81 which is a plane in the bottom face 3, manufacture becomes easy. Moreover, since the protrusion is provided uniformly over the entire surface, excellent operability can be obtained. Further, in such a configuration, the observation conditions of the sample using the solid immersion lens such as the numerical aperture NA and the light amount can be appropriately set depending on the number and shape of the concave portions. In addition, about the specific shape and arrangement | sequence structure of the part which a protrusion part and a protrusion part appear, you may use various structures.

  INDUSTRIAL APPLICABILITY The present invention can be used as a solid immersion lens that can transmit a light beam with a desired numerical aperture and can be easily controlled in position when optically coupled to a sample to be observed.

It is (a) bottom view and (b) side view of the solid immersion lens which concerns on 1st Embodiment. It is a figure which shows the specific protrusion structure of a protrusion part. It is the (a) bottom view and (b) sectional view of the solid immersion lens which is a modification of the solid immersion lens which concerns on 1st Embodiment. It is a bottom view of the solid immersion lens which is a modification of the solid immersion lens which concerns on 1st Embodiment. It is the (a) bottom view and (b) sectional view of the solid immersion lens which is a modification of the solid immersion lens which concerns on 1st Embodiment. It is the (a) bottom view and (b) sectional view of the solid immersion lens which is a modification of the solid immersion lens which concerns on 1st Embodiment. It is a block block diagram of the semiconductor inspection apparatus which has the solid immersion lens which concerns on this embodiment. It is (a) bottom view and (b) sectional drawing of the solid immersion lens which concerns on 2nd Embodiment. It is (a) bottom view and (b) sectional drawing of the solid immersion lens which concerns on 3rd Embodiment. It is the (a) bottom view and (b) sectional view of the solid immersion lens concerning a 4th embodiment. It is a figure which shows a mode that a solvent is sent with a wind to the solid immersion lens which concerns on 4th Embodiment. It is the (a) bottom view and (b) sectional view of the solid immersion lens concerning a 5th embodiment. It is (a) bottom view and (b) sectional drawing of the solid immersion lens which concerns on 6th Embodiment. It is (a) bottom view and (b) sectional view of a solid immersion lens concerning a 7th embodiment. It is the (a) bottom view of the solid immersion lens which is a modification of the solid immersion lens which concerns on 7th Embodiment, (b) sectional drawing, (c) sectional drawing. It is (a) bottom view of the solid immersion lens which concerns on 8th Embodiment, (b) sectional drawing. It is a graph which shows the relationship between the curvature radius of the bottom face of a solid immersion lens, and the pressure required when making an observation target object contact | adhere.

Explanation of symbols

1A to 1E, 41, 42 to 45, 46A, 46B, 47 ... solid immersion lens, 2 ... top surface of solid immersion lens, 3 ... bottom surface of solid immersion lens, 4a to 4c, 5a to 5f, 7a, 7b, 8a to 8c, 71, 72, 73, 74a, 74b, 76, 78, 80, 81 ... projecting portion, 6 ... sample, 6a ... upper surface of sample, 6b ... lower surface of sample, 13 ... image acquisition unit, 14 ... optical system, DESCRIPTION OF SYMBOLS 15 ... Stage, 16 ... Inspection | inspection part, 18 ... Stage, 20 ... Objective lens, 30 ... Solid immersion lens drive part, 51 ... Observation control part, 52 ... Stage control part, 53 ... Solid immersion lens control part, 61 ... Image analysis , 62 ... indicating part, 75a, 75b, 79, 83 ... groove, 82 ... concave part, 90 ... solvent, O ... ball center, Ax ... central axis of solid immersion lens, A ... observation part, B ... control part, D ... analysis part, F ... pressure, l ₁ -l ₄ ... light, P ... observation position, S ... semiconductor device Vice

Claims (10)

A solid immersion lens attached to a sample to be observed and used for observing the sample,
A first surface having a spherical shape with a predetermined radius;
A mounting surface for the sample, and a second surface having a plurality of protrusions,
Said second surface, each of the plurality of protrusions are provided at a position away from the central axis, the contact pattern for the sample by the plurality of protrusions, it becomes axisymmetric with respect to the central axis The solid immersion lens is formed so that the central portion of the second surface does not contact the sample .   The second surface includes, as the plurality of protrusions, at least two protrusions formed at positions sandwiching the central axis so that the contact pattern with respect to the sample is axially symmetric with respect to the central axis. The solid immersion lens according to claim 1, wherein the solid immersion lens is provided.   3. The solid immersion lens according to claim 2, wherein the second surface has a plurality of sets of protrusions provided so as to sandwich the central axis with the two protrusions serving as a set of protrusions. 4. .   The solid immersion lens according to claim 2, wherein the two protrusions are each formed in a circular shape, an elliptical shape, a rectangular shape, or a polygonal shape.   In the second surface, the plurality of projecting portions have two axes orthogonal to the central axis as the x axis and the y axis, the x axis direction and the y axis direction as the arrangement directions, and the x axis direction and the y axis direction. 2. The solid immersion lens according to claim 1, wherein each of the solid immersion lenses is arranged in a two-dimensional matrix at a constant arrangement interval.   The plurality of protrusions on the second surface are each formed in a fan shape having a predetermined opening angle radially extending from the central axis, and are provided at regular angular intervals. The solid immersion lens described.   In the second surface, the plurality of projecting portions are each formed in a ring shape and are concentrically arranged, and are provided with grooves that allow communication between the inside and the outside. The solid immersion lens according to claim 1.   2. The solid immersion lens according to claim 1, wherein in the second surface, the plurality of protrusions are arranged at a constant angular interval on a circumference centered on the central axis.   In the second surface, the plurality of protrusions are ring-shaped with the central axis as a center, and the outer diameter of the plurality of protrusions coincides with the radius of a circle constituting the second surface, The solid immersion lens according to claim 1, wherein a groove is provided to communicate with the outside.   In the second surface, the plurality of projecting portions are separated by at least L in the + x direction and the −x direction from the y axis, where x ≦ −L, with the two axes orthogonal to the central axis as the x axis and the y axis. The solid immersion lens according to claim 1, wherein the solid immersion lens is formed in a portion satisfying x ≧ L.

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