JP4800749B2 - Infrared microscope with calibration function and infrared microscope calibration method - Google Patents

Description

  The present invention relates to an infrared microscope having a calibration function that uses infrared light transmitted through a semiconductor substrate such as silicon as illumination light, and a calibration method for the infrared microscope.

  Conventionally, as an infrared microscope, one that positions a semiconductor chip as disclosed in Patent Document 1 is known. FIG. 13 shows a schematic configuration of such an infrared microscope. An infrared light source 103 as a transmission illumination light source is disposed below a sample stage 102 on which a semiconductor chip 101 is mounted as a sample, and above the sample stage 102. An infrared microscope unit 105 having a CCD camera 104 is arranged, and infrared light transmitted through the semiconductor chip 101 from the infrared light source 103 is picked up by the CCD camera 104 via the infrared microscope unit 105, and is displayed on the monitor 106 as image information. It is trying to display.

  In this case, the image of the semiconductor chip 101 displayed on the monitor 106 is displayed with, for example, a pattern portion that does not transmit infrared light of the semiconductor chip 101 as a shadow, and the positioning of the semiconductor chip is performed using this image information. Done.

  On the other hand, when the infrared light source 103 is used as an epi-illumination light source, the infrared light reflected by the pattern portion of the semiconductor chip 101 that does not transmit infrared light is imaged by the CCD camera 104, and this image information is used. ing.

  Further, in such an infrared microscope, for example, those disclosed in Patent Document 2 and Patent Document 3 are also known as those used for positioning from the back surface of a semiconductor chip or for internal observation after chip bonding. Yes.

  By the way, what is disclosed in these Patent Documents 1 to 3 is an object to be observed having a silicon substrate such as the semiconductor chip 101. Therefore, when observing infrared light transmitted through the silicon substrate, an objective is used. When the numerical aperture NA of the lens is large and the thickness dimension of silicon is large, spherical aberration may occur.

For this reason, as disclosed in Patent Document 4, a lens that uses an objective lens designed to correct or adjust spherical aberration has been proposed.
JP-A-8-247744 JP-A-5-152401 JP 2000-276233 A JP 2005-049363 A

  However, an objective lens designed to be able to correct or adjust spherical aberration has a problem that it cannot exhibit sufficient lens performance when observed through silicon. In addition, such an infrared microscope needs to be periodically calibrated particularly when used for measurement applications in the industrial field. Also in this case, since the objective lens can correct or adjust the spherical aberration according to the sample such as silicon, it is not possible to obtain a good image necessary for calibration if the reference sample for calibration is observed without passing through the silicon. . For this reason, it is conceivable to form a pattern on a silicon substrate and use it as a calibration reference sample. In this case, however, it is necessary to manufacture a new calibration reference sample, and to ensure traceability. There is also the problem that it is difficult.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an infrared microscope having a calibration function and a calibration method for an infrared microscope that can realize highly reliable calibration.

According to the first aspect of the present invention, in the infrared microscope in which infrared light is used as illumination light and observed through the silicon member, the incident infrared light is emitted toward the calibration reference sample, the said infrared light reflected by the calibration reference sample is provided so as to enter an objective lens in which the infrared light is corrected aberration generated when it passes through the silicon member, before Symbol silicon member equivalent A light transmission member having various characteristics, a holding unit that is detachably attached to the objective lens, and holds the light transmission member on an optical path between the objective lens and the calibration reference sample, and the holding unit in transmitted through the light transmitting member held, and the control unit asking you to calibration information based on the observation image of the calibration reference samples taken by incident on the objective lens, and stores the calibration information And 憶 means is characterized by comprising a.

  A second aspect of the invention is characterized in that, in the first aspect of the invention, the objective lens is capable of adjusting a correction amount of aberration generated when the objective lens is transmitted through the silicon member.

  The invention according to claim 3 is the invention according to claim 1, wherein the light transmission member has an equivalent influence on a silicon chip having a thickness dimension assumed at the time of designing the objective lens or the aberration, It consists of an optical member whose thickness is adjusted according to the refractive index.

  A fourth aspect of the invention is characterized in that, in the third aspect of the invention, the silicon chip or the optical member is subjected to an antireflection treatment of the infrared light on at least one surface.

The invention according to claim 5 is the invention according to claim 1, wherein the silicon chip or the optical member is fixed to the holding means.

  According to a sixth aspect of the invention, in the first aspect of the invention, the light transmitting member is detachable from the holding means.

The invention according to claim 7 is the invention according to any one of claims 1 to 6 , wherein the infrared microscope is an infrared confocal microscope .

The invention according to claim 8 is a method for calibrating an infrared microscope in which infrared light is used as illumination light and observation is performed through a silicon member, and the incident infrared light is emitted toward a calibration reference sample. In addition, on the optical axis of the objective lens, which is provided so that the infrared light reflected by the reference sample for calibration is incident, and which corrects the aberration generated when the infrared light passes through the silicon member, A step of holding a light transmissive member having characteristics equivalent to the silicon member and placing the light transmissive member by a holding means detachably provided on the objective lens; and on a light path through the light transmissive member. Arranging the calibration reference sample; and calibrating the infrared microscope based on an observation image of the calibration reference sample obtained by passing through the light transmitting member and entering the objective lens. For information, it is characterized by comprising the step of storing calibration information.

The invention according to claim 9 is the invention according to claim 8, wherein the light transmitting member has an equivalent influence on a silicon chip having a thickness dimension assumed at the time of designing the objective lens or the aberration, It consists of an optical member whose thickness is adjusted according to the refractive index .
According to a tenth aspect of the present invention, in the ninth aspect of the invention, the silicon chip or the optical member is fixed to the holding means.
The invention according to claim 11 is the invention according to claim 8, wherein the light transmitting member is detachable from the holding means.

  ADVANTAGE OF THE INVENTION According to this invention, the infrared microscope which has the calibration function which enabled realization of reliable calibration, and the calibration method of an infrared microscope can be provided, without preparing the special reference sample for calibration.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 shows a schematic configuration of a reflection type infrared microscope to which the first embodiment of the present invention is applied. In FIG. 1, reference numeral 1 denotes an infrared microscope section, which has an objective lens 2. A sample table 3 is arranged corresponding to the tip of the objective lens 2. The sample stage 3 is for mounting a sample 4 (or a calibration reference sample 11) having a silicon substrate such as a semiconductor chip, and is movable in the vertical direction in the figure, that is, in the Z-axis direction.

  The infrared microscope unit 1 is provided with an infrared light source 5 as an epi-illumination light source and a CCD camera 6. The infrared light source 5 emits infrared light in a predetermined wavelength region, and this infrared light is condensed on the sample 4 (or the calibration reference sample 11) through the objective lens 2. The CCD camera 6 images the infrared light reflected from the sample 4 (or the calibration reference sample 11) via the objective lens 2 and the infrared microscope unit 1. A control unit 7 is connected to the CCD camera 6.

  The control unit 7 acquires two-dimensional information from the image captured by the CCD camera 6 and displays it on the monitor 71. Further, the control unit 7 compares the two-dimensional information acquired from the calibration reference sample 11 with a reference value (nominal value of the reference sample) prepared in advance using analysis software or the like, and calculates calibration information from these comparison results. Is stored in a storage means (not shown). This calibration information is then used when correcting the two-dimensional information acquired from the captured image of the sample 4.

  FIG. 2 is for further explaining the objective lens 2. In this case, the objective lens 2 can correct aberrations (especially spherical aberration) generated when passing through the silicon in the sample 4 and is designed in accordance with an infrared wavelength capable of transmitting silicon. Silicon thickness correction is performed so that the lens performance is most exhibited when passing through the silicon. At this time, the refractive index of silicon (Si) used for the design is about 3.5 when the wavelength of infrared light is 1300 nm. In addition, since the thickness of a silicon substrate used for a general semiconductor chip or the like is about 100 to 700 μm, a thickness of about 400 μm, for example, a central value in this range is set as a reference thickness for design. However, 100 μm or 700 μm may be used as a design reference thickness depending on the application. In addition, the objective lens 2 has a large NA, and the amount of spherical aberration increases due to the silicon thickness. For example, the objective lens 2 is designed for a lens that requires higher precision performance such as an infrared confocal microscope. The usable range may be limited to about ± 100 μm with respect to the thickness.

  Such an objective lens 2 is provided with a silicon holder 8 as a holding means at the tip. The silicon holder 8 includes a cylindrical main body 8a having a bottom 8b, and a through hole 8c is formed at the center of the bottom 8b. In such a silicon holder 8, the surface of the bottom 8 b is along a surface perpendicular to the optical axis a of the objective lens 2 in a state where the tip of the objective lens 2 is fitted in the hollow portion of the cylindrical main body 8 a. Further, the optical axis a of the objective lens 2 is disposed so as to pass through the through hole 8c.

  On the surface of the bottom 8b in the silicon holder 8, a silicon chip 9 having a characteristic equivalent to that of the silicon substrate of the sample 4 is placed as a light transmitting member. In this case, the surface of the bottom 8b on which the silicon chip 9 is placed is processed so that the silicon chip 9 is not distorted, and the silicon chip 9 is detachably mounted on the smoothed surface. . The silicon chip 9 is polished on both sides and diced with a thickness dimension assumed when the objective lens 2 is designed. Furthermore, as shown in FIG. 3, the silicon chip 9 is provided with an antireflection coating 9a on both sides as an antireflection treatment in accordance with the wavelength range of infrared light. This antireflection coat 9a may be only on one side. By doing so, loss of light quantity, interference, and the like due to reflection of infrared light on the front and back surfaces of the polished silicon chip 9 are prevented.

  Next, a specific method for fixing the silicon holder 8 to the tip of the objective lens 2 will be described.

  In FIG. 4, a large-diameter through-hole 8d communicating with the through-hole 8c is further formed in the bottom 8b of the cylindrical main body 8a of the silicon holder 8, and an abutting portion 8e is formed at the opening peripheral edge of the through-hole 8d. is doing. The abutting portion 8e is a member in which the tip end surface 2a of the objective lens 2 is brought into contact with the hollow portion of the cylindrical main body 8a and the tip end portion 2a of the objective lens 2 is in contact. The mounting positioning of the tool 8 is performed. In this case, the silicon chip 9 is placed on the step portion 8f formed between the through holes 8c and 8d.

  In this way, the objective lens 2 is inserted into the hollow portion of the silicon holder 8, and the tip end surface 2a is brought into contact with the abutting portion 8e formed on the bottom portion 8b of the cylindrical main body 8a, thereby holding the silicon. Since the tool 8 can be positioned, tilting when the silicon holder 8 is attached to the objective lens 2 can be prevented and fixed in a stable state.

  FIG. 5 shows another method of fixing the silicon holder 8 to the objective lens 2. In this case, the silicon holder 8 has a screw hole 8g formed on the side surface of the cylindrical body 8a. A fixing screw 10 is provided in the screw hole 8g. The fixing screw 10 has a screw main body 10a to be screwed into the screw hole 8g and a knob 10b provided at a base end portion of the screw main body 10a. The silicon holder 8 can be fixed to the objective lens 2 by adjusting the screwing amount to the screw body and pressing the side surface of the objective lens 2 with the tip of the screw body 10a.

  In this case, the screw body 10a may be formed of a relatively soft member such as a resin so as not to damage the side surface of the objective lens 2.

  In this way, the tip of the objective lens 2 is inserted into the hollow portion of the silicon holder 8, the knob 10b of the fixing screw 10 is turned, the screw body 10a is screwed into the screw hole 8g, and the objective is made at the tip of the screw body 10a. The silicon holder 8 can be fixed to the objective lens 2 by pressing the side surface of the lens 2. In this case, the silicon holder 8 can be easily removed from the objective lens 2 by turning the knob 10b in the opposite direction to loosen the screw body 10a.

  FIG. 6 shows a further different fixing method of the silicon holder 8 to the objective lens 2. In this case, the objective lens 2 has a screw portion 2b on the peripheral surface of the tip portion. Further, a screw portion 8h corresponding to the screw portion 2b on the objective lens 2 side is formed on the inner peripheral surface of the opening of the cylindrical main body 8a of the silicon holder 8, and this screw portion 8h is connected to the screw portion 2b on the objective lens 2 side. The silicon holder 8 can be fixed to the distal end portion of the objective lens 2 by screwing into the objective lens 2.

In this way, the screw portion 8 h on the inner peripheral surface of the opening of the cylindrical body 8 a of the silicon holder 8 is screwed into the screw portion 2 b on the peripheral surface of the tip portion of the objective lens 2, thereby holding the tip portion of the objective lens 2 in silicon. It can be fixed in a state of being inserted into the hollow portion of the tool 8. Also in this case, the silicon holder 8 can be easily detached from the objective lens 2 by loosening the screwing of the silicon holder 8.
Note that the silicon holder 8 can be fixed to the objective lens 2 by using a click, or by providing a slit in the holder and fixing it with a tightening toy structure, in addition to the fixing method described above.

  Next, an actual calibration procedure using the objective lens 2 configured as described above will be described with reference to a flowchart shown in FIG.

  First, in step 701, the silicon chip 9 is mounted on the bottom 8 b of the cylindrical body 8 a of the silicon holder 8, and the silicon holder 8 is fixed to the objective lens 2. In this case, there are various methods for fixing the silicon holder 8 as described above.

  Next, in step 702, the calibration reference sample 11 is placed on the sample stage 3. In this case, the calibration reference sample 11 is formed by forming a linear Cr pattern or the like on the surface of the calibration reference sample 11. The calibration reference sample 11 is not particularly prepared for an infrared microscope as long as it reflects infrared light, and a calibration reference sample such as a general microscope can also be used.

  In this case, there is no problem even if the order of step 701 and step 702 is reversed.

  Next, in step 703, the sample stage 3 is moved in the Z-axis direction to focus on the surface of the calibration reference sample 11. Then, the process proceeds to step 704 and is adjusted to the item to be calibrated. For example, when the magnification is calibrated, the two-dimensional information of the calibration reference sample 11 is acquired. In this case, infrared light from the infrared light source 5 passes through the objective lens 2 and the silicon chip 9 from the infrared microscope unit 1 and irradiates the reference sample 11 for calibration. Further, the infrared light reflected by the calibration reference sample 11 is imaged by the CCD camera 6 via the objective lens 2 and the infrared microscope unit 1.

  In this case, the infrared light transmitted through the objective lens 2 passes through the silicon chip 9 and is irradiated onto the calibration reference sample 11. In this state, the objective lens 2 has the smallest spherical aberration in terms of design. Therefore, a good image necessary for calibration without aberration can be acquired from the CCD camera 6.

  Next, in step 705, two-dimensional information such as the line width of the linear pattern on the calibration reference sample 11 is acquired from the image captured by the control unit 7 with the CCD camera 6. The control unit 7 compares the acquired two-dimensional information with a reference value (nominal value of the reference sample) prepared in advance using analysis software or the like, and obtains calibration information of the infrared microscope from these comparison results. The calibration information is stored in a storage means (not shown).

  Therefore, in this way, the silicon holder 8 holding the silicon chip 9 is attached to the objective lens 2 designed to correct the aberration (spherical aberration) generated when passing through the silicon. Since the calibration reference sample 11 is irradiated with infrared light through the silicon chip 9 from 2 and the reflected light is imaged by the CCD camera 6, a good image necessary for calibration without aberration from the CCD camera 6. And calibration information with high reliability can be obtained from the two-dimensional information based on this image. In this case, since the silicon holder 8 holding the silicon chip 9 can be attached to and detached from the objective lens 2 and can be easily attached and detached, the calibration work can be easily performed. Further, it is not necessary to prepare a special reference sample 11 for calibration used for calibration work, and a calibration reference sample such as a microscope can be generally used, which can be economically advantageous. Furthermore, since the silicon chip 9 is provided with an anti-reflection coating 9a on at least one surface, it is possible to reduce light amount loss and interference due to reflection on the surface of the silicon chip 9, and to realize more accurate calibration. It becomes.

(Modification 1)
In the above-described embodiment, the case where the magnification is calibrated has been described. In this case, an infrared confocal microscope is an object as an infrared microscope for calibration. Further, as the calibration reference sample, reference step samples 19 forming the uneven portion 19a on the surface as shown in FIG. 8 for acquiring three-dimensional information is used. As this reference step sample 19, for example, a block gauge step sample or the like is used. The reference step sample 19 is not particularly prepared for an infrared microscope as long as it reflects infrared light, and a standard reference sample for calibration such as a general microscope can be used.

(Modification 2)
In the embodiment described above, the silicon chip 9 is simply placed on the surface of the bottom 8b in the silicon holder 8. For example, as shown in FIG. 9, the surface of the bottom 8b in the silicon holder 8 is used. It is also possible to fix the silicon chip 9 with a silicon-based adhesive 20 that has a very small stress change during bonding. In this way, since the silicon chip 9 is stably held in the silicon holder 8, the silicon holder 8 can be handled more easily. This is particularly effective when the silicon chip 9 is extremely thin.

(Modification 3)
In the embodiment described above, the silicon holder 8 is attached to the tip of the objective lens 2. For example, as shown in FIG. 10, the silicon holder 21 on which the silicon chip 9 is placed is used as the reference sample 11 for calibration. It may be possible to fix to. In this case, the silicon holder 21 has a protruding wall 21c along the periphery of the silicon chip mounting surface 21b having the opening 21a. The calibration reference sample 11 is fixed in the protruding wall 21c, and the objective lens 2 is fixed. Infrared light to be irradiated is condensed on the calibration reference sample 11 through the silicon chip 9 and the opening 21a, and the reflected light is incident on the objective lens 2 through the opening 21a and the silicon chip 9. ing.

  Further, for example, as shown in FIG. 11, the silicon holder 22 on which the silicon chip 9 is placed may be arranged on the sample table 3 on which the calibration reference sample 11 is placed. In this case, the silicon holder 22 has a protruding wall 22c along the periphery of the silicon chip mounting surface 22b having the opening 22a, and the tip of the protruding wall 22c is mounted on the sample table 3, The calibration reference sample 11 is arranged in the projecting wall 22c, the infrared light irradiated from the objective lens 2 is condensed on the calibration reference sample 11 through the silicon chip 9 and the opening 22a, and the reflected light is opened. The light is incident on the objective lens 2 through the part 22a and the silicon chip 9.

  With these configurations, the calibration reference sample 11 can be mounted more easily, so that the work is facilitated particularly when calibration is performed on a plurality of objective lenses.

(Modification 4)
In the above-described embodiment, the silicon chip 9 is used, but an optical member such as glass may be used instead. At this time, the thickness of the glass can be simply set simply by the ratio of the refractive index, but is precisely designed by optical simulation or the like. When such an optical member such as glass is used, it is easy to process. Therefore, it is advantageous particularly when high-precision flatness is required, and it is excellent in availability.

  Note that such an optical member such as glass can also be subjected to an antireflection treatment of infrared light, similarly to the silicon chip 9, or can be bonded and fixed to a holder corresponding to the silicon holder 22.

(Modification 5)
In the above-described embodiment, the example in which the objective lens 2 whose spherical aberration is corrected in advance is used. However, for example, as shown in FIG. 12, the objective lens 23 whose spherical aberration correction amount can be adjusted may be used. Is possible. The objective lens 23 has a correction ring 24. By rotating the correction ring 24, the distance between lens groups (not shown) inside the objective lens 23 is adjusted, and the correction amount of spherical aberration can be adjusted. It is. At this time, the adjustable range is designed to cover at least a silicon substrate thickness of 100 to 700 μm, and the adjustment amount is operated according to a scale (not shown) attached to the objective lens 23 and the correction ring 24. Can be set to an appropriate position. In addition, the objective lens 23 has a particularly large NA, and the amount of spherical aberration increases due to the silicon thickness. For example, the objective lens 23 is required to have high-precision performance such as the infrared confocal microscope. The usable range may be limited to about ± 100 μm with respect to the design thickness.

(Modification 6)
In the embodiment described above, a reflection type using an infrared light source 5 for epi-illumination has been described as an infrared microscope, but a transmission type using an infrared light source for transmission illumination may be used. I do not care. In that case, since the path of infrared light transmitted through the silicon chip 9 from the infrared light source for transmitted illumination and incident on the objective lens 2 is one way, the design of the objective lens 2 and the thickness of the silicon chip 9 are determined. It is necessary to use one designed for transmission observation. Further, the calibration reference sample 11 is suitable for transmission observation.

  In addition, this invention is not limited to the said embodiment, In the implementation stage, it can change variously in the range which does not change the summary.

  Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and is described in the column of the effect of the invention. If the above effect is obtained, a configuration from which this configuration requirement is deleted can be extracted as an invention.

The figure which shows schematic structure of the infrared microscope to which the 1st Embodiment of this invention is applied. The figure which shows schematic structure of the objective lens used for 1st Embodiment. The figure which shows schematic structure of the silicon chip used for 1st Embodiment. The figure which shows schematic structure of the silicon | silicone holder used for 1st Embodiment. The figure which shows schematic structure of the different silicon | silicone holder used for 1st Embodiment. The figure which shows schematic structure of the further different silicon | silicone holder used for 1st Embodiment. The flowchart for demonstrating operation | movement of 1st Embodiment. The figure which shows schematic structure of the reference | standard level | step difference sample used for the modification 1 of 1st Embodiment. The figure which shows schematic structure of the modification 2 of 1st Embodiment. The figure which shows schematic structure of the modification 3 of 1st Embodiment. The figure which shows schematic structure of the modification 3 of 1st Embodiment. The figure which shows schematic structure of the modification 5 of 1st Embodiment. The figure which shows schematic structure of an example of the conventional infrared microscope.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Infrared microscope part, 2 ... Objective lens 2a ... End part end surface, 2b ... Screw part 3 ... Sample stand, 4 ... Sample, 5 ... Infrared light source 6 ... CCD camera, 7 ... Control part 71 ... Monitor, 8 ... Silicon holder 8a ... Cylindrical body, 8b ... Bottom part 8c, 8d ... Through hole, 8f ... Step part, 8g ... Screw hole 8h ... Screw part, 9 ... Silicon chip 9a ... Anti-reflection coating, 10 ... Fixing screw 10a ... Screw Main body, 10b ... Knob 11 ... Reference sample for calibration, 11a ... Glass substrate 19 ... Reference step sample, 19a ... Uneven portion 20 ... Silicone adhesive, 21 ... Silicon holder 21a ... Opening, 21b ... Silicon chip mounting surface 21c ... Projection wall, 22 ... Silicon holder 22a ... Opening, 22b ... Silicon chip mounting surface 22c ... Projection wall, 23 ... Objective lens, 24 ... Correction ring

Claims (11)

In an infrared microscope that uses infrared light as illumination light and transmits through a silicon member for observation,
When the incident infrared light is emitted toward the calibration reference sample and the infrared light reflected by the calibration reference sample is incident, and the infrared light passes through the silicon member An objective lens that corrects the aberration generated in the
A light transmitting member having a front Symbol silicon member equivalent characteristics,
A holding means that is detachably attached to the objective lens and holds the light transmitting member on an optical path between the objective lens and the calibration reference sample;
Said transmitted through the light transmitting member held by the holding means, the control unit asking you to calibration information based on the observation image of the calibration reference samples taken by entering the objective lens,
Storage means for storing the calibration information,
An infrared microscope having a calibration function.   2. The infrared microscope having a calibration function according to claim 1, wherein the objective lens is capable of adjusting a correction amount of an aberration generated when the objective lens is transmitted through the silicon member.   The light transmitting member is made of a silicon chip having a thickness dimension assumed at the time of designing the objective lens or an optical member having an equivalent influence on the aberration and having a thickness adjusted according to a refractive index. An infrared microscope having a calibration function according to claim 1.   The infrared microscope having a calibration function according to claim 3, wherein the silicon chip or the optical member is subjected to an antireflection treatment of the infrared light on at least one surface. The infrared microscope having a calibration function according to claim 3, wherein the silicon chip or the optical member is fixed to the holding unit.   2. The infrared microscope having a calibration function according to claim 1, wherein the light transmitting member is detachable from the holding means. The infrared microscope having a calibration function according to any one of claims 1 to 6, wherein the infrared microscope is an infrared confocal microscope. An infrared microscope calibration method that uses infrared light as illumination light and performs observation through a silicon member,
When the incident infrared light is emitted toward the calibration reference sample and the infrared light reflected by the calibration reference sample is incident, and the infrared light passes through the silicon member The light transmission member is held by a holding means that is detachably attached to the objective lens while holding a light transmission member having a characteristic equivalent to that of the silicon member on the optical axis of the objective lens in which the aberration generated in the lens is corrected. A step of arranging,
Placing the calibration reference sample on the optical path through the light transmitting member;
Obtaining calibration information of the infrared microscope based on an observation image of the calibration reference sample obtained by passing through the light transmitting member and entering the objective lens, and storing the calibration information;
A calibration method for an infrared microscope, comprising: The light transmitting member is made of a silicon chip having a thickness dimension assumed at the time of designing the objective lens or an optical member having an equivalent influence on the aberration and having a thickness adjusted according to a refractive index. The infrared microscope calibration method according to claim 8. The infrared microscope calibration method according to claim 9, wherein the silicon chip or the optical member is fixed to the holding unit. 9. The infrared microscope calibration method according to claim 8, wherein the light transmitting member is detachable from the holding means.

Images