Scanning probe microscope and position adjustment method of scanning probe microscope

Abstract

The present invention provides a scanning probe microscope and a method for adjusting the position of the scanning probe microscope. The cantilever has a probe at the front end. The irradiation unit irradiates the cantilever with laser light. The detection unit includes a light receiving surface for receiving the laser light reflected by the cantilever, and detects the laser light spot on the light receiving surface. The driving unit adjusts the position of the detection unit. The laser adjustment unit adjusts the laser light irradiated to the cantilever. If the cantilever is displaced when measuring the characteristics of a sample, the direction in which the laser light spot is displaced on the light receiving surface is set to a first direction, and the direction on the light receiving surface orthogonal to the first direction is set to a second direction, and the laser adjustment unit adjusts the laser light so that the length of the laser light spot in the second direction when adjusting the position of the detection unit is longer than the length of the laser light spot in the first direction when measuring the characteristics of the sample.

Description

Technical Field

[0001] The present invention relates to a scanning probe microscope and a position adjustment method of the scanning probe microscope. Background Art

[0002] In a scanning probe microscope, a cantilever beam formed with a probe, called a cantilever, is used. In a scanning probe microscope, changes in the warping or vibration of the cantilever are converted into changes in reflected light of a laser irradiated onto the back of the cantilever, and then detected by a photodetector. In the photodetector, changes in the position, intensity, phase, etc. of the reflected light are detected and converted into various physical information (for example, refer to Japanese Patent Publication No. 2000-346782). Summary of the invention

[0003] In a scanning probe microscope, before measuring a sample, the position of the photodetector needs to be adjusted so that the reflected light from the cantilever accurately enters the photodetector and the reflected light spot is located in the center of the photodetector. This photodetector position adjustment is a necessary operation when the cantilever is replaced, so it is expected to be performed in a short time.

[0004] A scanning probe microscope is generally constructed such that when at least a portion of the reflected light from the laser is incident on the photodetector during position adjustment of the photodetector, the direction of the photodetector relative to the reflected light can be inferred based on the incident position of the reflected light and the photodetector can be moved in that direction.

[0005] However, when the reflected light of the laser is incident on a part other than the photodetector, it is impossible to estimate the direction of the photodetector relative to the reflected light. In other words, it is impossible to determine in which direction the photodetector should be moved so that the reflected light of the laser can be incident on the photodetector. Therefore, the photodetector needs to be moved randomly until the reflected light of the laser is incident on the photodetector, which is the main reason why the position adjustment of the photodetector is time-consuming.

[0006] Therefore, an object of the present invention is to provide a scanning probe microscope and a method for adjusting the position of a scanning probe microscope that can shorten the time required for adjusting the position of a photodetector.

[0007] A scanning probe microscope according to one aspect of the present invention comprises a cantilever, an irradiation unit, a detection unit, a drive unit, a measurement unit, and a laser adjustment unit. The cantilever has a probe at the front end. The irradiation unit irradiates the cantilever with laser light. The detection unit includes a light receiving surface for receiving the laser light reflected by the cantilever, and detects the laser light spot on the light receiving surface. The drive unit adjusts the position of the detection unit. The measurement unit is configured to measure the characteristics of the sample based on the displacement of the cantilever calculated according to the displacement of the laser light spot on the light receiving surface. The laser adjustment unit adjusts the laser light irradiated to the cantilever. If the cantilever is displaced when measuring the characteristics of the sample, the direction in which the laser light spot is displaced on the light receiving surface is set to a first direction, and the direction on the light receiving surface orthogonal to the first direction is set to a second direction, and the laser adjustment unit adjusts the laser light so that the length of the laser light spot in the second direction when adjusting the position of the detection unit is longer than the length of the laser light spot in the first direction when measuring the characteristics of the sample.

[0008] The above objects, features, aspects and advantages and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a schematic diagram showing the structure of the scanning probe microscope according to the first embodiment.

[0010] Figure 2 It is a diagram showing a probe, a cantilever, and a support.

[0011] Figure 3 It is a diagram for explaining the displacement of the laser spot in the photodetector during sample measurement.

[0012] Figure 4 It is a diagram for explaining an example of position adjustment of a photodetector according to a comparative example.

[0013] Figure 5 This is a diagram for explaining an example of position adjustment of the photodetector according to the first embodiment.

[0014] Figure 6 This is a schematic diagram showing the structure of a scanning probe microscope according to a modified example of the first embodiment.

[0015] Figure 7 This is a flowchart for explaining control of position adjustment of a photodetector according to a modification of the first embodiment.

[0016] Figure 8 This is a schematic diagram showing the structure of a scanning probe microscope according to the second embodiment.

[0017] Fig. 9This is a diagram for explaining an example of position adjustment of the photodetector according to the second embodiment.

[0018] Fig.10 This is a diagram showing the relationship between the spot diameter of a laser beam and the intensity of the laser beam.

[0019] Fig.11 This is a flowchart for explaining control of position adjustment of the photodetector according to the second embodiment.

[0020] Fig.12 This is a diagram for explaining an example of position adjustment of the photodetector according to the third embodiment.

[0021] Fig.13 This is a flowchart illustrating control of position adjustment of the photodetector according to the third embodiment.

[0022] Fig.14 This is a flowchart for explaining an example of control of adjustment of the size and shape of the laser spot according to the first to third embodiments. DETAILED DESCRIPTION

[0023] Hereinafter, the embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same reference numerals are attached to the same or corresponding parts in the drawings, and the description thereof will not be repeated in principle.

[0024] [Implementation Method 1]

[0025] Figure 1 This is a diagram showing the structure of a scanning probe microscope 100 according to the first embodiment.

[0026] Reference Figure 1 The scanning probe microscope 100 according to the first embodiment includes an optical system 80 , a cantilever 2 , a measuring unit 14 , driving units 11 and 44 , a scanner 43 , a laser adjustment unit 20 , and an operation unit 13 .

[0027] The cantilever 2 has a probe 7 at the free end or the tip of the surface. The sample 9 and the probe 7 are arranged on the scanner 43 so as to face each other. The cantilever 2 is displaced by the interatomic force (attractive force or repulsive force) between the probe 7 and the sample 9.

[0028] The optical system 80 irradiates the back side of the cantilever 2 with laser light and detects the laser light reflected on the back side of the cantilever 2. The optical system 80 can detect the displacement caused by the bending of the cantilever 2. The optical system 80 includes a laser light source 30, a beam splitter 3 as a first reflector, a reflector 4 as a second reflector, and a photodetector 5.

[0029] The laser light source 30 is composed of a laser oscillator that emits laser light, a collimating lens, a focusing lens, etc. The photodetector 5 is composed of a photodiode that detects the incident laser light, etc. The laser light emitted from the laser light source 30 is reflected by the beam splitter 3 and is incident on the cantilever 2. The laser light source 30 and the beam splitter 3 correspond to one embodiment of the “irradiation section”.

[0030] The laser light is reflected by the cantilever 2, and then reflected by the reflector 4 to be incident on the light receiving surface 50 of the photodetector 5. When the cantilever 2 is displaced, the position of the laser light incident on the light receiving surface 50 of the photodetector 5 is also displaced. That is, in the scanning probe microscope 100, the displacement of the cantilever 2 can be measured based on the displacement of the laser light spot on the light receiving surface 50 of the photodetector 5. The photodetector 5 corresponds to an embodiment of the "detection unit". Hereinafter, the laser light spot is also referred to as "spot" or "laser light spot".

[0031] The laser adjustment unit 20 adjusts the size, shape, intensity, etc. of the spot of the laser beam of the laser light source 30 by adjusting the collimator lens and the focusing lens of the laser light source 30 .

[0032] The measuring unit 14 calculates the position of the laser beam incident on the photodetector 5 based on the detection signal of the laser beam detected by the optical system 80. The measuring unit 14 measures the characteristics of the sample 9 based on the displacement of the cantilever 2 obtained according to the change in the calculated laser beam position. For example, the measuring unit 14 creates a force curve representing the time change of the applied force based on the time change of the displacement of the cantilever 2. The measuring unit 14 sends a control signal for driving the scanner 43 to the driving unit 44.

[0033] The display unit 16 displays the calculation results and measurement results of the measurement unit 14. The display unit 16 displays, for example, the position of the laser spot in the photodetector 5. The display unit 16 is, for example, a liquid crystal display.

[0034] The driving portion 11 is a mechanism for adjusting the position of the photodetector 5. The driving portion 11 is, for example, a screw.

[0035] The operating part 13 is used by the analyst to drive the driving part 11. The operating part 13 is, for example, an adjustment screw.

[0036] The display unit 16, the drive unit 11, and the operation unit 13 are used to adjust the laser beam before starting to measure the sample so that it is appropriately incident on the photodetector 5. Specifically, the analyst operates the operation unit 13 while confirming the position of the laser spot displayed on the display unit 16 on the photodetector 5, thereby moving the drive unit 11 to adjust the position of the photodetector 5.

[0037] The driving unit 44 drives the scanner 43 to change the relative positional relationship between the sample 9 placed on the scanner 43 and the probe 7 .

[0038] Figure 2 is a diagram showing the probe 7, the cantilever 2 and the support 15. Figure 2 As shown, the probe 7 is mounted on the front end of the cantilever 2. The holder 15 is a member that supports the cantilever 2. The laser light from the beam splitter 3 is incident on, for example, a region on the back side of the probe 7 in the cantilever 2, and the incident laser light is reflected by the cantilever 2. The reflected light is reflected by the reflective mirror 4 and is incident on the photodetector 5.

[0039] Figure 3 2 is a diagram for explaining the displacement of the laser spot in the photodetector 5 during the sample measurement. The light receiving surface 50 is a surface in the photodetector 5 for detecting the laser spot reflected by the cantilever 2. Figure 2 The laser reflected by the cantilever 2 shown forms a substantially circular laser spot s0 on the light receiving surface 50. The light receiving surface 50 has a square shape with a length of one side d2. The light receiving surface 50 is divided into four parts. The photodetector 5 is configured to detect the position of the laser spot s0 by comparing the ratios at which the laser spot s0 is detected on each of the divided light receiving surfaces.

[0040] In more detail, when the cantilever 2 is not displaced before the sample measurement, the position of the photodetector 5 is adjusted so that the laser spot s0 is located at the center of the light receiving surface 50. If the cantilever 2 is displaced during the sample measurement, the position of the laser spot s0 is displaced in the direction (direction of arrow a1) corresponding to the displacement direction (i.e., the bending direction) of the cantilever. The direction of arrow a1 corresponds to the "first direction". The diameter d1 of the laser spot s0 is adjusted to a diameter suitable for measuring the sample by the laser adjustment unit 20.

[0041] Hereinafter, the position adjustment of the photodetector 5 will be described. First, the position adjustment of the photodetector 5 according to the comparative example will be described.

[0042] Figure 4 1 is a diagram for explaining an example of position adjustment of the photodetector 5 involved in the comparative example. Before measuring the sample, the position of the photodetector 5 is adjusted so that Figure 4 As shown in (3), the laser spot s1 is located at the center of the light receiving surface 50. Figure 4 (1) Figure 4 (2) is a diagram showing the process of adjustment to the appropriate position.

[0043] Figure 4(1) indicates a state in which the irradiation range of the laser is outside the light receiving surface 50 and the light spot s1 is not in the light receiving surface 50. In this state, the photodetector 5 cannot detect the laser, and therefore cannot determine in which direction of the light receiving surface 50 the laser spot s1 is located. Therefore, the analyst moves the photodetector 5 in the direction indicated by the arrow a2 (hereinafter also referred to as direction a2) and the direction indicated by the arrow a3 (hereinafter also referred to as direction a3) until at least a portion of the laser spot s1 is included in the light receiving surface 50. In addition, the direction a2 is the same as the direction a3. Figure 3 Therefore, the direction a3 corresponds to the "second direction" orthogonal to the direction a1. The center c1 of the light spot s1 and the distance d3 between the light spot s1 and the light receiving surface 50 will be described later.

[0044] Figure 4 (2) indicates a state in which at least a portion of the laser spot s1 is included in the light receiving surface 50. In this state, the analyst can infer the direction of the laser spot s1 relative to the light receiving surface 50. Therefore, the analyst operates the operation unit 13 to drive the photodetector 5 in the direction of the inferred laser spot s1, and the analyst makes adjustments so that the laser spot s1 is located at the center of the light receiving surface 50.

[0045] Figure 4 (3) shows that as a result of moving the photodetector 5 in the direction of the estimated laser spot s1 , the laser spot s1 is adjusted to be located at the center of the light receiving surface 50 .

[0046] Thus, in the comparative example, the position of the photodetector 5 is adjusted so that the laser spot s1 is located at the center of the light receiving surface 50. However, in the comparative example, when the laser is located outside the light receiving surface 50 at the beginning of adjusting the position of the photodetector 5, it may take time until at least a part of the laser spot s1 is included in the light receiving surface 50. In other words, it may take time until the laser spot s1 is located outside the light receiving surface 50. Figure 4 (1) to Figure 4 The time until (2) becomes longer.

[0047] Therefore, in the scanning probe microscope 100 involved in this embodiment, the shape and / or size of the laser spot is adjusted to make the laser spot easy to enter the light receiving surface. Thus, the time until at least a part of the laser spot is included in the light receiving surface 50 is shortened. In Embodiment 1, an example is described in which the length of the laser spot in the a2 direction is unchanged and the length in the a3 direction is enlarged.

[0048] Figure 5 This is a diagram for explaining an example of position adjustment of the photodetector according to the first embodiment. Figure 5 is with Figure 4 For comparison, the Figure 5 In the figure, the laser spot s2 and Figure 4 The laser spot s1 is different.

[0049] exist Figure 5 In the figure, the length d1 of the laser spot s2 in the direction a2 (i.e., the direction in which the spot s2 is displaced due to the displacement (bending) of the cantilever) is Figure 4 The length d1 of the laser spot s1 in the a2 direction of (1) is the same. The length d2 of the laser spot s2 in the a3 direction is adjusted to be greater than d1 and the same as the length d2 of the light receiving surface 50 in the a3 direction. That is, the laser spot s2 has an ellipse with a major diameter of d2 and a minor diameter of d1.

[0050] Figure 5 The position of the center c2 of the light spot s2 in (1) relative to the light receiving surface 50 is Figure 4 The position of the center c1 of the light spot s1 in (1) relative to the light receiving surface 50 is the same. However, Figure 5 The distance d4 between the light spot s2 and the light receiving surface 50 in (1) is Figure 4 The distance d3 between the light spot s1 and the light receiving surface 50 in (1) is small.

[0051] exist Figure 5 In the state (1), the laser spot s2 is located outside the light receiving surface 50, so it is impossible to determine in which direction the laser spot s2 is located relative to the light receiving surface 50. Therefore, the analyst moves the photodetector 5 along the directions a2 and a3 until the light receiving surface 50 includes at least a portion of the laser spot s2, that is, until the light receiving surface 50 becomes Figure 5 Here, as mentioned above, Figure 5 The distance d4 between the light spot s2 and the light receiving surface 50 in (1) is Figure 4 The distance d3 between the spot s1 and the light receiving surface 50 in (1) is small. Therefore, it is considered that there is a high possibility that the time taken until at least a part of the laser spot is included in the light receiving surface 50 can be shortened.

[0052] When becoming Figure 5 When the state (2) is reached, the analyst can estimate the direction of the laser spot s2 relative to the light receiving surface 50. Therefore, the analyst operates the operation unit 13 to move the photodetector 5 in the estimated direction of the laser spot s2 so that the laser spot s2 is located at the center of the light receiving surface 50. As a result, the laser spot s2 is as shown in FIG. Figure 5 As in (3), it is adjusted to be located at the center of the light receiving surface 50.

[0053] exist Figure 5 In (3), the length d1 in the direction a1 corresponding to the displacement direction of the cantilever is the same as that in the comparative example. Figure 5 The measurement of the sample under the condition of (3) can also be achieved with Figure 4 The same measurement accuracy is achieved when measuring the sample in (3). Therefore, it is not necessary to adjust the laser spot after adjusting the position of the photodetector 5 and before measuring the sample, so no extra time is required.

[0054] And, in the above Figure 4 and Figure 5 In the description of FIG. 5 , the state where the laser spots s1 and s2 are located outside the light receiving surface 50 when the position adjustment of the photodetector 5 is started is considered (ie, Figure 4 (1) Figure 5 (1)), but in fact, there is also a state in which at least a part of the laser spots s1 and s2 is included in the light receiving surface 50 when the position adjustment of the photodetector 5 is started (that is, Figure 4 (2) Figure 5 Here, when the position adjustment is started, even if the positional relationship between the photodetector 5 and the centers c1 and c2 of the laser spots s1 and s2 is the same, since the width of the spot s2 in the direction a3 is wide, the possibility that at least a portion of the spot s2 is included in the light receiving surface 50 is higher than that of the spot s1. That is, when the laser spot s2 involved in Embodiment 1 is used, it is more likely that a portion of the laser spot is included in the light receiving surface 50 when the position adjustment of the photodetector 5 is started, compared with the laser spot s1 involved in the comparative example. Therefore, in Embodiment 1, the possibility that there is no need to search for the laser spot outside the light receiving surface 50 is also increased, and it is expected that the time for position adjustment of the photodetector 5 can be shortened.

[0055] In addition, Figure 5 , the light receiving surface 50 is shown as a square, but the shape of the light receiving surface 50 is not limited thereto, and may be, for example, a rectangle or a circle. In addition, the length of the laser spot s2 in the a3 direction is set to be the same as one side of the light receiving surface 50, which is d2, but the length of the laser spot s2 in the a3 direction is not limited thereto, as long as it is longer than the length of the laser spot s1 in the a3 direction of the comparative example within a range that can ensure sufficient intensity detected in the light receiving surface 50.

[0056] As described above, the scanning probe microscope 100 according to the first embodiment does not change the length of the spot s2 in the direction a2 but increases the length in the direction a3, compared to the conventional scanning probe microscope according to the comparative example. Thus, when the laser spot is located outside the light receiving surface 50 during the position adjustment of the photodetector 5, the time until at least a portion of the laser spot is included in the light receiving surface 50 of the photodetector 5 can be shortened. Furthermore, when the position adjustment of the photodetector 5 is started, the probability that at least a portion of the laser spot is included in the light receiving surface 50 of the photodetector 5 can be increased. Therefore, the time taken for the position adjustment of the photodetector 5 can be shortened. In addition, the size of the spot corresponding to the displacement direction of the cantilever of the scanning probe microscope 100 according to the first embodiment is equivalent to the size of the spot corresponding to the displacement direction of the cantilever of the conventional scanning probe microscope. Therefore, even if the laser spot is not adjusted after the position adjustment, the sample can be measured with the same accuracy as the conventional scanning probe microscope. Therefore, there is an advantage that no extra time is spent before the analysis of the sample.

[0057] [Variation of Embodiment 1]

[0058] Figure 6 This is a schematic diagram showing the structure of a scanning probe microscope 100B according to a modification of the first embodiment. Figure 6 is with Figure 1 The comparison chart is Figure 1 The difference is that in Figure 6 A drive unit 11B, a drive control unit 12, and an operation unit 13B are added. The scanning probe microscope 100B controls the drive unit 11B by the drive control unit 12 according to the instruction of the operation unit 13B, thereby automatically adjusting the position of the photodetector 5.

[0059] The driving unit 11B is a mechanism for moving the position of the photodetector 5. The driving unit 11B is obtained by adding a mechanism for moving the driving unit 11 such as a motor to the driving unit 11.

[0060] The operation unit 13B is used by the analyst to instruct the drive control unit 12 to start the position adjustment of the photodetector 5. The operation unit 13B is, for example, a touch panel, a button, or the like.

[0061] The drive control unit 12 is configured to automatically perform the position control of the photodetector 5 that is controlled by the analyst in Embodiment 1. The drive control unit 12 receives an instruction to start position adjustment of the photodetector 5 from the operation unit 13B. The drive control unit 12 receives a detection signal of the photodetector 5 from the measurement unit 14, and controls the drive unit 11B based on the signal, thereby adjusting the position of the photodetector 5. Specifically, the drive control unit 12 determines the moving direction and moving distance of the photodetector 5 based on the detection signal of the photodetector 5, and controls the drive unit 11B to move the photodetector 5.

[0062] Figure 7 1 is a flowchart for explaining the control of the position adjustment of the photodetector 5 according to the modification of the first embodiment. When the drive control unit 12 receives an instruction to start the position adjustment of the photodetector 5 from the operation unit 13B, the drive control unit 12 executes Figure 7 Flowchart of the process.

[0063] In step S01, the drive control section 12 determines whether an instruction to start position adjustment of the photodetector 5 is received from the operation section 13B. In the case where an instruction to start position adjustment of the photodetector 5 is not received from the operation section 13B ("No" in step S01), the drive control section 12 repeats step S01. In the case where an instruction to start position adjustment of the photodetector 5 is received from the operation section 13B ("Yes" in step S01), in step S02, the drive control section 12 performs a search for the laser spot s2 in the photodetector 5. The operation for searching the laser spot s2 in the photodetector 5 is, for example, to move the photodetector 5 along the Figure 5 The movement is such that the directions a2 and a3 of (1) move in sequence.

[0064] In step S03, the drive control unit 12 determines whether a spot detection signal indicating that at least a part of the laser spot s2 is detected on the light receiving surface 50 is received from the measuring unit 14. When a spot detection signal indicating that the laser spot s2 is detected on the light receiving surface 50 is not received from the measuring unit 14 ("No" in step S03), the drive control unit 12 returns the process to step S02 to continue searching for the laser spot s2 in the photodetector 5.

[0065] On the other hand, when receiving a spot detection signal indicating that the laser spot s2 is detected on the light receiving surface 50 from the measuring unit 14 (YES in step S03 ), in step S04 , the drive control unit 12 stops searching the photodetector 5 for the laser spot s2 .

[0066] In step S05, the drive control unit 12 calculates the direction of the laser spot s2 relative to the light receiving surface according to the position of the laser spot s2 on the light receiving surface 50. In step S06, the drive control unit 12 moves the photodetector 5 in the direction of the laser spot s2, thereby adjusting the position of the laser spot s2 to the center of the light receiving surface 50.

[0067] As described above, the scanning probe microscope 100B according to the modification of the first embodiment can obtain the same operational effects as those of the first embodiment and can also automatically adjust the position of the photodetector 5 , thereby reducing the burden on the analyst.

[0068] [Implementation Method 2]

[0069] In order to shorten the time required to adjust the position of the photodetector 5 compared to the scanning probe microscope according to the comparative example, the scanning probe microscope 100C according to the second embodiment makes the spot diameter during the position adjustment of the photodetector 5 larger than the spot diameter during the sample measurement. Figure 8 This is a schematic diagram showing the structure of a scanning probe microscope according to the second embodiment. Figure 8 is with Figure 6 The comparison chart is Figure 6 The difference is that the device control unit 17 and the operation unit 13C are added. Regarding the scanning probe microscope 100C, the device control unit 17 controls the laser adjustment unit 20 and the drive control unit 12 according to the command of the operation unit 13C, thereby enabling the position adjustment of the photodetector 5 and the laser adjustment accompanying the position adjustment.

[0070] The operation unit 13C is used by the analyst to instruct the device control unit 17 to start adjusting the position of the photodetector 5. The operation unit 13C is, for example, a touch panel, a button, or the like.

[0071] The device control section 17 appropriately controls the laser adjustment section 20 and the drive control section 12 in adjusting the position of the photodetector 5. Therefore, the device control section 17 transmits and receives signals to and from the laser adjustment section 20 and the drive control section 12 by wire or wirelessly.

[0072] Fig. 9 This is a diagram for explaining an example of position adjustment of the photodetector according to the second embodiment. Fig. 9 is with Figure 4 The comparison chart is Figure 4 The difference lies in the laser spot. Fig. 9 In the figures (1) to (3), the laser spot s3 is a circle having a diameter d2 equal to one side of the light receiving surface 50. The laser spot s3 being a circle means that the state of the laser spot s3 also includes a substantially circular state.

[0073] Fig.10 is a graph showing the relationship between the spot diameter of a laser beam and the intensity of the laser. Fig.10 As shown in FIG. 1 , the larger the spot diameter of the light beam is, the lower the intensity of the laser light is. The laser spot s3 is a laser spot that satisfies the condition that the range having an intensity exceeding the sensitivity limit is the diameter d2.

[0074] exist Fig. 9 In the state (1), the laser spot s3 is located outside the light receiving surface 50, so it is impossible to determine in which direction the laser spot s3 is located on the light receiving surface 50. Therefore, the drive control unit 12 moves the photodetector 5 in the directions a2 and a3 to a state in which at least a part of the laser spot s3 is included in the light receiving surface 50, that is, Fig. 9 Here, Fig. 9 The diameter ratio of the spot s3 in (1) is Figure 4 The diameter of the spot s1 in (1) is large. Figure 4 Compared with the comparative example, the time taken until the light spot enters the light receiving surface can be shortened. In addition, the probability that a part of the laser light spot is already included in the light receiving surface 50 when the position adjustment of the photodetector 5 is started can be increased.

[0075] When becoming Fig. 9 When the state (2) is reached, the drive control unit 12 can estimate the direction of the laser spot s3 relative to the light receiving surface 50. Therefore, the drive control unit 12 controls the drive unit 11B to move the photodetector 5 in the estimated direction of the laser spot s3 so that the laser spot s3 is located at the center of the light receiving surface 50. As a result, Fig. 9 As in (3), the laser spot s3 is adjusted to be located at the center of the light receiving surface 50.

[0076] When becoming Fig. 9 In the state (3), the laser adjustment unit 20 adjusts the size of the laser so that the diameter of the laser spot s3 becomes the diameter d1 ( Fig. 9 (4)).

[0077] Fig.11 1 is a flowchart for explaining the control of the position adjustment of the photodetector according to Embodiment 2. When the device control unit 17 receives an instruction to start the position adjustment of the photodetector 5, the device control unit 17 and the drive control unit 12 execute Fig.11 Flowchart of the process.

[0078] In step S21, the device control unit 17 determines whether an instruction to start adjusting the position of the photodetector 5 is received from the operation unit 13C. In the case where an instruction to start adjusting the position of the photodetector 5 is not received from the operation unit 13C ("No" in step S21), the device control unit 17 repeats step S21. In the case where an instruction to start adjusting the position of the photodetector 5 is received from the operation unit 13C ("Yes" in step S21), in step S22, the device control unit 17 controls the laser adjustment unit 20 to adjust the focusing lens and / or the collimating lens of the laser light source 30 so that the diameter of the laser spot s3 becomes d2. In step S23, the device control unit 17 causes the laser light source 30 to irradiate the laser.

[0079] In step S24, the device control unit 17 controls the drive control unit 12 to perform a search for the laser spot s3 in the photodetector 5. Specifically, the device control unit 17 controls the photodetector 5 to move along the Fig. 9 The directions a2 and a3 of (1) move in sequence.

[0080] In step S25, the device control unit 17 determines whether a spot detection signal indicating that at least a part of the laser spot s3 is detected on the light receiving surface 50 is received from the drive control unit 12. When no spot detection signal indicating that the laser spot s3 is detected on the light receiving surface 50 is received from the drive control unit 12 ("No" in step S25), the device control unit 17 returns the process to step S24 and continues to search for the laser spot s3 in the photodetector 5.

[0081] On the other hand, when receiving a spot detection signal indicating that the laser spot s3 is detected on the light receiving surface 50 from the drive control unit 12 (YES in step S25 ), in step S26 , the device control unit 17 stops searching the photodetector 5 for the laser spot s3 .

[0082] In step S27, the drive control unit 12 calculates the direction of the laser spot relative to the light receiving surface based on the position of the laser spot detected on the light receiving surface 50. In step S28, the drive control unit 12 moves the photodetector 5 in the direction of the laser spot based on the calculation result, thereby adjusting the position of the laser spot to the center of the light receiving surface 50. Then, a signal indicating the completion of the adjustment is sent to the device control unit 17.

[0083] In step S29 , the device control unit 17 controls the laser adjustment unit 20 to adjust the focusing lens of the laser light source 30 so that the diameter of the laser spot s3 becomes d1 .

[0084] As described above, the scanning probe microscope 100C according to the second embodiment can obtain the same effects as those of the first embodiment by making the diameter of the laser spot when adjusting the position of the photodetector 5 larger than the diameter of the laser spot when measuring the sample.

[0085] [Implementation method 3]

[0086] Fig.12 This is a diagram for explaining an example of position adjustment of the photodetector according to the third embodiment. Fig.12 is with Figure 4 For comparison, the Fig.12 In the figure, the size of the laser spot s4 is Figure 4 The size of the laser spot s3 is different.

[0087] exist Fig.12 In the figures (1) to (3), the laser spot s4 is a circle having a diameter d5 longer than one side of the light receiving surface 50. The fact that the laser spot s4 is a circle means that the state of the laser spot s4 also includes a substantially circular state. For example, d5 is the largest diameter of the region that can ensure an intensity above the sensitivity limit (see Fig.10 ).

[0088] exist Fig.12 In the state (1), since the laser spot s4 is located outside the light receiving surface 50, it is impossible to determine in which direction the laser spot s4 is located on the light receiving surface 50. Therefore, the drive control unit 12 moves the photodetector 5 along the direction a2 and the direction a3 until at least a part of the laser spot s4 is included in the light receiving surface 50, that is, Fig.12 Here, Fig.12 The diameter ratio of the spot s4 in (2) is Figure 4 The diameter of the spot s1 in (1) is large. Therefore, the time required until at least a portion of the spot s1 is included in the light receiving surface 50 can be shortened. In addition, there is a high probability that a portion of the laser spot s4 is already included in the light receiving surface 50 when the position adjustment of the photodetector 5 is started.

[0089] When becoming Fig.12 When the state (2) is reached, the drive control unit 12 can estimate the direction of the laser spot s4 relative to the light receiving surface 50. Therefore, the drive control unit 12 moves the photodetector 5 in the estimated direction of the laser spot s4 so that the laser spot s4 is located at the center of the light receiving surface 50. Since the laser spot s4 is larger than the light receiving surface 50, Fig.12 As in (3), at the stage where the entire light receiving surface 50 is included in the laser spot s4, the drive control unit 12 cannot recognize the direction of the laser spot s4.

[0090] When becoming Fig.12 In the state (3), the laser adjustment unit 20 adjusts the focusing lens of the laser light source 30 so that the diameter of the laser spot s4 is as small as possible within a range where at least a part of the laser spot s4 is included in the light receiving surface 50 and is larger than the diameter d1 of the laser spot s4 during the sample measurement. As a result, the laser spot s4 becomes Fig.12 The state of (4).

[0091] When the laser spot s4 becomes Fig.12 When the state (4) is reached, the drive control unit 12 can again estimate the direction of the laser spot s4 relative to the light receiving surface 50. Therefore, the drive control unit 12 moves the photodetector 5 in the estimated direction of the laser spot s4, and operates the operation unit 13C with the goal of locating the laser spot s4 at the center of the light receiving surface 50. Fig.12 When the entire light receiving surface 50 is within the range of the laser spot s4 as in (3), repeat Fig.12 (4)~ Fig.12 The action of (5).

[0092] When the laser spot s4 is located at the center of the light receiving surface 50, the laser adjustment unit 20 adjusts the laser so that the diameter of the laser spot s4 becomes a diameter d1 ( Fig.12 (6)).

[0093] Fig.13 This is a flowchart for explaining the position adjustment control of the photodetector 5 according to Embodiment 3. When the device control unit 17 receives an instruction to start the position adjustment of the photodetector 5, the device control unit 17 and the drive control unit 12 execute Fig.13 Flowchart of the process.

[0094] Steps S41 to S47 are equivalent to Fig.11 Steps S21 to S27 are described below, so their description is omitted.

[0095] In step S48 , the drive control unit 12 moves the photodetector 5 in the direction of the laser spot s4 , and adjusts the position of the laser spot to the center of the light receiving surface 50 .

[0096] In step S49, the drive control unit 12 determines whether the laser spot s4 is detected in the entire light receiving surface 50, and sends the determination result to the device control unit 17. When the laser spot s4 is detected in the entire light receiving surface 50 ("Yes" in step S49), in step S50, the device control unit 17 reduces the laser spot s4 within the range in which at least a part of the laser spot s4 is included in the light receiving surface 50, and returns the processing to step S48.

[0097] When the laser spot s4 is detected on a part of the light receiving surface 50 (No in step S49 ), in step S51 , the device control unit 17 instructs the laser adjustment unit 20 to adjust the laser light so that the diameter of the laser spot s4 becomes d1 .

[0098] As described above, the scanning probe microscope 100C according to the third embodiment can obtain the same effects as those of the first embodiment by making the diameter of the laser spot when adjusting the position of the photodetector 5 larger than the diameter of the laser spot when measuring the sample.

[0099] In the scanning probe microscope 100 and 100B according to the first embodiment and its variant, the configuration in which the laser spot s2 has an elliptical shape when the position of the photodetector 5 is adjusted and when the sample is measured is described. Here, the laser spot s2 may be configured to always have an elliptical shape. In addition, the laser spot s2 may be configured to be adjusted to an elliptical shape before the position adjustment of the photodetector 5 is started. In this case, Fig.14 As shown, the shape of the laser spot s2 may be adjusted in response to an instruction received from an analyst.

[0100] In the scanning probe microscope 100C according to the second and third embodiments, the configuration is described in which the laser spots s3 and s4 are adjusted to be substantially circular with a spot diameter larger than the spot diameter during sample measurement when the position of the photodetector 5 is adjusted. Fig.14 As shown, it is possible to adopt a configuration in which the shapes of the laser spots s3 and s4 are adjusted in accordance with an instruction received from an analyst.

[0101] Fig.14 This is a flowchart for explaining an example of control of adjustment of the size and shape of the laser spot according to the first to third embodiments.

[0102] In step S61, the scanning probe microscope 100, 100B, 100C determines whether a signal to start adjusting the size and shape of the laser spot is received from the analyst. This determination is achieved, for example, by the analyst pressing an operation button provided on the scanning probe microscope 100, 100B, 100C. In particular, in the scanning probe microscopes 100B and 100C according to the modification of Embodiment 1, Embodiment 2, and Embodiment 3, the operation button can be provided in the operation unit 13B and 13C.

[0103] When no signal for starting adjustment of the size and shape of the laser spot is received from the analyst (No in step S61 ), the scanning probe microscope 100 , 100B, or 100C repeats step S61 .

[0104] When the scanning probe microscope 100 , 100B, 100C receives a signal from the analyst to start adjusting the size and shape of the laser spot (YES in step S61 ), in step S62 , a signal instructing the laser adjuster 20 to start adjusting the size and shape of the laser spot is sent.

[0105] In step S63, when the laser adjustment unit 20 receives a signal indicating the start of adjusting the size and shape of the laser spot, it operates the collimating lens and / or focusing lens of the laser light source 30 to adjust the laser spot s2 to an elliptical shape, or adjusts the laser spots s3 and s4 to a roughly circular shape having a spot diameter larger than the spot diameter during sample measurement.

[0106] When measuring a sample using a scanning probe microscope, the laser spot can be measured in the direction corresponding to the bending direction of the cantilever 2, that is, the a2 direction (see Figure 5 ) to observe the shape of the sample. On the other hand, it is possible to observe the shape of the sample based on the displacement of the laser spot in the a3 direction (refer to Figure 5 ) to observe the friction force of the sample.

[0107] Therefore, the scanning probe microscope 100 according to the first embodiment is configured such that after adjusting the position of the photodetector 5 according to the elliptical laser spot s2, the length of the laser spot s2 in the a3 direction can be adjusted to be shorter, and the sample can be measured after the sample becomes a substantially perfect circle. Thus, in the scanning probe microscope 100, in addition to being able to observe the shape of the sample with high precision, the friction force of the sample can also be observed with high precision.

[0108] The laser spot can be adjusted in the a3 direction (refer to Figure 5 ) in the direction a3. Thus, the laser spot s2 of the first embodiment can be formed into an ellipse. In addition, even after the laser spot s2 is formed, the length of the laser spot s2 in the direction a3 can be adjusted.

[0109] In the first to third embodiments, circular (including substantially circular) and elliptical shapes are shown as examples of the shape of the laser spot. However, the shape of the laser spot is not limited thereto, and may be rectangular, for example.

[0110] In addition, in Embodiments 2 and 3, the laser spots s3 and s4 at the start of the position adjustment of the photodetector 5 are set to circles with diameters d2 and d5, respectively, but the present invention is not limited thereto, and any circle may be used as long as the spot diameter is larger than the spot diameter when the characteristics of the sample are measured. In addition, the laser spots s3 and s4 involved in Embodiments 2 and 3 may also be spots that satisfy the conditions that the length in the a2 direction is greater than d1 and the length in the a3 direction is greater than d1. Among them, as in Embodiment 2, there is an advantage that when the spot is incident on the light receiving surface 50, if it is known that the spot is adjusted to the radius of the center of the light receiving surface 50 even if the size adjustment is not performed, the size adjustment of the spot can be performed once. On the other hand, as in Embodiment 3, there is an advantage that if the spot diameter is set to the largest diameter of the area that can ensure the intensity above the sensitivity limit, the time until at least a part of the laser spot is included in the light receiving surface 50 can be further shortened.

[0111] As described above, in the embodiments of the present specification, it is possible to provide a scanning probe microscope and a method for adjusting the position of a scanning probe microscope that can shorten the time required for adjusting the position of a photodetector by adjusting a laser spot.

[0112] [Way]

[0113] It will be understood by those skilled in the art that the above-mentioned multiple exemplary embodiments are specific examples of the following aspects.

[0114] (Item 1) A scanning probe microscope according to one embodiment may include:

[0115] a cantilever having a probe at a front end;

[0116] an irradiation unit configured to irradiate laser light toward the cantilever;

[0117] a detection unit, comprising a light receiving surface for receiving the laser reflected by the cantilever, and detecting a light spot of the laser on the light receiving surface;

[0118] A driving unit, used for adjusting the position of the detection unit;

[0119] a measuring unit configured to measure a characteristic of a sample based on a displacement of the cantilever calculated from a displacement of a laser spot on the light receiving surface; and

[0120] a laser adjustment unit for adjusting the laser irradiated to the cantilever,

[0121] Among them, if the cantilever is displaced when measuring the characteristics of the sample, the direction in which the laser spot is displaced on the light receiving surface is set to a first direction, and the direction orthogonal to the first direction on the light receiving surface is set to a second direction, then the laser adjustment unit adjusts the laser so that the length of the laser spot in the second direction when adjusting the position of the detection unit is longer than the length of the laser spot in the first direction when measuring the characteristics of the sample.

[0122] According to the scanning probe microscope described in the first item, the time required for position adjustment of the detection section can be shortened.

[0123] (Item 2) In the scanning probe microscope described in the first item, the laser adjustment unit may adjust the laser so that the length of the laser spot in the first direction when adjusting the position of the detection unit is the same as the length of the laser spot in the first direction when measuring the characteristics of the sample.

[0124] According to the scanning probe microscope described in the second item, the time spent on adjusting the position of the detection unit can be shortened. In addition, even if the laser spot is not adjusted after the position of the detection unit is adjusted, the sample can be analyzed without reducing the accuracy. Therefore, no extra time will be spent before analyzing the sample.

[0125] (Item 3) In the scanning probe microscope described in Item 1, the laser adjustment unit may adjust the laser so that the length of the laser spot in the first direction when adjusting the position of the detection unit is longer than the length of the laser spot in the first direction when measuring the characteristics of the sample.

[0126] According to the scanning probe microscope described in the third aspect, the time required for position adjustment of the detection section can be shortened.

[0127] (Item 4) In the scanning probe microscope described in any one of Items 1 to 3, it may be further provided with a drive control unit for controlling the drive unit.

[0128] The drive control unit is configured to move the detection unit so that the laser beam is incident on the center of the light receiving surface when at least a part of the laser beam is incident on the light receiving surface when adjusting the position of the detection unit.

[0129] According to the scanning probe microscope described in the fourth aspect, in addition to being able to shorten the time required for position adjustment of the detection section, the position adjustment of the detection section can be performed automatically, thereby reducing the burden on the analyst.

[0130] (Item 5) A scanning probe microscope according to one embodiment may include:

[0131] a cantilever having a probe at a front end;

[0132] an irradiation unit configured to irradiate laser light toward the cantilever;

[0133] a detection unit, comprising a light receiving surface for receiving the laser reflected by the cantilever, and detecting a light spot of the laser on the light receiving surface;

[0134] A driving unit, used for adjusting the position of the detection unit;

[0135] a measuring unit configured to measure a characteristic of a sample based on a displacement of the cantilever calculated from a displacement of a laser spot on the light receiving surface; and

[0136] a laser adjustment unit for adjusting the laser irradiated to the cantilever,

[0137] Among them, if the cantilever is displaced when measuring the characteristics of the sample, the direction in which the laser spot is displaced on the light receiving surface is set to a first direction, and the direction orthogonal to the first direction on the light receiving surface is set to a second direction, then the laser adjustment unit adjusts the laser so that the length of the laser spot in the second direction is longer than the length of the laser spot in the first direction.

[0138] According to the scanning probe microscope described in the fifth item, the time spent on adjusting the position of the detection unit can be shortened. In addition, even if the laser spot is not adjusted after the position of the detection unit is adjusted, the sample can be analyzed without reducing the accuracy. Therefore, no extra time is spent before analyzing the sample.

[0139] (Item 6) A scanning probe microscope according to one embodiment may include:

[0140] a cantilever having a probe at a front end;

[0141] an irradiation unit configured to irradiate laser light toward the cantilever;

[0142] a detection unit, comprising a light receiving surface for receiving the laser reflected by the cantilever, and detecting a light spot of the laser on the light receiving surface;

[0143] A driving unit, used for adjusting the position of the detection unit;

[0144] a measuring unit configured to measure a characteristic of a sample based on a displacement of the cantilever calculated from a displacement of a laser spot on the light receiving surface; and

[0145] a laser adjustment unit for adjusting the laser irradiated to the cantilever,

[0146] The laser adjustment unit adjusts the laser so that a spot diameter of the laser when adjusting the position of the detection unit is larger than a spot diameter of the laser when measuring the characteristics of the sample.

[0147] According to the scanning probe microscope described in Item 6, the time required for position adjustment of the detection section can be shortened.

[0148] (Item 7) In a method for adjusting the position of a scanning probe microscope according to one embodiment, the scanning probe microscope may include a cantilever, an irradiation unit, and a detection unit.

[0149] The irradiation unit irradiates the cantilever with laser light.

[0150] The detection unit has a light receiving surface for detecting a light spot of the laser beam reflected by the cantilever.

[0151] The position adjustment method of the scanning probe microscope comprises the following steps:

[0152] If, when measuring the characteristics of the sample, the direction in which the laser spot is displaced on the light receiving surface is set as a first direction, and the direction on the light receiving surface orthogonal to the first direction is set as a second direction, the laser is adjusted so that the length of the laser spot in the second direction when adjusting the position of the detection unit is longer than the length of the laser spot in the first direction when measuring the characteristics of the sample;

[0153] moving the detection unit so that at least a portion of the adjusted laser spot is included in the light receiving surface; and

[0154] The detection unit is moved so that the spot of the laser beam is located at the center of the light receiving surface.

[0155] According to the position adjustment method of the scanning probe microscope described in the seventh item, the time taken for position adjustment of the detection unit can be shortened.

[0156] (Item 8) In a method for adjusting the position of a scanning probe microscope according to one embodiment, the scanning probe microscope may include a cantilever, an irradiation unit, and a detection unit.

[0157] The irradiation unit irradiates the cantilever with laser light.

[0158] The detection unit has a light receiving surface for detecting a light spot of the laser beam reflected by the cantilever.

[0159] The position adjustment method of the scanning probe microscope comprises the following steps:

[0160] If, when measuring the characteristics of the sample, the direction in which the laser spot is displaced on the light-receiving surface is set as a first direction, and the direction orthogonal to the first direction on the light-receiving surface is set as a second direction, the laser is adjusted so that the length of the laser spot in the second direction is longer than the length of the laser spot in the first direction;

[0161] moving the detection unit so that at least a portion of the adjusted laser spot is included in the light receiving surface; and

[0162] The detection unit is moved so that the spot of the laser beam is located at the center of the light receiving surface.

[0163] According to the position adjustment method of the scanning probe microscope described in the eighth item, the time spent on the position adjustment of the detection unit can be shortened. In addition, even if the laser spot is not adjusted after the position adjustment of the detection unit, the sample can be analyzed without reducing the accuracy. Therefore, no extra time will be spent before analyzing the sample.

[0164] (Item 9) In a method for adjusting the position of a scanning probe microscope according to one embodiment, the scanning probe microscope may include a cantilever, an irradiation unit, and a detection unit.

[0165] The irradiation unit irradiates the cantilever with laser light.

[0166] The detection unit has a light receiving surface for detecting a light spot of the laser beam reflected by the cantilever.

[0167] The position adjustment method of the scanning probe microscope comprises the following steps:

[0168] adjusting the laser so that the spot diameter of the laser is larger than the spot diameter of the laser when measuring the characteristics of the sample;

[0169] moving the detection unit so that at least a portion of the adjusted laser spot is included in the light receiving surface;

[0170] Based on at least a portion of the spot of the laser light included in the light receiving surface, the detection unit is moved in a direction of the spot of the laser light relative to the light receiving surface,

[0171] The detection unit is moved so that the spot of the laser beam is located at the center of the light receiving surface.

[0172] According to the method for adjusting the position of a scanning probe microscope described in Item 9, the time required for adjusting the position of the detection unit can be shortened.

[0173] Although the embodiments of the present invention have been described, the embodiments disclosed this time should be considered to be illustrative in all aspects and not restrictive. The scope of the present invention is indicated by the claims, and all modifications within the meaning and scope equivalent to the claims are included.

Claims

1. A scanning probe microscope comprising: a cantilever having a probe at a front end; an irradiation unit configured to irradiate laser light toward the cantilever; a detection unit, comprising a light receiving surface for receiving the laser reflected by the cantilever, and detecting a light spot of the laser on the light receiving surface; A driving unit, used for adjusting the position of the detection unit; a measuring unit configured to measure a characteristic of a sample based on a displacement of the cantilever calculated from a displacement of a laser spot on the light receiving surface; and a laser adjustment unit for adjusting the laser irradiated to the cantilever, in, If the cantilever is displaced in the direction toward which the sample and the probe are facing when measuring the characteristics of the sample, the direction in which the laser spot is displaced on the light receiving surface is set to a first direction, and the direction orthogonal to the first direction on the light receiving surface is set to a second direction, then the laser adjustment unit adjusts the laser so that the length of the laser spot in the second direction when adjusting the position of the detection unit is longer than the length of the laser spot in the first direction when measuring the characteristics of the sample.

2. The scanning probe microscope according to claim 1, wherein: The laser adjustment unit adjusts the laser so that the length of the laser spot in the first direction when adjusting the position of the detection unit is equal to the length of the laser spot in the first direction when measuring the characteristics of the sample.

3. The scanning probe microscope according to claim 1, wherein: The laser adjustment unit adjusts the laser light so that a length of a spot of the laser light in the first direction when adjusting the position of the detection unit is longer than a length of a spot of the laser light in the first direction when measuring a characteristic of the sample.

4. The scanning probe microscope according to any one of claims 1 to 3, wherein: further comprising a drive control unit for controlling the drive unit, The drive control unit is configured to move the detection unit so that the laser beam is incident on the center of the light receiving surface when at least a part of the laser beam is incident on the light receiving surface when adjusting the position of the detection unit.

5. A scanning probe microscope comprising: a cantilever having a probe at a front end; an irradiation unit configured to irradiate laser light toward the cantilever; a detection unit, comprising a light receiving surface for receiving the laser reflected by the cantilever, and detecting a light spot of the laser on the light receiving surface; A driving unit, used for adjusting the position of the detection unit; a measuring unit configured to measure a characteristic of a sample based on a displacement of the cantilever calculated from a displacement of a laser spot on the light receiving surface; and a laser adjustment unit for adjusting the laser irradiated to the cantilever, in, If the cantilever is displaced in the direction toward which the sample and the probe are facing when measuring the characteristics of the sample, the direction in which the laser spot is displaced on the light receiving surface is set as a first direction, and the direction orthogonal to the first direction on the light receiving surface is set as a second direction, then the laser adjustment unit makes the length of the laser spot in the second direction longer than the length of the laser spot in the first direction.

6. A scanning probe microscope comprising: a cantilever having a probe at a front end; an irradiation unit configured to irradiate laser light toward the cantilever; a detection unit, comprising a light receiving surface for receiving the laser reflected by the cantilever, and detecting a light spot of the laser on the light receiving surface; A driving unit, used for adjusting the position of the detection unit; a measuring unit configured to measure a characteristic of a sample based on a displacement of the cantilever calculated from a displacement of a laser spot on the light receiving surface; and a laser adjustment unit for adjusting the laser irradiated to the cantilever, in, The laser adjustment unit adjusts the laser light so that a spot diameter of the laser light when adjusting the position of the detection unit is larger than a spot diameter of the laser light when measuring the characteristics of the sample.

7. A method for adjusting the position of a scanning probe microscope, The scanning probe microscope includes a cantilever having a probe at the front end, an irradiation unit, and a detection unit. The irradiation unit irradiates the cantilever with laser light, The detection unit has a light receiving surface for detecting a light spot of the laser beam reflected by the cantilever. The position adjustment method of the scanning probe microscope comprises the following steps: If the cantilever is displaced in the direction in which the sample and the probe are facing each other when measuring the characteristics of the sample, the direction in which the laser spot is displaced on the light receiving surface is set as a first direction, and the direction on the light receiving surface that is orthogonal to the first direction is set as a second direction, then the laser is adjusted so that the length of the laser spot in the second direction when the position of the detection unit is adjusted is longer than the length of the laser spot in the first direction when the characteristics of the sample are measured; moving the detection unit so that at least a portion of the adjusted laser spot is included in the light receiving surface; and The detection unit is moved so that the spot of the laser beam is located at the center of the light receiving surface.

8. A method for adjusting the position of a scanning probe microscope, The scanning probe microscope includes a cantilever having a probe at the front end, an irradiation unit, and a detection unit. The irradiation unit irradiates the cantilever with laser light, The detection unit has a light receiving surface for detecting a light spot of the laser beam reflected by the cantilever. The position adjustment method of the scanning probe microscope comprises the following steps: If the cantilever is displaced in the direction in which the sample and the probe are facing each other when measuring the characteristics of the sample, the direction in which the laser spot is displaced on the light receiving surface is set as a first direction, and the direction on the light receiving surface that is orthogonal to the first direction is set as a second direction, and the laser is adjusted so that the length of the laser spot in the second direction is longer than the length of the laser spot in the first direction; moving the detection unit so that at least a portion of the adjusted laser spot is included in the light receiving surface; and The detection unit is moved so that the spot of the laser beam is located at the center of the light receiving surface.

9. A method for adjusting the position of a scanning probe microscope, The scanning probe microscope includes a cantilever, an irradiation unit and a detection unit. The irradiation unit irradiates the cantilever with laser light, The detection unit has a light receiving surface for detecting a light spot of the laser beam reflected by the cantilever. The position adjustment method of the scanning probe microscope comprises the following steps: Adjusting the laser so that the spot diameter of the laser is larger than the spot diameter of the laser when measuring the characteristics of the sample; moving the detection unit so that at least a portion of the adjusted laser spot is included in the light receiving surface; The detection unit is moved so that the spot of the laser beam is located at the center of the light receiving surface.

Images