JP4569123B2 - Microscope observation device - Google Patents

Description

  The present invention relates to a microscope observation apparatus used for observation of a semiconductor wafer, a liquid crystal substrate, and the like.

In a manufacturing process of a semiconductor circuit element or a liquid crystal display element, a circuit pattern formed on a semiconductor wafer or a liquid crystal substrate (generally referred to as “substrate”) is observed for defects, foreign matters, and the like using a microscope observation apparatus. The microscope observation apparatus is a combination of a mechanism for automatically transporting a substrate and an optical microscope system. The objective lens of the optical microscope system is a dry system, and the gap between the objective lens and the substrate to be observed is filled with a gas such as air (see, for example, Patent Document 1). In order to realize observation with higher resolution, it has been proposed to set the observation wavelength to the ultraviolet region.
JP 2001-118896 A

  By the way, in an apparatus using a dry objective lens, the numerical aperture of the objective lens cannot be made larger than “1”, so that there is a limit to improvement in resolution. Therefore, it is conceivable to use a known immersion method and use an immersion-type objective lens in place of the dry-type objective lens. In this case, the space between the tip of the immersion objective lens and the substrate to be observed is filled with a liquid such as water, and the numerical aperture of the objective lens is set to “1” according to the refractive index (> 1) of the liquid. It can be made larger and the resolution can be improved.

However, simply exchanging the objective lens from a dry system to an immersion system cannot efficiently observe the substrate in the above manufacturing process. In order to perform the observation efficiently, a mechanism for supplying a liquid between the tip of the immersion objective lens and the substrate and a mechanism for recovering the liquid are necessary. A device for arrangement is also necessary.
An object of the present invention is to provide a simple microscope observation apparatus capable of efficiently observing a substrate by a liquid immersion method.

The microscope observation apparatus according to claim 1, a support means for supporting a substrate to be observed, an immersion objective lens, a supply means for supplying a liquid between the tip of the objective lens and the substrate, Recovery means for recovering the liquid from the substrate. The supply means and the recovery means are arranged in the vicinity of the tip of the objective lens, and at least one pipe used for the supply and recovery of the liquid, and the supply and recovery of the liquid via the pipe Share a reciprocating pump for the said supply means and said recovery means share a first switching unit for connecting / interrupting a first path between the pipe and the pump, said supply means, said In addition to having a supply section for supplying liquid, the second switching section for connecting / blocking a second path between the supply section and the pump is provided, and the recovery means has a discharge section for discharging the liquid. And a third switching unit for connecting / blocking a third path between the discharge unit and the pump, wherein the first switching unit, the second switching unit, and the third switching unit are 1 path, the second path, and the third path Among those set to selectively connect state any one.

Invention according to claim 2, in the microscope observation system according to claim 1, before Symbol supply means by moving the movable member of the reciprocating pump in a predetermined direction, the supply of the liquid through the pipe The recovery means recovers the liquid via the pipe by moving the movable member in a direction opposite to the predetermined direction.

According to a third aspect of the present invention, in the microscope observation apparatus according to the second aspect, the moving speed V1 of the movable member when the supply means supplies the liquid, and the recovery means recovers the liquid. The moving speed V2 of the movable member satisfies the following expression (1).
V1 <V2 (1)
According to a fourth aspect of the present invention, in the microscope observation apparatus according to the second or third aspect, the supply unit and the recovery unit connect / connect a first path between the pipe and the reciprocating pump. The supply unit has a supply unit for supplying liquid, and has a second switch unit for connecting / blocking a second path between the supply unit and the reciprocating pump. The recovery means has a discharge portion for discharging the liquid, and has a third switching portion for connecting / blocking a third path between the discharge portion and the reciprocating pump, and the first switching portion The second switching unit and the third switching unit are configured to set only one of the first route, the second route, and the third route to a connected state.

According to a fourth aspect of the present invention, in the microscope observation apparatus according to any one of the first to third aspects, when the liquid is recovered from the substrate, a relative relationship between the support means and the objective lens is obtained. It further includes drive means for narrowing the interval .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, the microscope observation apparatus 10 of the present embodiment includes a stage (11, 12) that supports a substrate 10A to be observed, an immersion observation unit (14, 15), and a liquid 20 as an immersion medium. And a mechanism (17, 18, 51 to 58) for supplying / recovering water. Although not shown, the microscope observation apparatus 10 is also provided with a control unit, a mechanism for automatically transporting the substrate 10A, a TTL autofocus mechanism, and the like. The substrate 10A is a semiconductor wafer or a liquid crystal substrate. The microscope observation apparatus 10 is used for observation (appearance inspection) of defects or foreign matters in a circuit pattern formed on the substrate 10A in a manufacturing process of a semiconductor circuit element or a liquid crystal display element. The circuit pattern is, for example, a resist pattern.

The stage (11, 12) will be described. The stage (11, 12) includes a sample stage 11 and an XYZ stage 12. The sample stage 11 is supported by an XYZ stage 12 so as to be movable in the vertical direction and movable in a horizontal plane. The substrate 10A is conveyed from, for example, a developing device and placed on the upper surface of the sample stage 11, and is fixedly supported by, for example, vacuum suction.
The XYZ stage 12 moves the sample stage 11 in the vertical direction when the substrate 10A is focused. The focusing operation is performed by a control unit (not shown) using an autofocus mechanism. Further, the XYZ stage 12 moves the sample stage 11 within the horizontal plane when positioning a predetermined observation point of the substrate 10A within the visual field of the immersion observation unit (14, 15). The base member of the XYZ stage 12 is fixed to the main body of the microscope observation apparatus 10.

  The immersion observation unit (14, 15) will be described. The immersion observation unit (14, 15) is provided with an objective lens 14 and an eyepiece lens 15. The objective lens 14 and the eyepiece lens 15 are each fixed to the main body of the microscope observation apparatus 10. The objective lens 14 is an immersion type objective lens so that the aberration of the optical system is corrected when the space between the tip (lower surface) and the substrate 10A is filled with the immersion medium (liquid 20). Designed. The tip of the objective lens 14 is a part that touches the liquid 20. Further, an illumination light source (not shown) is provided inside the main body of the microscope observation apparatus 10 (between the objective lens 14 and the eyepiece lens 15). The observation wavelength is, for example, a visible region or an ultraviolet region.

Note that when an illumination light source having a wavelength in the ultraviolet region is used, observation from the eyepiece lens 15 is not possible.
In the immersion observation unit (14, 15), an enlarged image (pattern image) of the substrate 10A is formed at the visual field position of the eyepiece lens 15, and the substrate 10A is observed by this image. Further, the numerical aperture of the objective lens 14 can be made larger than “1” according to the refractive index (> 1) of the liquid 20 filling the space between the tip of the objective lens 14 and the substrate 10A. Compared with the numerical aperture of the objective lens ≦ 1), the resolution can be improved reliably.

  Incidentally, the resolution is expressed as “resolution = k × λ / NA” using the numerical aperture NA of the objective lens 14, the observation wavelength λ, and the constant k. When discussing the resolution between two lines, the value of the constant k is normally “0.5”. The numerical aperture NA of the objective lens 14 is expressed as “NA = n × sin θ” using the opening angle θ of the objective lens 14 and the refractive index n of the medium between the objective lens 14 and the substrate 10A. The Thus, the resolution decreases (increases) in inverse proportion to the increase in the refractive index n between the objective lens 14 and the substrate 10A.

  The mechanism (17, 18, 51 to 58) for supplying / recovering the liquid 20 will be described. The mechanism (17, 18, 51 to 58) includes nozzles 17, 18, a pipe 51 connected to the nozzles 17, 18, and a three-position switching type electromagnetic valve 52 disposed in the middle of the pipe 51. A liquid tank 53 for storing new clean liquid 5A, a reciprocating pump (54 to 57), and a pipe 58 for discharging to the outside of the apparatus are provided. The nozzles 17 and 18 correspond to “piping” in the claims.

  The nozzles 17 and 18 are integrally fixed around the objective lens 14, and their tips are arranged near the tip of the objective lens 14. The nozzles 17 and 18 are both shared by the mechanism for supplying the liquid 20 and the mechanism for recovering, and are used as a discharge nozzle when the liquid 20 is supplied and used as a suction nozzle when the liquid 20 is recovered. As described above, by sharing the nozzles 17 and 18, the narrow space around the objective lens 14 can be effectively used, and the discharge nozzle and the suction nozzle can be efficiently arranged, and the apparatus can be simplified. .

  The reciprocating pump (54 to 57) includes a cylinder 54, a piston 55, a feed screw 56, and a motor 57. The piston 55 is coupled to a feed screw 56 that converts the power of the motor 57 into linear motion, and can reciprocate at an arbitrary speed. The moving speed of the piston 55 can be adjusted according to the rotational speed of the motor 57. The moving direction of the piston 55 corresponds to the rotating direction of the motor 57.

The cylinder 54 is connected to the liquid tank 53 via the first path of the solenoid valve 52, is connected to the nozzles 17 and 18 via the second path, and is connected to the discharge pipe 58 via the third path. Corresponding to the “discharge section”). However, in the solenoid valve 52, the three paths are not opened at the same time, and only one of them is always opened and set to the connected state.
The electromagnetic valve 52 connects / blocks the path between the cylinder 54 and the liquid tank 53 in the first path (corresponding to “second switching unit” in the claims). The electromagnetic valve 52 connects / blocks the path between the cylinder 54 and the nozzles 17 and 18 in the second path (corresponding to “first switching portion” in the claims). Further, the solenoid valve 52 connects / blocks the path between the cylinder 54 and the discharge pipe 58 in the third path (corresponding to “third switching portion” in the claims).

Then, the piston 55 (corresponding to the “movable member” in the claims) is moved to the right in the drawing in a state where the first path is opened in the electromagnetic valve 52 and the cylinder 54 and the liquid tank 53 are actually connected. As a result, the liquid 5A inside the liquid tank 53 can be introduced into the cylinder 54 (liquid 5B).
Further, in the state where the second path is opened in the solenoid valve 52 and the cylinder 54 and the nozzles 17 and 18 are actually connected, the piston 5 is moved in the left direction in the drawing, whereby the liquid 5B inside the cylinder 54 is obtained. Can be delivered to the nozzles 17 and 18. The delivered liquid 5B is discharged from the tips of the nozzles 17 and 18, and reaches between the tip of the objective lens 14 and the substrate 10A (liquid 20). That is, the liquid 20 is supplied through the nozzles 17 and 18 by the reciprocating pumps (54 to 57). The supply of the liquid 20 is automatically performed by a control unit (not shown) before the immersion observation.

  The amount of the liquid 5B delivered from the cylinder 54 to the nozzles 17 and 18 (that is, the supply amount V of the liquid 20) is equal to the product of the cross-sectional area S of the cylinder 54 and the movement amount X of the piston 55 (V = S · X). The amount of movement of the piston 55 can be arbitrarily adjusted. Further, the supply speed of the liquid 20 can be arbitrarily adjusted according to the moving speed of the piston 55. In this case, the moving speed V1 of the piston 55 is preferably set to be slow so that the liquid 20 does not scatter from the tips of the nozzles 17 and 18.

  If the supply amount V of the liquid 20 can be made appropriate, the liquid 20 forms “droplets” between the tip of the objective lens 14 and the substrate 10A due to surface tension. Here, the shape of the surface of the liquid 20 supplied between the tip of the objective lens 14 and the substrate 10A will be described with reference to FIG. The surface of the liquid 20 is an exposed surface between the tip of the objective lens 14 and the substrate 10A. When the supply amount V of the liquid 20 is appropriate, the surface shape of the liquid 20 tends to be a sphere having the smallest area due to the surface tension. Therefore, the liquid 20 slightly protrudes from the tip of the objective lens 14 according to the surface tension. In FIG. 2, the diameter of the tip of the objective lens 14 is indicated by “d”, and the protrusion width of the liquid 20 from the tip of the objective lens 14 is indicated by “A”.

  In the microscope observation apparatus 10 of the present embodiment, for example, the supply amount V of the liquid 20 that can form “droplets” by surface tension is calculated in advance, and in order to realize this appropriate supply amount V, the cylinder 54 Using the cross-sectional area S, the movement amount X (= V0 / S) of the piston 55 is calculated. For the calculation of the supply amount V, the diameter d of the tip of the objective lens 14, the working distance δ of the objective lens 14, and the protrusion width A from the tip of the objective lens 14 are used.

  Further, in order to realize the movement amount X of the piston 55 calculated in advance (that is, to realize an appropriate supply amount V of the liquid 20), the motor 57 is rotated to move the feed screw 56, and the movement amount of the piston 55 is changed. It is preferable to precisely control X. As a control method, a method of performing open loop control using a stepping motor as the motor 57 and a method of performing closed loop control using a rotary encoder or a linear encoder are conceivable.

  On the other hand, when the liquid 20 is supplied, the second path of the solenoid valve 52 is opened and the cylinder 54 and the nozzles 17 and 18 are actually connected, and the piston 55 is supplied with the liquid 20. When moved in the reverse direction (right direction in the figure), the liquid 20 between the tip of the objective lens 14 and the substrate 10A can be sucked together with the surrounding air through the nozzles 17 and 18. The sucked liquid 20 is guided into the cylinder 54 (waste liquid 5B). Thus, the liquid 20 is recovered by the reciprocating pump (54 to 57) through the nozzles 17 and 18. Recovery of the liquid 20 is automatically performed by a control unit (not shown) after immersion observation.

The suction speed of the liquid 20 by the reciprocating pump (54 to 57) can be arbitrarily adjusted according to the moving speed of the piston 55. In this case, the moving speed V2 of the piston 55 is preferably set to a speed higher than the moving speed V1 when the liquid 20 is supplied (V1 <V2).
The behavior of the liquid 20 at the time of drawing by the reciprocating pumps (54 to 57) is shown in FIGS. Before the start of drawing, as shown in FIG. 3A (similar to FIG. 2), the shape of the surface (exposed surface) of the liquid 20 is approximately spherical. When drawing-in is started, it gradually becomes as shown in FIG. 3B, and the amount of protrusion due to surface tension disappears. Finally, as shown in FIG. 3C, the central portion between the tip of the objective lens 14 and the substrate 10A is thinned and cut off.

For this reason, the suction speed (moving speed V2 of the piston 55) by the reciprocating pumps (54 to 57) is sucked from the nozzles 17 and 18 rather than the amount of air leakage caused by the distance between the tip of the objective lens 14 and the substrate 10A. The conditions are preferably such that the amount increases. This is clear from Bernoulli's theorem.
Further, during the suction operation (timing shown in FIG. 3B or FIG. 3C), the XYZ stage 12 is controlled to raise the sample table 11 slightly (within ≦ δ), and the objective lens 14 The distance between the tip of the substrate and the substrate 10A may be reduced, and the amount of air leakage resulting from this distance may be reduced. In this case, the liquid 20 remaining on the substrate 10A can be effectively sucked.

Further, in the state where the third path is opened in the solenoid valve 52 and the cylinder 54 and the discharge pipe 58 are actually connected, the piston 55 is moved in the left direction in the drawing, thereby The waste liquid 5B (and air) can be sent to the discharge pipe 58. The discharged waste liquid 5B is discharged out of the apparatus through the pipe 58.
In the present embodiment, for example, pure water is used as the liquid 20 of the immersion medium. Pure water can be easily obtained in large quantities in a semiconductor manufacturing process or the like. Further, since there is no adverse effect on the photoresist on the substrate 10A, a nondestructive inspection of the substrate 10A can be performed. In addition, pure water has no adverse effect on the environment, and since the content of impurities is extremely low, an effect of cleaning the surface of the substrate 10A can be expected. The pure water used in the semiconductor manufacturing process is generally called “ultra pure water”. This is more pure than what is commonly referred to as “pure water”. Also in this embodiment, it is more preferable to use ultrapure water.

  Of the above mechanisms (17, 18, 51 to 58), the nozzles 17 and 18 are made of stainless steel (stainless steel formed by electrolytic polishing to form an oxide film) steel or Teflon (registered trademark) (fluororesin PTFE). , The sealing material is made of Teflon (registered trademark) or fluororubber, all the pipes 51, 58,... Are made of stainless steel or Teflon (registered trademark), and all other surfaces (piston 55 or The inner surface of the liquid tank 53) is preferably made of the same material. These stainless steel and Teflon (registered trademark) have the advantage that they are chemically stable and impurities (for example, metal ion-based materials) are difficult to be mixed into the liquid 20.

  In order to monitor the remaining amount of the liquid 5A in the liquid tank 53, a float sensor (liquid level gauge), an upper limit level sensor, and a lower limit level sensor are mounted on the liquid tank 53, and the output of each sensor is confirmed on the operation PC screen. It is preferable to be able to do this. Furthermore, it is preferable to display a warning display on the operation PC screen when the liquid 5A reaches the position of the lower limit level sensor.

Next, the observation operation of the substrate 10A in the microscope observation apparatus 10 of the present embodiment will be described. The observation operation of the substrate 10A is automatic control by a control unit (not shown). The electromagnetic valve 52 of the mechanism (17, 18, 51 to 58) for supplying / recovering the liquid 20 is in a state where the second path is opened in the initial state, and the cylinder 54 and the nozzles 17, 18 are actually connected. Yes.
Prior to the start of the observation operation of the substrate 10A, the control unit calculates an appropriate supply amount V of the liquid 20 (that is, an amount capable of forming “droplets” by surface tension), and realizes this supply amount V. A necessary movement amount X (= V0 / S) of the piston 55 is calculated as a “target value”.

  Then, after the movement amount X of the piston 55 is calculated, the observation operation of the substrate 10A is started. First, the substrate 10 </ b> A to be observed is transferred to the stage (11, 12) and fixed to the upper surface of the sample stage 11. Next, the XYZ stage 12 is controlled, and the sample stage 11 is moved in the horizontal plane so that a predetermined observation point of the substrate 10A is positioned in the field of view of the objective lens 14. Further, the sample stage 11 is moved in the vertical direction, and the distance between the tip of the objective lens 14 and the substrate 10A becomes a substantially desired distance (the working distance δ of the objective lens 14) using an unillustrated autofocus mechanism. Move to position.

  Thereafter, the supply of the liquid 20 is started. That is, the motor 57 of the reciprocating pump (54 to 57) is rotated to move the feed screw 56, and the piston 55 is moved leftward in the figure (speed V1). Due to the movement of the piston 55, the liquid 5B inside the cylinder 54 is sent to the nozzles 17 and 18 through the electromagnetic valve 52 (second path) and the pipe 51, and reaches between the tip of the objective lens 14 and the substrate 10A. (Liquid 20). Further, the movement amount X of the piston 55 is precisely controlled, and the motor 57 is stopped when the movement amount X coincides with the “target value” calculated in advance. That is, the supply of the liquid 20 is stopped.

In this way, the amount of liquid 20 supplied between the tip of the objective lens 14 and the substrate 10A is obtained by making the movement amount X of the piston 55 coincide with the “target value” calculated in advance and performing precise quantitative discharge. Can be an amount capable of forming “droplets” by surface tension. The liquid 20 at this time is, for example, in the state shown in FIG.
When the supply of the liquid 20 is completed, the liquid crystal observation becomes possible after performing precise focusing by the autofocus mechanism. In this state, the observer performs immersion observation of the observation point of the substrate 10 </ b> A through the eyepiece lens 15. Since the supply amount V of the liquid 20 is appropriate and no bubbles remain between the tip of the objective lens 14 and the substrate 10A, a clear image of the observation point of the substrate 10A can be observed.

  Upon receiving an instruction “immersion observation end” from the observer, the control unit starts collecting the liquid 20. That is, the motor 57 of the reciprocating pump (54 to 57) is rotated to move the feed screw 56, and the piston 55 is moved rightward in the drawing (speed V2). As the piston 55 moves, the liquid 20 is recovered from between the tip of the objective lens 14 and the substrate 10A via the nozzles 17 and 18. That is, no “droplet” is left on the substrate 10A.

  After collecting the liquid 20, the path of the electromagnetic valve 52 is switched (that is, the third path is opened), and the waste liquid 5B inside the cylinder 54 is discharged out of the apparatus. Further, the path of the electromagnetic valve 52 is switched (that is, the first path is opened), and the clean liquid 5 A in the liquid tank 53 is taken into the cylinder 54. Further, after the intake, the path of the electromagnetic valve 52 is switched again so that the cylinder 54 is connected to the discharge nozzle 17.

When there is another observation point in the substrate 10A, the above operation is repeated. When immersion observation is completed for all observation points, the substrate 10A is recovered from the stages (11, 12), and the observation operation of the substrate 10A is completed.
As described above, in the microscope observation apparatus 10 of the present embodiment, since the common nozzles 17 and 18 that function as the discharge nozzle or the suction nozzle are provided, a narrow space around the objective lens 14 can be used effectively, and the apparatus can be simplified. Is achieved. Therefore, the substrate can be efficiently observed by the immersion method using the simple microscope observation apparatus 10.

Further, in the microscope observation apparatus 10 of the present embodiment, since the liquid 20 can be supplied and recovered only by reversing the moving direction using a common reciprocating pump (54 to 57), the apparatus can be simplified and miniaturized. Is planned.
Furthermore, in the microscope observation apparatus 10 of the present embodiment, the three-position switching type electromagnetic valve 52 is used, and the supply / recovery of the liquid 20 to the substrate 10A and the common cylinder 54 can be performed only by switching the path of the electromagnetic valve 52. Since the waste liquid 5B collected inside can be discharged and a new clean liquid 5A can be introduced, the same new liquid 20 can be supplied to all the observation points of the substrate 10A, and good immersion observation is possible. It becomes.

  In the microscope observation apparatus 10 of the present embodiment, an appropriate supply amount V of the liquid 20 is calculated in advance, and the movement amount X (= V0 / S) of the piston 55 necessary to realize the supply amount V is calculated. Since it is calculated as a “target value” and the movement amount X of the piston 55 is made to coincide with the “target value” in actual supply control, an appropriate amount of liquid 20 capable of forming “droplets” can be supplied by surface tension. Therefore, a clear image of the substrate 10A can be observed through the minimum liquid 20 necessary for the immersion observation of the substrate 10A, and all the liquids 20 are efficiently removed from the substrate 10A after the immersion observation of the substrate 10A. Can be recovered.

Furthermore, in the microscope observation apparatus 10 of the present embodiment, the liquid 20 is automatically supplied and collected during immersion observation, so that there is almost no burden on the operator and the substrate 10A can be observed with high throughput. it can.
(Modification)
In the above-described embodiment, an example in which the number of shared nozzles 17 and 18 is two has been described, but the present invention is not limited to this. The number of shared nozzles may be one or more than three. Further, it is not necessary to share all the nozzles provided in the apparatus, and at least one nozzle may be shared and the remaining nozzles may be used individually (as discharge nozzles or suction nozzles). For example, as shown in FIG. 4, four nozzles 61 to 64 are arranged around the objective lens 14, of which only one nozzle 61 is shared and the remaining nozzles 62 to 64 are suction nozzles. Conceivable.

Further, in the above-described embodiment, by switching the path of the three-position switching type electromagnetic valve 52, in addition to supplying / recovering the liquid 20 to / from the substrate 10A, discharging the waste liquid 5B and introducing new clean liquid 5A. However, the present invention is not limited to this. When it is assumed that the same liquid 20 is reused, the electromagnetic valve 52 may be omitted.
Further, in the above-described embodiment, the example in which the liquid 20 is supplied and recovered using the shared reciprocating pump (54 to 57) has been described, but the present invention is not limited to this. The present invention can also be applied to the case where the pump for supplying the liquid 20 and the pump for recovery are separately configured. In this case, a reciprocating pump (54 to 57) similar to the above can be used as each pump. Further, a vacuum pump or a vacuum device in the factory can be used as the recovery pump, and it is preferable to provide a waste liquid storage tank and a water removal filter in the preceding stage.

  In the above-described embodiment, the example in which the liquid 20 is supplied / collected for each observation point of the substrate 10A has been described. However, the present invention is not limited to this. When the distance to the next observation point on the substrate 10A is short, the XY stage 13 (that is, the substrate 10A) may be moved without collecting the liquid 20 supplied to the current observation point. When the surface of the substrate 10A has a certain degree of hydrophobicity and the tip of the objective lens 14 has a certain degree of hydrophilicity, the liquid 20 tends to continue to adhere to the objective lens 14 side. Therefore, even if the XY stage 13 (that is, the substrate 10A) is moved, the liquid 20 can be attached to the tip of the objective lens 14, and the same liquid 20 is used when the next observation point is reached. Can observe.

  Furthermore, in the above-described embodiment, the immersion objective lens 14 is fixed to the main body of the microscope observation apparatus 10, but the present invention is not limited to this. The immersion type objective lens 14 may be attached to the revolver so that it can be switched to another dry type objective lens. In the embodiment described above, the nozzles 17 and 18 are integrally fixed around the objective lens 14, but may be externally attached. Further, in the above-described embodiment, the example in which the piston 55 is driven by the motor 57 and the feed screw 56 has been described, but an air cylinder may be provided instead. In this case, it is preferable to provide limit sensors at both ends of the stroke of the air cylinder.

  In the above-described embodiment, an example of immersion observation using the eyepiece 15 has been described. However, the present invention is not limited to this. An imaging element and a monitor may be provided, and immersion observation may be performed using a display image on the monitor. Both immersion observation with the eyepiece 15 and immersion observation with the imaging device and the monitor may be performed, or either one may be performed. However, when the observation wavelength is in the ultraviolet region, it is preferable to omit the eyepiece and provide an image sensor and a monitor. Moreover, when making an observation wavelength into an ultraviolet region, it is preferable to fill the inside of the main body of the microscope observation apparatus 10 with nitrogen. The optical path between the objective lens 14 and the substrate 10A is not filled with nitrogen, but since the observation is performed with ultraviolet light after the liquid 20 is supplied, the ultraviolet light does not cause a photochemical reaction with the surrounding air (oxygen). Absent.

  Furthermore, in the above-described embodiment, for example, pure water is used as the liquid 20 (water immersion system), but the present invention is not limited to this. In addition, oil (for example, immersion oil or silicon oil) having a higher refractive index than pure water may be used as the liquid 20 (oil immersion system). In this case, in order to move the XY stage 13 (that is, the substrate 10A) while adhering the liquid 20 to the tip of the objective lens 14, the surface of the substrate 10A has a certain degree of hydrophilicity, and the tip of the objective lens 14 has a certain degree of hydrophobicity. It is preferable to have sex.

In addition, a liquid having a surface tension smaller than that of pure water (for example, a liquid to which a surfactant is added, an alcohol, or a mixture of these and pure water) can be used as the liquid 20. In this case, even when the circuit pattern of the substrate 10A is fine, the liquid 20 can be reliably infiltrated into the recesses of the circuit pattern and can be observed well.
Furthermore, in the above-described embodiment, the liquid tank 53 is used as a means for supplying pure water. However, pure water may be supplied using a pure water production apparatus or the like.

It is a side view which shows the whole structure of the microscope observation apparatus 10 of this embodiment. 3 is a side view illustrating the shape of a liquid 20. FIG. It is a side view which shows the behavior of the liquid 20 at the time of drawing-in with a reciprocating pump (54-57). It is a top view explaining the other example of arrangement of a nozzle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Microscope observation apparatus 10A Board | substrate 11 Sample stand 12 XYZ stage 14 Objective lens 15 Eyepiece 17, 18 Nozzle 20 Liquid 51, 58 Piping 52 Solenoid valve 53 Liquid tank 54 Cylinder 55 Piston 56 Feed screw 57 Motor

Claims (4)

Supporting means for supporting the substrate to be observed;
An immersion objective lens;
Supply means for supplying a liquid between the tip of the objective lens and the substrate;
A recovery means for recovering the liquid from the substrate;
The supply means and the recovery means are arranged in the vicinity of the tip of the objective lens, and at least one pipe used for the supply and recovery of the liquid, and the supply and recovery of the liquid via the pipe Share with reciprocating pumps
The supply unit and the recovery unit share a first switching unit that connects / blocks a first path between the pipe and the pump,
The supply unit includes a supply unit that supplies the liquid, and a second switching unit that connects / blocks a second path between the supply unit and the pump,
The recovery means has a discharge part for discharging the liquid, and has a third switching part for connecting / blocking a third path between the discharge part and the pump,
The first switching unit, the second switching unit, and the third switching unit selectively set any one of the first route, the second route, and the third route to a connected state. A microscope observation apparatus characterized by that. In the microscope observation apparatus according to claim 1 ,
Before Symbol supply means by moving the movable member of the reciprocating pump in a predetermined direction, it performs the supply of the liquid through the pipe,
The microscope observing apparatus, wherein the recovery means recovers the liquid via the pipe by moving the movable member in a direction opposite to the predetermined direction. The microscope observation apparatus according to claim 2,
The moving speed V1 of the movable member when the supplying means supplies the liquid and the moving speed V2 of the movable member when the collecting means collects the liquid satisfy the following expression (1). V1 <V2 (1)
A microscope observation apparatus characterized by that. In the microscope observation apparatus according to any one of claims 1 to 3,
A microscope observation apparatus, further comprising a driving unit that narrows a relative distance between the support unit and the objective lens when the liquid is recovered from the substrate.

Images