CN114063274A

CN114063274A - Scanning depletion laser microscope

Info

Publication number: CN114063274A
Application number: CN202110825071.5A
Authority: CN
Inventors: 霍素国
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-07-31
Filing date: 2021-07-21
Publication date: 2022-02-18
Also published as: GB202012000D0; GB2597748A

Abstract

Two types of Scanning Depletion Laser (SDL) microscopes have been proposed to obtain a depleted nanobeam consisting of an airy disk and an inverse amplitude ring for obtaining high resolution nanoscale images, nanoscale lithography, and nanoscale optical information storage. The first proposed type of SDL (SDL-1) employs a 1800 phase shift lens unit consisting of an airy disk lens and a relatively 1800 phase shift ring lens to form a depleted nanobeam on the sample surface after passing through the laser beam. The second proposed type of SDL (SDL-II) has employed two 1800 phase shifted laser cross beams to pass through the ring lens unit and the airy disc lens of the zero phase shift lens unit, respectively, to form a depleted nanobeam on the sample surface. A solution and a gas may also be filled between the lens unit and the sample to further reduce the size of the nanobeam, respectively. Several lens units have been proposed, and a plurality of phase shifting lens units have also been proposed to speed up the process.

Description

Scanning depletion laser microscope

Cross Reference to Related Applications

The present application claims priority and benefit to uk application No. gb2012000.2 entitled "Scanning deletion Laser Microscope" filed on 31/7/2020, which is hereby incorporated by reference in its entirety for all purposes.

Technical Field

The present invention relates to the field of Scanning Depletion Laser (SDL) microscopy, and more particularly to SDL microscopes for obtaining nanoscale lithography, high resolution nanoscale images, and nanoscale optical information storage.

Background

Nanometer-scale resolution optical images have been obtained using an excitation emission depletion (STED) fluorescence microscope, which acquired the nobel prize in 2014. The inventive STED has revolutionized optical image resolution by breaking through the optical diffraction limit, but its application is limited to staining molecular images. Nanoscale images can also be obtained using a scanning near-field microscope (SNM) having a very sharp tip with a nanoscale aperture. SNM has no limitations for imaging any particular sample, but its working distance is only a few nanometers, leading to other problems such as nano-scale pore contamination and overheating as light intensity increases.

Photolithography is a key process for the mass production of circuits, chips and devices, while the lithography machines used to make nanoscale patterns on photoresists are a necessary process for the success of the micro/nano electronics industry. Now, it is claimed that line widths made by extremely expensive lithography machines have been sought to be reduced to sub-10 nm. However, such optical lithography machines are too expensive to be affordable by many research institutions and even by many industries. Electron Beam Lithography (EBL) is commonly used for nanoscale research in universities, institutions, or even in industrial development (R & D) and small-scale production, as EBL is relatively affordable. However, EBLs have many limitations in fabricating nanoscale patterns, such as no magnetic stray field from the sample and the electron charge has to be grounded. In particular, EBL is too slow to be used for large scale production in industry. Furthermore, even with EBL, sub-10 nm resolution presents a significant challenge. Scanning laser direct write machines have also been invented and used for optical lithography, but are limited to sub-micron line widths.

Information storage presents one of the key components of information technology and people's daily life. Currently, magnetic storage and semiconductor flash memory are still the two main ways of information storage. Optical storage has been overwhelmed due to the low areal storage density resulting from wavelength limitations. However, optical storage uses a non-contact storage method and does not have viruses during data transfer, as compared to magnetic storage and semiconductor flash memory. Thus, optical storage may replace removable magnetic hard disk drives or removable flash memory drives as long as the areal storage density can be matched to that in magnetic storage and flash memory, because optical storage is free of virus transmission, more economical and more reliable through the use of optical disks, because optical storage disks are simply recording media without any complicated machinery or circuitry.

The present disclosure proposes two types of high resolution Scanning Depletion Laser (SDL) microscopes that do not require staining or staining of the sample as required in STED microscopes, and can also overcome most of the problems in SNM. The first type of SDL microscope (SDL-I) uses the proposed phase shift lens cell, which consists of 0⁰Phase shift lens and phase shifter 180⁰A phase shift lens to generate an airy disk beam and a reverse amplitude ring beam, respectively, after the laser beam passes through the lens unit to form a nano-beam on the sample surface by overcoming optical wavelength limitations. The phase shift lens unit is composed of a central sub-wavelength transparent circular lens and at least three sub-wavelength transparent circular lenses surrounding a ring lens having a relative 180 DEG in comparison with the central lens⁰The phase shift of (2). The laser beam passing through the central lens will produce an airy disk and pass through the other periphery 180⁰The laser beam of the phase shift lens will produce a series of airy spots that will form a ring-shaped laser beam pattern having an opposite amplitude compared to the amplitude from the central airy spot. Similar to the case in the STED fluorescence microscope, the overlapping of the annular and central airy spots enables the formation of a nanoscale beam spot, a nanobeam, on the surface of the sample. The second type of SDL microscope (SDL-II) employs two 180⁰Phase-shifted laser cross beams, each passing through 0 composed of a sub-wavelength transparent circular lens⁰A phase shifting lens unit and at least three small transparent sub-wavelength circular lenses in a ring shape to produce an airy disk beam and an opposite amplitude ring beam, respectively, to construct a nanoscale beam at a crossover beam point on the sample surface by overcoming optical wavelength limitations.

The nanobeam produced by the SDL-I microscope or SDL-II microscope can then be used to image the sample by scanning the sample with the beam (stage) or a phase shifting lens unit. A small size aperture may be used to block stray light. A detector similar to that used in SNM may be used to collect the reflected beam from the sample. One design may be an annular photodetector to collect the nanobeam reflected by the sample. Such an SDL microscope can achieve better resolution than the resolution of about 20nm claimed by STED fluorescence microscopy, because it can use ultrashort wavelengths of light, such as a typical ArF excimer 195nm wave laser, which has a wavelength shorter than half the shortest wavelength of visible light of about 400nm used in STED fluorescence microscopy.

The proposed Scanning Depletion Laser (SDL) microscope may have many applications such as nanoscale imaging, nanoscale lithography, and also high areal density optical storage. Moreover, a typical laser beam spot may be on the micrometer to millimeter scale and may cover multiple phase-shifting lens cells, and the multiple phase-shifting lens cells may greatly accelerate the process.

Compared to STED fluorescence microscopy, the proposed SDL microscope can work on all materials and does not require staining or staining of the sample. Compared to a scanning near-field microscope, the nanobeam laser microscope does not require the use of a 50nm nanoscale aperture, which can be easily contaminated, and can have a relatively large working distance. In particular, the nanobeam in an SDL microscope can be much smaller than 50nm, down to sub-10 nm.

SDL microscopy can be used for nanobeam lithography. The proposed SDL microscope can also be used like a normal laser writer, but can be reduced to nanoscale resolution due to the use of the proposed phase-shifting lens unit to produce a nano-beam probe. In contrast to EBL, SDL nanobeam laser microscopy does not require conductive and non-magnetic samples. Also, multiple nanobeams may speed up the process. SDL microscopes are also much cheaper than any nano-scale lithography machine.

Another application of SDL microscopy is information storage. Currently, most information storage uses magnetic hard disk drive storage and semiconductor flash memory. Laser optical storage is now rarely used due to the low areal density of optical storage. If a 20nm nanobeam is used (which may match or even be higher than the storage areal density in currently available magnetic or flash memory storage), the proposed SDL microscope can greatly increase the areal density to 1Tb per square inch. Furthermore, laser storage is contactless storage, which may prevent any virus transmission — a common problem in using USB. Therefore, it is desirable that nano-beam laser storage can replace current removable USB drives because there is no virus problem to transfer through storage and optical discs are also much cheaper.

Disclosure of Invention

Two types of Scanning Depletion Laser (SDL) microscopes have been proposed for nanoscale images, nanoscale optical lithography, and high areal density nanoscale optical storage. SDL of the first type (SDL-1) uses by 0⁰Phase shift lens assembly 180⁰A phase shift lens unit composed of phase shift lens units to realize a nano-scale beam by overcoming optical wave formation limitation. In one embodiment, the phase shift lens unit is composed of an Airy-patch lens having a circular center lens with a subwavelength dimension and at least three opposing 180 s surrounding the Airy-patch lens⁰Phase-shifted airy disk lenses or ring lenses. After the laser beam passes through the phase shift lens unit, the airy disk is formed by the central circular lens and by the surrounding 180⁰The phase-shifting lens produces a ring shape of opposite amplitude formed by a series of airy spots to form a depletion nanometer beam spot on the sample surface because the overlapping portion of the airy spots and the opposite amplitude rings is 180 degrees in terms of their amplitudes⁰The phase shifts can cancel each other out. To overcome the extremely complicated manufacture of the first embodiment set forth above, in the second embodiment, two 180 s⁰Phase shifting lenses to less than but close to 180 deg.f⁰At two angles of 180⁰Made on phase-shifting glass and which is also capable of converting the laser beam into 0⁰Phase shifting Airy spots and 180⁰The two intersecting beams of the ring are phase shifted to form a depleted nanobeam at the intersection of the two beams. In a third embodiment, a hemispherical lens (or hemispherical shell lens) is composed of a nano-sized lens unit capable of generating a ring beam at its top pole andseveral nanometer sized opposites 180 symmetrically disposed about the top pole on the latitudinal circumference of the hemispherical lens⁰A phase shift lens, the top nano-sized lens unit for generating a ring-shaped beam, the opposite 180⁰The phase shifting lens is used to produce a strong amplitude phase shift 180 which cancels its horizontal component at its beam-crossing point⁰The phase-shifted airy disk is then combined with an opposite amplitude annular beam to form a depleted nanobeam for nanoscale imaging, nanoscale lithography, and even nanoscale optical recording.

A second proposed type of SDL (SDL-II) microscope employs two opposing 180⁰The laser beam is phase shifted to produce an airy disc beam and an opposite amplitude annular beam through an airy disc lens and an annular lens, respectively, to form a depleted nanobeam at a point of intersection of the intersecting beams on the sample surface. In one embodiment, the Airy lens and the annular lens are each less than but close to 180 f⁰Two connected modes on glass at an angle. In the second embodiment, the group of airy disk lenses and the group of annular lens units are respectively arranged at symmetrical positions relative to the poles of the hemispherical shell lens unit (or hemispherical lens unit) or the spherical lens. Two 180 s may also be used in an SDL-II microscope⁰The polarized beam is shifted to cancel out the horizontal amplitude to obtain a uniform sharp synthetic depleted nanobeam. Solutions and gases can be used to fill in between the lens and the sample surface in SDL-I and SDL-II to further reduce the nanobeam size.

Multiple phase shifting lens units and multiple sources are also proposed to speed up the process. The source of the SDL will include both normal and polarized visible, UV, EV light and electromagnetic waves.

Drawings

Figure 1 shows a typical single point scanning STED microscope working principle.

Fig. 2 shows the texture for the material used in the design.

Figures 3(a) -3(d) show the orifice, airy disk and amplitude and intensity, respectively, for a sample with one airy disk, two airy disks without much overlap, two airy disks with almost one-third overlap, and two airy disks with almost two-thirds overlap.

FIGS. 4(a) and 4(b) show a lens without a phase shift mask and a lens with a 180 degree phase shift mask, respectively⁰Mask design, amplitude and intensity of the lenses of the phase shift mask.

FIGS. 5(a) and 5(b) respectively show the structure for the probe pin with 180⁰Mask design and amplitude and intensity of a single lens of a phase shift mask and two aperture lenses without a phase shift mask.

FIGS. 6(a) and 6(b) show 180 composed of the lenses of FIGS. 5(a) and 5(b), respectively⁰Design, amplitude and intensity of the phase shifting lens unit.

FIGS. 7(a) and (b) each show a cross-sectional view having a cross-sectional view of 180⁰One central nanoscale lens with phase shift and having a value of 0⁰Phase shift lens design, airy disc and amplitude of six surrounding nanoscale lenses that phase shift.

FIGS. 8(a) -8(c) show two types of nano-beam phase-shift lens cell designs for the first scanning depletion laser (SDL-I) microscope, Airy spots and amplitudes and intensities for all of the lenses shown in FIGS. 7(a) and 7(b), respectively, and a ring shape of 0⁰A center 180 surrounded by phase shifting lenses⁰A phase shifting lens.

FIGS. 9(a) -9(c) are shown at approximately, but less than, 180 deg.F, respectively⁰Two of the angular joints 180⁰A second embodiment of the SDL-I design, opposite the phase shift lens, a nanobeam formed by depletion of the airy disk and the inverted amplitude toroid and its corresponding amplitude at the intersection.

FIGS. 10(a) -10(e) show top, side, cross-sectional, beam airy disk and cross-beam hemispherical shells (or hemispheres) 180 of an SDL-I microscope⁰Corresponding amplitude of the phase shift lens design.

FIGS. 11(a) -11(c) illustrate top views of three sub-wavelength lenses of the Airy-patch lens, the annular lens, and the trimeric lens, their corresponding Airy-patches and amplitudes and intensities, respectively.

FIGS. 12(a) -12(d) show an Airy-patch lens with a ring lens, an Airy-patch lens with a trimerization lens, and an Airy-patch lens with a trimerization beam lens, respectivelyTop view, cross-sectional view, its corresponding amplitude and intensity, and two 180 s on two sub-wave lenses in each embodiment of a compact trimerization lens combined SDL-II microscope⁰The phase-shifted cross beam intersection includes the airy disk of the composite nanobeam.

Fig. 13(a) -13(c) show top plan, cross-sectional views and airy disc of two SDL-II microscope embodiments with a set of annular beam lenses and a central airy disc beam lens with a set of trimerization beam lenses plus a set of trimerization lenses, respectively, with the two beam sets being symmetric about the top pole of the hemispherical shell (or hemispherical) lens and the spherical lens.

FIGS. 14(a) and 14(b) show top and cross-sectional views, respectively, of two embodiments of the SDL-II lens shown in FIG. 13 attached to a probe cantilever frame.

Fig. 15(a) -15(c) show a top view of a cantilever having a hole near the end of the cantilever, a top view and a side view, respectively, of a spherical lens (or hemispherical shell lens) on the cantilever.

Fig. 16(a) and 16(b) show top views of a 2 x 2 lens cell on a frame and a corresponding 2 x 2 synthetic depleted nanobeam on a sample surface.

FIG. 17 shows 180 with two polarizations⁰Lens unit in phase-shifted cross-beam SDL-II microscope.

Fig. 18 shows a lens unit composed of a single airy disk beam lens and a ring beam (or trimerization) lens, respectively.

Detailed Description

Diagram 1100 is a typical single-point scanning STED microscope, where a focused excitation beam (left) is overlapped by a ring-shaped STED beam (middle), which immediately quenches the excited molecules at the periphery of the excitation point and at the same time limits the fluorescence emission to ring zero. Quenching of saturation produces a fluorescence spot at about 20nm, well below diffraction (right), which produces a sub-diffraction resolution image across the scan of the sample.

FIGS. 2(a) -2(h)200 show opaque material 21, respectively0. Glass lens material 220, partially opaque material 230, having 180⁰ Lens 240 with phase shift of 0⁰ Phase shifting lenses 250, 180⁰Phase shifted beam intensities 260, 0⁰The phase-shifted beam intensity 270 and the texture of the cantilever material 280. All materials will be used in the design of the present disclosure.

Graph 3300 shows four

lenses

310, 320, 330, 340 and their corresponding airy discs and amplitudes and intensities, respectively.

Fig. 3(a) shows top and cross-sectional views of a single subwavelength aperture lens design 310, the corresponding airy disk 316, and its amplitude and intensity 318. The lens design of 310 is effectively similar to an aperture consisting of 314 (sub-wavelength diameter D-holes) that opens on an opaque material 312. The lens is shown in top and cross-sectional views through a to b, respectively. 314 are smaller in diameter D than the laser wavelength lambda and thus obtain airy discs 316. The radius of Airy spots 316 may be expressed as

Wherein R is the radius of the Airy plaques; d is the diameter of the hole; λ is the wavelength of the light and h is the working distance of the lens to the object.

Therefore, in order to obtain a small airy spot, a small light wavelength λ, a small working distance h and a relatively large aperture D are necessary under the condition that D must be smaller than the wavelength λ in order to obtain a light diffraction pattern.

Fig. 3(b) shows the lens design of 320, 320 consisting of two identical (or nearly identical) subwavelength holes with the same diameter D (322 and 324) also made on opaque material 312; a cross-sectional view through lenses a to b; two airy discs 326, which overlap only beginning in their adjacent tails, and two corresponding beam amplitudes in the solid line, each of which shows the composite intensity of the dotted line in the gaussian distribution and 328. The composite strength shows a deep hump shape of the dotted line in 328.

FIG. 3(c) shows a lens design of 330 consisting of two more closely spaced sub-wavelength holes of the same diameter D (332 and 334), also fabricated on opaque material 312; a cross-sectional view through lenses a-b; the amplitudes of their solid lines and the composite strengths of their dotted lines in the two

airy discs

336 and 338 that overlap by about 1/3. The composite intensity shows a shallow hump shape.

Fig. 3(D) shows a lens design 340 also consisting of two more proximal subwavelength holes of the same diameter D (342 and 344) made in opaque material 312. A lens top view and a cross-sectional view through a to b; the two airy discs 346 overlap about 2/3 and two corresponding light amplitudes in solid lines, each of which shows a gaussian distribution and also shows a resultant more or less one-peak gaussian distribution in dotted lines at 348. With this further closure of both apertures, the hump complex intensity is disappointing and one peak complex intensity is obtained, although there are still two peak amplitudes. Therefore, if the two apertures are too close, it is not possible to distinguish the two beams by intensity.

FIG. 4400 illustrates two dual-beam mask lenses 410, 0, respectively⁰Phase shift lens and 420, 180⁰The design of the phase shifting lens and its corresponding amplitude and intensity.

FIG. 4(a) shows a dual beam mask lens design 410, 0⁰The phase shift lens and its corresponding amplitudes and intensities of the two beams on the sample surface. 410 consists of glass 412 coated with an opaque material 320, such as chromium (Cr) which is widely used in photomasks, and two

open holes

322 and 324 made on 320. The amplitudes of the two beams have the same phase and a slight overlap in the adjacent tails. The composite intensity shows a hump shape, which results in an almost doubled size pattern rather than two separate patterns.

FIG. 4(b) shows a dual beam mask design 420 (which is numbered 0)⁰Phase shift lens assembly 180⁰Phase shifting lens composition) and its corresponding amplitude, i.e., composite intensity, at the sample surface. 420 consists of 422 glass, 422 consists of 0⁰ Phase shift glasses 412, 180⁰ Phase shift glass 424 and also two

holes

322 and 324 made on 320, where 322 and 324 are below 412 and 424, respectively. Thus, 322 plus 412 forms 0⁰ Phase shift lensAnd 324 plus 424 form 180⁰A phase shifting lens. From 0⁰The beam amplitudes of phase-shifting

lenses

322 and 412 are still the same as in FIG. 4(a), but from 180⁰The beam amplitudes of the

phase shifting lenses

324 and 424 have been inverted. Their composite intensity then shows two well separated beam profiles, because the overlapping parts of the two opposite amplitudes quench each other. Such phase shift masks have been widely used in commercial photolithography processes to obtain well separated adjacent lines. The present disclosure will employ such shift lens techniques to obtain a narrow beam.

FIGS. 5(a) and (b)500 show 180 of 510 and 512, respectively, of FIG. 5(a)⁰Phase shifting one subwavelength aperture lens and 0 in 520 and 524 in FIG. 5(b)⁰The design and corresponding amplitude and intensity of the two subwavelength aperture phase shifts.

180 of an aperture lens 510⁰The phase shift is formed by zero phase shift glass lenses 412 and 180⁰A phase-shifting glass lens 424 and an opaque coating 310 with a subwavelength aperture 314 (just below 424). The laser beam on the lens 424 will pass through a small open aperture of 314 to form a gaussian distribution of light amplitude 512.

Two 0 s are also made on the

same glasses

412 and 424⁰Phase shifting the subwavelength aperture lens 520 but opaque coating 330 at 0⁰Two

subwavelength holes

332 and 334 are opened below the phase shift glass 412. 522 is to reduce the transfer beam amplitude to two 0 s⁰A thin coating of the phase shifting lens. 524 show the corresponding two amplitudes from 332 and 324, respectively, in solid lines, and their combined amplitude in hump dotted lines is similar to 338 in fig. 3 (c). Due to 180 in 510 and 520⁰The amplitudes shown in phase shifts, 512 and 524 are opposite. A reduced amplitude in 524 is obtained compared to the amplitude in 512 due to the use 522.

Fig. 6(a) and 6(b) show a lens design 610 and its corresponding amplitude and intensity 620, respectively, at 600, resulting from combining the two lenses of fig. 5. 610 is made of 0 coated with 522 to reduce the light amplitude⁰ Phase shift glasses 412, 180⁰ Phase shift glass 424 and

opaque layer coating

320, 320 havingThree open subwavelength holes: 332 and 334 and 314 in between. 314 at 180⁰ Phase shifting glass 424 to form 180⁰The lens is phase shifted and its corresponding amplitude is shown at a of 512. 332 and 334 are at 0⁰ Phase shift glass 422 to form 0⁰The phase shift lens, its corresponding amplitude is shown at B of 524.

Because the 314 aperture is located in the middle of the two

apertures

332 and 334, the two amplitudes of 512 and 524 will align and the combined intensity of a and B will result in a narrow beam C, shown at 620 after careful engineering. To achieve the desired beam amplitude 524, the coating 522 is used to reduce the hump amplitude to the right as described above. It is clear that the combined beam 620 shown at C has a much finer probe shape.

However, the three-aperture phase-shift lens design 610 in FIG. 6 cannot produce a circular beam spot. To obtain a symmetric nanobeam spot, at least four nanoscale holes are needed, with one central subwavelength hole surrounded by the other three subwavelength holes at each vertex of the equilateral triangle.

FIGS. 7(a) and 7(b) respectively show 180 in 700⁰ Phase shift lenses 710 and 0⁰The two lenses of phase shifting lens 720, their corresponding airy disk and amplitude and intensity distributions. 710 show 180⁰A top view of the phase shift lens and has one sub-wavelength open aperture 712. 714 is an illustration of the airy disk on the sample surface after passing the laser beam through 712. 716 shows the amplitude distribution for a to b in 714. 720 is a top view of a zero degree phase shift lens and is composed of six identical subwavelength holes 722 along the ring with equal spacing between any two adjacent holes. 724 shows a representation of an airy disk assembly with a ring shape, where each hole in 722 has its own airy disk, and six airy disks along the ring may form the ring shape of 724, and 726 is the corresponding amplitude profile intersection c and d in 724, showing zero degree phase shift hump shape intensity. 726 is lower than 716, which can be achieved by using the coating 522 on the lens of 720 to reduce the light amplitude. ab and cd can be made about the same size.

Fig. 8(a) -8(c) show two types of

lens designs

810 and 820 proposed to produce the nano-beam spots in 800, their airy discs 830, and corresponding amplitudes and intensities 840. FIG. 810 shows a top view of the lens design of 812, 812 consisting of six subwavelength holes 0⁰One 180 phase shift lens surround⁰Phase shift central subwavelength hole lens. 820 shows a top view of the lens design of 822, 822 from 0⁰One 180 phase shift ring lens surrounding⁰Phase-shifting central subwavelength aperture lenses, which can be considered as an infinite number of subwavelength circular lenses along the ring circle. The functions of 810 and 820 are similar, and 810 is considered an example for illustration. 810 is actually a combination of the two lenses of 710 and 720 in fig. 7. As discussed in FIG. 7, after passing through the laser beam, 710 will yield 180⁰Phase shifting the airy disk and 720 will produce a zero phase shift annular shape. After 710 and 720 are aligned, the airy disk 832 and the inverse amplitude ring 834 will overlap to form the nanobeam spot 836, as shown in 830. 840 with 180 produced by 710⁰The solid line of ab cross-section in the phase-shifted airy disk 832 shows the amplitude and intensity, with the amplitude shown in dashed lines and with 0 produced by 720⁰The dotted line of the cd cross section in the phase shifted ring 834 shows the intensity, and the composite nanobeam 842 is shown by the 716 and 726 intensity lines. It is apparent that 842, although reduced in amplitude, is much narrower than the original airy disk beam 716.

In design, the center lens and its surrounding lenses would have 180⁰Phase differences and they may be in the same plane or two different planes, where the central lens will be located on the top plane away from the sample surface and the surrounding lenses will be low planes near the sample surface, in order to obtain a fine composite nanobeam spot by breaking the light wave limit.

The above-described phase shift lens cell design would require a very complex fabrication process to manufacture. To overcome this, a second embodiment of a phase shift lens unit 900 is proposed and shown in fig. 9, where 0⁰Phase shift lens assembly 180⁰Phase shifting lens unit smaller than but close to 180⁰The angle of the angle is two180⁰Different phase shifts are made on the glass. The laser beam 910 and cross-section 920 of 900 are shown in fig. 9(a), respectively. 920 is positioned close to but less than 180 deg.f⁰Two 180 of angle a⁰

Phase shifting glasses

922 and 924 to pass the incident laser beam 910 through

lenses

922 and 924, respectively, to (180)⁰A) into two intersecting

beams

912 and 914, which then meet at beam intersection 916 to be depleted into a nanobeam. The corresponding airy disk of the two crossed beams is shown at 930 in FIG. 9(b), where 932 is 180 for 912⁰Phase-shifted inverted amplitude Airy spot, 934 is 0 for beam 914⁰Phase shifting rings, depleted nanobeam 916 formed at beam intersection points. In 940 of fig. 8(c), the corresponding amplitudes and

intensities

932, 934, and 916 in 930 are shown as 944, 942, and 946, respectively. It is apparent that 946 in fig. 9(c) is also a nano-sized beam probe, similar to 842 in fig. 8 (c).

In 900, the opaque layers in both

lenses

922 and 924 are coated in the bottom surface and the subwavelength holes are opened on the opaque layers. An opaque layer may also be coated on the top surface of the glass or on the top and bottom surface glass, and the subwavelength holes will be opened on the corresponding opaque layer, respectively, to form the phase shifting lens.

Clearly, two 180 of 910 made on two glasses⁰A phase-shifting lens may make manufacturing easier, but in the horizontal plane, the amplitude of either the airy disk or the annulus at the intersection is not quite uniform, which may result in some of the depleted region around the depleted nanobeam at the intersection of the two intersecting beams remaining weak light. Furthermore, the phase-shifting lens unit for obtaining the annular beam is composed of several sub-wavelength holes, and then the amplitude of the annular shape is much larger than the amplitude of the airy disk from one sub-wavelength hole. As previously mentioned, a semi-opaque coating on the ring lens unit would be required to reduce the amplitude of the ring to that in the airy disk, which would result in a weakly depleted nanobeam.

Fig. 101000 shows a third embodiment of a hemispherical shell (or hemispherical) phase shift lens. FIG. 10(a) shows a top view of 1000View 1010, in fig. 10(a), a hemispherical shell (or hemispherical) lens 1014 is placed on a holder 1012. 0⁰Phase shifting ring lens unit 1018 is located at the central pole position of 1014, and four 180 of 1016⁰The phase shifting airy disk lens is located symmetrically on the latitude circle with respect to the top pole location (also the center of 1014). Fig. 10(b) shows a side view of 1010 with a hemispherical shell lens 1014 on the

holder

1012 and 1018 on the top pole and all four 1016 symmetrically located on the latitudinal circle relative to the top pole. 1020 in fig. 10(c) is a cross-sectional view through lens 1010 shown by a and B in fig. 10(a), and the glass lens is a hemispherical shell glass 1022 in which the thickness of the glass under the 1018 annular lens is half the thickness of the glass in the other region of 1014. Thus, 1018 lens cells and four 1016 lenses on a hemispherical shell lens would have 180⁰The relative phase shift. After each 1016 lenses, laser beam 910 will be at 1018 lens units and 180⁰The phase-shifted airy disk is then converted into a ring beam. Because 1018 is located at the top pole of the hemispherical shell (or hemispherical) lens and a strong airy-disk beam with only a vertical amplitude component is obtained at the crossover beam point, a ring beam 1028 with only a vertical beam amplitude component is obtained. Since any two symmetric 1016 lenses (such as 1024 and 1026) will cancel out their horizontal components and all four airy spots from the four 1016 lenses will form a very strong airy spot at the intersection of the beams, then sum 1028 combines into a depleted nanobeam that is much stronger and has only a vertical beam component at the intersection beam point. 1030 in FIG. 10(d) shows the corresponding annular beam 1034 from 1028 after 1018 at the intersection beam point, i.e. the relative 180 at the beam intersection formed by all four Airy spots after all 1016 lenses⁰A phase-shifted airy spot 1032 and a depleted nanobeam 1036 formed by 1032 and 1034 at the beam intersection. 1040 in fig. 10(e) shows the amplitude and intensity corresponding to 1030, where the dotted line in 1042 is the intensity of the looped

beam

1034, 1044 is the inverse amplitude and intensity of the

airy spot

1032, 1046, obtained from depletion of 1042 and 1044, is the intensity of the depleted nanobeam 1036 formed by 1032 and 1034.

The height h of the hemispherical shell (or hemispherical) lens should be only a little smaller than the sphere radius r so that the nanobeam formed at the cross beam spot (center of the spherical lens) is on the surface of the photoresist used for lithography or on the surface of the sample for image and optical storage applications.

The above uses 180⁰Scanning Depletion Laser (SDL) microscope (consisting of airy disk lens) with phase shifting lens unit and opposing 180 for composing depletion nano-beam⁰The phase shifting ring lens is referred to as a first type of SDL (SDL-I) microscope. In SDL-I, by using 180⁰Phase shift lens to realize 180⁰Phase shifting is difficult to manufacture. The second proposed type of SDL (SDL-II) microscope employs two 180⁰The phase-shifted laser cross beams pass through an airy disc lens and a same-phase ring lens, respectively, to obtain an airy disc beam and a reverse amplitude ring beam to form depleted nanobeams at beam intersections. It is clear that in the SDL-II microscope, 180 is set⁰The phase shift and lens fabrication are separated to make the lens unit less complex to fabricate. Two 180⁰The phase-shifted crossed beams may be two laser sources, or may be from the same laser source, and then one beam may pass through one 180⁰Phase shifting lens to alter laser phase 180 prior to passing through SDL-II microscope⁰. Other methods of changing the phase of the laser beam also exist.

Fig. 111100 shows a trimeric lens attached to an airy disc lens and a ring lens. As previously described, the trimerization lens cell has three sub-wavelength airy disk beam lenses (the minimum number for the annular lens cell) located at the vertices of an equilateral triangle to form an airy disk beam having a trimerization shape. FIGS. 11(a) -11(c) show the top view, airy disk beam and amplitude and intensity of the airy disk lens 1110, the ring lens 1120 and the trimerizing lens 1130, respectively. In fig. 11(a), an airy disk beam 1112 is obtained after the laser beam passes through an airy disk lens 1110 having a subwavelength hole, and 1114 is the amplitude and intensity of the airy disk beam. In fig. 11(b), after the laser beam passes through the ring beam lens 1120, a ring beam 1122 is obtained, and 1124 is the amplitude and intensity of the airy disk beam, where the intensity is composed in the shape of a hump of a dotted line. In fig. 11(c), after the laser beam passes through the trimerization lens 1130, trimerization beam 1132 is obtained and 1134 is the amplitude and intensity of the trimerization beam, where the composed intensity is in the shape of a deep hump of a dotted line. Comparing the composite intensity line 1124 from the ring beam lens 1122 to the composite intensity line 1134 from the trimerization beam lens 1132, the trimerization beam lens can produce a composite intensity having a much deeper hump shape, shown as a dotted line at 1134, which can be used to deplete the airy disc beam to obtain a sharp composite nanobeam probe. The trimeric deep peak shape also has more room to obtain a uniform fine composite nanobeam.

FIGS. 12(a) - (d) show in 1200, respectively, the top view, cross-sectional view, amplitude and intensity, and corresponding airy disk beam of a first embodiment SDL-II microscope lens unit 1210, the lens unit 1210 being formed by an annular beam lens 1120 to be smaller than and close to 180⁰Angle α of (a) is joined by an airy disk beam lens 1110; the second embodiment SDL-II microscope lens unit 1220 is made up of a trimerization beam lens 1130 and is smaller than and close to 180⁰Angle α of (a) is joined by an airy disk beam lens 1110; and the third embodiment SDL-II microscope lens unit 1230 is comprised of a trimerization beam lens 1130 of less than and approximately 180⁰Angle alpha of engagement of the compact trimerisation lens 1232. FIG. 12(b)1240 shows a cross-sectional view of the three lens units of FIG. 12(a), respectively, with two lenses in each lens unit being smaller than and approaching 180⁰Is engaged and is at (180)⁰Two 180 of 1242 and 1244 of angle- α)⁰The phase shifted cross beams pass perpendicularly through two flat lenses at each lens cell and combine into a nanobeam of 1246 at the beam intersection. In 1250 of fig. 12(c), the corresponding amplitudes and intensities of the airy disk beam 1242, the ring beam 1244 and the composite nanobeam 1246 at the intersection beam point are shown, respectively. In FIG. 12(d) two 180 are shown at 1260, 1270 and 1280 respectively⁰After the phase-shifted cross beams pass through their respective two lenses, the phase-shifted cross beams pass from lens unit 1210, lens unit 1220

andthree nanobeam

1262, 1272 and 1282 obtained by the lens unit 1230. The airy disc beam 1112 and the trimerization beam 1132 from the lens unit 1220 obtain a finer composite nanobeam 1272 than the composite nanobeam 1262 obtained from the annular beam 1122 of the airy disc beam 1112 from the lens unit 1210, as previously discussed. However, composite nanobeam 1272 may have some uncompensated shadow beams around the edge in addition to the nanobeam, and this shadow beam around the edge may cause problems in imaging and manufacturing. This shadow beam problem can be solved in a lens cell design 1230 consisting of a compact trimerization lens 1232 that produces a solid trimerization beam and a trimerization beam lens 1130 that produces a hump-shaped trimerization beam. At two 180⁰After the phase shifted cross beams pass through 1232 compact trimerization lens and 1130 normal trimerization lens, solid trimerization beams 1232 and reverse amplitude hump trimerization beams 1132 can be obtained and they will compose fine nanobeams 1282 at the cross beam points without shadow beam problems.

However, all three lens units in fig. 12 do not maximize the use of laser power because the laser spot is much larger than the size of the sub-wavelength lens. The hemispherical shell lens (or hemispherical lens) and the spherical lens shown in 1300 of fig. 13 are proposed to solve this problem by maximizing the use of laser beam power to produce a high amplitude composite nanobeam. 1310 and 1320 in fig. 13(a) show top views of the hemispherical case lens unit (or hemispherical lens unit) or the

spherical lenses

1312 and 1322, respectively. The 1312 lens unit consists of a set of airy disk lenses 1110 and a set of ring beam lenses 1120. The 1322 lens unit consists of a set of compact trimerization lenses 1324 and a set of trimerization beam lenses 1130 in order to obtain a uniform sharp composite nanobeam probe as illustrated in 1280 of figure 12. A hemispherical shell lens (or hemispherical lens) or spherical lens may focus all beams from a set of airy disk lenses in the design 1310 and a set of ring lenses or from a set of compact and a set of trimerization lenses in the design 1320 into beam intersections. 1330 and 1340 in FIG. 13(b) respectively show a lens unit with 1312A hemispherical shell lens (or 1322 lens unit) and a spherical lens with 1312 lens unit (or 1322 unit). Two 180 of 1242 and 1244 in the hemispherical shell lens of 1330 and the spherical lens of 1340⁰The phase shifted cross beam will pass through the lens unit 1312 (or 1322) and be focused at

beam crossover points

1332 and 1342 to respectively constitute the nanobeam. The hemispherical shell lens and the spherical lens will focus all beams at the beam intersection point to increase beam amplitude by fully exploiting the laser spot power.

1350 and 1360 in FIG. 13(c) are shown at two 180, respectively⁰The phase shifted cross beams pass through the corresponding airy disk at the beam crossover point 1332 (or 1342) behind the

lens cells

1312 and 1322 on the hemispherical shell lens (or spherical lens). 1350 shows the airy disc beam 1112 obtained after the laser beam 1242 passes through the set of airy disc beam lenses 1110 in the 1312 lens unit and 180⁰The reverse amplitude annular beam 1122 obtained after the laser phase-shifted beam 1244 passes through the set of annular beam lenses 1120 in the 1312 lens unit will constitute the nanobeam 1352 at 1332 and 1342 for the hemispherical shell lens 1330 and the spherical lens 1340, respectively. The composite depleted nanobeam 1352 in fig. 13(c) is similar to 1262 in fig. 12(c), but has a much higher amplitude due to the use of a set of

sub-wavelength lenses

1110 and 1120 to fully use the laser beam spot and also use focusing lenses (e.g., hemispherical shell lens, hemispherical lens, and spherical lens) to focus the airy disc beam and the annular beam at the beam intersection. 1360 shows a firm trimerization beam 1326 obtained after the laser beam 1242 passes through a set of compact trimerization beam lenses 1324 in the 1322 lens cell and 180⁰A reverse amplitude trimerization hump beam 1132 obtained after the laser phase shift beam 1244 passes through a set of trimerization beam lenses 1130 in the 1322 lens cell will constitute a high amplitude nanobeam 1362 at 1332 and 1342 for the hemispherical shell lens 1330 and the spherical lens 1340, respectively.

Fig. 14(a) and (b) show a top view 1410 and a cross-sectional view 1420, respectively, of a spherical lens (or hemispherical shell lens) on a cantilever probe in 1400. 1410 overhead view of cantilever frameTwo holes 1414 and 1416 are shown on the cantilever of 1412 for two 180⁰The phase shifted cross beams pass through. The AB line passes through the center of 1414 and the center of 1416. 1420 is a cross-sectional view through line AB showing a spherical lens cell (or hemispherical shell lens cell) attached to a probe 1421 at an angle β, which is also two 180⁰The phase shift intersects the angle of the beam. Two 180⁰The phase-shifted cross beams pass through two

hollow legs

1414 and 1416 of probe 1421 and then through hemispherical shell lens 1330 (or spherical lens 1340) to compose depleted nanobeams for nanometer-scale lithography or imaging.

A spherical lens unit (or hemispherical shell lens unit) may also be placed only on the cantilever, and this is shown at 1500 in fig. 15. Fig. 15(a) shows a cantilever top view without a spherical lens unit (or hemispherical lens unit) placed, where the cantilever 1512 has had a hole 1514 to place the spherical lens unit (or hemispherical shell lens unit) in 1510. The AB line is the crossing line through the middle of the hole 1514. FIG. 15(b)1520 shows a top view of the cantilever after placing the spherical lens unit 1320 (or hemispherical shell lens 1310) in 1514 on the cantilever 1512. Fig. 15(c) shows a corresponding cross-sectional view of 1520 through the AB line, where 1330 and 1340 are cross-sectional views of a hemispherical housing lens unit and a spherical lens unit, respectively.

N of one-dimensional 1-D or even N x N of 2-D multiple lens units can be employed to speed up the imaging or fabrication process. Fig. 16(a) and 16(b) show top views of 2 x 2 lens cells on the frame in 1610 and corresponding 2 x 2 composite depleted nanobeams on the sample surface in 1620, respectively, at 1600 for illustration. The 2 × 2 lens units may be 2 × 2 180 lens units in an SDL-I microscope, respectively⁰

Degree phase shift

812, 920, and 1010 lenses. The 2 x 2 lens units may also be 1210, 1220, 1230, 1310 and 1320 lens units, respectively, in an SDL-II microscope. The distance between two lens units along X and Y is D_xAnd D_y. Then, a 2 × 2 nanobeam of 1622 is formed at (0, 0), (0, D)_y)、(D_x0) and (D)_x，D_y) Shown as 1620 in FIG. 16 (b). The beam may be fixed while the sample stage is scanning. For an N lens matrix design, if the distance between two adjacent lenses is d along the X and Y directions, respectively, then each lens needs to handle the area of d, and then can handle (N)²×d²) And the process will be faster than a single lens unit by N². This also includes the case of N multiple laser sources, where one laser source can cover N × N lens matrices, and then the efficiency of the process can be N × (N × N) times that of a single lens cell in the single source case.

FIG. 171700 illustrates 180 using two polarizations⁰Phase shifting

intersecting beams

1712 and 1714 constitute a sharp SDL-II microscope depleted of nanobeams 1716 at the beam intersection. Two 180 at beta cross beam angle⁰Phase-shifted

polarized beams

1712 and 1714 pass through lens unit 1240 to form depleted nanobeam 1716. Obviously, both the horizontal and vertical components of the two beams will be depleted in the overlap region to leave a uniform fine composite nanobeam.

Fig. 181800 illustrates an SDL-II microscope similar to that in 1700 of fig. 17, but the airy disc beam lens 1812 and the ring beam lens 1814 are not engaged and can move independently. After the laser beam passes through the ring lens (or the trimerization lens), the ring beam (or the trimerization) will initially be a ring beam (or a hollow trimerization) and will then mix into a stable airy spot beam (or a stable trimerization) with increased working distance, and it is critical that the beam be maintained as a fine aperture ring beam (or a fine hollow trimerization) at the intersection of the intersecting beams. Independent cantilever frame movement for the annular lens (or the trimerization lens) can ensure that the annular beam (or the hollow trimerization) is obtained at the intersection of two intersecting beams by changing its working distance, with the reverse amplitude airy disk depleted to be used in an SDL-II microscope or in a microscope with two separate airy disk lenses and 180⁰The nanobeam probe is formed in an SDL-I microscope against a phase shifting ring lens. Fig. 181800 shows the case of two polarized crossed beams, but can also be applied to two normal crossed beams.

Solutions and gases may be filled between the lens unit and the substrate to further increase the image and lithographic resolution.

The above-mentioned embodiments of the SDL microscope device are illustrated merely to achieve the features and advantages of the present disclosure, are not limiting and may not be drawn to scale. This disclosure is intended to encompass any and all subsequent adaptations, combinations, or variations of various embodiments that may be utilized and derived after the present disclosure, but without departing from the spirit and scope of the present disclosure.

Claims

1. A first type of scanning depletion synthesis laser microscope (SDL-1), comprising:

a laser source;

a focusing lens;

a 180 ° phase shift lens unit comprising:

forming a 0 DEG phase-shifting Airy-patch lens on the opaque chromium (Cr) layer of the 0 DEG phase-shifting glass coating, wherein the aperture is smaller than the wavelength lambda of the laser to generate an Airy-patch beam;

forming at least three circumferentially adjacent equally spaced equally sized apertures smaller than the laser wavelength λ in the opaque chromium (Cr) layer of the 180 ° phase shift glass coating to produce a 180 ° phase shift annular beam lens;

the glass thickness of the 0-degree phase shift airy disk lens is twice or half of that of the 180-degree phase shift annular beam lens; the 0 phase-shifted airy disk lens and the 180 phase-shifted annular beam lens have the same center on the flat glass, wherein the central airy disk beam lens is surrounded by the 180 relative phase-shifted annular beam lens unit,

a support frame for the phase shift lens unit;

a detector;

a work table;

the beam is blanked.

2. The SDL-1 microscope of claim 1, wherein the light source of the laser comprises visible light, UV, EUV light, or electromagnetic waves.

3. The SDL-I microscope of claim 1, wherein the glass used to fabricate the 180 ° phase shift ring lens is coated with a thin layer of partially transmitted light on the transparent surface of the 180 ° phase shift glass to reduce the ring beam amplitude to a desired value to quench the reverse amplitude airy disk overlap from the center lens to form the nanobeam.

4. The SDL-I microscope of claim 1, wherein the phase shift unit further comprises a 0 ° phase shift airy disk lens and a 180 ° phase shift ring lens unit made on two separate flat glass lenses connected at an angle less than, and close to, 180 ° to obtain two small cross angle beams of airy disk from the 0 ° phase shift lens and ring of inverted amplitude from the 180 ° phase shift lens unit, forming depleted composite nanobeam at beam cross points.

5. The SDL-1 microscope of claim 4, wherein the phase shift unit further comprises a set of 0 ° phase-shifted airy disk lenses and a set of 180 ° phase-shifted ring beam lens units fabricated on two separate focusing lenses, respectively, the two separate focusing lenses being connected at an angle less than, close to 180 ° to form a high amplitude depleted composite nanobeam at the beam intersection.

6. The SDL-1 microscope of claim 1, wherein the 180 ° phase-shift lens unit further comprises a 180 ° phase-shifted annular beam lens unit and a plurality of 0 ° phase-shifted airy spot beam lenses on a hemispherical shell lens (or hemispherical lens), wherein the 180 ° phase-shifted annular beam lens is on a top pole and the 0 ° phase-shifted airy spot beam lenses are symmetrically distributed on a latitude circle with respect to the top pole of the hemispherical shell lens to focus all the airy spots of the 0 ° phase-shift airy spot lens and the inverse amplitude annular beams of the 180 ° phase-shifted annular beam lens unit on a beam crossing point to form depleted synthetic nanobeams,

a second scanning depletion synthesis laser microscope (SDL-II), comprising:

two beams of 180 DEG cross laser beams with relative phase shift;

a focusing lens;

an in-phase lens unit comprising:

forming an Airy-patch lens with a hole smaller than the wavelength lambda of the laser on the opaque chromium (Cr) layer of the 0-degree phase-shift glass coating;

an opaque chromium (Cr) layer of the 0 DEG phase shift glass coating is provided with at least three circumferentially adjacent equally spaced holes of the same size smaller than the laser wavelength lambda forming an annular beam lens:

a lens unit consisting of an airy disc beam lens having a plate glass and a ring beam lens, wherein the two plate glasses are joined together at an angle of less than and close to 180 DEG,

a support frame for the phase shift lens unit;

a detector;

a work table;

the beam is blanked.

7. The SDL-II microscope of claim 7, wherein the two 180 ° relative phase shifted crossed lasers comprise visible laser beams, UV beams, EUV beams or electromagnetic waves.

8. The SDL-II microscope of claim 8, wherein the laser beam further comprises two 180 ° relative phase shifted polarized beams from a visible light laser beam, a UV beam, an EUV beam, or an electromagnetic wave.

9. The SDL-II microscope of claim 7, wherein a glass surface used to fabricate the annular beam lens unit is coated with a thin layer of partial light penetration to reduce the amplitude of the 180 ° phase shifted annular beam to a value required for overlap depletion from the airy disk of the central lens to form a depleted synthetic nanobeam.

10. The SDL-II microscope of claim 7, wherein the lens unit further comprises: one set of airy lens in the dimension of the laser beam spot symmetrically arranged relative to the top pole of the hemispherical shell lens and one set of annular beam lens in the other laser beam spot.

11. The semi-spherical shell lens is used for focusing all Airy spots in the Airy spot beam lens and all annular beams of the anti-amplitude phase in the annular lens on a beam intersection point to form a depletion synthesis nanometer beam.

12. The SDL-II microscope of claim 11, wherein the lens unit further comprises a set of airy disc lenses and a set of annular beam lenses disposed polar symmetrically with respect to a top of the hemispherical lens or the ball lens.

13. The SDL-II microscope of claim 11, wherein the lens unit further comprises: a set of airy disk lenses and a set of ring beam lenses symmetrically distributed about the spherical top pole at symmetrical positions about the longitudinal circumference of the hemispherical sphere or hemispherical shell mirror.

14. The SDL-II microscope of claim 12, wherein the lens unit further comprises attaching a nano-metal tip to a bottom of the spherical lens or spherical segment lens.

15. The SDL-II microscope of claim 7 (or the SDL-I microscope of claim 4), wherein the lens unit further comprises: an independent Airy-patch lens in a first cantilever frame having its own motion control, and the annular lens unit on a second independent cantilever frame having its own motion control.

16. The SDL-I microscope of claim 1 (or the SDL-II microscope of claim 7), wherein the lens unit further consists of 1-D of N identical lens units equally spaced along the X-direction, or equally spaced along X and Y respectively along N X N identical lens units fabricated on one stage support.

17. The SDL-I microscope of claim 1 (or the SDL-II microscope of claim 7), further comprising N identical (or nearly identical) SDL-I (or SDL-II) with equal spacing of 1-D along X or N X N2-D identical SDL-I (or SDL-II) with equal spacing along X and Y, respectively, but still sharing the same platform support and the same sample stage.

18. The SDL-I microscope (or SDL-II microscope) according to claim 17, wherein each lens unit further comprises a laser beam with its own independence.

19. The SDL-I microscope (or SDL-II microscope) according to claim 18, further comprising at least one lens unit (or several lens units) with a detector for positioning in lithography.

20. The SDL-I microscope of claim 1 (or the SDL-II microscope of claim 7), wherein the sample stage is a laser interference sample stage that scans along X and Y directions, and is also movable up and down along the Z direction.

21. The SDL-I microscope of claim 1 (or the SDL-II microscope of claim 7), wherein the lens unit cantilever support frame further comprises a cantilever frame that scans in X & Y directions, and is also movable up and down in Z direction.

22. The SDL-I microscope of claim 1 (or the SDL-II microscope of claim 7), wherein the lens unit further comprises a working environment of a gas or liquid solution filled between the lens unit and the sample to further improve resolution.

23. The SDL-I microscope of claim 1 (or the SDL-II microscope of claim 7), wherein the lens unit and laser beam are stationary while the stage is scanning.

24. The SDL-I microscope of claim 1 (or the SDL-II microscope of claim 7), wherein the stage is stationary while the lens unit and the laser beam are scanned.

25. The SDL-I microscope of claim 1 (or the SDL-II microscope of claim 7), wherein the opaque glass coating is chrome, further comprising a plasma metal material of gold (Au), silver (Ag), or a metalloid material.