TWI294068B - Lithographic apparatus - Google Patents

Description

V. Description of the Invention (1) The present invention relates to a lithographic projection apparatus comprising: 1. a Koda field system for supplying a radiation projection beam; - j = f for forming a projection beam according to a desired pattern; One or two, the platen surface is used to fix a substrate; and the _ 2 projection system is used to image the pattern beam to the view coordinate portion of the substrate 2 into the knowledge and benefit device " A pattern section: i! The device of the light t is equivalent - can be generated on the substrate coordinate t, the figure wood, the term light valve " can also be used for this content. General and functional; Figure: Γ equivalent to a special type generated in the visual coordinate part of the device; integrated circuit or other device (as shown below). This effect: fixing the reticle top of a reticle. The concept of reticle is well known for lithography. 2 = reticle type including double body, interlaced phase shift and attenuation ^ bit shift, and various hybrid reticle types. According to the picture on the reticle::: The reticle is placed on the radiation beam, which can cause an impact to the reticle. Ϊ Selective transmission (when the hood is in the condition of the hood) and reflection (in the case of the hood) ). The reticle stage ensures that the reticle can be fixed in the input ray "in-beam-desired position" while ensuring that it can be moved relative to the beam and two stylized mirrors as needed. The I----------- The matrix address table of the layer and a reflective surface. The basic principle of the power of the device is (such as) the address area of the reflective surface or the reflected incident is diffracted first, and the non-address area reflects the incident. Light is non-diffractive light. Borrowed 1294068

By using a suitable 遽 ^ 嗯 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤 尤The matrix address of the demand can be implemented by the winter 1 electronic device. More information on this kind of mirror arrangement can be found in the patents of the 5th, 296, 8 9 1 and 5, 523, 1 93 national patents. </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> <RTIgt; For the sake of simplicity, the remainder of this document may in particular direct its body to the example involving the reticle stage and the reticle; however, the general principles discussed in this case can be seen above. The generalized content of the molding apparatus for the sake of simplicity, the projection system can be regarded as a &quot;lens&quot; thereafter, and the term should be broadly interpreted to cover various types of projection systems such as refractive optical lenses, reflective optical lenses. And secondary refractive optical systems. The radiation system may also include elements that operate in accordance with any of these design types to direct, shape, or control the radiation projection beam, and the elements may also be collectively or individually referred to hereinafter as &quot;lenses&quot;. In addition, the lithographic apparatus can be of the form having two or more floor mesas (and/or two or more reticle = faces). In such a 'multi-level&quot; device, additional countertops may be used side by side, or preparatory steps may be performed on one or more decks&apos; and one or more other decks are used for exposure. U.S. Patent No. 5,969,44, and U.S. Patent Application Serial No. 9/18, filed on Feb. 27, 1987, filed on Dec. No. 11 (Application No. WO 98/4079 No. 1) Lithography

1294068 V. INSTRUCTIONS (3) Devices, all of which are incorporated herein by reference. The lithographic projection apparatus can be used, for example, to make an integrated circuit (丨Cs). In this case, the molding apparatus can generate a circuit pattern corresponding to the individual layers of the 丨c, and the pattern can be imaged on a bottom plate (the 视 wafer), and the image coordinate portion j includes one or more small pieces). Has been coated with a layer of photosensitive material, resistant material). In general, a single wafer will contain an entire network of neighboring sinus coordinates, which are continuously illuminated one by one through the projection system. In the pre-device, the use of a reticle on the reticle surface allows for differences to be made in J different types of machines. In one type of lithography, each of the view coordinates is illuminated by exposing the entire reticle pattern to the squat position; the device is generally referred to as a wafer walk. Part Ϊ : f centered &quot; 'Generally known as a one-stage scanning device - per-view coordinate known reference direction (&quot;scan&quot; direction) under the projected beam pattern and simultaneously parallel or anti-parallel in this direction Scanning the substrate 一 (a light). Generally speaking, the projection system will have an amplification factor, so the rate V of the substrate mesa will be scanned, and the factor Μ I will be scanned from the substrate surface. ♦ 1 . The rate of fineness V. The lithographic apparatus described herein will be described in, for example, U.S. Patent No. 6,046,792, the disclosure of which is incorporated herein by reference. The last point of the previous point is fixed. The manuscript u heart ~ like to be exposed to the day 0 on a special agency, with the agency i &gt; or a number of calibration rods such as a small pattern processing steps continue to warm and the device In the middle of the night, the surface layer consists of the first layer of the robbery piled up. Before each exposure, the father can be ordered to reduce any positioning error between the new exposure and the past exposure.

Page 6 1294068 V. Description of the invention (4) This error is called the upper pressure error. However, some intermediate processing steps are characterized by rapid thermal annealing, thick layer deposition and deep trench calibration. This can cause up-pressure In some technologies, such as MEMS, the device can be self-benched with a problem that exposes it to an image that can be exposed. Basically, you need a degree. An object of the present invention is to gradually reduce at least one of the other objects and the other objects according to the present invention, and to characterize the feature points in the first item of the range. Preferably, the calibration mark image configuration allows a common calibration system to be used on the substrate, preferably on the front side of the substrate and on the upper side of the back side, relative to the image on the other side. According to another aspect of the invention, the steps are as follows: - providing at least a portion of the radiation to provide a spoke using the radiation system - using the molding device to impart a projection - projection of the shaped radiation beam to the radiation such as chemical mechanical polishing (CMP), etching Can damage or distort the error on the substrate. Both the Earthwork Technology (MST) and the Microelectronics Department are produced on both sides. The above-mentioned problem of precisely aligning the calibration portion of 5 micron or better on the other side of the substrate is performed on the side of the substrate. The invention is disclosed in a first section on the plane to be inserted at the end of the application on the plane of the first side of the substrate, which is calibrated on both sides of the board. Calibrating the object image of the calibration system to make a method for manufacturing a device with an exposure accuracy of 〇·5 μm or better, comprising a substrate covered by the following inductive material; projecting a beam of light; a pattern of the beam on its profile; a view coordinate area of the layer of inductive material;

V. INSTRUCTIONS (5) Each feature within the scope of the patent pending insertion is characterized by the characteristic part of the final method. In the fabrication of a lithographic projection apparatus in accordance with the present invention, a picture (such as in a reticle) is imaged onto a substrate that is at least partially covered by a material (impedance).成像This imaging ^曰: Inductive material η 丁底 j,, impedance coating and various steps of medium temperature baking. After exposure, the substrate can be forked, such as post-exposure baking (ρΕβ), rinsing, high, and mouth.

Peter van Zant, published by McGraw Hill, Public Micro-wafer Fabrication: A Guide to Semiconductor Processing Implementation, ISBN 0-07-067250-4, which is included in this paper. Other steps for the measurement/inspection of baked and imaged objects. Sequence: Step: is basically used to form an individual layer such as an IC device. The pattern may be subjected to etching, ion implantation (seepage), metal spraying, chemical action, chemical-mechanical polishing. The various steps 'both of which wish to polish a different layer. When several levels are required, then the entire step, or the variation in the basin, will have to be repeated for each new layer. Finally, a sequence of patterns will be presented on the substrate (crystal Circles. These patterns are then separated from each other by a technique such as slicing or sawing, so that individual patterns can be mounted on a carrier, connecting pins, etc. Further information on such a process can be issued, for example, by 1974. Obtained in the third edition, although the apparatus according to the present invention may be specifically referred to in the fabrication of Ic herein, it is to be clearly understood that the apparatus may have many other possible applications. For example, it can be used to make monolithic optical systems, guided and detected patterns for magnetic zone memory, liquid crystal display panels, thin film magnetic heads, etc. Technicians will be aware of the use of this variant in any of the applications. The term, light 1294068 V. Description of invention (6) Net, &quot;wafer" or ''small piece') should be replaced by the more general term "mask", "substrate," and "visual coordinate area" In this document, the terms illuminating radiation and illumination beam are used to cover all types of electromagnetic radiation 'including ultraviolet radiation (such as having a wavelength of 36 5, 248, 193, 157 or 126 nm) and EUV (ultraviolet), and A particle beam such as an ion beam or an electron beam. The present invention will now be described by way of example only with reference to the accompanying drawings in which: FIG. 1 depicts a lithographic projection apparatus according to an example of the invention; BRIEF DESCRIPTION OF THE DRAWINGS A schematic cross-sectional view of a wafer table with a two-branch optical system for dual side calibration; FIG. 3 is a plan view of a wafer in accordance with an embodiment of the present invention, Position and method of calibrating the lens on the surface; side view 4 is a modification position and method of the plan view according to the present invention; only + lens Fig. 5 is a cross-sectional view of the face of the integral optical member of the partial wafer a π, having BRIEF DESCRIPTION OF THE DRAWINGS FIG. 6 is a schematic cross-sectional view of a wafer stage showing an optical system for a dual-side $p^_column surface according to another example of the present invention; and FIG. 7 and FIG. No. 2 reticle marks, calibrates two 曰曰曰 round marks in the calibrated mirror pattern, etc. The reference symbols indicate equivalent parts. Example 1 Figure 1 summarizes one according to: lithographic projection like a specific example of the present invention Device. this

Page 9 1294068 V. INSTRUCTIONS (7) The device comprises: a radiation system LA, Ex, IL for supplying a light beam (such as ultraviolet radiation) to the projection beam Ρβ; • a configuration of a reticle holder An object table (mask table) ΜΤ for fixing a reticle (such as an optical net), and simultaneously connecting the first positioning device for accurately positioning the reticle relative to the object PL; arranging the second object table of the substrate holder a (substrate mesa) WT for fixing a substrate W (such as an impedance coating wafer) while connecting a positioning device for accurately positioning the substrate relative to the object PL; • a projection system ("lens") PL (such as A quartz lens system) for imaging the illuminating portion of a reticle MA is located at a viewing frame of a substrate w having one or more small pieces).匕 As described herein, the device is a transmission type (i.e., has a transmission mask). In general, however, it may be, for example, a reflective type (with a cover). Alternatively, the device can use another type of forming device, = the stylized mirror arrangement of the above discussion. The radiation system includes a source LA (such as an ultraviolet laser) that produces a radiation beam. This beam is directly or through an input-lighting system (illuminator) (10) such as a walk and a second Ex. Illuminator steam == device AM, used to set the outer range of the intensity distribution within the beam (the % of the ship and the side of the knife and/or the inner radial target of the knife) (the knives are σ - outer and σ - Inside). This contains a variety of other components, such as an integrator ΙΝ (3) will: This, the light on the glare of the impact ray, in its profile: two-neck two-in-one and intensity distribution.

Page 10 1294068 V. Description of the invention (8) "1 It is advisable to understand the light source so that it can be placed in the frame of the lithographic projection farm (for example, when it is like - Mercury m brother), but it can also be far away from ^ 2:; The generated radiation beam is introduced into the device (such as borrowing + = mirror surface); thereafter - the phenomenon f is the condition when the light is a laser field. The invention and the patent application scope also include these phenomena. Then, the light fixed in the mask holder on the mask top MT is cut off. After passing through the mask MA, the light beam PB passes through the lens pL, and the photon is "," on the visual coordinate portion C of the substrate W. With the aid of the positioning device (and the dry selection f measuring device IF), the substrate table WT can be accurately moved to position the different visual coordinate portions c within the PB path. Similarly, the first device can be used to accurately position light = MA relative to the path of the beam PB after mechanical removal from a mask group, such as reticle MA, or during a scan. In general, the movement of the object table tops MT, WT will be cut by a long % component (coarse positioning) and a short stroke component (fine positioning), which are not explicitly shown in FIG. However, in the case of a wafer stager (as opposed to a phase scanning device), the reticle surface can be connected to a short-stroke actuator and the second is fixed. /疋 The above devices can be used in two different modes:

h In the stage mode, the reticle stage MT remains substantially stationary, and the entire reticle image is projected to a coordinate portion C in one pass (such as a single "flash"). Then, the substrate mesa WT is moved in the X and / or y directions so that the different visual coordinate portion C can be illuminated by the light beam PB); 2 in the scan mode, basically the same basis, the difference is - The known coordinate portion C is not exposed in a single "flash". Conversely, light

Page 11 1294068

The cover table MT is moved at a speed-in-known direction (so-called "scan direction", so that the projection beam PB is used to sweep over the reticle image; at Ϊ I! The mesa WT moves simultaneously in the same or opposite direction at a rate V = MV, where Μ is the magnification of the lens PL (substantially M = 1/4 or 1/5). In this way, a larger visual coordinate portion c can be exposed without having to sacrifice the solution degree.

Figure 2 shows wafers w on a wafer deck WT. The wafer mark and WM4 are disposed on the top surface of the wafer W, and the light can be reflected from the marks shown by the front of the WM3 and WM4, together with an alignment system (not shown) which will be described later. Used to calibrate the logo on the reticle. The other wafer marks WM1 and WM2 are disposed on the back side of the wafer W. An optical system is implanted in the wafer table WT to provide optical access to wafer marks WM1, WM2 on the back side of the wafer w. The optical system includes a pair of arms 1 〇 A, 1 〇 B. The female arm comprises two mirrors 12, 14 and two lenses 16, 18. The mirrors 1 2, 14 in each arm are inclined such that the sum of the angles with the horizontal is 90 degrees. Thus, the end of one of the vertical impact mirrors will still be vertical when reflected from the other mirror.

In use, light is directed from above the wafer mesa MT to the mirror surface 12, through the lenses 16 and 18, to the mirror surface, and then to the individual wafer marks WM1, WM2. Light is reflected off a portion of the wafer mark while returning along the optical system arm via mirror 14, lens 16 and 18, and mirror 12. The mirrors 1, 2, and 4 and the lenses 16 and 18 are arranged such that a wafer is marked with WM 1 and WM2 images 2〇A, 20B and formed on the plane of the front (top) surface of the wafer w, which corresponds to any The vertical position of the wafer marks WM3, WM4 disposed on the front side of the wafer W

1294068 V. Description of invention (10). The images 20A, 20B of a wafer mark WM1, WM2 act like a virtual wafer mark, which can be substantially the same as the real wafer mark disposed on the front (top) side of the wafer W by the pre-stored calibration system (not shown) 'Used for school and standard. As shown in Figure 2, the arms of optical systems 10A, 10B produce images 20A, 20B that are displaced to the side of wafer W so that they can be seen by a calibration system above wafer w. Figures 3 and 4 show two of the optical system i〇A, 10B arms = good orientation, which is a plan view of the wafer placed in the XY plane. The crystal is concise and omitted from Figures 3 and 4. In Fig. 3, the arms of the optical system 1A, 〆 10B are aligned along the X axis. In Fig. 4, the arms of the optical system 1 〇Α, 1 〇 β are parallel to the γ axis. In both cases, the wafer marks WM1, WM2 sit on the X-axis. Wafer marks WM1, WM2 are placed on the bottom side of the wafer W, which is inverted from the top side of the wafer W. However, the arrangement of the lenses on the arms of the optical system means that the images of the wafer marks WM1 and WM2 are restored to the correct mode instead of being inverted, so that the images 20 A, 2 0 B are exactly the same as they are placed on the wafer. The top side of w. The optical system is also arranged such that the wafer mark, the volume ratio of WM2 to its image is 1:1, that is, there is no enlargement or reduction. Therefore, the images 20A, 20B can be used as if they were real wafer marks on the front side of the wafer w. A general calibration pattern or chain that is placed on the reticle can be used to perform calibration with true and false wafer standards. In the case of the consumables, the wafer marks are simultaneously disposed at the corresponding positions on the front and back sides of the wafer w as shown in FIG. In Figures 3 and 4, only the wafer marks on the back side of the wafer W are shown for the sake of brevity. According to this combination, when the wafer is defective? By 1294068

When the 3% or gamma car is rotated and rotated, the wafer mark on the top side of the wafer W will be located on the bottom side, and its position is suitable for imaging by one arm of the optical system 10A, 10B. . It is also understood that due to the mirror arrangement, the displacement of the wafer in the direction of the parallel optical system arm 1〇W〇B will shift the wafer mark WM1 and the dragon 2 in the opposite direction on the bottom side of the wafer. The image is 20Α, 20Β. For example, in Figure 3, if the wafer W is shifted to the right, the images 2〇Α, 2〇Β will be shifted to the left. The software that controls the %c barebone system considers when to determine the position of the wafer mark i, WM2, and when to adjust the position of the wafer boundary and the reticle when performing calibration. If the two arms of the optical system 1 〇A, 10 0B are symmetrical, then when the wafer is displaced, the separation between the images 20A and 2〇B will in fact remain at least two sides of the wafer W side. Wafer logo. A single mark can be provided!! The relative position of the image on a specific point on the wafer at a specific point on the mask. However, to ensure proper orientation calibration and amplification, at least two markers are used.

Figure 5 shows a cross-sectional view of a partial wafer table WT. According to this embodiment of the invention, the optical system 丨〇A, 10B for imaging the wafer mark on the back side of a wafer is implanted in the wafer table. As shown in Fig. 5, the mirror faces 1 2, 14 of the optical system arm are not configured as a separate member, which is integrally formed with the wafer table WT. A suitable front side is machined into the wafer table WT, which in turn can be configured with a coating to improve reflection and form mirrors 丨2, 丨4. The optical system is made of a material such as zer〇dUre that is identical to the wafer deck. Direct thermal insulation has a very low coefficient of thermal expansion, thus ensuring high calibration accuracy.

1294068 V. INSTRUCTIONS (12) EXAMPLE 2 Figure 6 is a diagram corresponding to Figure 2, but using individual fibers 3 〇 (or bundles of fibers attached to each other) and lenses 32, 34 to form an arm of the optical system 1 0 A, 1 〇B, 俾 Connect light into and out of fiber 30. The fiber and lens are used to provide an image 20A, 20B of wafer marks WM1, WM2 on the back side of the wafer W. The image 2 0 A, 2 0 B is placed on the same plane as the wafer front side W Μ 3, W Μ 4 on the front side of the wafer W. Figures 7 and 8 show another aspect of the calibration system. In Fig. 7, a radiation source such as a laser light of HeNe laser light guides a calibration beam to a first beam splitter B S1, so that part of the light is directed downward into the wafer table | The arm 1a of the system is reflected off the first wafer mark WM1 on the back side of the wafer w, and forms an image 2〇A of the calibration mark. The light from the image 20A passes backward through the first beam splitter BS1, through a lens system PL, and then through a first mask·mark MM1 disposed on a mask to the first detector. The signal generated by the detector D1 can be used to determine the correct calibration between the first mask mark MM1 and the image 2 〇A. The relationship between the image ~ 20A and the wafer mark WM1 can be obtained from the optical member 1A, because this can determine the calibration between the first mask mark MM1 and the first wafer mark WM1. Wafer W and/or reticle MA can be moved relative to complete calibration. The calibration system of this target example is a through-lens (TTL) combination, so that the lens system PL between the cover MA and the wafer W is actually a projection lens for exposure light exposure. However, the calibration system is off-axis (〇A). In Figure 8, a second wafer labeled WM2 uses a second crying BS2 and other optical system arms 1 〇 β and - second reticle standard '

Ϊ 294068 V. INSTRUCTIONS (13) This process can be repeatedly calibrated, such as the first reticle mark MM1 and the second crystal TT, WM2, and the like. Calibration can also be performed on wafers on the front (top) side of the wafer. • Only shown with the same or other mask marks. The image of the object on the side is relative to the position of the first wafer mark, and the following is an example of a double side calibration method. The first wafer mark is disposed on a first side of a wafer. One or more exposures are performed using the first wafer mark on the side, and 俾 is calibrated in the usual manner. Therefore, the complete establishment of the round first / day 丨Ϊ Λ 从 / from · τβ &quot; factory π Yang four you in &lt; j dan. Wafer your continent, so that the first side is facing down, and the exposure can be performed on the second side = use the optical surface of the wafer table, the first wafer is imaged, the same:, on the mask The key is located on the first side of the wafer (the position and orientation of the object image relative to the reticle is now established. Then, the second 曰曰 mark can be on the wafer (currently on the top side) Exposure on the second side (provided) ° second wafer standard relative to the first crystal

Black: Γ: = Γ position, can be determined by the reticle standard and calibration system, object exposure can use the second wafer mark correction measures and the second gamma in the wafer — #你★, oyster I must be on the first side of the wafer.士:= ,? It accurately corrects the relative relationship between the yen marks of the previous day, and exposes the object to the side of the image, while ensuring that the device is image-only on the opposite side of the wafer, but only in the The wafer is used for all exposed light. It is not necessary to know that the back side is formed on the back side of one side of the wafer. The wafer mark cover can be used. When the back side wafer wafer mark can be used and the front side is exposed, the same can be used. ^ The right to use. The far image calibration is shown on the front side. Absoluteness between the objects of light

1294068 V. INSTRUCTIONS (14) Relationships, as long as all of the reticle used for exposure on the front side are consistently aligned by using the image of the backside wafer. Since the processing is done on the front side of the wafer, the wafer mark on the back side will not degrade. While particular examples of the invention have been described above, it will be appreciated that the invention may be practiced differently than the foregoing. The above description is not intended to limit the invention.

Page 17 1294068 Schematic description

Page 18

Claims (1)

1294068 96. 11.23 Patent Application No. 90103127 96.11 Chinese Patent Application Substitute (November, 1996) 1. A lithographic projection apparatus comprising: - a radiation system for providing a radiation projection light - a sizing device for shaping a projection beam according to a desired pattern; a substrate table for fixing a substrate; a projection system for imaging the shaped wire with (7) to a view coordinate portion on the first side of the substrate, the feature further comprising: a calibration system for calibrating on the substrate a flag that aligns with a pattern of a certain type of device; and an optical system for providing an image of the calibration mark for use by the calibration system, wherein the calibration target minus the first side is placed on the opposite side of the substrate, and wherein the warhead system Calibration is performed using a calibration marker disposed on the first side of the substrate and using the calibration marker image provided by the light (4). 2. The device of claim 1, wherein the optical system is arranged to provide an image of the calibration mark on a plane on a first side of the substrate. 3. Apparatus according to claim 1 or 2, wherein the optical system comprises means for providing a plurality of images, each of which corresponds to a plurality of individual calibration standards. 4. According to the cap-specific or two-piece device, the light (4) includes at least two mirrors and lenses. 5. The device according to the first or second aspect of the invention, wherein the wire system comprises at least one light. The device according to the application of the first item, wherein the optical system is integrally formed with the wire table. 69255-961123 画 [[line.doc/llm 1294068 装置 装置 申 申 专利 , , , , , , , , , , , , , , , 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学 光学From the corresponding calibration mark, it is removed from the periphery of the area occupied by the secret board. According to the apparatus of the patent application, the calibration system provided by the optical system is the same size as the calibration standard provided on the _ side of the substrate. 9. Apparatus according to the ninth aspect of the patent application, comprising an invertor for inverting the substrate such that the first side is interchangeable with the opposite side. 10. According to the scope of the patent application! Or two devices, and a device for simultaneously exchanging a relationship between the two sides of the substrate at the same time. 11· According to the scope of application materials! Or the device of claim 2, wherein the sizing device comprises a reticle surface for fixing a reticle. 12. The device of claim 11, wherein the pattern of the sizing device for calibration is a calibration mark disposed on the reticle. 13. A method of fabricating a semiconductor device comprising the steps of: - providing a substrate at least partially covered by a layer of radiation-sensitive material; - providing a radiation projection beam using a radiation system; - imparting a profiled pattern to the projection beam using a sizing device - projecting the shaped beam of radiation to the apparent coordinate area of the layer of radiation-sensitive material on the first side of the substrate, characterized by the following steps: providing a calibration system for calibrating the sizing device with a calibration mark disposed on the substrate a pattern; an optical system is provided to form an image of the calibration mark for the calibration system to line 69255-961123. doc/llm -2-!294〇68 with '%c of the standard to the _ side Aligning the opposite side of the secret panel; calibrating the image of the calibration mark with the pattern of the 装置-type device: and calibrating a calibration mark placed on the first side of the substrate in a pattern of a 疋 疋-type garment, wherein Both calibration steps are performed using this calibration (4). 4. The method according to item 13 of the π patent scope, further comprising the steps of: forming a calibration target image on a plane on the first side of the substrate. I5· According to the method of the special conversion item, the calibration image of the t-pitch optical purity is the same size as the scale provided on the base side. 16. The method of applying the _13 or _, the method comprising the steps of: inverting the substrate such that the first side is interchanged with the opposite side; and repeating the calibration. Π· According to the method of the patent application No. 3, the additional steps are as follows: At the same time, a relationship is derived between the calibration targets on both sides of the to. 69255-961123 Dash.d〇c/llm