JPH04148812A - Position detecting apparatus - Google Patents

Abstract

PURPOSE:To detect the amount of the relative position between a first object and a second object in high accuracy by adequately setting the arrangement of alignment marks which are provided on the surfaces of two objects. CONSTITUTION:Two alignment marks 5 and 6 are arranged along the detecting direction of position deviation on the surface of a first object 1. Two alignment marks 3 and 4 on the surface of a second object are arranged in the regions which are separated from the regions of the surface of the second object 2 on which two marks 5 and 6 on the surface of the first object 1 are projected by the specified amounts in the direction perpendicular to the position-deviation detecting direction. Luminous fluxes 7 and 8 are cast onto the marks 5 and 6 at specified angles and then transmitted and diffracted. The luminous fluxes are further reflected and diffracted at the marks 3 and 4 and cast onto detecting parts 11 and 12. Then, the positions of the centers of gravity of the luminous fluxes 7 and 8 which are cast on the surfaces of the detecting parts 11 and 12 are detected. The output signals from the detecting parts 11 and 12 are utilized, and the position deviation is detected.

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a position detection device, and is used, for example, in an exposure device for manufacturing a conductive element r, such as a mask or a reticle (hereinafter referred to as "r").
It's called Mask J. ) When a fine electronic circuit pattern formed on a first object 1 such as a wafer is transferred by exposure to a second object 2 such as a wafer, the relative positional deviation 1d between the mask and the wafer is determined and stomach! The present invention relates to a position detection device suitable for performing positioning (alignment). (Prior Art) Conventionally, in exposure apparatuses for manufacturing F conductor elements, relative alignment between a mask and a wafer has been an important element for improving performance. In particular, with regard to alignment in recent exposure apparatuses, alignment accuracy of, for example, submicron or less is required due to the integration of conductive elements. In many position sensing devices, the mask and wafer blood 1
- (, set the so-called alignment marks of the 6-point river, and are masked from them (, using the i7 location information,
Alignment 1~ is being performed on both sides. In this case, the alignment method 1 may include, for example, detecting the deviation of both alignment marks by performing image processing, or using U.S. Pat.
As proposed in 8-υ and Japanese Unexamined Patent Publication No. 56-1570: II, a zone plate is used as an alignment mark, a beam of light is irradiated onto the zone plate, and at this time, the beam emitted from the zone plate is placed on a predetermined surface. This is done by detecting the focal point (i'7 position, etc.).Generally, alignment method using zone play 1~
Compared to methods using immediate alignment marks, this method has the advantage of being able to achieve relatively high-grain alignment without being affected by alignment mark defects. FIG. 6 is a schematic diagram of a conventional position detection device using Zone Play 1. In the figure, a mask M is attached to a membrane 117, and is attached to a mask chuck 1 on an aligner body 115.
16. An alignment head 114 is arranged above the main body 115. 1. Aligning the mask M and wafer W. In b, a mask alignment mark MM and a wafer alignment mark WM are printed on the mask M and the wafer W, respectively. The light beam emitted from the light source 110 is converted into seven lines by the projection lens system 111, passes through the half mirror 112, and enters the mask alignment mark MM. The mask alignment mark MM is composed of a transmission type zone plate, and the incident light beam is diffracted, and the +1st-order diffracted light is subjected to a convex lens action to be condensed onto a point Q. Further, the wafer alignment mark WM has a convex mirror function (divergent function) that reflects and diffracts the light condensed to the convergence point Q by the reflective zone plate and forms an image on the pre-detection point 1]91-. At this time, the signal light flux that has undergone the first-order reflection and diffraction effect at the wafer alignment mark WM is reflected at the mask alignment mark M.
When passing through M, it is transmitted as zero-order light without being subjected to lens action, and is focused at 119-, I= before detection. Here, the alignment mark MM of the mask M receives an n-order diffraction effect, and the alignment mark WM of the wafer W receives an n-th order diffraction effect.
Hereinafter, for convenience, the light beam that is subjected to the next reflection diffraction effect and then subjected to the first-order diffraction effect again at the alignment mark MM of the mask M will be referred to as (m, n, fl,)-order light. Therefore, the above-mentioned light flux becomes a signal light flux of (1, -1°0) order light.6 In the 417-position detection device shown in the figure, if the wafer W is misaligned by a predetermined amount relative to the mask M, That(+
'/misalignment' ΔOW, the light flux irradiated by the person at 1191 before detection, Q, I (1'7 position (1 of light Di)

[Heart position] is shifting. At this time, the deviation of the detection surface 1190 ii (Δ
There is a constant relationship between δW and positional deviation ΔσW, and by detecting the maximum deviation ΔδW of the detection surface 1190 at this time, the maximum relative positional deviation ΔOW between the mask M and the wafer W is detected. As shown in the figure, when the distance from the condensing position Q of the signal beam emitted from the mask M to the wafer 2 is aW, and the distance from the wafer W to the detection surface 119 is bW, the detection surface 1191-
The positional deviation amount ΔδW is as follows. As is clear from equation (a), the amount of positional deviation is expanded by a factor of (b w / a wl). This (bw/a w-1) is the positional deviation detection magnification. In addition, in the apparatus shown in the same figure, the incident position (reference position) of the signal light beam when there is no positional deviation of 1 jl-1 between the mask and the wafer is generally used as a reference after a test firing etc. is performed after the mask M is fixed, and this position and the actual light flux are Deviation from the incident position of radiation: detection surface 1
19, and using the value ΔδW at this time, I′ device deviation Jl; Δ0 is determined from equation (a). (Problems to be Solved by the Invention) Generally, in the 4☆ position detection device shown in FIG. 6, the detection surface 1190 has holes of diffraction orders (0.
-1.1) There are cases where the secondary light is almost condensed. For example, after being incident on the alignment mark MM on the mask M, this is transmitted as the 0th order diffracted light, and the wafer W1. At the alignment mark WM of the mask, it is first reflected and diffracted in the 1st order and is affected by concave power (divergence), and then at the alignment mark MM of the mask Ml-'', it is transmitted and diffracted in the -1st order, resulting in convex power (
The (0.-1.1) order light that has been affected by
In some cases, the light is almost focused on 19. Figure 7 shows the (1, -1, O) order light and (0, -1
, 1) is an explanatory diagram schematically showing the propagation mode r- of the next light. Here, in general, (1, -1, 0) order light and (0°1.1)
The detection magnification of the amount of movement of the incident position with respect to the relative positional deviation between the mask and the wafer] 11 is different between the second and second brother. For this reason, within the detection surface 1]9 as an incident device for the luminous flux, when the position vector from each point on the detection surface multiplied by the light intensity at that point is integrated over the entire detection surface, the integral value is When detecting the point (center of gravity of the luminous flux and 1111) that becomes a 0 vector, in addition to the (1, -1, O) order light as the signal light flux, the (0, -1,, 1) second order light is detected. ! I received 2v,
Alternatively, there were cases in which misaligned stars could not be detected correctly even if equation (a) was used due to the deterioration of the S/N ratio. If the light intensity ratio relationship between the (1, -1, O) order light and the (0, -1,1) order light is always kept constant to some extent, the light formed by these two light beams on the detection surface There is also a method of determining a detection magnification of the amount of deviation of the center of gravity position due to the entire intensity distribution with respect to the amount of relative positional deviation ΔσW between the mask and the wafer, and detecting the positional deviation using this as a new 4Q positional deviation detection magnification. In this case, the light intensity ratio of each light beam, wafer process factors such as variations in resist film thickness, or variations in the position between the alignment objects in the direction perpendicular to the positional deviation detection direction, if any, will change. As a result, the problem is that the 1-tal positional deviation detection magnification of the (1, -1, O)-order light and the (0, -1°1)-order light changes, resulting in a positional deviation detection error. there were. The present invention targets such a luminous flux (m
, n, Q)-order light becomes a detection error factor (m', n
',,M') order light, (I-j l,,m ≠m or n
'≠n or ℃'≠℃) 11-shi,
1.1 Objective: To provide a position detection device that detects "J fit" (positional deviations that occur frequently). (Means for solving the problem) The position detection device of the present invention provides a 1 object and 2nd
When detecting a relative positional deviation with an object, an alignment mark AI that performs a wavefront conversion action is provided on the first object surface, and an alignment mark B1 that performs a wavefront conversion action is provided on the second object surface. The alignment mark A1 on the object plane is provided in a predetermined end area in a direction substantially perpendicular to the positional deviation detection direction from the area projected onto the second object plane, and the light beam from the light projecting means is placed on the first object plane. incident from an oblique direction
A light beam subjected to a wavefront conversion effect by the alignment mark A1 on the object surface and the alignment mark B1 on the second object surface is guided onto a predetermined surface, and the incident position of the light beam at the predetermined 1rii t- is detected in one step. It is characterized in that the positional deviation is detected using the output signal from the detection means. Further, in the present invention, when detecting a relative positional shift between a first object and a second object that are arranged opposite to each other, two alignment marks A1. A2 is provided along the positional deviation detection direction, and two alignment marks that perform a wavefront conversion action are provided on the second object surface. The alignment mark A1 on the first object surface is provided along the positional deviation detection direction in an area a predetermined distance away from the area projected on the first object surface in a direction substantially orthogonal to the positional deviation detection direction. a first beam of light each subjected to a wavefront conversion action at the alignment mark B1 of the second object;
The alignment mark A2 of the first object surface and the second light beam subjected to the wavefront conversion action by the alignment mark B2 of the second object surface are respectively guided onto a predetermined surface, and the alignment mark B2 of the second object surface is guided onto a predetermined surface. The present invention is characterized in that the incident positions of the first light beam and the second light beam are detected by respective detection means, and positional deviations are detected using output signals from the detection means. In the present invention, the alignment marks A1, A2
．． B1. It is noted that B2 consists of a physical optical element Y- which has an imaging effect of 4+ only in the direction of the positional deviation detection force.
, 'j'. For example, in the present invention, when object plane A and object plane B are a first object and a second object that should not be aligned, the object plane A is provided with first and second signal signals that function as physical optical elements. A first lens that forms alignment marks A1 and A2 and also functions as a physical optical element on the object plane B.
And alignment marks 81 and B2 for the second signal are formed. At this time, two alignment marks B1 on the second object plane
．． , B2 are arranged by two alignment marks A1., B2 on the first object plane. A2 is a region that is a predetermined distance away from the region projected onto the second object in a direction substantially perpendicular to the positional deviation detection direction, and is provided in this region along the positional deviation detection direction. Then, a beam of light is made incident on the alignment mark A1,
The diffracted light generated at this time is made incident on the alignment mark B1, and the center of gravity of the light beam within the incident plane of the diffracted light from the alignment mark B1 is detected by the first detection section as the incident position of the first signal light beam. Here, the center of gravity of the light flux is the point in the light receiving area where the integral value becomes 0 vector when the position vector of each point in the receiving light is multiplied by the light intensity of that point over the entire surface of the receiving surface. For convenience 1, a point at which the light intensity is at its peak may be used as the center of gravity of the light flux. Similarly, when the light beam is made incident on the alignment mark A2, the resulting rotation J7
? The light is incident on the alignment mark B2, and the center of gravity of the light beam on the incident surface of the diffracted light from the alignment mark B2 is detected by the second detection unit as the incident position of the second A and τ5 light beams.Then, the first and second detection Positioning of object plane A and object plane B is performed using the two position information from the parts. At this time, (m', n', Each element is set so that the f1') order light enters the detection section and does not have an adverse effect.In addition, in the present invention, the center of gravity of the light beam entering the first detection section is
The center of gravity of the light beam incident on the device and the second detection unit is on the object plane A.
The alignment marks A1, A2 . Bl and B2 are set. (Example) Fig. 1 is a perspective view of the main part of the first embodiment of the present invention, Fig. 2 is an explanatory diagram of a part of Fig. 1 developed, and Fig. 3 is when viewed from the X direction of Fig. 1. FIG. In the figure, 1 is a first object corresponding to the object plane A, for example, a mask. A second object 2 corresponds to the object plane B, and is, for example, a wafer. The figure shows a case where a relative misalignment star between the first object 1 and the second object 2 is detected. In FIG. 1, one or two first objects are shown because the light that passes through the first object 1 and is reflected by the second object 2 passes through the first object 1 at different times. Reference numeral 5 indicates an alignment mark provided on the first object 1, and reference numeral 3 indicates an alignment mark provided on the second object 2, which are used to obtain the 1st and 6th lights. Similarly, 6 is the first object 1, and 4 is the second object 2.
This is an alignment mark provided in the 1st position, and is used to obtain the second signal light. In addition, in Figure 1, alignment mark 3
The optical path is shown in which 4 is replaced with an equivalent transmission type alignment mark. Each alignment mark 3, 4, 5, 6 is made of an optical member having a wavefront conversion function, such as a grating lens with a one-dimensional or two-dimensional lens function, or a physical optical element such as a diffraction grating without a lens function. Two alignment marks 5° 6 on the surface of the first object 1 are arranged along the positional deviation detection direction (X direction). Second
The two alignment marks 3 and 4 on the second surface of the object are moved in a direction perpendicular to the positional deviation detection force direction (X They are arranged in predetermined areas separated from each other in the direction (direction), for example, in areas that do not overlap with each other along the positional deviation detection direction. The alignment marks 3, 4, 5, and 6 all form an image in the positional deviation detection direction (X direction). For example, it is made of a grating lens having cylindrical power. It should be noted that in the X direction, it may or may not have a particular imaging effect. 9 is a wafer scribe line, 10 is a mask scribe line, and alignment marks are formed on the surfaces thereof. 7 and 8 are the first and second alignments 1 to 1 described above. A second signal beam is shown. Furthermore, 7', 8'
(not shown). The second signal beams 7 and 8 will be treated as diffracted beams of a predetermined order that will cause detection errors. In this embodiment, the first signal beam 7 is (1,-1°0)-order light,
The second signal beam 8 is (-1, 1, 0) second brother, and the beam 7' is (
The 0, -1, 1) order light beam 8' is the (o, i, -i) order light. 11. Reference numerals 12 denote first and second detection sections for detecting the first and second signal beams 7 and 8, respectively. 1st. The second detection units 11 and 12 are composed of, for example, a primary brother CD, and the arrangement direction of the elements is in the X-axis direction. The optical effects of the first signal beam 7 and the second signal beam 8 are approximately concave, and their handling is also approximately concave, so the following will mainly explain each element through which the first signal beam 7 passes. . The optical distance from the second object 2 to the first or second detection unit 11.12 will be described for convenience of explanation. The distance between the object and the second object 2 is g, the focal lengths of the alignment marks 5 and 6 are respectively f, , l+f, , 2, the relative positional deviation between the first object 1 and the second object 2 is Δσ, and The first time. Second
The displacement amounts of the first and second signal beam centers of the detection units 11 and 12 from the coincident state are respectively S and S2. Note that the alignment light beams 7 and 8 incident on the first object 1 are assumed to be plane waves for convenience, and the symbols are as shown in the figure. The displacement amount 81 and S2 of the center of gravity of the signal beam are the focal points F, , F of the alignment marks 5 and 6, and the alignment mark 3,
It is determined geometrically as the intersection of the straight line (2) connecting the centers of the optical axes 40 and 1°L2 and the light-receiving surfaces of the detection units 11 and 12. Therefore, in order to obtain the displacement amount Sl, 32 of the center of gravity of the spectral flux in the opposite directions for the relative positional deviation between the first object 1 and the second object 2, the optical imaging magnification of the alignment mark 3.4 is This is achieved by reversing the signs of . In this example, the types of light sources used are semiconductor lasers, H, -No lasers, A, lasers, and other light sources that emit coherent light beams, and light emitting diodes and other light sources that emit non-coherent light beams. . As shown in Fig. 1, for example, the actual colors are (i, -+,.) The light beam 7 as the 0th-order light and the light beam 8 as the (-i, +,, o)-order light are each mask 1. - After being incident on the alignment mark 5.6 at a predetermined angle, it is transmitted and diffracted, and then reflected and diffracted by flymen 1 to marks 3 and 4 on the 2nd surface of the wafer, and then incident on the detection unit 1.1.12. do. Also (0, -1
, 1) The luminous flux 7' as the next light and the luminous flux 8' as the (0, 1, -1) second brother pass through flymen 1 to marks 5 and 6 on the mask 1 surface in the 0th order, and then pass through the wafer 2 blood. It is reflected and diffracted by the upper alignment mark 3°4, and then transmitted and diffracted by the alignment mark 5.6 on the mask 1, and the detection part 11.12
It is incident nearby. In this embodiment, the center of gravity of the alignment light beams 7 and 8 incident on the surface of the detection section 11.12 is detected, and the center of gravity of the alignment light beams 7 and 8 incident on the surface of the detection section 1.1.
The positional deviation between the mask 1 and the wafer 2 is detected using the output signal from the wafer 12. Now, a right-handed system in which the positional deviation detection direction is the X direction, the first object normal is the Z direction, and the direction orthogonal to x and z is the X direction,
In the orthogonal coordinate system, the incident angle in the yz plane is assumed to be θ as the incident angle of the light beam as the alignment mark light onto the first object 1 surface. At this time, the arrangement of the alignment mark in the X direction perpendicular to the positional deviation detection direction (X direction) is such that the alignment mark 56 on the first object surface is transmitted through the positional deviation measurement range after pre-alignment as shown in FIG. The alignment marks 3 and 4 on the second surface of the second object are always placed first so that the zero-order light does not reach the alignment marks 3 and 4 on the second surface of the second object.
For alignment mark 5.6 on object plane 1- (ff
It is set so that the center' position deviates by a predetermined value dy in a direction perpendicular to the positional deviation detection direction, that is, in the X direction. The distance dy is a parameter to be determined based on the width of each alignment mark in the X direction and the human angle of view θ, and in this embodiment, this has been a problem in the conventional example. (11,0> order diffracted light 7 and (0,-
1,1) To suppress the simultaneous occurrence of the second-order diffracted light 7'.1. -1.
O) The distance dy is determined so that only the second light reaches the detection surface. Specifically, in Fig. 3, among the light beams that have passed through the first object 1 at the 0th order, there is one in the vicinity of the edge e on the +y side in the yz cross section of the alignment mark 3.4 on the second surface 1-1 of the second object. 111 from the condition that the light beam diffracted by the first order does not enter the area of the alignment mark 5.6 of the first object.
rli! i d, i.e., the alignment marks 5 on the first object and second object planes.
, 3 in the X direction, respectively. WyW, and alignment marks on the first object and second object plane5. :M) Set the center position in the X direction to '10. "l
o', PM the pitch (constant) in the X direction of the alignment marks on the first object and second object surfaces. When Pw is set, the position e of the edge of the -1- alignment 1~ mark is e = ! 10″+0.5Wyw, ,,, ・,
(]), and the required shedding condition is yoM-0,5WyM> c + gl, anφ ・-
-----(2). Here, φ is the exit angle in the yz plane of the −1st-order diffracted light with respect to the normal to the second object surface, and the diffraction line i′:, P, (sinθ
+sinφ) = λ...
... It can be obtained from (3). 17 (i storage) d, by definition, d y = yo'
Since 5- can be obtained by -yo' (]), the conditional expression for the distance 1IilIdy from equation (2) becomes d, > 0.5 (W, M + wy'') + gtanφ. Fan 1: Both the X direction and the X direction are C, < Δσ < e 1 (c: 1> 0
) ...(/l), the distance of the tenth period is 1d, and the distance is also d. −e, < d, < d,. + 6 (changes as = (5). Here dy
Q is the value when Δa=0, d, and O≠0. Therefore, the conditional expression that holds Aγ within the positional deviation measurement range is dy > 0.5 (WyM+Wyw) 0gjanφ+
Δσ... (2)' In this embodiment, (1, -1 , O) order light can be received by the detection unit, thereby avoiding crosstalk with the (0, -11) order light. FIG. 4(A) shows a configuration diagram of the peripheral portion of the apparatus when the first embodiment shown in FIG. 1 is applied to a proximidi type semiconductor manufacturing apparatus. As an element not shown in Figure 1, light f
A13, collimator lens system (or beam diameter conversion lens) 14, projection light beam bending mirror 15, pickup housing (alignment mark 1 housing) 16, wafer stage 17, positional deviation signal processing section 18, wafer stage drive control section 19 It is a hat. E indicates the exposure beam width. In this embodiment as well, detection of the amount of relative device deviation between the mask 1 as the first object and the wafer 2 as the second object is performed in the same manner as described in the first embodiment. In this example, the procedure for alignment is as follows:
For example, the following method can be adopted. The first method is the positional deviation between two objects] 1Δσ
The detection unit 11a of the detection unit 11.12 for the detection unit 11.12. 12b1-, the amount of deviation Δδ of the center of gravity of the luminous flux (Tj) is obtained, the signal processing unit 18 calculates the amount of positional deviation Δ0 between both objects from the center of gravity deviation signal, and calculates the amount corresponding to the positional deviation Δσ at that time. The stage drive control unit 19 controls the wafer stage 17.
move. The second method is to use the signal processing unit 18 to determine the direction in which Δ0 is canceled out by the positional deviation from the signals from the detection units 11 and 12.
The stage drive control unit 19 moves the wafer stage 1 in that direction.
7 and repeat until the position shift [Lomo Δσ] is within the allowable range. Flowcharts of the above alignment bristles 111n are shown in FIGS. 4(B) and 4(C), respectively. In this embodiment, as can be seen from FIG. 4(A), the light beam from the light source 13 is directed from the outside of the exposure light beam to the alignment mark 5.
6, the position of the incident light beam is detected by receiving the diffracted light emitted from the alignment mark 3.4 to the outside of the exposure light beam by a detection section 1.1.12 provided outside the exposure light beam. With such a configuration, it is possible to realize a system in which the pickup housing 16 does not require a retracting operation during exposure. FIG. 5 is a schematic diagram of the main parts of the second embodiment of the present invention, and FIG.
This corresponds to a cross-sectional view when viewed from the X direction in the figure. In this embodiment, only the (0, -1, 1) order light is sent to the detection unit 1 as the alignment light beam 7 for detecting positional deviation in the X direction.
j, and as the luminous flux 8 for alignment 1 ~ (0, 1, -
1) Adjust the incident angle of the light flux and the alignment marks 3, 4, 5.6 in the yz plane so that only the secondary light is detected by the detection unit 12.
are placed appropriately. Each alignment mark 3, 4, 5.6 has an imaging effect only in the X direction. In this embodiment, a light beam 7 (8) for alignment is obliquely incident on one surface of the mask at a predetermined angle in the yz plane by a light projecting means. In the figure, the a of the alignment mark 5<6) of the mask 1 is made to be incident on the non-input region. Then, the light beam that has passed through the mask 1 (transmitted in the 0th order) is transferred to the wafer 2.
Reflected and diffracted by alignment mark 3 (4) on the surface,
Next, the light beam 7 (8) diffracted by the alignment mark 5 (6) on the surface of the mask 1 is detected by the detection unit 11 (12). At this time, the light beam from the light projecting means enters the alignment mark 5 (6) on the mask 1 surface, and the light beam diffracted by the +1st order hits the area where the alignment mark 3 (4) of the wafer 2 is formed. The alignment marks 3.5 (4, 6) are arranged at an incident angle θ and within the yz plane so as not to be incident. Such conditions can be obtained by simultaneously combining the following equations using the same parameter notation as in the first embodiment. c′+ gjanζ< yo″−1T5W, W...
・(li)c'=yoM+05WyM・・・・・・・・・
(7) 1”M (sinθ 4810ζ)・＾・・
...(8) (fi), From equation (7), dy=Y when the E device deviation is 1,1 cell. The clause that should be satisfied by Yo″ is < −0,5 (W, M + W, town −) HL
anζa) 7 misalignment; 1 If the measurement range is defined by equation (4) as in the first real bM example, the condition that distance dy must satisfy within the range of equation (4) is dy<-0,5(Wy'' +−W,″)−zLanζ−
61...(9). By setting the alignment marks on each object plane 1- based on equation (11), (o, -i,
i) Next time, it is possible to detect only the tip of the pile as a positional deviation signal beam by the detection unit. In addition, in each of the above-mentioned embodiments, the center of gravity position X of the two detection units
Although there is a method of detecting the amount of change in the distance by utilizing the fact that the amount of change in the distance along the direction is proportional to the amount of relative positional deviation in the X direction between the mask and the sea urchin, the present invention is not limited to this method. For example, unlike conventional examples, the amount of deviation of the center of gravity of one detection unit from the reference position is proportional to the relative positional deviation in the X direction between the mask and the sea urchin. This method can also be applied to the same forest. (Effects of the Invention) According to the present invention, relative position detection is performed as shown below.
By appropriately setting the arrangement of alignment marks provided on two object planes, the signal light can be made symmetrical (m,
n, , Q) is a detection error factor for the second brother (m', y
+', w') It is possible to eliminate the influence of the second brother and avoid the deterioration of positional deviation detection accuracy due to crosstalk, and to detect the relative positional deviation amount between the first object and the second object with high performance. It is possible to achieve a position detecting device that can be used.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a main part of a first practical example of the present invention, FIG. 2 is a developed view of a part of FIG. Figure (A) is a schematic view of the retaining part in which the first embodiment of Figure 1 is applied to a proximity type semiconductor manufacturing equipment. Figures 4 (B) and (C) are the open side control of Figure 4 (A). FIG. 5 is a sectional view of the main part of the second embodiment of the present invention, FIG. 6 is a schematic diagram of the main part of a conventional position detection device, and FIG. 7 is a (1, -1, 0) second embodiment. and (0, -1, 1) is an explanatory diagram of the second brother. In the figure, ■ is the first object (mask), 2 is the second object (wafer), 3, 4, 5.6 are alignment marks, 7, 8
are the first. 2nd signal light beam; 9, wafer scribe line; 10, mask scribe line; 11, 12, detection section; 13, light source; 14, collimator lens system; 9 is a wafer stage drive control section.

Claims (4)

[Claims] (1) When detecting a relative positional shift between a first object and a second object that are arranged opposite to each other, an alignment mark A1 that performs a wavefront conversion effect is provided on the first object surface, and an alignment mark A1 is provided on the second object surface. An alignment mark B1 having a wavefront conversion effect is provided in an area a predetermined distance from an area where the alignment mark A1 on the first object plane is projected onto the second object plane in a direction substantially perpendicular to the positional deviation detection direction, and light is projected. The light beam from the means is incident on the first object surface from an oblique direction, and the light beam is subjected to a wavefront conversion effect by the alignment mark A1 on the first object surface and the alignment mark B1 on the second object surface, and the light beam is converted onto a predetermined surface. guide the light to
A position detection device characterized in that the incident position of the light beam on the predetermined surface is detected by a detection means, and positional deviation is detected using an output signal from the detection means. (2) When detecting a relative positional deviation between a first object and a second object that are arranged facing each other, two alignment marks A1 and A2 that perform a wavefront conversion action on the first object surface are moved in the positional deviation detection direction. Two alignment marks are provided along the second object surface and have a wavefront conversion effect on the second object surface. alignment mark A1 on the first object surface and alignment mark B1 on the second object surface among the light beams from the light projecting means. A first beam of light that has undergone a wavefront conversion effect at each of the alignment mark A2 on the first object surface and a second beam of light that has undergone a wavefront conversion effect of each of the alignment mark A2 on the first object surface and the alignment mark B2 on the second object surface, respectively, on a predetermined plane. Light is guided upward, the incident positions of the first light beam and the second light beam on the predetermined surface are detected by detection means, and positional deviation is detected using an output signal from the detection means. position detection device. (3) The position detection device according to claim 1, wherein each of the alignment marks A1 and B1 is made of a physical optical element that has an imaging function only in the positional deviation detection direction. (4) Alignment marks A1, A2, B1, B2
3. The position detecting device according to claim 2, wherein each of the plurality of position detecting devices comprises a physical optical element having an imaging function only in the positional deviation detection direction.