JP2002151676A - Image pickup device, its manufacturing method, alignment device, aligner, abberation measuring instrument, and method of manufacturing the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a need for a mechanical shutter from a back surface irradiation type image pickup device by improving the energy-ray detecting efficiency and smear generation of the device. SOLUTION: In this image pickup device, a charge storing section (17) is formed on the second face side of a double-face structure to face a charge transferring section (13) formed on the first face side of the structure. On the second face side of the storing section (17), a depletion inhibiting layer (18) is provided. The storing section (17) improves the energy-ray detecting efficiency and smear generation of the device by shortening the diffusing distance of signal charges. The depletion inhibiting layer (18) suppresses the occurrence of dark currents on the second surface side. The image picking-up quality of the device is further improved, by discharging reactive charges via the charge transferring section (13), while the storing section (17) stores charges. In addition, the blooming phenomenon of the device is improved by discharging excessive charges overflowing the brim of the storing section (17) through the transferring section (13). In a method of manufacturing this image pickup device, the alignment accuracy of the double-face structure is improved, by forming datum references on both faces, based on one alignment mark.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for receiving energy rays (visible light, ultraviolet rays, soft X-rays, electron beams, etc.) on one surface side (second surface side) of a semiconductor, and converting photoelectrically converted signal charges. Is transferred to the charge transfer section on the other surface side (first surface side) and read out. The present invention also relates to a method for manufacturing the imaging device, and a positioning device, an exposure device, and a wavefront aberration measurement device equipped with the imaging device. Further, the present invention relates to a method for manufacturing a device such as the above-described image pickup apparatus, which requires alignment of a double-sided structure.

[0002]

2. Description of the Related Art FIG. 14 is a diagram showing a conventional example of a back-illuminated type imaging device. In FIG. 14, the P-type semiconductor substrate 72 is set to a thickness of about 10 μm. An N-type CC is provided on the first surface side of the semiconductor base 72 for charge transfer.
The D diffusion layer 73 is provided in a long shape. In the vicinity of the CCD diffusion layer 73, a multilayer transfer electrode 75 is arranged via a gate oxide film 74. The semiconductor substrate 72 is provided with an antireflection film 79, a support substrate 81, and the like.

The imaging device 71 having such a configuration includes a second
Energy rays are irradiated from the surface side. An electron-hole pair is generated on the second surface side of the semiconductor substrate 72 by this energy ray. Some of these free electrons are transferred to the semiconductor substrate 72.
After moving inside, it reaches the potential well of the CCD diffusion layer 73 and is accumulated as signal charges. The signal charges in the CCD diffusion layer 73 are transferred by the voltage applied to the transfer electrode 75, and are sequentially read out.

[0004]

By the way, in such a back-illuminated type imaging device 71, free electrons generated on the second surface side in FIG. For this reason, there is a problem that electrons are easily recombined with holes and disappear, and the efficiency of detecting energy rays is reduced.

[0005] In addition, there is another problem that smears are liable to occur because the moving free electrons are mixed between adjacent pixels. The occurrence of such smear was a serious problem in narrowing the pixel pitch and increasing the number of pixels in the imaging device. In particular, short-wave energy rays such as ultraviolet rays generate electron-hole pairs in an extremely shallow region on the second surface side. for that reason,
In the case of an energy ray having a short wavelength, the moving distance of the free electrons is particularly long, and the above two problems have occurred more remarkably.

Further, in the conventional imaging device 71, even during the transfer of the signal charge, free electrons are mixed in from the second surface side.
It was necessary to completely shield the second surface from light. Therefore, there is a problem that a light-shielding mechanism such as a mechanical shutter is required. Further, in the conventional imaging device 71, there is a problem that a large number of dark currents are generated at the interface between (antireflection film 79) and (semiconductor substrate 72) and at the interface between (gate oxide film 74) and (CCD diffusion layer 73). There was a point. Such dark currents have caused adverse effects such as deterioration of imaging quality and inability to detect weak light.

Further, in the conventional image pickup device 71, a potential well (hereinafter referred to as a "backside well") is provided near the surface of the second surface due to the surface order and trapped charges.
Occurs. These backside wells capture electrons and reduce the efficiency of detecting energy rays.

In view of the above problems, the inventions according to the first to eleventh aspects are of a back-illuminated type in which energy beam detection efficiency is high, smear is small, and a mechanical shutter is not particularly required. It is a common object to provide an imaging device. Another object of the present invention is to provide a back-illuminated imaging device capable of suppressing dark current from the second surface side. It is an object of the present invention to provide a back-illuminated imaging device capable of suppressing dark current from the first surface side. It is an object of the present invention to provide a back-illuminated imaging device capable of suppressing dark current from the first surface side. It is an object of the present invention to provide a back-illuminated imaging device capable of suppressing the blooming phenomenon. It is another object of the present invention to provide a back-illuminated imaging device capable of reliably transferring the electric charge in the electric charge storage unit to the electric charge transfer unit. It is an object of the present invention to provide a back-illuminated imaging device capable of increasing the driving speed of charge transfer. It is another object of the present invention to provide a method of manufacturing the imaging device. It is an object of the present invention to provide a positioning device equipped with the imaging device.
It is an object of the invention according to claim 12 to provide an exposure apparatus equipped with the imaging device. It is an object of the present invention to provide a wavefront aberration measuring apparatus equipped with the imaging device. It is another object of the present invention to provide an exposure apparatus equipped with the wavefront aberration measuring device.

Incidentally, in order to manufacture the image pickup device according to the first to ninth aspects, the two-sided structure of the image pickup device must be aligned. Heretofore, a double-sided aligner or an infrared aligner has been indispensable to perform such alignment of the double-sided structure. That is, when a double-sided aligner is used, the structure of the other surface is formed while performing alignment using the alignment mark on the opposite surface side. When an infrared aligner is used, the alignment mark on the opposite surface is imaged through the other surface using infrared light so as to be visible. The structure of the other surface is formed while using the watermark image of the alignment mark as a reference for positioning.

However, with a double-sided aligner, ± 2
An alignment error of μm occurs. Also in the infrared aligner, a positioning error of ± 3 μm occurs. Such an alignment error occurs as a result of indirectly using the alignment mark on the opposite surface side, and it has been extremely difficult in principle to improve the alignment accuracy. Therefore, no matter which aligner is used, there is a problem that the two-sided structure cannot be precisely positioned. Therefore, in the case where the resolution of the imaging device described in claims 1 to 8 is further increased (miniaturization), problems such as yield are expected to occur.

Further, in the conventional manufacturing method, a special manufacturing apparatus equipped with a double-sided aligner or an infrared aligner is indispensable. Therefore, there is a problem that a device requiring alignment of the double-sided structure cannot be manufactured with a general manufacturing apparatus.

Therefore, the inventions of claims 13 to 20 provide a device manufacturing method suitable for manufacturing a device which requires alignment of the double-sided structure like the imaging apparatus of claims 1 to 9. The purpose is to:

[0013]

According to a first aspect of the present invention, a semiconductor substrate of a first conductivity type is formed on a first surface side of a semiconductor substrate. In a back-illuminated type imaging device having a charge transfer unit for transferring and reading signal charges generated by energy rays emitted from the opposite second surface side, in a back-illuminated imaging device, the charge transfer unit faces the charge transfer unit on the first surface side. A plurality of charge accumulation portions of a second conductivity type different from the first conductivity type, the signal accumulation portions being formed on the second surface side and accumulating signal charges generated by energy rays in pixel units; A depletion prevention layer provided to prevent a depletion region extending around the charge storage portion from reaching the second surface; and a charge transfer means for transferring signal charges stored in the charge storage portion to the charge transfer portion. It is characterized by having. In the above configuration, a region of the second conductivity type is formed for each pixel between the second surface, which is the light receiving surface, and the charge transfer portion, and is used as a charge storage portion. A potential well is formed by discharging charges from the charge storage unit to a charge transfer unit or the like. The potential well (charge storage unit) has a function of collecting signal charges generated on the second surface side for each pixel.

The moving distance of the electric charge on the second surface side is reduced by the width of the potential well by the pixel storage section. Therefore, the recombination of electric charges is suppressed by the shortened moving distance, and the efficiency of detecting energy rays is increased. Also, due to the synergistic effect of the action of shortening the moving distance and the action of once collecting signal charges in pixel units in the charge storage section, the chance of mixing signal charges between adjacent pixels is surely reduced, and smear is generated. Is suppressed.

Further, in the above configuration, the free flow of signal charges can be blocked by arranging the charge storage units on the second surface side of the charge transfer units. Accordingly, during the signal charge transfer of the charge transfer unit, the signal charge newly generated on the second surface side is stored in the charge storage unit, so that there is little risk of being mixed into the charge transfer unit, and the mechanical shutter can be omitted. become.

In the invention according to the first aspect, the depletion preventing layer is provided on the second surface side of the charge storage portion. The depletion prevention layer prevents a depletion region generated in the charge storage portion from reaching the surface of the second surface. Therefore, most of the dark current randomly generated at the interface of the second surface is diffused and recombined in the depletion prevention layer before arriving at the charge accumulation portion, and disappears. Therefore, it is possible to capture a good image with a small dark current.

[Claim 2] The invention according to claim 2 is the imaging device according to claim 1, wherein the depletion prevention layer is a first conductivity type layer. Since the depletion prevention layer having the above configuration is of the first conductivity type, it is particularly effective in filling the above-mentioned back side well and improving the efficiency of detecting energy rays.

[Claim 3] According to a third aspect of the present invention, in the imaging device according to the first or second aspect, the depletion preventing layer is provided with an impurity distribution (impurity profile; (Concentration and layer thickness) and an impurity concentration that can prevent the depletion region from reaching the second surface. By setting such a depletion prevention layer, most of the energy rays efficiently pass through the depletion prevention layer, and generate signal charges in the depletion region of the charge storage portion. Therefore, it is possible to reliably increase the energy ray detection efficiency.

According to a fourth aspect of the present invention, in the imaging device according to any one of the first to third aspects, the charge storage section is completely depleted when the charge transfer is completed. With this complete depletion, afterimages can be significantly reduced. Note that the above-described depletion prevention layer has an effect of facilitating realization of the complete depletion.

In a fifth aspect of the present invention, a semiconductor substrate of the first conductivity type and a second surface formed on the first surface side of the semiconductor substrate and opposite to the first surface side are provided. And a charge transfer unit for transferring and reading out signal charges generated by energy rays emitted from the side, the back surface-illuminated type imaging device includes a charge transfer unit on the second surface facing the charge transfer unit on the first surface. A plurality of charge accumulation units of a second conductivity type different from the first conductivity type, each of which accumulates a signal charge generated by an energy ray in a pixel unit, and transfers the signal charges accumulated in the charge accumulation unit to the charge transfer unit. And a charge transfer unit that drives the charge transfer unit to discharge the invalid charge during the accumulation period of the signal charge by the charge storage unit. In the above configuration, the invalid charge discharging unit sweeps out the invalid charges in the charge transfer unit during the period when the charge storage unit is storing the signal charges. Therefore, there is no possibility that the dark current generated on the first surface side stays in the charge transfer unit, and an imaging device with a small dark current is realized. The invalid charge discharging unit may drive the charge transfer unit and the charge transfer unit to transfer and discharge the invalid charge in the charge storage unit at an appropriate timing. In this case, it is possible to adjust the signal charge accumulation time (that is, the exposure time) in the charge accumulation unit, and the electronic shutter function is realized.

[Claim 6] The invention according to claim 6 is directed to a semiconductor substrate of the first conductivity type and a second surface formed on the first surface side of the semiconductor substrate and opposite to the first surface side. And a charge transfer unit for transferring and reading out signal charges generated by energy rays emitted from the side, the back surface-illuminated type imaging device includes a charge transfer unit on the second surface facing the charge transfer unit on the first surface. A plurality of charge accumulation units of a second conductivity type different from the first conductivity type, each of which accumulates a signal charge generated by an energy ray in a pixel unit, and transfers the signal charges accumulated in the charge accumulation unit to the charge transfer unit. And at least a predetermined period during the signal charge accumulation period by the charge accumulation unit, the potential of the first surface side of the charge transfer unit is brought close to the substrate potential to prevent the inflow of dark current from the first surface side. Dark current suppression means And butterflies. In the above configuration, the dark current suppressing unit performs a potential operation such that the potential on the first surface side of the charge transfer unit approaches the substrate potential. By such potential operation, surface depletion on the first surface side is avoided, and the possibility that dark current on the first surface side is mixed into the charge transfer unit is reduced.

<Seventh Aspect> The invention according to the seventh aspect is directed to a semiconductor substrate of a first conductivity type and a second surface formed on the first surface side of the semiconductor substrate and opposite to the first surface side. And a charge transfer unit for transferring and reading out signal charges generated by energy rays emitted from the side, the back surface-illuminated type imaging device includes a charge transfer unit on the second surface facing the charge transfer unit on the first surface. A plurality of charge accumulation units of a second conductivity type different from the first conductivity type, each of which accumulates a signal charge generated by an energy ray in a pixel unit, and transfers the signal charges accumulated in the charge accumulation unit to the charge transfer unit. Charge transfer means, and excess charge discharging means for discharging excess charge by overflowing excess charge generated beyond the saturated charge amount of the charge storage section to the charge transfer section and driving the charge transfer section. Features. In the above configuration, the excess charge discharging unit discharges the excess charge overflowing from the charge storage unit via the charge transfer unit. Therefore, the possibility that the excess charge overflows to the charge storage portion of the adjacent pixel is reduced, and the blooming phenomenon can be reliably suppressed.

<Eighth Aspect> According to an eighth aspect of the present invention, there is provided a semiconductor substrate of a first conductivity type, and a second surface formed on the first surface side of the semiconductor substrate and opposite to the first surface side. And a charge transfer unit for transferring and reading out signal charges generated by energy rays emitted from the side, the back surface-illuminated type imaging device includes a charge transfer unit on the second surface facing the charge transfer unit on the first surface. A plurality of charge accumulation units of a second conductivity type different from the first conductivity type, each of which accumulates a signal charge generated by an energy ray in a pixel unit, and transfers the signal charges accumulated in the charge accumulation unit to the charge transfer unit. Charge transfer means for transferring the charge of the charge storage section to the charge transfer section by controlling the potential of the charge storage section by applying a voltage to the semiconductor substrate. And In the above configuration, the signal charge is transferred from the charge storage unit to the charge transfer unit by directly operating the substrate potential of the semiconductor substrate. Therefore, control such as complete depletion of the charge storage portion is facilitated, and the signal charge transfer operation becomes more reliable. As a result, there is little fear that signal charges remain in the charge storage portion and an afterimage phenomenon occurs, and it is possible to sufficiently cope with a charge storage portion having a large saturated charge amount.

<Seventh Aspect> According to a ninth aspect of the present invention, in the imaging device according to the ninth aspect, the semiconductor substrate is a second semiconductor device.
It has a well structure surrounded by a conductive semiconductor region. In the above configuration, the semiconductor substrate is electrically isolated from the surroundings by the well structure. Therefore, the dimensions of the semiconductor substrate are not so large, and the capacitance of the semiconductor substrate can be appropriately reduced. Therefore, the substrate potential can be controlled at a high speed when applying a voltage to the semiconductor substrate, and the transfer operation from the charge storage unit to the charge transfer unit can be further speeded up.

[Claim 10] The invention according to claim 10 is a manufacturing method for manufacturing a back-illuminated imaging device, comprising: a thinning step of thinning a first conductive type semiconductor substrate; Forming a plurality of charge accumulation portions of a second conductivity type different from the first conductivity type on one surface side of the semiconductor substrate thus formed; and forming a charge accumulation portion on one surface side of the thinned semiconductor substrate. First to prevent surface depletion due to accumulation
Forming a conductive type depletion preventing layer. In the above manufacturing method, since the charge storage portion and the depletion prevention layer are formed from the second surface side, the surface depth of the charge storage portion can be accurately controlled. Therefore, fine adjustments such as setting the surface depth of the charge storage portion as shallow as possible to enhance the efficiency of detecting short-wavelength energy rays are further facilitated. Further, since the depletion prevention layer is formed from the second surface side, the thickness and impurity concentration of the depletion prevention layer are stabilized, and a back-illuminated imaging device with a smaller dark current can be manufactured.

<Eleventh aspect> According to an eleventh aspect of the present invention, there is provided the imaging apparatus according to any one of the first to ninth aspects, and an object or a mark formed on the object using the imaging apparatus. And a position detection unit that detects position information of the object based on the captured image, based on the position information,
A position control unit for positioning the object. By using the imaging device according to the first to ninth aspects, it is possible to improve the detection accuracy of the position information. Therefore, the positioning accuracy of the object can be further improved.

In a twelfth aspect of the present invention, there is provided the positioning device according to the eleventh aspect, and an exposure unit for exposing a predetermined pattern to a substrate which is an object positioned by the positioning device. And characterized in that: By using the positioning device according to the eleventh aspect, it is possible to improve the positioning accuracy of the substrate. Therefore, it is possible to further improve the exposure position accuracy of the substrate by the exposure apparatus.

(13) A device manufacturing method according to the above (13), wherein a mark forming step of forming a first alignment mark on the first surface side of the substrate and a device base on the first surface side of the substrate are provided. A base forming step of forming a portion, and a “concave or convex portion on the first surface side of the base portion” generated by a concave or convex portion of the first alignment mark in the base forming step is referred to as a position reference. A first surface side processing step of forming a predetermined structure on one surface side;
A removing step of removing the substrate from the second surface side opposite to the surface side, and positioning a second alignment mark (a reversal mark of the first alignment mark) appearing on the second surface side of the base portion in the removing step. As a reference, a second surface side processing step of forming a predetermined structure is provided on the second surface side of the base portion.

In the above device manufacturing method, the first substrate
A first alignment mark is formed on the surface side, and a base portion of the device is formed on the first alignment mark. At this time, the unevenness of the first alignment mark appears as a mark of the unevenness (hereinafter referred to as “history”) on the first surface side of the base portion. This history is aligned with the first alignment mark.
Therefore, by using this history as a position reference, it is possible to form a device structure that is aligned with the first alignment mark on the first surface side of the base portion.

Subsequently, the substrate is removed from the second surface side of the base portion. At this time, a second alignment mark appears as a removal mark of the first alignment mark on the second surface side of the base portion. This second alignment mark is aligned with the first alignment mark. Therefore, by using the second alignment mark as a position reference, a device structure that is aligned with the first alignment mark can be formed on the second surface side of the base portion.

As described above, a device structure that is aligned with the first alignment mark is formed on both the first surface side and the second surface side. Therefore, it is possible to manufacture a device in which the position is precisely aligned between the two-sided structures.

Further, in the above-described device manufacturing method, the device structure of each surface is formed according to the position reference (history, second alignment mark) of the surface. Therefore, it is not necessary to use the alignment mark on the opposite side as a position reference, and a conventional double-sided aligner or infrared aligner is not particularly required. Therefore, it is possible to manufacture a device that requires alignment of the double-sided structure using a general manufacturing apparatus.

In the specification of the present application, the expression "○ as a reference (of position) .." also includes the meaning of "using the history of XX or a retouched mark as a reference (of position)." It is.

According to a fourteenth aspect of the present invention, in the device manufacturing method, a base forming step of forming a base part of the device on the first surface side of the substrate, and the device reaches the substrate and can be selectively removed. Forming an area to be removed in the base portion, forming a first alignment mark on the first surface side of the area to be removed, and using the first alignment mark as a position reference. A first surface side processing step of forming a predetermined structure on the first surface side of the base portion, a layer forming step of forming a layer so as to cover at least the first alignment mark, and a first surface of the base portion A removing step of removing the substrate and the area to be removed from the second surface side opposite to the side, and a second alignment mark (a reversal mark of the first alignment mark) appearing on the second surface side in the removing step
And a second surface side processing step of forming a predetermined structure on the second surface side of the base portion with reference to the position.

In the above device manufacturing method, the first substrate
A base portion of the device is formed on the surface side. An area to be removed reaching the substrate is formed in the base portion during or after the formation step. Further, on the first surface side of the area to be removed,
A first alignment mark is formed. The device structure is formed on the first surface side of the base portion using the first alignment mark as a position reference. Accordingly, a device structure that is aligned with the first alignment mark is formed on the first surface side of the base portion.

In the process of forming such a base portion or device structure, if a layer is formed so as to cover the first alignment mark, the process becomes a layer forming process. On the other hand, when such a layer is not particularly formed, a layer forming step is separately performed. With the first alignment mark covered in this manner, the substrate is removed from the second surface side of the base portion. At this time, it is preferable that the region to be removed is removed together. However, if the removal scheduled area is not removed at the same time, the removal scheduled area is separately removed.

The second alignment mark in which the unevenness of the first alignment mark is inverted appears in the removal mark of the area to be removed. This second alignment mark is aligned with the first alignment mark. Therefore, by using the second alignment mark as a position reference, a device structure that is aligned with the first alignment mark can be formed on the second surface side of the base portion.

As described above, a device structure that is aligned with the first alignment mark is formed on both the first surface side and the second surface side. Therefore, it is possible to manufacture a device in which the position is precisely aligned between the two-sided structures. Further, in the above device manufacturing method,
The device structure on each surface is formed according to the position reference (first alignment mark, second alignment mark) on that surface. Therefore, it is not necessary to use the alignment mark on the opposite side as a position reference, and a conventional double-sided aligner or infrared aligner is not particularly required. Therefore, it is possible to manufacture a device that requires alignment of the double-sided structure using a general manufacturing apparatus.

(15) A device manufacturing method according to (15), wherein a mark forming step of forming a first alignment mark on the first surface side of the substrate, and a base portion of the device on the first surface side of the substrate Forming a base on the first surface side of the base portion with reference to the position of the recess or protrusion on the first surface side of the base portion caused by the recess or protrusion of the first alignment mark in the base forming step. Forming a second alignment mark (a re-alignment mark of the first alignment mark) (re-aligning step); and using a predetermined structure on the first surface side of the base portion using the second alignment mark as a position reference. And a forming process. In the above device manufacturing method, a first alignment mark is formed on the first surface side of the substrate, and a base portion of the device is formed on the first alignment mark. At this time, the unevenness of the first alignment mark appears as a history on the first surface side of the base portion. This history is aligned with the first alignment mark. Therefore, using this history as a position reference,
A rework mark is formed. By using the reworked mark as a reference for the position, the first surface side of the base portion is
It is possible to form a device structure that is aligned with the alignment mark.

[Claim 16] A device manufacturing method according to claim 16, wherein a mark forming step of forming a concave or convex first alignment mark on the first surface side of the substrate, and a mark forming step of forming a first alignment mark on the first surface side of the substrate A base forming step of forming a base portion of the device; and removing a substrate from a second surface side of the base portion opposite to the first surface side to form a second alignment on the second surface side of the base portion. Removing a mark (inversion mark of the first alignment mark) to appear, and forming a predetermined structure on the second surface side of the base portion using the second alignment mark as a position reference. And characterized in that: In the above device manufacturing method, a first alignment mark is formed on the first surface side of the substrate, and a base portion of the device is formed on the first alignment mark. After that, the substrate is removed. By the removal of the substrate, a second alignment mark, which is a reversal mark of the first alignment mark, appears on the second surface side of the base portion. A device structure is formed on the base portion using the second alignment mark as a position reference. According to such a manufacturing method, it is possible to form a device structure that is aligned with the first alignment mark on the second surface side of the base portion.

[Claim 17] In the device manufacturing method according to claim 17, a base forming step of forming a base portion of the device on the first surface side of the substrate, and a step of reaching the substrate and being selectively removable. Forming a layer to cover at least the first alignment mark; forming a layer to cover at least the first alignment mark;
A removing step of removing the substrate and the area to be removed from the second surface side opposite to the surface side, and causing a second alignment mark (removal mark of the area to be removed) to appear on the second surface side of the base portion;
A step of forming a predetermined structure on the second surface side of the base portion using the second alignment mark as a position reference.

In the above device manufacturing method, the first substrate
A base portion of the device is formed on the surface side. During the formation step or after the formation, a region to be removed penetrating to the substrate is formed by patterning. The pattern of the region to be removed is formed according to the position reference on the first surface side. Therefore, the pattern of the region to be removed can be naturally aligned with the device structure on the first surface side that also uses this position reference.

In the process of forming such a base portion, if a layer is formed so as to cover a region to be removed, the process is a layer forming process. On the other hand, when such a layer is not particularly formed, a layer forming step is separately performed to form a layer so as to cover the region to be removed. Thereafter, the substrate is removed from the second surface side of the base portion. At this time, it is preferable that the region to be removed is removed together. However, if the removal scheduled area is not removed at the same time, the removal scheduled area is separately removed.

By removing the area to be removed, a second alignment mark appears on the second surface side of the base portion. The second alignment mark is a removal mark of an area to be removed formed from the first surface side, and is aligned with the device structure on the first surface side. Therefore, by using the second alignment mark as a reference for the position, it is possible to form a device structure on the second surface side of the base portion that is aligned with the device structure on the first surface side.

As a result, it is possible to manufacture a device in which the positional alignment between the two-sided structures is precisely adjusted. Further, in the above-described device manufacturing method, the device structure on each surface is formed according to the position reference of the surface (the position reference on the first surface, the alignment mark on the second surface). Therefore, it is not necessary to use the alignment mark on the opposite side as a position reference, and a conventional double-sided aligner or infrared aligner is not particularly required. Therefore, it is possible to manufacture a device that requires alignment of the double-sided structure using a general manufacturing apparatus.

In the above description, the case where a device structure is formed on the first surface side has been described in order to more generally explain the operation of the present invention. However, a feature of the present invention is that a region to be removed is formed in advance from the first surface side so that the second alignment mark appears on the second surface side as the substrate is removed. According to the features of the present invention, a remarkable operation and effect can be obtained in that it is not necessary to newly form an alignment mark when the manufacturing process is shifted from the first surface to the second surface. Therefore, the operation of forming the device structure on the first surface side in the above description is not an essential step but an arbitrary step.

[Claim 18] A device manufacturing method according to claim 18, wherein a base forming step of forming a base portion of the device on the first surface side of the substrate; A step of forming a scheduled opening area that reaches the substrate and selectively removes the scheduled opening area at the scheduled opening of the base portion; and a second surface side of the base portion opposite to the first surface side. The substrate and the area to be opened are removed, and the second portion of the base portion is removed.
And a removing step of forming an opening hole (removal mark of the expected opening area) on the surface side.

In the above device manufacturing method, the first substrate
A base portion of the device is formed on the surface side. During or after the formation of the base portion, a region to be opened which penetrates to the substrate is formed at a position where the base portion is to be opened. Thereafter, the substrate is removed from the second surface side of the base portion. At this time, it is preferable that the planned opening region is removed together.
However, if the planned opening area is not removed at the same time, the planned opening area is separately removed. An opening hole appears on the second surface side of the base portion as a trace of removal of the opening area. Since the opening hole is buried in advance from the first surface side as an expected opening region, it is possible to easily align the device structure on the first surface side with the opening hole.

[Claim 19] In the device manufacturing method according to claim 19, in the device manufacturing method according to any one of claims 13, 15, 16, and 17, It contains antimony (Sb).

(Claim 20) In the device manufacturing method according to the twentieth aspect, in the device manufacturing method according to any one of the fourteenth and seventeenth aspects, the step of forming a region to be removed is performed using antimony (Sb). The region to be removed is formed using a material containing

A twenty-first aspect of the present invention provides an aberration measuring device, wherein the imaging device according to any one of the first to ninth aspects and a light beam for aberration measurement is emitted to an optical system to be measured. Aberration measurement optical system, and the light beam that has passed through the test optical system,
A condensing lens that condenses light on the imaging surface of the imaging device, and a position detection unit that detects position information of the light beam condensed on the imaging surface,
A calculating unit for obtaining the aberration of the optical system to be detected based on the detection result by the position detecting unit.

[Claim 22] An exposure apparatus according to claim 22 has the aberration measuring apparatus according to claim 21 and a projection optical system to be subjected to aberration measurement by the aberration measuring apparatus. .

[0053]

Embodiments of the present invention will be described below with reference to the drawings.

<< First Embodiment >> The first embodiment is an embodiment corresponding to the invention described in claims 1 to 7, 10, 17, 19, and 20.

[Configuration of Imaging Apparatus 11] FIG. 1 is a schematic view of the imaging apparatus 11 as viewed from the second surface side. FIG. 2 is a cross-sectional view of the imaging device 11 taken along the line AA ′. Hereinafter, FIGS. 1 and 2
The configuration of the imaging device 11 will be described with reference to FIG. First, the imaging device 11 is provided with a P-type semiconductor substrate 12. On the first surface side of the semiconductor substrate 12, an N-type CCD diffusion layer 13 is embedded in units of pixel columns. In the vicinity of the CCD diffusion layer 13, a multilayer transfer electrode 15 is arranged via a gate oxide film 14. The voltage of these transfer electrodes 15 is
It is controlled by the vertical transfer unit 16. At the output end of the CCD diffusion layer 13, a horizontal CCD unit 24 is disposed.
On the other hand, the semiconductor substrate 1 faces the CCD diffusion layer 13.
An N-type charge storage portion 17 is embedded in a pixel unit on the second surface side 2. These charge accumulating portions 17 are electrically separated via a P + type buried channel stop 17a. Further on the second surface side of the charge storage section 17, a P-type depletion prevention layer 18 is provided. This depletion prevention layer 18
Is set to a thickness that allows the energy beam to be detected to sufficiently pass therethrough, and that the impurity concentration is such that the surface depletion of the charge storage portion 17 is prevented. In addition, the imaging device 11 includes:
An antireflection film 19, an AL pad 20, a support substrate 21, and the like are provided.

[Correspondence between the present invention and the first embodiment]
Hereinafter, the correspondence between the present invention and the first embodiment will be described. Regarding the correspondence between the inventions described in claims 1 to 4 and the first embodiment, the semiconductor substrate corresponds to the semiconductor substrate 12, and the charge transfer portion corresponds to the CCD diffusion layer 13, the gate oxide film 14 and the transfer electrode 15. The charge storage section corresponds to the charge storage section 17, the depletion prevention layer corresponds to the depletion prevention layer 18, and the charge transfer means operates by the vertical transfer section 16 “by controlling the voltage of the transfer electrode 15. Signal charge of C
Transfer Function to CD Diffusion Layer 13 ". Claim 5
As for the correspondence between the invention described in (1) and the first embodiment, in addition to the correspondence described above, the invalid charge discharging means is provided with a function of “discharge of invalid charge through the CCD diffusion layer 13 by the vertical transfer unit 16. Corresponding to. As for the correspondence between the invention described in claim 6 and the first embodiment, in addition to the correspondence described above, the dark current suppressing means may be configured such that the vertical transfer unit 16 uses the “potential on the first surface side of the CCD diffusion layer 13. To bring the dark current closer to the substrate potential to suppress the inflow of dark current. Regarding the correspondence between the invention described in claim 7 and the first embodiment, in addition to the above-mentioned correspondence, the excess charge discharging means may be configured to perform “the excess charge overflowing from the charge accumulation unit 17 by the vertical transfer unit 16. Discharge function via the CCD diffusion layer 13 ".

[First Manufacturing Method] FIGS. 3 and 4 are views for explaining a first manufacturing method of the imaging device 11. Hereinafter, a first manufacturing method of the imaging device 11 will be described with reference to FIGS. Here, the description of the photolithography step and other known steps will be omitted.

First, for a P + type substrate 30 having a concentration of about 1E18 / cm ³ , a concentration of 1E15 / cm ³ and a thickness of 4 μm
About P-type epitaxial layer 31 is vapor-phase grown. Note that a step (due to dry etching or a difference in oxidation rate) is formed on a part of the surface of the P-type epitaxial layer 31,
Used as an alignment mark (not shown). After a protection oxide film is formed on the P-type epitaxial layer 31, an acceleration voltage of 180 KeV and a dose of 7
As ions are implanted under the condition of E11 / cm ² to form a region to be the charge storage portion 17. Furthermore, an acceleration voltage of 60K
B ions are implanted under the conditions of eV and a dose of 1E13 / cm ² to form a region serving as a channel stop 17a.
Thereafter, an annealing process is performed to remove the protection oxide film, thereby obtaining the state shown in FIG. 3A.

Next, a P-type epitaxial layer 32 having a concentration of 1E15 / cm ³ and a thickness of about 4 μm is vapor-phase grown on the surface of the P-type epitaxial layer 31. Note that the concentration and thickness of the P-type epitaxial layer 32
During the transfer operation, the CCD diffusion layer 13 and the charge storage section 17
Are determined so as to satisfy the condition that they are electrically separated from each other. Therefore, when the thickness of the P-type epitaxial layer 32 is, for example, about 6 μm, the concentration condition is 5E14 / c.
About m ³ is preferable.

Next, after changing the alignment mark of the P-type epitaxial layer 31, the CCD diffusion layer 13, the gate oxide film 14, the transfer electrode 15 and the like are formed in the same procedure as that of the frame transfer type CCD. afterwards,
The semiconductor substrate shown in FIG. 3B is obtained through a planarization process, a process for forming an AL wiring, a passivation film, and the like. Next, the semiconductor substrate is subjected to SOG (Spin On Glass) processing or the like, and the upper surface from the epitaxial layer is flattened to a thickness of about 10 μm. If necessary, CMP (Chemical Mec.
hanical Polishing) or flattening processing such as mechanical polishing. Thereafter, a low-concentration silicon substrate serving as the support substrate 21 is attached to obtain a state shown in FIG. 3C.

Next, etching is performed in a solution of hydrofluoric acid 1: nitric acid 3: acetic acid 8 to remove the P + type substrate 30. Here, the etching is controlled using the fact that the etching rate of P + silicon is faster than that of P- silicon. At this time, 1E17 / cm ^{3 at} which the etching rate becomes slower
A certain layer region remains at the interface of the P-type epitaxial layer 31 and becomes the depletion prevention layer 18. FIG. 4D shows the state up to this point.
Shown in

Next, the antireflection film 19 is formed by the sputtering method, and the state shown in FIG. 4E is obtained. Thereafter, the silicon in the pad portion is opened by dry etching or the like, and the image pickup device 11 is completed through processes such as dicing and packaging.

The present inventor has found another suitable condition through further experiments. Hereinafter, another condition will be described.

[0064] First, the concentration of 1E18 / cm ³ order of P + -type substrate 30, concentration 3E15 / cm ^3, a thickness of 4μm
About P-type epitaxial layer 31 is vapor-phase grown. Note that a step (due to dry etching or a difference in oxidation rate) is formed on a part of the surface of the P-type epitaxial layer 31,
Used as an alignment mark (not shown). After forming a protective oxide film on the P-type epitaxial layer 31, an acceleration voltage of 180 KeV and a dose of 6
As ions are implanted under the condition of E12 / cm ² to form a region to be the charge storage portion 17. Furthermore, an acceleration voltage of 60K
B ions are implanted under the conditions of eV and a dose of 1E13 / cm ² to form a region serving as a channel stop 17a.
Thereafter, an annealing process is performed to remove the protection oxide film, thereby obtaining the state shown in FIG. 3A.

Next, a P-type epitaxial layer 32 having a concentration of 3E15 / cm ³ and a thickness of about 3 μm is vapor-phase grown on the surface of the P-type epitaxial layer 31. Note that the concentration and thickness of the P-type epitaxial layer 32
During the transfer operation, the CCD diffusion layer 13 and the charge storage section 17
Are determined so as to satisfy the condition that they are electrically separated from each other. Therefore, when the thickness of the P-type epitaxial layer 32 is, for example, about 6 μm, the concentration condition is 5E14 / c.
About m ³ is preferable. The subsequent processing (such as the processing for forming the CCD diffusion layer 13) is performed in the same manner as described above.

[Second Manufacturing Method] FIGS. 5 and 6 are views for explaining a second manufacturing method of the imaging device 11. Hereinafter, the second manufacturing method will be described with reference to FIGS. First, a P + type substrate 40 having a concentration of about 1E18 / cm ³
With a concentration of 5E14 / cm ³ and a thickness of about 4 μm
Type epitaxial layer 41 is grown by vapor phase.
).

Here, a P + -type impurity region 42 is formed in a part of the P-type epitaxial layer 41 by ion implantation or thermal diffusion (corresponding to a step of forming a region to be removed according to claim 17). FIG. 5A shows the state up to this point.

The impurity region 42 may be a high-concentration impurity region, and may be an N + type impurity region. For example, the N-type impurity of the impurity region 42 is Sb
(Antimony) is preferred. Further, the concentration of Sb is preferably 1E18 / cm ³ or more. Where S
The reason why b is preferable is that the post-process (P-type epitaxial layer 4
This is because, in the vapor phase growth of No. 3, auto-doping (phenomenon in which impurities in the substrate jump out into the atmosphere due to high temperature and are re-doped into the grown layer) can be suppressed. This auto-doping greatly affects the shape of the impurity region 42. As a result, the shape of an alignment mark 44 to be described later may be significantly deformed, and may not function as a mark. However, the above-described Sb has a property that this auto-doping hardly occurs. Therefore, by selecting Sb as the impurity of the impurity region 42, it becomes possible to form the alignment mark 44 in a good shape.

Next, on the P-type epitaxial layer 41,
A P-type epitaxial layer 43 having a concentration of 5E14 / cm ³ and a thickness of about 4 μm is further vapor-phase grown (corresponding to the base forming step and the layer forming step of claim 17). On the P-type epitaxial layer 43, the CCD diffusion layer 13, the gate oxide film 14, the transfer electrode 15, and the like are formed in the same procedure as that of the frame transfer type CCD. After that, a flattening step, a process of forming an AL wiring, a passivation film, and the like are performed to obtain a semiconductor substrate shown in FIG. 5B.

Next, SOG (Spin On
A flattening process such as glass is performed to adjust the thickness from the epitaxial layer to about 10 μm. If necessary, a flattening process such as CMP (Chemical Mechanical Polishing) or mechanical polishing is performed. Then, the supporting substrate 21
Then, a low-concentration silicon substrate is bonded to obtain a state shown in FIG. 5C.

Next, etching is performed in a solution of hydrofluoric acid 1: nitric acid 3: acetic acid 8 to remove the P + type substrate 40 (corresponding to a thinning step according to claim 10). At this time, the high-concentration P + type impurity region 42 is also removed, and an alignment mark 44 is formed (corresponding to the removing step according to claim 17). The alignment mark 44 is used in the following processing step on the second surface side (corresponding to the processing step described in claim 17), that is, in forming the charge storage portion 17, the channel stop 17a, the depletion prevention layer 18, and the like. Used in the alignment process.

First, after forming a protection oxide film on the second surface side of the P-type epitaxial layer 41, the acceleration voltage 180
As ions are implanted under the conditions of KeV and a dose of 3E12 / cm ² to form a region to be the charge storage portion 17 (corresponding to the storage portion forming step according to claim 10). further,
B ions are implanted under the conditions of an acceleration voltage of 150 KeV and a dose of 1E13 / cm ² to form a region serving as a channel stop 17a.

Further, boron fluoride is ion-implanted under the conditions of an acceleration voltage of 120 KeV and a dose of 3E13 / cm ² to form a region serving as a depletion prevention layer 18.
0). The impurity region thus formed is locally annealed with a laser or the like so that the AL wiring and the like are not exposed to a high temperature. The state so far is shown in FIG. 6d. Next, an antireflection film 19 is formed by a sputtering method, and a pad opening is made from the second surface side to obtain a state of FIG. 6E. After that, through processes such as dicing and packaging, the imaging device 11 is completed.

[Description of Operation of Imaging Apparatus 11] FIGS.
6 is a potential diagram for explaining the operation of the imaging device 11. FIG. Hereinafter, the operation of the imaging device 11 will be described with reference to these potential diagrams. First, as shown in FIG. 7, most of the energy rays penetrate the depletion prevention layer 18 and reach the depletion region of the charge storage unit 17 to generate electron-hole pairs. The free electrons generated at this time are attracted and stored in the potential well of the charge storage unit 17 and become signal charges. On the other hand, when the interface between the antireflection film 19 and silicon is depleted, a large number of dark currents are generated.
However, in the present invention, a depletion preventing layer exists at this interface. Therefore, it is possible to suppress (prevent) the dark current from being mixed into the charge storage portion.

The reason for such a deterrent effect is, for example, that the surface potential is fixed at the substrate potential,
Dark current hardly occurs. While the dark current diffuses and moves in the depletion preventing layer 18, it recombines and disappears. And so on.

If the charge accumulation time is extended in detecting weak light, the dark current accumulated in the CCD diffusion layer 13 cannot be ignored. Therefore, during the charge accumulation period, the vertical transfer section 16 sequentially applies a transfer voltage to the transfer electrode 15 to discharge invalid charges in the CCD diffusion layer 13 and suppress dark current as much as possible.

Further, the vertical transfer section 16 fixes the transfer electrodes 15 to a negative voltage sequentially with respect to the pixels from which the invalid charges have been discharged, and brings the surface potential of the CCD diffusion layer 13 closer to the substrate potential. By such an operation, holes gather around the surface of the CCD diffusion layer 13 and the surface depletion of the CCD diffusion layer 13 is prevented. As a result, as shown in FIG. 8, it is possible to greatly suppress the dark current mixed in the CCD diffusion layer 13 during the period of applying the negative voltage.

[0078] By either or both of these effects,
Even when the weak light is accumulated for a long time, the dark current can be suppressed to a negligible level. On the other hand, when strong light is applied, the potential well of the charge storage unit 17 is saturated and excess charge overflows. In a conventional back-illuminated imaging device, a phenomenon in which an excess charge overflows from a potential well of a CCD diffusion layer to blur a captured image (so-called blooming)
In order to avoid this, a horizontal overflow drain is provided. Therefore, conventionally, the aperture ratio of the imaging device has to be sacrificed by the area of the horizontal overflow drain.

However, in the image pickup device 11 of the present invention, as shown in FIG. 9, the voltage applied to the transfer electrode 15 is adjusted, and the excess charge overflowing the charge storage section 17 overflows to the CCD diffusion layer 13. This excess charge is discharged to the outside together with the dark current described above. Therefore, the blooming phenomenon can be improved without sacrificing the aperture ratio of the imaging device.

As described above, when the charge accumulation time ends, the vertical transfer section 16 applies a voltage of about 15 V to the transfer electrode 15. By this voltage application, as shown in FIG. 10, the signal charges in the charge storage unit 17 are drawn, and
It is transferred to each potential well of the D diffusion layer 13 in pixel units. At this time, the charge storage section 17 is completely depleted. Subsequently, as shown in FIG. 10, the vertical transfer unit 16 sequentially applies a transfer voltage of about ± 5 V to the transfer electrode 15 and sequentially reads out signal charges in the CCD diffusion layer 13.

[Effects of First Embodiment, etc.] In the first embodiment described above, the charge accumulation section 17 is provided on the second surface side opposite to the CCD diffusion layer 13. Therefore, it is possible to substantially reduce the moving distance of the signal charge on the second surface side. As a result, it is possible to improve the energy ray detection efficiency and the smear generation. In particular, when the moving distance is long (when signal charges are generated in an extremely shallow region of the second surface such as when ultraviolet rays are incident), the above-described improvement effect is remarkably exhibited.

In the first embodiment, the dark current is largely suppressed by the synergistic effects of the depletion prevention layer 18, the discharge of the dark current, and the prevention of the surface depletion of the CCD diffusion layer 13. Therefore, even under severe conditions such as detection of weak light, relatively good imaging quality can be obtained.

Further, in the first embodiment, the provision of the depletion prevention layer 18 makes it possible to remove the back side well on the second surface side. Therefore, there is little possibility that signal charges are trapped in the back side well,
Energy beam detection efficiency can be further improved.

In the first embodiment, the charge storage unit 1
Excess charges overflowing from the gate 7 are discharged through the CCD diffusion layer 13. Therefore, it is possible to reliably suppress the blooming phenomenon due to the excess charge.

Furthermore, in the first embodiment, since the free flow of signal charges is blocked by the charge storage units 17 arranged on the second surface side, charges may be mixed into the CCD diffusion layer 13 during charge transfer. Few. Therefore, there is no need to shield the second surface from light during charge transfer, and a mechanical shutter can be omitted. In particular, a high shielding effect can be obtained in a case where signal charges are generated in an extremely shallow region of the second surface, such as when ultraviolet rays are incident.

In the second manufacturing method described above, the second
Since the charge storage portion 17 and the depletion prevention layer 18 are formed from the surface side, it is possible to precisely control the surface depth of the depletion prevention layer 18 and the like.

Further, in the above-described second manufacturing method, the P + type impurity region 42 is formed at the time of processing the first surface side of the imaging device 11.
Is embedded. Thereafter, the P + type impurity region 42
Is removed from the second surface side to form an alignment mark 44 on the second surface side of the imaging device 11. By using the alignment mark 44 as a reference for the position, it is possible to form a device structure on the second surface side of the imaging device 11 that is in alignment with the processing on the first surface side. Next, another embodiment will be described.

<< Second Embodiment >> A second embodiment is an embodiment corresponding to the first to tenth aspects of the present invention.
FIG. 11 is a cross-sectional view of an imaging device 51 according to the second embodiment. In addition, about the structure common to 1st Embodiment (FIG. 2), the same code | symbol is attached | subjected to FIG. 11 and the description here is abbreviate | omitted.

A characteristic feature of the structure of the imaging device 51 is that the semiconductor substrate 12 is surrounded by an N-type region 52 (corresponding to the semiconductor region according to claim 9) so that the semiconductor substrate 12 has a well structure. The well structure may be manufactured by forming an N + type impurity region in the semiconductor substrate 12 as an isolation. Also,
It may be manufactured by forming a P-type semiconductor substrate 12 in a part of an N-type semiconductor in a well shape.

FIG. 12 is a potential diagram for explaining the operation of the second embodiment. In the second embodiment,
As shown in FIG. 12, by applying a negative voltage of about −15 V to the terminal of the substrate potential of the semiconductor substrate 12, charge transfer from the charge storage unit 17 to the CCD diffusion layer 13 is realized. Charge transfer means). In such charge transfer, since the potential of the charge storage unit 17 is directly controlled, the charge transfer is ensured, and a large saturated charge amount of the charge storage unit 17 can be secured. Further, the semiconductor substrate 12 having the well structure has a small capacitance because of its small size. Therefore, the substrate potential of the semiconductor substrate 12 can be driven at a high speed with a small current, and the charge transfer operation can be further speeded up. Next, another embodiment will be described.

<< Third Embodiment >> A third embodiment is an embodiment of an exposure apparatus (including a positioning apparatus) according to the eleventh and twelfth aspects of the present invention. FIG. 13 is a diagram illustrating the exposure apparatus 60. In FIG. 13, a semiconductor wafer 62 is arranged on a wafer stage 61 as a substrate to be exposed. Above this semiconductor wafer 62,
A reticle 63a and a reticle stage 63b are arranged via a projection optical system of the exposure section 63. Through the projection optical system and the reticle 63a, so-called TTR (through-the-reticle) type imaging devices 64a and 64b are arranged at positions where the marks on the reticle 63a and the alignment marks on the wafer stage 61 side are imaged. You. In addition, so-called TTL (through-the-lens) type imaging devices 64c to 64d are arranged at positions where the alignment marks on the wafer stage 61 are imaged via the projection optical system. Further, off-axis type imaging devices 64e to 64f are arranged at positions where the alignment marks on the wafer stage 61 side are directly imaged without the intervention of the projection optical system. In addition, regarding the arrangement position of such an imaging device,
For example, it is known in JP-A-6-97031. Image information captured by these imaging devices 64a to 64f is provided to the position detection unit 65. This position detector 65
Performs position detection of the semiconductor wafer 62 and a reference mark plate (not shown) based on image information. The position control unit 66
The position of the wafer stage 61 is controlled based on the position detection result, and the semiconductor wafer 62 is positioned. The exposure section 63 projects a predetermined semiconductor circuit pattern via the reticle 63a onto the semiconductor wafer 62 thus positioned.

[0092] Such an exposure device 60 includes an image pickup device 64
The image pickup device according to any one of claims 1 to 9 is mounted as a to f. Therefore, it is easy to shorten the wavelength of illumination light for photographing, and it is possible to image a fine alignment mark with high image quality. As a result, the positioning accuracy of the exposure apparatus 60 can be further improved.

<< Fourth Embodiment >> In a fourth embodiment, the above-described imaging devices 11 and 51 (such as a CCD) are connected to the optical characteristics (in this example, the projection optical system PL (63)) of the test optical system. For example, the present invention is applied to measurement of wavefront aberration information such as coma, astigmatism, and spherical aberration. In the present embodiment, a case will be described in which aberration information of the projection optical system PL mounted on the exposure apparatus 70 is measured. However, the present invention is not limited to this, and may be mounted on various inspection apparatuses and measurement apparatuses. It is a matter of course that the imaging devices 11 and 51 may be used when measuring the optical characteristics of the optical system to be measured as the optical system to be tested.

Hereinafter, a fourth embodiment will be described with reference to FIG. FIG. 19 is a diagram showing an outline of the projection exposure apparatus 70. Exposure light generated from the light source 1 illuminates a reticle (mask) R via a mirror 9 and a condenser lens 10. Reticle R is mounted on reticle stage 10a, and reticle stage 10a is controlled by reticle stage control unit 6. A wafer holder 4 is provided on the wafer stage 3 (XY stage 3a, Z and leveling stage 3b), and a wafer W (not shown)
Are chucked on the wafer holder 4. The drive and position of the wafer stage 3 are controlled by the wafer stage controller 5. The main control unit 2 is electrically connected to the light source 1, the reticle stage control unit 6, and the wafer stage control unit 5, and is configured to control them collectively. The main control unit 2 includes a lens control unit LC (to be described later) for adjusting the projection optical system PL and an arithmetic processing unit PC (to be described later) that calculates the aberration of the optical system based on the measurement result by the aberration measurement unit UT described below. ) Are also electrically connected, and these are also collectively controlled.

An aberration measuring unit UT is detachably attached to the side surface of the wafer stage 3 via an attaching / detaching mechanism D. The aberration measurement unit UT has a collimator lens CL
, A two-dimensional lens array in which a plurality of lens elements L are two-dimensionally arranged, and a condensing position detection unit DET.
The image pickup device 1 described above is provided inside the light condensing position detection unit DET.
1 and 51 are provided, and the light flux that has passed through the plurality of lens elements L is condensed on the imaging surface IP of the imaging devices 11 and 51. When the aberration measurement unit UT is mechanically connected to the exposure device 70 (side surface of the stage 3) via the attachment / detachment mechanism D, the aberration unit UT is also electrically connected to the arithmetic processing unit PC. Then, communication becomes possible between the two (between the aberration measurement unit and the exposure apparatus).

In this embodiment, the arithmetic processing unit PC is provided on the exposure apparatus 70 side. However, the present invention is not limited to this. The arithmetic processing unit PC is provided in the aberration measurement unit UT, and the unit UT is connected to the exposure apparatus. Then, the configuration may be such that the arithmetic processing unit PC can communicate with the exposure apparatus.

Next, the procedure for measuring the wavefront aberration of the projection optical system (projection lens) PL will be described. Projection lens P
When measuring the wavefront of L, light having a wavefront of a spherical wave is incident on the projection lens PL as a light beam for measuring the wavefront aberration.
This spherical wave light is generated from the pinhole pattern PH by arranging a reticle R (FIG. 19) having a pinhole pattern PH at a position where the reticle is arranged, and illuminating the reticle R with light from the light source 1. Can be done. The present invention is not limited to this (pinhole pattern reticle), and a pinhole may be formed on the reticle stage 10a to illuminate it, or a point light source may be used. Alternatively, a region (a so-called lemon skin state) for diffusing and transmitting light from the light source 1 is provided on the reticle R or the reticle stage 10a, and the light transmitted through the lemon skin region is used as a light source for wavefront aberration measurement. It is good.

Reticle stage 10a and reticle R
However, it is desirable to have one of the pinhole and the lemon skin region described above. More preferably,
A plurality of pinholes having different sizes are provided, and it is desirable that the pinhole can be appropriately selected according to the purpose of measurement. When the light for wavefront aberration measurement is generated using the reticle R, the reticle R constitutes an aberration measurement optical system, and when the light is generated using the reticle stage 10a, the reticle stage 10a is used for measuring the aberration. This constitutes an optical system.

The projection lens PL is irradiated with the light of the spherical wave formed as described above. The wafer stage control unit 5 drives and controls the wafer stage 3 so that the transmitted wavefront from the projection lens PL is incident on the aberration measurement unit UT which is detachably provided on the side surface of the stage 3 via the attachment / detachment mechanism D. The light transmitted through the projection optical system PL is converted into parallel light by the collimator lens CL. And the minute lens L
Are two-dimensionally arranged.
If the test wavefront of the incident light has a deviation from the ideal wavefront, that is, the wavefront when the projection lens has no aberration, the deviation is reflected on the light-converging position detection unit DET by the ideal wavefront. The condensing position of the wavefront to be detected appears as a position shift with respect to the position. The arithmetic processing unit PC includes individual lenses L of a two-dimensional lens array.
The wavefront aberration of the projection lens PL is calculated based on the positional shift of the converging point.

As described above, at one point on the image plane formed by the projection lens PL, the displacement of each measurement point of the test wavefront with respect to each converging point of the ideal wavefront is measured, so that the aberration of the projection lens PL is obtained. , Spherical aberration and astigmatic difference can be obtained. Also, the unit UT is the projection lens PL
The stage 3 is driven by the stage control unit 5 so as to move to a plurality of points on the image forming plane. Then, at each of a plurality of points in the image plane of the projection lens PL, the position deviation of each measurement point of the test wavefront with respect to each of the converging points of the ideal wavefront is measured, and the aberration of the projection lens PL is calculated from the measurement results. Can be obtained as coma aberration, curvature of field, distortion, and astigmatism.

Then, the obtained wavefront aberration information such as coma, curvature of field, distortion, and astigmatism of the projection lens PL is fed back to the lens controller LC. The lens control unit LC adjusts the distance between the lens elements constituting the projection lens PL based on the wavefront aberration information and the pressure of the air at the distance to set the amount of aberration of the wavefront transmitted through the projection lens PL within a predetermined range. Keep within.

The unit UT may be detachably provided on the wafer holder 4 or the stage 3, may be incorporated in the stage 3, or may be provided near the stage 3. Further, by increasing the measurement resolution of the condensing position detection unit DET and the position control accuracy of the wafer stage 3, the aberration measurement accuracy of the projection lens PL can be improved. For example, when the detection resolution of the condensing position detection unit DET is 10 to 20 μm, 5
In a projection exposure apparatus that exposes an area of 5 mm × 5 mm, it is sufficient to control the wafer stage 13 at a pitch of 1 mm.

In the present embodiment, the wavefront aberration measuring device UT is configured to be detachable from the stage 3. However, as the attachment / detachment mechanism, a notch is provided in the stage 3, and the notch engages with the notch. The joint may be provided in the measuring device so as to be detachable. Further, when making the measuring device UT detachable from the stage 3, a part thereof, for example, the collimator lens CL and the lens L may be made detachable instead of the entire measuring device UT, and the detection unit DET may be fixed to the stage 3. . Conversely, for example, the collimator lens CL and the lens L may be fixed to the stage 3 and the detection unit DET may be detachable. Alternatively, all of the collimator lens CL, the lens L, and the detection unit DET may be fixed to the stage 3.

In the present embodiment, the wavefront aberration of the projection lens PL is measured in a state where the wavefront aberration is incorporated in the exposure apparatus. However, it may be measured before the projection lens PL is incorporated in the exposure apparatus. The timing of measuring the wavefront aberration may be any time of wafer exchange, every reticle exchange, or every predetermined time, or any other timing. The measurement accuracy at that time can be selected as described above. Further, in the present embodiment, an exposure light source is used as a light source for measuring aberration, but another light source may be used. As the exposure light source, g
Line (436 nm), i-line (365 nm), KrF excimer laser (248 nm), ArF excimer laser (19
3 nm), an F ₂ laser (157 nm), or a higher harmonic of a metal vapor laser or a YAG laser may be used.

<< Fifth Embodiment >> A fifth embodiment is a method for manufacturing the image pickup apparatus 11 according to the inventions of claims 13, 15, 16, and 19. FIG. 15 and FIG.
It is a figure showing a process of this manufacturing method. Hereinafter, each step of the present manufacturing method will be described with reference to FIGS.

First, a first alignment mark 102 is formed on the first surface side of the P + type substrate 30 having a concentration of about lE18 / cm ^3.
(Corresponding to the mark forming steps of claims 13, 15, and 16). This first alignment mark 102
A concave step is formed in silicon by etching or the like. The state so far is shown in FIG. The first alignment mark may have a convex shape. For example, a thick oxide film may be formed on the P + type substrate 30, and the oxide film may be partially removed to leave a convex step.

Note that the substrate 30 (silicon substrate) may be a high-concentration impurity substrate, and may be an N + type substrate. For example, as the N-type impurity of the substrate 30, Sb (antimony) is preferable. Further, the concentration of Sb is preferably 1E18 / cm ³ or more. Here, the reason why Sb is preferable is that the latter process (the P-type epitaxial layer 103)
This is because auto-doping can be suppressed in the vapor phase growth of This auto-doping greatly affects the shape of the first alignment mark 102 (history 104 described later). Depending on the conditions, the shape of the first alignment mark 102 (history 104) may be significantly distorted, and may not function as a mark. However, the above-mentioned Sb has a property that auto-doping hardly occurs. Therefore, by selecting Sb as an impurity of the substrate 30, the first alignment mark 102 (history 10
4) can be kept in a good shape.

[0108] Next, the first surface side of the P + -type substrate 30, a P-type epitaxial layer 103 at a concentration 1E15 / cm ³ to about 1
It is formed to a thickness of 0 μm (corresponding to the base forming steps of claims 13, 15, and 16). This P-type epitaxial layer 1
03 is the base portion of the device. At this time, a step of the first alignment mark 102 appears as a history 104 on the first surface side of the P-type epitaxial layer 103.
The re-marking is performed by using the history 104 as a position reference, and a re-marking mark 105 is newly formed on the first surface side of the P-type epitaxial layer 103 (corresponding to the re-marking step of claim 15). FIG. 15B shows the state up to this point.

Subsequently, on the first surface side of the P-type epitaxial layer 103, using the re-cut mark 105 as a position reference,
Channel separation, diffusion region, CCD diffusion layer 13, gate oxide film 14, transfer electrode 15, gate electrode for pixel reading,
A device structure such as an AL wiring, an AL pad (bonding pad) 20, and a passivation film is formed (corresponding to the first surface side processing step of claim 13 and the processing step of claim 15). The state so far is shown in FIG. 15c.

Next, the first surface side is SOG (Spin On Glas).
s) and flatten. If necessary, CMP (Chemical Me
The thickness is reduced by performing mechanical polishing or mechanical polishing. Thereafter, a low-concentration silicon substrate serving as the support substrate 21 is attached to the first surface with a silicon-based adhesive or the like. The state so far is shown in FIG. 16d. Here, hydrofluoric acid (50
%): Nitric acid: acetic acid in a solution of 1: 3: 8,
The + type substrate 30 is removed by etching. This kind of solution is
The P + type etching rate is faster than the P− type etching rate. The etching is stopped by utilizing the difference in the etching rates. At this time, a second alignment mark 111, which is a reversal mark of the first alignment mark, appears on the second surface side of the P-type epitaxial layer 103 (corresponding to the removing steps of claims 13 and 16). In order to reduce the etching time, the P + type substrate 30
May be thinned beforehand by polishing or the like. FIG. 16e shows the state up to this point.

Next, a device structure such as the charge storage section 17 is formed on the second surface side of the P-type epitaxial layer 103 with reference to the position of the second alignment mark 111, and the imaging device 11 shown in FIG. Is completed (corresponding to the second surface side processing step of claim 13 and the processing step of claim 16). By the way, in the state shown in FIG.
By forming a back processing layer, a pad opening, and the like using the alignment mark 111 as a position reference, a conventional back-illuminated imaging device as shown in FIG. 14 can also be formed.

As described above, in the manufacturing method of the fifth embodiment, the position reference of each surface (the re-strike mark 105,
Each of the second alignment marks 111) is formed based on the first alignment mark 102. Therefore, precise positional alignment between the two-sided structures becomes possible, and FIG.
It is possible to precisely position the charge accumulation portion 17, the CCD diffusion layer 13, the transfer electrode 15, the opening of the AL pad 20, and the like shown therein. As a result, the high-performance imaging device 1
1 can be manufactured. In addition, when the resolution of the imaging device 11 is increased (or miniaturized), the manufacturing yield is significantly improved.

In particular, in this manufacturing method, there is no step of forming a device structure on the other surface while performing alignment using the alignment mark on the opposite surface. Therefore, the imaging device 11 can be manufactured without using a conventional double-sided aligner or infrared aligner. Next, another embodiment will be described.

<< Sixth Embodiment >> A sixth embodiment is a method of manufacturing the imaging device 11 according to the invention. FIG. 17 is a diagram showing the steps of this manufacturing method. Hereinafter, the present manufacturing method will be described with reference to FIG. First, on the first surface side of the P + type substrate 30, the concentration 1E1
5 / cm ³ of P-type epitaxial layer 103 of about 10 μm
(Corresponding to the base forming step of claim 14).

During or after the step of forming the P-type epitaxial layer 103, the P-type epitaxial layer 103 is formed.
A high-concentration P + type region reaching the P + type substrate is formed in a part of the region by ion implantation, thermal diffusion, or the like to form a region 201 to be removed (corresponding to the step of forming a region to be removed according to claim 14). . A first alignment mark 202 is formed on the first surface side of the area 201 to be removed (corresponding to a mark forming step of claim 14). FIG. 17A shows the state up to this point.

Note that the region to be removed 201 may be a high-concentration impurity region, and may be an N + type region. In particular, in a case where the vapor phase growth of the P-type epitaxial layer 103 is continued after the formation of the first alignment mark 202,
It is preferable to select Sb (antimony) as the N-type impurity in the region 201 to be removed. In this case, Sb
Is preferably 1E18 / cm ³ or more. Here, Sb is preferable because the P-type epitaxial layer 1
This is because auto-doping can be suppressed in the vapor phase growth of 03. This auto-doping greatly affects the shape of the first alignment mark 202. Depending on conditions, the shape of the first alignment mark 202 may be significantly distorted, and may not function as a mark.
However, the above-mentioned Sb has a property that auto-doping hardly occurs. Therefore, the area to be removed 20
By selecting Sb as one impurity, the first alignment mark 202 can be kept in a good shape. As a result, a second alignment mark 203 to be described later
Can also be formed in a good shape.

The structure on the first surface side of the image pickup device 11 is formed with reference to the position of the first alignment mark 202 (corresponding to the first surface processing step of claim 14). In the above-described process, a layer sufficient to form a reversal mark is formed on the first alignment mark.
4). FIG. 17 shows the state up to this point.
b.

Next, the first surface side is flattened and the supporting substrate 2
Attach 1. In this state, the P + type substrate 30 and the region to be removed 201 are removed by etching. At this time, the second alignment mark 20, which is a reversal mark of the first alignment mark 202, is formed on the removal mark of the removal target area 201.
3 appears (corresponding to the removing step of claim 14). The state so far is shown in FIG. 17c.

Next, a device structure is formed on the second surface side of the P-type epitaxial layer 103 with reference to the position of the second alignment mark 203 to complete the imaging device 11 as shown in FIG. Corresponding to the second surface side processing step). By the way, in the state shown in FIG.
By forming a back processing layer, a pad opening, and the like using the alignment mark 203 as a position reference, it is also possible to form a conventional back-illuminated imaging device as shown in FIG.

As described above, in the manufacturing method of the sixth embodiment, the second alignment mark 203 on the second surface side is used.
Are formed so as to die-cut the first alignment mark 202 on the first surface side. Therefore, since the two alignment marks are precisely aligned, it is possible to precisely align the charge accumulation portion 17, the CCD diffusion layer 13, the transfer electrode 15, the opening of the AL pad 20, and the like shown in FIG. . As a result, it is possible to manufacture the high-performance imaging device 11. In addition, when the resolution of the imaging device 11 is increased (or miniaturized), the manufacturing yield is significantly improved.

In particular, in this manufacturing method, there is no step of forming a device structure on the other surface while performing alignment using the alignment mark on the opposite surface. Therefore, the imaging device 11 can be manufactured without using a conventional double-sided aligner or infrared aligner. Next, another embodiment will be described.

<< Seventh Embodiment >> A seventh embodiment is a method of manufacturing the imaging device 11 according to the eighteenth aspect. FIG. 18 is a diagram showing the steps of this manufacturing method. First, the P-type epitaxial layer 103 is formed on the first surface side of the P + -type substrate 30 (corresponding to the base forming step of claim 18).

Next, the first of the P-type epitaxial layers 103
By performing ion implantation, thermal diffusion, or the like from the surface side, a high-concentration P + type region reaching the P + type substrate is formed in the planned opening of the AL pad 20 or the like. This P + type region becomes the planned opening region 301 (corresponding to the step of forming a planned opening region of claim 18). FIG. 18A shows the state up to this point. After the structure on the first surface side is formed, the first
The surface side is flattened, and the support substrate 21 is attached. The state so far is shown in FIG.

Next, the P + type substrate 30 and the planned opening area 301 are removed by etching. At this time, a pad opening 302 or the like appears as a removal mark of the opening scheduled area 301. (Corresponding to the removing step of claim 18). The state so far is shown in FIG. 17c. Next, a structure is formed on the second surface side to complete the imaging device 11 as shown in FIG. 2. As described above, in the manufacturing method of the seventh embodiment, the planned opening portion on the second surface side Are positioned from the first surface side. Therefore, it is possible to form an opening on the second surface side that is aligned with the structure on the first surface side (for example, the AL pad 20).

<< Supplementary Information of the Embodiment >> In the above-described embodiment, at the start of charge accumulation, the vertical transfer unit 16 (ineffective charge discharging means) uses unnecessary charges in the charge accumulation unit 17 (before the exposure time). The accumulated afterimage and dark current) may be wiped out via the CCD diffusion layer 13. By such an operation, it is possible to further improve the imaging quality. Further, by adjusting the length of the accumulation time in this way, it is also possible to realize an electronic shutter function.

In the above-described embodiment, the transfer electrode 1
Although the overflow of the charge storage unit 17 is adjusted by the voltage adjustment of No. 5, the present invention is not limited to this. For example, the impurity concentration of the semiconductor substrate 12 may be adjusted so that the excess charge that has overflowed the charge storage section 17 flows toward the CCD diffusion layer 13 before passing over the channel stop 17a.

Further, in the above-described embodiment, both the transfer electrode 15 and the substrate potential are controlled to
7 may be transferred to the CCD diffusion layer 13. By such an operation, it is possible to reliably transfer charges to the charge storage section 17 having a large saturated charge amount. Further, in the above-described embodiment, the support substrate 21 is provided on the semiconductor substrate.
Then, the whole surface is chemically etched, but the present invention is not limited to this. For example, a chip peripheral portion may be left during etching. In this case, it is possible to further increase the mechanical strength of the chip.

In the above-described embodiment, the semiconductor substrate is thinned by chemical etching. However, the present invention is not limited to this. For example, thinning may be performed by a method such as mechanical polishing or anisotropic etching. Further, in the embodiment described above, the P type is the first conductivity type, and the N type is
The type is the second conductivity type, but is not limited to this. The N-type may be the first conductivity type and the P-type may be the second conductivity type.

As an exposure apparatus according to the third or fourth embodiment, a scanning exposure apparatus (US Pat. No. 5,473,973) for exposing a reticle pattern by synchronously moving a reticle and a substrate.
410) can also be applied. The exposure apparatus according to the third embodiment can be applied to a step-and-repeat exposure apparatus that exposes a reticle pattern while the reticle and the substrate are stationary and sequentially moves the substrate. .

Incidentally, as the exposure apparatus of the third embodiment,
The present invention can also be applied to a proximity exposure apparatus that exposes a reticle pattern by bringing a reticle and a substrate into close contact without using a projection optical system. Further, the application of the exposure apparatus is not limited to an exposure apparatus for manufacturing a semiconductor. For example, an exposure apparatus for a liquid crystal that exposes a liquid crystal display element pattern to a square glass plate, or a thin film magnetic head is manufactured. Widely applicable to the exposure apparatus.

The light source of the exposure apparatus according to the third embodiment includes g-line (436 nm), i-line (365 nm), KrF
Not only an excimer laser (248 nm), an ArF excimer laser (193 nm), and an F ₂ laser (157 nm) but also a charged particle beam such as an X-ray or an electron beam can be used. For example, when an electron beam is used, a thermionic emission type lanthanum hexaborite (LaB ₆ ) or tantalum (Ta) can be used as an electron gun.

The magnification of the projection optical system may be not only a reduction system but also an equal magnification or an enlargement system. As the projection optical system, using a material which transmits far ultraviolet rays such as quartz and fluorite as the glass material when using a far ultraviolet rays such as an excimer laser, when using the F ₂ laser or X-ray catadioptric or refractive The optical system may be a reflection type reticle. In the case where an electron beam is used, an electron optical system including an electron lens and a deflector may be used as the optical system. It goes without saying that the optical path through which the electron beam passes is in a vacuum state.

Further, a linear motor (US Pat. No. 5,623,853 or US Pat.
528118), either an air levitation type using an air bearing or a magnetic levitation type using Lorentz force or reactance force may be used. The stage may be of a type that moves along a guide or a guideless type that does not have a guide.

As the stage driving device, a planar motor that drives a stage by electromagnetic force with a magnet unit having two-dimensionally arranged magnets and an armature unit having two-dimensionally arranged coils opposed to each other may be used. Good. in this case,
One of the magnet unit and the armature unit may be connected to the stage, and the other of the magnet unit and the armature unit may be provided on the moving surface side of the stage.

The reaction force generated by the movement of the wafer stage is disclosed in Japanese Patent Application Laid-Open No. 8-166475 (US Pat.
28118), a frame member may be used to mechanically escape to the floor (ground). Note that the reaction force generated by the movement of the reticle stage is disclosed in
As described in US Pat. No. 3,330,224 (US S / N 08/416558), a frame member may be used to mechanically escape to the floor (ground).

Further, an illumination optical system and a projection optical system composed of a plurality of lenses are incorporated in the main body of the exposure apparatus, and optical adjustment is performed. The exposure apparatus of the present embodiment can be manufactured by connecting wires and pipes and performing overall adjustment (electrical adjustment, operation confirmation, and the like). It is desirable that the manufacture of the exposure apparatus be performed in a clean room in which the temperature, cleanliness, and the like are controlled.

In the case of a microdevice such as a semiconductor device, a step of designing the function and performance of the device, a step of producing a reticle based on the design step, a step of producing a wafer from a silicon material, It is manufactured through a step of exposing a reticle pattern on a wafer by an apparatus, a step of assembling a device (including a dicing step, a bonding step, and a package step), an inspection step, and the like.

Further, the imaging apparatus of the present invention is not limited to the use of the exposure apparatus, but is applicable to all systems including the imaging apparatus. In the fifth to seventh embodiments, the case where the imaging device 11 is manufactured has been described. However, the device manufacturing method of the present invention is not limited to manufacturing the imaging device 11. The device manufacturing method of the present invention is applicable to a general device manufacturing method. For example, the present invention is applicable to liquid crystal display devices and semiconductor devices in general. In particular, the device manufacturing method of the present invention is suitable for an application in which a device structure is formed on both sides due to the above-described effects.

[0139]

As described above, in the image pickup apparatus according to the present invention, the moving distance of the signal charges on the second surface side is substantially reduced by forming the charge accumulation portion on the second surface side. . By such an action of shortening the moving distance, it is possible to improve the energy beam detection efficiency and the generation of smear. Further, in the imaging device according to the present invention, since the signal charge is blocked by the charge storage unit, it is possible to omit the mechanical shutter which is conventionally required. In particular, according to the first aspect of the present invention, since the depletion preventing layer is provided, it is possible to reliably suppress the mixing of dark current from the second surface side.

According to the second aspect of the present invention, since the depletion preventing layer is set to the first conductivity type, it is possible to crush the backside well and to further improve the efficiency of detecting energy rays.

According to the third aspect of the present invention, since the depletion preventing layer is set to have an impurity distribution that can transmit the energy beam to be detected, the efficiency of detecting the energy beam can be improved.

According to the fourth aspect of the present invention, the charge storage portion is completely depleted when the charge transfer is completed. This complete depletion can significantly reduce the afterimage. Note that the above-described depletion prevention layer has an effect of facilitating realization of the complete depletion.

According to the fifth aspect of the present invention, while the charge accumulating portion is accumulating the signal charges, the ineffective charges of the charge transfer portion are discharged. Therefore, the dark current generated on the first surface side is reduced by the electric charges. It is possible to capture a good image without the possibility of staying in the transfer unit.

In the present invention, a potential operation is performed such that the potential on the first surface side of the charge transfer section approaches the substrate potential. As a result, surface depletion on the first surface side is avoided, and a good image in which dark current on the first surface side is suppressed can be captured.

According to the seventh aspect of the present invention, excess charges overflowing from the charge storage section are discharged through the charge transfer section. Therefore, there is little possibility that the excess charge overflows to the charge storage portion of the adjacent pixel, and the blooming phenomenon can be reliably suppressed.

According to the eighth aspect of the present invention, the signal charge is transferred from the charge storage section to the charge transfer section by controlling the substrate potential of the semiconductor substrate. As a result, the transfer of the signal charge becomes reliable and easy, and the saturated charge amount of the charge storage portion can be further secured.

According to the ninth aspect of the present invention, since the semiconductor substrate has a well structure, the capacitance of the semiconductor substrate is small, and the potential of the semiconductor substrate can be controlled at high speed. Therefore, the speed of the charge transfer operation from the charge storage unit to the charge transfer unit can be further increased.

According to the manufacturing method of the tenth aspect, it is possible to manufacture the imaging device of the first aspect.

In the positioning device according to the eleventh aspect,
Since the above-described imaging apparatus according to the first to ninth aspects is used, it is possible to improve imaging quality and obtain high positioning accuracy.

In the exposure apparatus according to the twelfth aspect, since the positioning apparatus according to the eleventh aspect is mounted, it is possible to improve the exposure position accuracy of the substrate.

In the device manufacturing method according to the thirteenth aspect, the device structure on the first surface side is formed using the history of the first alignment mark as a position reference. Further, a device structure on the second surface side is formed using the inversion mark (second alignment mark) of the first alignment mark as a position reference. Therefore, it is possible to reliably and easily form a device structure that is aligned on both the first surface side and the second surface side of the base portion. In addition, since the alignment of the two-sided structure can be naturally achieved in the process of manufacturing one side at a time, the conventional double-sided aligner and infrared aligner become unnecessary. Therefore, it is possible to manufacture a device that requires alignment of the double-sided structure using a general manufacturing apparatus.

According to a fourteenth aspect of the device manufacturing method, the first alignment mark is used as a position reference and the first
The device structure on the surface side is formed. A reversal mark of the first alignment mark (second alignment mark)
Is used as a position reference to form a device structure on the second surface side. Therefore, it is possible to reliably and easily form a device structure that is aligned on both the first surface side and the second surface side of the base portion. In addition, since the alignment of the two-sided structure can be naturally achieved in the process of manufacturing one side at a time, the conventional double-sided aligner and infrared aligner become unnecessary. Therefore, it is possible to manufacture a device that requires alignment of the double-sided structure using a general manufacturing apparatus.

In the device manufacturing method according to the fifteenth aspect, a base portion of the device is formed on the first alignment mark of the substrate, and a history is generated in the base portion. By using the reworked mark of this history as a reference for the position,
It is possible to form a device structure that is aligned with the first alignment mark on the substrate on the first surface side of the base portion.

In the device manufacturing method according to the sixteenth aspect, a base portion of the device is formed on the first alignment mark of the substrate, and thereafter, the substrate is removed. as a result,
A second alignment mark, which is a reversal mark of the first alignment mark, appears on the base portion. By using this second alignment mark as a position reference, the first alignment mark
It is possible to form a device structure that is aligned with the alignment mark on the second surface side of the base portion.

In the device manufacturing method according to the seventeenth aspect, the region to be removed is formed in a pattern at the time of processing the first surface side of the base portion. By removing the area to be removed from the second surface side, an alignment mark appears on the second surface side of the base portion. Therefore, it is not necessary to newly form an alignment mark when shifting the manufacturing process from the first surface side to the second surface side. Also, by using this alignment mark as a reference for the position, it is possible to form a device structure on the second surface side of the base portion that is aligned with the processing on the first surface side.

In the device manufacturing method according to the eighteenth aspect, when the base portion is processed on the first surface side, an expected opening area is formed at the expected opening portion on the second surface side. By removing the opening area from the second surface side, an opening hole is formed on the second surface side of the base portion. Since the opening hole is buried in advance from the first surface side as an expected opening region, it is possible to easily align the device structure on the first surface side with the opening hole.

In the device manufacturing method according to the nineteenth aspect, a substrate containing antimony is used. Therefore, the auto-doping of the substrate in the base forming process is suppressed,
It is possible to favorably form or maintain the shape of the alignment mark. As a result, a device structure can be manufactured with high positional accuracy.

In the device manufacturing method according to the twentieth aspect, the region to be removed containing antimony is formed. Therefore, it is possible to suppress the auto doping of the region to be removed in the base forming step, and to form or maintain the shape of the alignment mark satisfactorily. As a result, a device structure can be manufactured with high positional accuracy.

In the wavefront aberration measuring apparatus according to the twenty-first aspect, since the above-described imaging apparatus according to the first to ninth aspects is used, the imaging quality is improved, and high measurement accuracy of the wavefront aberration is obtained. Becomes possible.

In the exposure apparatus according to the twenty-second aspect, the wavefront aberration measuring apparatus according to the twenty-first aspect is mounted, so that the wavefront aberration of the projection optical system or the like can be detected with high accuracy.

[Brief description of the drawings]

FIG. 1 is a view of an imaging device 11 according to a first embodiment as viewed from a second surface side.

FIG. 2 is a sectional view taken along line AA ′ of the imaging device 11.

FIG. 3 is a diagram illustrating a first method of manufacturing the imaging device 11.

FIG. 4 is a diagram illustrating a first manufacturing method of the imaging device 11.

FIG. 5 is a diagram illustrating a second method of manufacturing the imaging device 11.

FIG. 6 is a diagram illustrating a second method of manufacturing the imaging device 11.

FIG. 7 is a diagram illustrating a charge storage operation and a charge transfer operation.

FIG. 8 is a diagram illustrating a dark current suppression operation on the first surface side.

FIG. 9 is a diagram illustrating an operation of discharging excess charges.

FIG. 10 is a diagram illustrating a charge reading operation.

FIG. 11 is a sectional view of an imaging device 51 according to a second embodiment.

FIG. 12 is a diagram illustrating a charge transfer operation according to the second embodiment.

FIG. 13 is a view showing an exposure apparatus 60.

FIG. 14 is a diagram showing a conventional example of a back-illuminated imaging device 71.

FIG. 15 is a view (1/1/2) showing a manufacturing process of the fifth embodiment;
2).

FIG. 16 is a view showing a manufacturing process of the fifth embodiment (2 /
2). .

FIG. 17 is a diagram illustrating a manufacturing process according to the sixth embodiment;

FIG. 18 is a diagram illustrating a manufacturing process according to the seventh embodiment.

FIG. 19 is a diagram illustrating an apparatus configuration according to a fourth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 Image pickup device 12 Semiconductor base 13 CCD diffusion layer 14 Gate oxide film 15 Transfer electrode 16 Vertical transfer part 17 Charge accumulation part 18 Depletion prevention layer 19 Antireflection film 20 AL pad 30, 40 P + type substrate 31, 32, 41, 43 , 103 P-type epitaxial layer 42 P + -type impurity region 52 N-type region 60 Exposure device 61 Wafer stage 62 Semiconductor wafer 63 Exposure unit (projection optical system PL) 65 Position detection unit 102, 202 First alignment mark 104 First alignment mark 102 History of unevenness 105 of reworked reworked marks 111, 203 second alignment mark 201 area to be removed 301 area to be opened 302 pad opening

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H01L 21/027 H04N 5/335 U 27/14 H01L 27/14 B H04N 5/335 21/30 502M 516A 525N 27/14 ZF term (for reference) 2G088 EE01 EE30 FF02 FF10 FF14 GG21 JJ05 JJ09 JJ37 LL12 LL15 4M118 AA05 AB01 BA12 DA03 EA01 FA06 FA21 FA26 FA32 FA38 GA02 GA10 HA30 5C024 AX01 AX11 AX16 CX12 CX12 CX12 CXA CX12 CXA CX12 CXA CX12 CX12 A DA13 DA27 DB01 DC12 EA12 EA13 EA15 EA16 EA17 EA22 EA23 EB01

Claims (22)

[Claims] 1. A semiconductor substrate of a first conductivity type, and a signal generated by an energy beam formed on a first surface side of the semiconductor substrate and irradiated from a second surface side opposite to the first surface side. A back-illuminated imaging device having a charge transfer unit for transferring and reading out a charge, a plurality of charge transfer units being formed on the second surface side facing the charge transfer unit on the first surface side, and A charge accumulation unit of a second conductivity type different from the first conductivity type, which accumulates generated signal charges in pixel units; and a charge accumulation unit provided on the second surface side of the charge accumulation unit, around the charge accumulation unit. A depletion prevention layer for preventing the expanding depletion region from reaching the second surface; and charge transfer means for transferring the signal charges stored in the charge storage unit to the charge transfer unit. Imaging device. 2. The imaging device according to claim 1, wherein the depletion prevention layer is a layer of the first conductivity type. 3. The imaging device according to claim 1, wherein the depletion prevention layer has an impurity distribution through which the energy rays can pass, and the depletion region reaches the second surface. An image pickup device having an impurity concentration capable of preventing the occurrence of the image. 4. The imaging device according to claim 1, wherein the charge storage unit is completely depleted when the charge transfer is completed. 5. A signal generated by a semiconductor substrate of a first conductivity type and an energy beam formed on a first surface side of the semiconductor substrate and irradiated from a second surface side opposite to the first surface side. A back-illuminated imaging device having a charge transfer unit for transferring and reading out a charge, a plurality of charge transfer units being formed on the second surface side facing the charge transfer unit on the first surface side, and A charge accumulation unit of a second conductivity type different from the first conductivity type for accumulating the generated signal charges in pixel units, and a charge transfer unit for transferring the signal charges accumulated in the charge accumulation unit to the charge transfer unit An image capturing apparatus comprising: an invalid charge discharging unit that drives the charge transfer unit to discharge invalid charges during a period in which the charge storage unit stores signal charges. 6. A signal generated by a semiconductor substrate of a first conductivity type and an energy beam formed on a first surface side of the semiconductor substrate and irradiated from a second surface side opposite to the first surface side. A back-illuminated imaging device having a charge transfer unit for transferring and reading out a charge, a plurality of charge transfer units being formed on the second surface side facing the charge transfer unit on the first surface side, and A charge accumulation unit of a second conductivity type different from the first conductivity type for accumulating the generated signal charges in pixel units, and a charge transfer unit for transferring the signal charges accumulated in the charge accumulation unit to the charge transfer unit For at least a predetermined period during the signal charge accumulation period by the charge accumulation unit, the potential of the charge transfer unit on the first surface side is brought close to the substrate potential, and the inflow of dark current from the first surface side is reduced. Dark current suppression Imaging apparatus characterized by comprising a. 7. A signal generated by a semiconductor substrate of a first conductivity type and an energy beam formed on a first surface side of the semiconductor substrate and irradiated from a second surface side opposite to the first surface side. A back-illuminated imaging device having a charge transfer unit for transferring and reading out a charge, a plurality of charge transfer units being formed on the second surface side facing the charge transfer unit on the first surface side, and A charge accumulation unit of a second conductivity type different from the first conductivity type for accumulating the generated signal charges in pixel units, and a charge transfer unit for transferring the signal charges accumulated in the charge accumulation unit to the charge transfer unit And an excess charge discharging means for overflowing excess charge generated in excess of the saturated charge amount of the charge storage unit to the charge transfer unit, driving the charge transfer unit and discharging the excess charge. Featured imaging Location. 8. A signal generated by a semiconductor substrate of a first conductivity type and an energy beam formed on a first surface side of the semiconductor substrate and irradiated from a second surface side opposite to the first surface side. A back-illuminated imaging device having a charge transfer unit for transferring and reading out a charge, a plurality of charge transfer units being formed on the second surface side facing the charge transfer unit on the first surface side, and A charge accumulation unit of a second conductivity type different from the first conductivity type for accumulating the generated signal charges in pixel units, and a charge transfer unit for transferring the signal charges accumulated in the charge accumulation unit to the charge transfer unit The charge transfer unit controls the potential of the charge storage unit by applying a voltage to the semiconductor substrate,
An imaging device, which is means for transferring the electric charge of the electric charge storage unit to the electric charge transfer unit. 9. The imaging device according to claim 8, wherein the semiconductor base has a well structure surrounded by the semiconductor region of the second conductivity type. 10. A method for manufacturing a back-illuminated imaging device, comprising: a thinning step of thinning a semiconductor substrate of a first conductivity type; and one surface side of the thinned semiconductor substrate. The first
An accumulating portion forming step of forming a plurality of charge accumulating portions of a second conductivity type different from the conductivity type; and preventing the surface depletion by the charge accumulating portions on the one surface side of the thinned semiconductor substrate. The first of
Forming a conductive type depletion preventing layer. 11. The method according to claim 1, wherein
An image capturing apparatus according to claim 1, an image capturing apparatus that captures an object or a mark formed on the object using the image capturing apparatus, and detects position information of the object based on a captured image. A position control unit for positioning the object based on the information. 12. An exposure apparatus comprising: the alignment apparatus according to claim 11; and an exposure unit configured to expose a predetermined pattern to a substrate, which is an object aligned by the alignment apparatus. . 13. A mark forming step of forming a first alignment mark on a first surface side of a substrate; a base forming step of forming a base portion of a device on the first surface side of the substrate; A first surface side processing step of forming a first structure on the first surface side of the base portion with reference to a concave or convex on the first surface side of the base portion formed in the forming step; A removing step of removing the substrate from a second surface side of the base portion opposite to the first surface side; and a second alignment appearing on the second surface side of the base portion in the removing step. A second surface side processing step of forming a second structure different from the first structure on the second surface side of the base portion with reference to a mark. 14. A pedestal forming step of forming a pedestal portion of a device on the first surface side of the substrate, and forming a to-be-removed region which reaches the substrate and can be selectively removed in the pedestal portion. A step of forming an area to be removed; a mark forming step of forming a first alignment mark on the first surface side of the area to be removed; and a step of forming a first alignment mark on the first surface side of the base portion with reference to the first alignment mark. A first surface side processing step of forming a first structure, a layer forming step of forming a layer so as to cover at least the first alignment mark, and an opposite side of the base portion to the first surface side. A removing step of removing the substrate and the area to be removed from the second surface side; and a second alignment mark appearing on the second surface side in the removing step as a reference. , The first structure A second surface side processing step of forming a second structure different from the first structure. 15. A mark forming step of forming a first alignment mark on a first surface side of a substrate; a base forming step of forming a base portion of a device on the first surface side of the substrate; In the forming step, the first portion of the base portion is defined on the basis of the recess or protrusion on the first surface side of the base portion caused by the recess or protrusion of the first alignment mark.
Forming a second alignment mark on a surface side; and a processing step of forming a predetermined structure on the first surface side of the base portion with reference to the second alignment mark. Device manufacturing method. 16. A mark forming step of forming a concave or convex first alignment mark on a first surface side of a substrate, and a base forming step of forming a device base portion on the first surface side of the substrate. Removing the substrate from a second surface side of the base portion opposite to the first surface side, so that a second alignment mark appears on the second surface side of the base portion; A process of forming a predetermined structure on the second surface side of the base with reference to the second alignment mark. 17. A pedestal forming step of forming a pedestal portion of a device on a first surface side of a substrate on which a first alignment mark is formed; and selectively arriving at the pedestal portion to reach the substrate. Forming a layer to be removed to form a layer to be removed, and forming a layer so as to cover at least the first alignment mark; and a side opposite to the first surface of the base portion. Removing the substrate and the area to be removed from the second surface side of the base plate, and causing a second alignment mark to appear on the second surface side of the base portion; and removing the base with reference to the second alignment mark. A process of forming a predetermined structure on the second surface side of the base portion. 18. A base forming step of forming a base portion of the device on the first surface side of the substrate; and during or after the base forming step, reaching the substrate at an expected opening of the base portion; Forming a scheduled opening region that can be selectively removed, and removing the substrate and the scheduled opening region from a second surface of the base portion opposite to the first surface. A removing step of forming an opening hole (removal mark of the planned opening area) on the second surface side of the base portion. 19. The method of claim 13, claim 15, or claim 16.
18. The device manufacturing method according to claim 17, wherein the substrate contains antimony (Sb). 20. The device manufacturing method according to claim 14, wherein in the step of forming a region to be removed, the region to be removed is formed using a material containing antimony (Sb). A device manufacturing method characterized by the above-mentioned. 21. Any one of claims 1 to 9
Item; an aberration measurement optical system that emits a light beam for aberration measurement to a test optical system; and the light beam that has passed through the test optical system is condensed on an imaging surface of the image pickup device. A condensing lens, a position detection unit that detects position information of the light beam condensed on the imaging surface, and a calculation unit that calculates aberration of the test optical system based on a detection result by the position detection unit. An aberration measuring device, characterized in that: 22. An exposure apparatus, comprising: the aberration measurement apparatus according to claim 21; and a projection optical system to be subjected to aberration measurement by the aberration measurement apparatus.