JP2010098013A - Bonding evaluation gauge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bonding evaluation method for quickly evaluating the accuracy of substrate positioning. <P>SOLUTION: The bonding evaluation method for evaluating bonding accuracy when bonding a pair of substrates includes: a bonding stage of bonding the pair of substrates holding an evaluation pattern layer having repetitive patterns repeated in a fixed cycle therebetween; and a polarized light measuring stage of irradiating the evaluation pattern layer with polarized light transmitted through one of the pair of substrates and measuring the change of the polarization state of light emitted from the evaluation pattern layer. In the measuring stage, the polarized light is linearly polarized light for instance, and the polarization state can be measured by the intensity of a polarized light vertical component which is a polarization component orthogonal to the polarization plane of the linearly polarized light in the light emitted from the evaluation pattern layer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an evaluation gauge, and more particularly to a bonding evaluation method, a stacked semiconductor device, a bonding evaluation apparatus, and a substrate bonding apparatus using the evaluation gauge.

Patent Document 1 describes that a stacked semiconductor device is manufactured by stacking wafers on which elements are formed.
JP 2007-103225 A

  Then, in order to solve the above-mentioned problem, as a first aspect of the present invention, there is provided a bonding evaluation method for evaluating bonding accuracy when bonding a pair of substrates, and an evaluation pattern layer having a repeated pattern repeated at a constant cycle A step of bonding a pair of substrates across the substrate, and a polarization measuring step of irradiating the evaluation pattern layer with polarized light transmitted through one of the pair of substrates and measuring a change in the polarization state of the light emitted from the evaluation pattern layer; A bonding evaluation method is provided.

  Further, as a second aspect of the present invention, a substrate holding unit that holds a bonded substrate including an evaluation pattern layer having a repeated pattern that repeats at a constant period, and a pair of substrates bonded with the evaluation pattern layer interposed therebetween, A polarization illumination unit that irradiates the evaluation pattern layer of the bonded substrate held by the holding unit with polarized light that passes through one of the pair of substrates, and a polarization measurement unit that measures a change in the polarization state of the light emitted from the evaluation pattern layer Is provided.

  Furthermore, as a third aspect of the present invention, the bonding evaluation apparatus, a bonding apparatus that aligns and bonds one of the pair of substrates to the other, and the pair of substrates bonded by the bonding apparatus are heated and heated. There is provided a substrate laminating apparatus comprising a heating and pressing apparatus for pressing and bonding.

  Furthermore, as a fourth aspect of the present invention, a bonding evaluation gauge for evaluating the bonding accuracy of a pair of substrates, which is bonded with an evaluation pattern layer sandwiched between an evaluation pattern layer having a repeated pattern repeated at a constant cycle. A bonding evaluation gauge is provided that has a pair of substrates and changes the polarization state of the emitted light emitted from the evaluation pattern layer when the evaluation pattern layer is irradiated with polarized light that passes through one of the pair of substrates. The

  Furthermore, as a fifth aspect of the present invention, there is provided an evaluation pattern layer having a repeated pattern repeated at a constant period and a pair of substrates at least one of which is a semiconductor substrate and sandwiched with the evaluation pattern layer interposed therebetween. Thus, there is provided a stacked semiconductor device in which the polarization state of polarized light emitted from the evaluation pattern changes when the evaluation pattern layer is irradiated with polarized light that has passed through one of the pair of substrates.

  The above summary of the present invention is not an exhaustive list of all features of the invention. Further, a sub-combination of these feature groups can be an invention.

  Hereinafter, the present invention will be described through embodiments of the invention. The embodiments described below do not limit the invention according to the claims. In addition, not all combinations of features described in the embodiments are essential for the solution of the invention.

  FIG. 1 is a plan view schematically showing the overall structure of the bonding apparatus 100. The bonding apparatus 100 includes a normal temperature part 102 and a high temperature part 202 formed inside a common casing 101.

  The normal temperature unit 102 has a plurality of substrate cassettes 111, 112, 113 and a control panel 120 facing the outside of the housing 101. The control panel 120 includes a control unit that controls the operation of the entire bonding apparatus 100. In addition, the control panel 120 has an operation unit that is operated by a user from the outside when the joining apparatus 100 is turned on, various settings, and the like. Further, the control panel 120 may include a connection unit that connects the other devices provided to the bonding apparatus 100.

  The substrate cassettes 111, 112, and 113 accommodate the substrates 180 bonded in the bonding apparatus 100 or the substrates 180 bonded in the bonding apparatus 100. The substrate cassettes 111, 112, and 113 are detachably attached to the housing 101. As a result, a plurality of substrates 180 can be loaded into the bonding apparatus 100 at once. Further, the substrates 180 bonded in the bonding apparatus 100 can be collected at a time.

  The substrate 180 loaded in the bonding apparatus 100 may be a single silicon wafer, compound semiconductor wafer, glass substrate, or the like, in which elements, circuits, terminals, and the like are formed. In addition, the loaded substrate 180 may be a laminated substrate that is already formed by laminating a plurality of wafers.

  The room temperature unit 102 includes a pre-aligner 130, an aligner 140, a holder stocker 150, an evaluation unit 160, and a pair of robot arms 171 and 172, which are arranged inside the housing 101. When the substrate is loaded on the aligner 140, the pre-aligner 130 provisionally aligns the positions of the individual substrates 180 so that each substrate 180 is loaded in a narrow adjustment range of the aligner 140 because of high accuracy. Thereby, the positioning of the substrate 180 in the aligner 140 is completed quickly and reliably.

  The aligner 140 includes an upper stage 141, a lower stage 142, and an interferometer 144. The upper stage 141 and the lower stage 142 carry the substrate 180 alone or the substrate holder 190 holding the substrate 180.

  In addition, a heat insulating wall 145 and a shutter 146 are disposed around the aligner 140. The space surrounded by the heat insulating wall 145 and the shutter 146 communicates with an air conditioner or the like and is precisely temperature-controlled, so that the alignment accuracy in the aligner 140 is maintained. The holder stocker 150 accommodates a plurality of substrate holders 190 and makes them stand by.

  Of the pair of robot arms 171 and 172, the robot arm 171 disposed on the side closer to the substrate cassettes 111, 112, and 113 transports the substrate 180 between the substrate cassettes 111, 112, 113, the pre-aligner 130, and the aligner 140. . The robot arm 172 disposed on the side far from the substrate cassettes 111, 112, 113 conveys the substrate 180 and the substrate holder 190 between the aligner 140, the evaluation unit 160 and the air lock 220. The robot arm 172 is also responsible for loading and unloading the substrate holder 190 with respect to the holder stocker 150.

  Further, the robot arm 172 has a function of turning over one of the substrates 180 to be joined. Note that the robot arms 171, 172, 230 adsorb and hold the substrate holder 190 by vacuum adsorption, electrostatic adsorption, or the like. Further, the substrate holder 190 attracts and holds the substrate 180 by, for example, electrostatic attraction. The structure and operation of the evaluation unit 160 will be described later separately.

  The high temperature unit 202 includes a heat insulating wall 210, an air lock 220, a robot arm 230, and a plurality of heating and pressing units 240. The heat insulating wall 210 surrounds the high temperature part 202 to maintain a high internal temperature of the high temperature part 202 and blocks heat radiation from the high temperature part 202 to the outside. Thereby, the influence which the heat of the high temperature part 202 has on the normal temperature part 102 can be suppressed.

  The robot arm 230 conveys the substrate 180 and the substrate holder 190 between any one of the heating and pressing units 240 and the air lock 220. The air lock 220 includes shutters 222 and 224 that open and close alternately on the normal temperature part 102 side and the high temperature part 202 side.

  When the substrate 180 and the substrate holder 190 are carried into the high temperature unit 202 from the normal temperature unit 102, first, the shutter 222 on the normal temperature unit 102 side is opened, and the robot arm 172 carries the substrate 180 and the substrate holder 190 into the air lock 220. . Next, the shutter 222 on the normal temperature part 102 side is closed, and the shutter 224 on the high temperature part 202 side is opened.

  Subsequently, the robot arm 230 unloads the substrate 180 and the substrate holder 190 from the air lock 220 and inserts them into one of the heating and pressing units 240. The heating / pressurizing unit 240 pressurizes the substrate 180 carried into the heating / pressurizing unit 240 while being sandwiched between the substrate holders 190. Thereby, the substrate 180 is permanently bonded.

  When the substrate 180 and the substrate holder 190 are carried out from the high temperature unit 202 to the normal temperature unit 102, the above series of operations are executed in reverse order. Through a series of these operations, the substrate 180 and the substrate holder 190 can be carried into or out of the high temperature part 202 without leaking the internal atmosphere of the high temperature part 202 to the normal temperature part 102 side.

  FIG. 2A to FIG. 2E are diagrams showing the transition of the state of the substrate 180 and the substrate holder 190 in the bonding apparatus 100 for bonding two substrates. Hereinafter, the operation of the bonding apparatus 100 will be described with reference to FIGS. 2a to 2e.

  As shown in FIG. 2a, at the beginning of the operation of the bonding apparatus 100, each of the substrates 180 to be bonded is individually accommodated. The substrate holder 190 is also individually accommodated in, for example, a holder stocker. When the bonding apparatus 100 starts operation, the substrates 180 are held one by one in the substrate holder 190 as shown in FIG. 2b.

  When the substrate holder 190 is the second one, as shown in FIG. 2 c, the stage is moved while monitoring the position with an interferometer, for example, so as to face the first substrate 180. Align. The aligned substrate 180 is temporarily bonded.

  As shown in FIG. 2D, the substrate 180 and the substrate holder 190 positioned in the aligner are connected by a plurality of stoppers 192 fitted in a groove 191 formed on the side surface, for example, to maintain the positioned state. The pair of connected substrates 180 and substrate holder 190 are conveyed together and inserted into the heating and pressing unit 240 as required.

  In this embodiment, the alignment accuracy in the aligner 140 is evaluated by the evaluation unit. In such a case, the substrate 180 that has been aligned and temporarily bonded in the aligner 140 is taken out of the substrate holder 190 before being carried into the heating and pressing unit 240 and carried into the evaluation unit. At this time, the substrate 180 and the substrate holder 190 are apparently in the form shown in FIG. 2e.

  FIG. 3 is a cross-sectional view schematically showing the structure of the evaluation gauge 18 used for evaluating the alignment accuracy in the aligner. The evaluation gauge 18 includes a transparent substrate 181, a semiconductor substrate 183, evaluation patterns 182 and 184, and alignment patterns 186 and 187.

  For the semiconductor substrate 183, a member equivalent to the substrate 180 to be bonded in the bonding apparatus 100 is used. Specifically, a Si wafer or the like can be arbitrarily selected. On the other hand, the transparent substrate 181 is formed of a material having a high transmittance with respect to inspection light described later. When using inspection light in the visible band, for example, a quartz substrate can be used. In addition, when using inspection light in the infrared band, a Si wafer can be used as the transparent substrate 181.

  In FIG. 3, the set of evaluation patterns 182 and 184 and the alignment patterns 186 and 187 are enlarged, but a plurality of sets of evaluation patterns 182, 184 and Alignment patterns 186 and 187 are formed.

  For example, the set of evaluation patterns 182 and 184 may have the same size as a single die of the stacked semiconductor device and may be arranged in the same manner as on the substrate 180. In addition, small evaluation patterns 182 and 184 may be formed in regions not used in the elements formed on the substrate 180.

  FIG. 4 is a plan view showing one set of evaluation patterns 182 and 184 and alignment patterns 186 and 187 extracted. Each of the evaluation patterns 182 and 184 includes a plurality of linear patterns formed at the same constant pitch 2p. The linear pattern has a line width such that, for example, the duty is 25% when viewed in the repeating direction of the evaluation patterns 182 and 184.

The alignment patterns 186 and 187 have shapes complementary to each other and are arranged in the vicinity of the evaluation patterns 182 and 184. Distance _{D 1} for the evaluation pattern 182 of one of the alignment pattern 186, with respect to the spacing _{D 2} of the evaluation pattern 184 of the other alignment pattern 187 has a difference in p corresponding to half the pitch 2p evaluation pattern 182 .

  FIG. 5 is a cross-sectional view of the evaluation patterns 182 and 184 when the transparent substrate 181 and the semiconductor substrate 183 are bonded. In the aligner 140, the transparent substrate 181 and the semiconductor substrate 183 are aligned so that the alignment patterns 186 and 187 coincide with each other, and are further pressed and temporarily joined.

When the transparent substrate 181 and the semiconductor substrate 183 are temporarily bonded, the alignment patterns 186 and 187 are integrated with each other. On the other hand, since the evaluation patterns 182 and 184 have different distances D ₁ and D ₂ with respect to the alignment patterns 186 and 187, linear patterns are alternately arranged.

  FIG. 6 is a plan view showing a state in which the synthesized evaluation patterns 182 and 184 are viewed from the transparent substrate 181 side. As shown, the alignment patterns 186 and 187 are integrated. On the other hand, the evaluation patterns 182 and 184 are nested with each other to form a composite pattern 188 that repeats a linear pattern at a pitch p. The transparent substrate 181 and the semiconductor substrate 183 including the composite pattern 188 formed in this way are used as the evaluation gauge 18 for evaluating the alignment accuracy of the aligner 140.

  FIG. 7 is a diagram schematically showing the structure of the evaluation unit 160 that evaluates the alignment accuracy of the aligner 140 using the evaluation gauge 18. An evaluation stage 168 on which the evaluation gauge 18 is mounted, an X drive unit 163, a Y drive unit 165, and a θ drive unit 167 that move or swing the evaluation stage 168, and a light source 162 that generates inspection light to be applied to the evaluation gauge 18. And an imaging unit 164 for observing the diffracted light generated in the inspection light by the evaluation gauge 18.

  The imaging unit 164 includes a curved reflecting mirror 169 that causes the inspection light generated by the light source 162 to be parallel light and incident on the evaluation gauge 18. Thereby, the inspection light is incident on each part of the evaluation gauge 18 at the same incident angle. Therefore, diffracted light is generated on the entire surface of the evaluation gauge 18 under the same conditions. Note that, as indicated by a dotted line in the figure, a plurality of imaging units 164 may be provided according to the order of the diffracted light to be observed.

  The evaluation gauge 18 is mounted on the evaluation stage 168 with the transparent substrate 181 side as an upper surface. The evaluation stage 168 also adsorbs and fixes the evaluation gauge 18 by electrostatic adsorption, vacuum adsorption or the like, similarly to the substrate holder 190 or the like. The light source 162 emits an inspection of a specific band or a specific wavelength designated in advance.

  The evaluation stage 168 is supported by the X driving unit 163, the Y driving unit 165, and the θ driving unit 167 stacked on each other. The X drive unit 163 moves the evaluation stage 168 along the guide unit 161 in the direction indicated by the arrow X in the drawing. The Y drive unit 165 moves the evaluation stage 168 on the X drive unit 163 in the direction indicated by the arrow Y in the drawing.

  Further, the θ drive unit 167 swings the evaluation stage 168 supported by the spherical seat on the Y drive unit 165. By the operations of the X driving unit 163, the Y driving unit 165, and the θ driving unit 167, the inspection light emitted from the light source 162 can be applied to the evaluation gauge 18 on the evaluation stage 168 at an arbitrary incident angle. Therefore, arbitrary diffracted light can be generated in the evaluation gauge 18 by changing optical conditions such as the irradiation angle of the inspection light.

  The light source 162, the curved reflecting mirror 169, and the imaging unit 164 may form a telecentric optical system. Thereby, the incident angles of the inspection light with respect to the evaluation gauge 18 and the imaging unit 164 are the same over the entire surface of the evaluation gauge 18, and the diffracted light can be observed at a time under uniform conditions. If the telecentric optical system is not used, the entire evaluation gauge 18 cannot be observed at a time under uniform conditions, but can be observed separately for each area of the evaluation gauge 18. However, the work efficiency of evaluation is reduced.

  FIG. 8 is a partial enlarged cross-sectional view showing a phenomenon that occurs in the evaluation gauge 18 irradiated with the inspection light. 8 is an enlarged view of the area surrounded by the dotted line A in FIG.

  As already described, each of the individual evaluation patterns 182, 184 and the composite pattern 188 forms a repetitive pattern having a constant pitch. Here, the evaluation patterns 182 and 184 each have a pitch 2p. When the transparent substrate 181 and the semiconductor substrate 183 of the evaluation gauge 18 are ideally aligned, the composite pattern 188 formed by synthesizing the evaluation patterns 182 and 184 is a repetitive pattern with a pitch p and a duty of 50%. Form.

Here, when the inspection light having the wavelength λ is incident on the repetitive pattern having the pitch p, reflected diffracted light is generated under the condition that the following expression 1 is satisfied.

Under the same conditions, the condition that the repetitive pattern with the pitch 2p generates diffracted light can be expressed as the following Expression 2.

On the other hand, the condition that the diffracted light of the inspection light incident on the repeating pattern with the pitch p cancels each other and does not generate diffracted light can be expressed by the following Equation 3.

  In the above formulas 2 and 3, for example, when the order n is n = 2m + 1, the two conditions are the same, and therefore, as shown in FIG. No order diffracted light is generated.

  FIG. 10 is a partially enlarged cross-sectional view showing a modification of the evaluation patterns 182 and 184. As shown in FIG. As shown in the figure, when the positions of the transparent substrate 181 and the semiconductor substrate 183 are shifted for some reason, the pitch of the composite pattern 188 formed by overlapping the evaluation patterns 182 and 184 each having the pitch 2p changes. That is, the pitch (p ± Δp) is obtained by increasing or decreasing the positional deviation amount Δp with respect to the ideal pitch p.

  FIG. 11 is a diagram showing the diffracted light intensity with respect to the pitch 2p generated by the evaluation patterns 182 and 184. As shown in FIG. As described above, when the pitch of the repetitive pattern of the pitch p is disturbed, the condition for canceling the first-order diffracted light is not satisfied, and the first-order diffracted light that has never existed appears. Therefore, by observing the change in the intensity of the first-order diffracted light, the presence or absence of misalignment can be determined and the alignment accuracy in the aligner 140 can be evaluated. That is, the first-order diffracted light intensity with respect to the pitch 2p increases and the second-order diffracted light decreases.

  Further, in the evaluation unit 160, the θ driving unit 167 is set at an angular position where the first-order diffracted light with respect to the pitch 2p can be received, so that the distribution of the local misregistration amount can be grasped collectively in the wafer. When there is no position shift, zero-order first-order diffracted light appears, so that the change can be easily detected by observing the change in the first-order diffracted light. However, since the second-order diffraction decreases as the first-order diffracted light increases, the second-order diffracted light may be observed. Further, the decrease in the first-order diffracted light with respect to the pitch p corresponding to the increase in the displacement of the positions of the transparent substrate 181 and the semiconductor substrate 183 may be measured. Indistinguishable from Origami).

  FIG. 12 is a graph showing the results of calculating the relationship between the shift amount of the substrate 180 and the first-order diffracted light intensity with respect to the pitch 2p by the RCWA (Rigorous Coupled Wave Analysis) method. In the RCWA method, incident light as an electromagnetic wave is developed into a plane wave for each wavelength, and the diffraction efficiency is obtained analytically.

  Monochromatic light is preferably used as the inspection light, and E-ray (wavelength 546 nm (TE polarized light)) is used here. Further, a quartz wafer is used as the transparent substrate 181, and a Si wafer is used as the semiconductor substrate 183.

  The refractive index of the quartz wafer was 1.46 and the thickness was 725 μm. The evaluation patterns 182 and 184 formed on the transparent substrate 181 and the semiconductor substrate 183 are formed of a resist having a refractive index of 1.52 and a thickness of 200 nm. Further, the Si wafer had a refractive index of 4.09-0.03i and a thickness of 725 μm.

  As shown in the figure, attention is focused on the first-order diffracted light when the 2p period is 0.3 μm. If it is ideally aligned and there is no displacement, no first-order diffracted light is generated.

  However, in the region where the positional deviation amount exceeds 20 nm, the pitch of the composite pattern 188 is deviated from p due to the positional deviation, so that the first-order diffracted light appears clearly. Furthermore, the intensity of the first-order diffracted light increases as the amount of misalignment increases. Accordingly, by preparing the evaluation patterns 182 and 184 having a 2p period of 0.3 μm and observing the increase in the intensity of the first-order diffracted light in the evaluation unit 160, the amount of misalignment can be grasped instantaneously.

  As described above, the first-order diffracted light intensity increases when the amount of positional deviation increases. For this reason, when the ideal alignment is performed, the first-order diffracted light does not appear at all. However, in order to effectively detect the first-order diffracted light, the emission intensity of the light source 162 or the sensitivity of the imaging unit 164 must be set appropriately.

  Therefore, when the positional deviation is evaluated with reference to the intensity of the first-order diffracted light, the reference pattern with the intentional pitch shifted is used as the evaluation pattern 182, so that it can be used when the light source 162 or the imaging unit 164 is calibrated. It is preferable to provide it together with 184. By providing such a reference pattern, it is possible to distinguish between a case where the imaging unit 164 is not sensitive for some reason and a case where the alignment is ideal.

  FIG. 13 is a graph showing the result of calculating the relationship between the shift amount of the substrate 180 and the intensity of the second-order diffracted light by the RCWA method. Note that the materials and specifications of the transparent substrate 181, the semiconductor substrate 183, and the evaluation patterns 182 and 184 used are the same as those in the calculation shown in FIG.

  Here, attention is focused on the second-order diffracted light when the 2p period is 0.7 μm. In the case of ideal alignment and no displacement, the composite pattern 188 formed by the evaluation patterns 182 and 184 forms a repetitive pattern with a pitch p. Corresponding to the composite pattern 188, strong second-order diffracted light is generated in the graph.

  However, in the region where the amount of misalignment exceeds 80 nm, the pitch of the composite pattern 188 deviates from p due to misalignment, so the second-order diffracted light is clearly reduced. Furthermore, the intensity of the second-order diffracted light decreases for a while as the positional deviation amount increases.

  Therefore, by preparing evaluation patterns 182 and 184 having a 2p period of 0.7 μm and observing a decrease in the intensity of the second-order diffracted light in the evaluation unit 160, the amount of positional deviation can be grasped instantaneously. Note that the evaluation unit 160 may be provided with a plurality of imaging units 164 to observe the first-order diffracted light intensity and the second-order diffracted light intensity simultaneously.

  FIG. 14 is a diagram schematically showing a specific method for evaluating the joining accuracy. That is, when attention is paid to specific diffracted light, the presence or absence of the positional deviation amount or the amount of the positional deviation amount is observed as a difference in brightness. Accordingly, as shown in FIG. 7, the entire substrate 180 to be evaluated is irradiated with inspection light, and the substrate 180 is collectively observed by the imaging unit 164, whereby the displacement amount distribution of the entire substrate 180 is distributed. Can be grasped instantly.

  In the example shown here, the amount of displacement is large in the element region 189 that appears bright. This makes it clear at a glance that the distribution of misalignment has a certain tendency.

  That is, the positional deviation amount to be evaluated can be quantified by previously theoretically and experimentally identifying the relationship between the diffraction intensity and the positional deviation amount with respect to the intended condition. Moreover, when using for a production line test | inspection, the acceptance criteria can be provided based on the relationship grasped | ascertained beforehand.

  FIG. 15 is a plan view showing another form of the evaluation patterns 182 and 184. As shown in the figure, in this evaluation gauge 18, two types of composite patterns in which the repeated directions of the composite patterns 188 are orthogonal to each other are mixed in one evaluation gauge. Thereby, the distribution of alignment accuracy in the aligner 140 can be grasped two-dimensionally.

  Note that the diffracted light is generated in the repeating direction of the composite pattern 188. Therefore, when simultaneously measuring the composite pattern 188 having different repeating directions, it is desirable to provide the evaluation unit 160 with a plurality of light sources 162 and a plurality of imaging units 164.

  Further, by irradiating the composite pattern 188 with inspection light vertically from a single light source 162, diffracted light can be simultaneously generated in the composite pattern 188 having different repeating directions. In this case, it is sufficient to provide a plurality of imaging units 164.

  Note that the types of repetition directions are not limited to two types orthogonal to each other. Therefore, a variety of evaluation patterns 182 and 184 having a repetitive direction corresponding to a stress having a high probability of occurring on the substrate 180 in the bonding apparatus 100 or the aligner 140 may be formed.

  FIG. 16 is a plan view showing another form of the evaluation patterns 182 and 184. In this embodiment, the composite pattern 188 formed by the evaluation patterns 182 and 184 is arranged on the scribe line generated between the element regions 189 where the elements are formed.

  With such an arrangement, the alignment accuracy can be evaluated using the composite pattern 188 in the manufacturing process of the stacked semiconductor device in which elements are formed in the element region 189. Further, since the scribe line disappears when the element region 189 is cut by dicing, the evaluation can be performed without reducing the utilization efficiency of the substrate 180.

  The arrangement of the composite pattern 188 is not limited to the scribe line. The composite pattern can be arranged not only on the outside of the element region 189 in the vicinity of the edge of the substrate 180 but also on an unused area inside the element region 189. Furthermore, the composite pattern 188 can be formed over the elements formed in the element region 189.

  In this way, by using the evaluation gauge 18 including a repeated pattern, the alignment accuracy distribution in the aligner 140 can be comprehensively and instantaneously grasped. Therefore, in the maintenance and inspection of the aligner 140, the state of the aligner can be grasped easily and quickly.

  Moreover, since the evaluation method using the evaluation patterns 182 and 184 requires a short time for the evaluation work, the alignment accuracy of the aligner 140 can be evaluated in the production process by mounting the evaluation unit 160 on the joining device 100. Therefore, it is possible to take measures such as loading the substrate 180 having undergone a remarkable positional shift into the aligner 140 again without sending it to the next step. Thereby, the yield of the material can be improved and the productivity of the stacked semiconductor device can be improved.

  Furthermore, the evaluation method using the evaluation patterns 182 and 184 can also be applied to inspection of a stacked semiconductor device that has become a product. That is, it is generated in the heating and pressurizing unit 240 by evaluating the stacked semiconductor device that is heated and pressed by the heating and pressurizing unit 240 in the bonding apparatus 100 and using the evaluation patterns 182 and 184. Can also be evaluated. In other words, the operation accuracy of the heating and pressing unit 240 can also be evaluated by the evaluation unit 160 and the evaluation method using the evaluation gauge 18.

  FIG. 17 is a diagram schematically illustrating another structure of the evaluation unit 160. In this evaluation unit 160, the same reference numerals are assigned to the same elements as those of the evaluation unit 160 shown in FIG. The evaluation unit 160 includes an illumination optical system 261 and an imaging optical system 263 that include optical paths formed symmetrically with respect to the evaluation gauge 18.

  The illumination optical system 261 includes a light source 162, a polarizing filter 262, and a curved reflecting mirror 169. The illumination light emitted from the light source 162 is irradiated to the evaluation gauge 18 from the transparent substrate 181 side through the polarizing filter 262 and the curved reflecting mirror 169.

  The polarizing filter 262 transmits only the linearly polarized light having a preset specific polarization plane among the illumination light incident from the light source 162. Thereby, the illumination light incident on the evaluation gauge 18 can be linearly polarized light. However, the polarizing filter 262 can be removed from the optical path of the illumination light.

  Further, when the polarizing filter 262 is inserted on the optical path of the illumination optical system 261, it can be rotated in the plane of the polarizing filter 262. Thereby, the polarization plane of linearly polarized light irradiated to the evaluation gauge 18 can be arbitrarily set.

  The curved reflector 169 forms a telecentric optical system for the light source 162 and the evaluation gauge 18. As a result, the illumination light reflected by the curved reflecting mirror 169 is incident on each region of the evaluation gauge 18 as telecentric light.

  The light source 162, the polarizing filter 262, and the curved reflecting mirror 169 can be moved individually. Thereby, the irradiation angle of illumination light can also be changed according to the measuring object mentioned later.

  The imaging optical system 263 includes a curved reflecting mirror 169, a polarizing filter 264, and an imaging unit 164. The illumination light reflected by the evaluation gauge 18 enters the imaging unit 164 through the curved reflecting mirror 169 and the polarization filter 264. The curved reflecting mirror 169 forms a telecentric optical system for the evaluation gauge 18 and the imaging unit 164.

  The polarizing filter 264 transmits only the linearly polarized light having a preset specific polarization plane out of the illumination light reflected by the evaluation gauge 18 and makes it incident on the imaging unit 164. However, the polarizing filter 264 can be removed from the optical path of the imaging optical system 263.

  Further, when the polarizing filter 264 is inserted on the optical path of the imaging optical system 263, the polarizing filter 264 can be rotated in the plane of the polarizing filter 264. Thereby, the polarization plane of linearly polarized light imaged by the imaging unit 164 can be arbitrarily selected.

  The evaluation gauge 18 has a plurality of element regions 189 as in the evaluation gauge 18 shown in FIG. Each of the element regions 189 has a composite pattern 188 including a repetitive pattern whose repetitive direction is parallel or orthogonal to the orientation flat.

  Further, as described with reference to FIGS. 3 to 6, the composite pattern 188 is formed by bonding the transparent substrate 181 and the semiconductor substrate 183 each having the evaluation patterns 182 and 184 and the alignment patterns 186 and 187 having a pitch 2p. Formed. Therefore, when the transparent substrate 181 and the semiconductor substrate 183 are joined, if the positional deviation does not occur, the pitch of the composite pattern 188 is p.

  By mounting the evaluation gauge 18 as described above on the evaluation unit 160 in which the polarizing filters 262 and 264 are removed from the optical path of the illumination light, the positional deviation between the transparent substrate 181 and the semiconductor substrate 183 can be evaluated. That is, as described with reference to FIGS. 8 to 11, the inspection light emitted from the light source 162 is incident on the evaluation gauge 18, and the diffracted light intensity of a specific order generated in the evaluation gauge 18 is measured by the imaging unit 164. By doing so, it is possible to detect a displacement between the transparent substrate 181 and the semiconductor substrate 183 forming the evaluation gauge 18.

  FIG. 18 is a diagram schematically illustrating an optical structure of the evaluation unit 160 in a state where both of the pair of polarizing filters 262 and 264 are enabled. Note that the same reference numerals are assigned to elements common to those in FIG. 17 and redundant description is omitted.

  As shown in the drawing, in the illumination optical system 261, a light source 162, a polarizing filter 262, and a curved reflecting mirror 169 are arranged so that the incident angle of the illumination light with respect to the evaluation gauge 18 forms an angle of 45 ° with respect to the composite pattern 188. The As a result, the polarization plane of the illumination light also forms an angle of 45 ° with the composite pattern 188.

  In the imaging optical system 263, the curved surface is formed so that light that has become elliptically polarized light due to structural birefringence (described later) in the composite pattern 188 enters the imaging unit 164 via the curved reflector 169 and the polarization filter 264. A reflecting mirror 169, a polarizing filter 264, and an imaging unit 164 are provided. Specifically, it is arranged at a position for receiving reflected light by regular reflection of illumination light incident from the illumination optical system 261.

  Here, the polarizing filters 262 and 264 are arranged so that the polarization planes of the linearly polarized light that is transmitted are orthogonal to each other, and form crossed Nicols.

  When linearly polarized light is incident on a fine repetitive pattern at an inclined incident angle, the component parallel to the repetitive pattern of the composite pattern 188 is orthogonal to the component perpendicular to the component birefringence (form birefringence). ) Is generated. For this reason, the emitted light from the composite pattern 188 becomes elliptically polarized light. Note that a component perpendicular to the linearly polarized light on which the vibration plane is incident (hereinafter referred to as a polarized light vertical component) of the elliptically polarized light is an optical characteristic (refractive index) of the material forming the composite pattern 188, and It varies depending on the shape. The component of elliptically polarized light that is parallel to the incident linearly polarized light also changes depending on the optical characteristics (refractive index) of the material forming the composite pattern 188, the shape of the composite pattern 188, etc., but the original signal Since the change ratio with respect to the intensity is smaller than that of the polarized light vertical component, the polarized light vertical component is preferable for observation.

  On the other hand, the polarization filter 264 of the imaging optical system 263 transmits only the polarization vertical component. The polarization perpendicular component in the composite pattern 188 varies depending on the ratio between the resist material forming the composite pattern 188 and the gap (for example, filled with air) of the linear pattern forming the composite pattern 188.

  FIG. 19 is a diagram schematically showing a cross-sectional shape of the resist layer 185 in the evaluation gauge 18. As shown in FIG. 19R, in the case of an ideal evaluation gauge 18 in which the transparent substrate 181 and the semiconductor substrate 183 are not displaced and the resist layer 185 forming the composite pattern 188 is not deformed, the transparent substrate 181 and the semiconductor In the gap between the substrates 183, the resist layers 185 and the gaps are alternately arranged at the same ratio.

  In contrast, in the evaluation gauge 18 shown in FIG. 19 (S1), the transparent substrate 181 and the semiconductor substrate 183 are misaligned as in the case shown in FIG. In the following description, the amount of displacement is indicated by S1. Further, in the evaluation gauge 18 shown in FIG. 19 (S2), in the resist layer 185 formed on the transparent substrate 181 side, a part of the pattern constituting the resist layer 185 is crushed by pressure, so that the crushed pattern The resist layer is deformed to increase the line width. In the following description, the amount of pattern deformation is indicated by S2 in the drawing.

  Further, in the evaluation gauge 18 shown in FIG. 19 (S3), a deformation occurs in which the cross-sectional shape of the resist layer 185 formed on the transparent substrate 181 side is changed. Furthermore, in the evaluation gauge 18 shown in FIG. 19 (S4), the entire resist layer 185 is crushed by the pressurization, so that the line width of the pattern constituting the resist layer 185 changes. Further, in the evaluation gauge 18 shown in FIG. 19 (S5), the entire resist layer 185 is crushed by pressurization, so that the entire pattern constituting the resist layer 185 is deformed so that its cross-sectional shape changes. In the following description, the respective deformation amounts are indicated by S3, S4, and S5.

  FIG. 20 is a graph showing the result of calculating the relationship between the intensity of the polarization vertical component and the positional deviation amount S1 measured by the imaging unit 164 for the evaluation gauge 18 having the positional deviation shown in FIG. 19 (S1) by optical simulation. is there. In the graph shown in FIG. 20, the x-axis is... And the y-axis is. As shown in the figure, the linearly polarized light intensity changes according to the change in the positional deviation amount S1, but it can be seen that the change is small.

  FIG. 21 shows the result of calculating the relationship between the intensity of the polarization vertical component and the deformation amount S2 measured by the imaging unit 164 with respect to the evaluation gauge 18 having the deformation shown in FIG. 19 (S2) by the optical simulation. It is a graph. In the graph shown in FIG. 21, the x-axis is... And the y-axis is. As shown in the figure, it can be seen that the intensity of the polarization vertical component changes greatly according to the change of the deformation amount S2.

  Similarly, in FIG. 22, FIG. 23, and FIG. 24, the imaging unit 164 measured the evaluation gauge 18 in which the resist layer 185 has the deformation shown in FIG. 19 (S3), FIG. 19 (S4), and FIG. 5 is a graph showing the result of calculating the relationship between the intensity of the polarization vertical component and the deformation amounts S3, S4, and S5 by optical simulation. In the graphs shown in FIG. 22, FIG. 23 and FIG. 24, the x-axis is... And the y-axis is. As shown in the figure, the intensity of the polarization vertical component changes according to changes in the deformation amounts S3, S4, and S5.

  If it is confirmed before bonding that the evaluation gauge patterns formed on the transparent substrate 181 and the semiconductor substrate 183 are correctly formed without deformation, the deformations of S2, S3, and S5 in FIG. 19 are small and ignored. be able to. In this case, the deformation is the displacement amount S1 and the deformation amount S4.

  Since the diffracted light intensity at the pitch 2p changes with respect to the change in the positional deviation amount S1, and hardly changes with respect to the change in the deformation amount S4, the relationship between the joining misalignment and the diffracted light intensity is obtained in advance. In this case, the size of the misalignment can be obtained from the diffracted light intensity.

  On the other hand, the intensity of the polarization perpendicular component changes small with respect to the change in the positional deviation amount S1, and changes greatly with respect to the change in the deformation amount S4. In the case where high accuracy is not required, ignoring the change with respect to the change in the positional deviation amount S1, and obtaining the relationship between the deformation amount S4 and the intensity of the polarization vertical component in advance, from the intensity of the component perpendicular to the linear polarization, The deformation amount S4 can be obtained.

  When high accuracy is required, a change in the polarization vertical component intensity with respect to the change in the positional deviation amount S1 and a change in the polarization vertical component intensity with respect to the change in the deformation amount S4 are obtained in advance, and the positional deviation amount S1 is first determined from the diffracted light intensity. Next, the amount of change in the polarization vertical component intensity with respect to the change in the positional deviation amount S1 is obtained, and the deformation is obtained by subtracting the amount of change in the polarization vertical component with respect to the change in the positional deviation amount S1 from the entire amount of change in the polarization vertical component intensity. Since the change amount of the polarization vertical component with respect to the amount S4 is obtained, the deformation amount S4 can be obtained with high accuracy therefrom.

  The relationship between the positional deviation amount S1 and the deformation amount S4, the diffracted light intensity, and the polarization perpendicular component intensity may be obtained experimentally in advance or may be obtained by optical simulation. Alternatively, it may be obtained by preparing a reference gauge having the same structure as the evaluation gauge 18 and having a known positional shift or deformation of the resist layer 185.

  On the other hand, when S2, S3, and S5 cannot be ignored, it is difficult to separate S2 and S3. Similarly, it is difficult to separate S4 and S5, so there are three types of S1, S2 / S3, and S4 / S5. It is realistic to classify and find these quantities. In this case, since there are three parameters, these quantities can be obtained by performing measurement under three types of optical conditions. For example, three types of measurements may be performed: first-order diffracted light with a pitch of 2p, third-order diffracted light, and polarization change.

  In the above example, the transparent substrate 181 and the semiconductor substrate 183 on which the evaluation patterns 182 and 184 having the pitch 2p are formed are bonded for the purpose of evaluating the positional deviation between the transparent substrate 181 and the semiconductor substrate 183 together. However, when the object of evaluation is limited to the deformation of the line width and cross-sectional shape of the resist layer 185, other structures may be used.

  FIG. 25 is a diagram schematically illustrating another structure of the evaluation unit 160. Note that the same reference numerals are assigned to the same elements as those in FIGS. 7 and 17, and redundant description is omitted.

  The evaluation unit 160 shown in FIG. 25 adds changeable filters 262 and 264 to the optical system for diffracted light observation to the evaluation unit 160 shown in FIG. 7 and moves the θ driving unit 167 to correct the illumination light. The reflected light is configured to enter the imaging unit 164. With such a structure, it is possible to observe the diffracted light and the vertical polarization component with a common optical system only by inserting / removing the changing filters 262 and 264 and controlling the θ driving unit 167, and the evaluation unit 160 is small and inexpensive. Can be configured.

  FIG. 26 is a cross-sectional view showing another structure of the evaluation gauge 18. As shown in the figure, the evaluation gauge 18 is formed by bonding a transparent substrate 181 having an evaluation pattern 182 and an alignment pattern 186 having a pitch p, and a semiconductor substrate 183 having an alignment pattern 187. By using the evaluation gauge 18 having such a structure, in the measurement result of the polarization perpendicular component, the line width and the cross-sectional shape deformation of the resist layer 185 are accurately detected regardless of the positional deviation of the transparent substrate 181 and the semiconductor substrate 183. it can.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that it can be realized in any order unless it is explicitly indicated as “,” etc., and the output of the previous process is not used in the subsequent process. Regarding the operational flow of the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for the sake of convenience, it means that it is essential to carry out in this order. is not.

1 is a plan view schematically showing the entire structure of a bonding apparatus 100. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is sectional drawing of the evaluation patterns 182 and 184. It is a top view of evaluation patterns 182 and 184. It is sectional drawing of the synthesis | combination evaluation patterns 182 and 184. FIG. It is a top view of synthesized evaluation patterns 182 and 184. It is a figure which shows the structure of the evaluation part 160 typically. It is a partial expanded sectional view which shows the phenomenon in the evaluation patterns 182 and 184. It is a figure which shows the diffracted light intensity produced by the evaluation patterns 182 and 184. It is a partial expanded sectional view showing modification of evaluation patterns 182 and 184. It is a figure which shows the diffracted light intensity produced by the evaluation patterns 182 and 184. It is a graph which shows the relationship between the deviation | shift amount of the board | substrate 180, and 1st-order diffracted light intensity. It is a graph which shows the relationship between the deviation | shift amount of the board | substrate 180, and a 2nd-order diffracted light intensity. It is a figure which shows typically the evaluation method of joining precision. It is a top view which shows the other form of the evaluation patterns 182 and 184. It is a top view which shows the other form of the evaluation patterns 182 and 184. It is a figure which shows typically the other structure of the evaluation part 160. FIG. It is a figure which shows the optical structure of the evaluation part 160 typically. It is sectional drawing which shows the model of the resist layer 185 for evaluation typically. It is a graph which shows the change of the polarization intensity which the imaging part 164 detects. It is a graph which shows the change of the polarization intensity which the imaging part 164 detects. It is a graph which shows the change of the polarization intensity which the imaging part 164 detects. It is a graph which shows the change of the polarization intensity which the imaging part 164 detects. It is a graph which shows the change of the polarization intensity which the imaging part 164 detects. It is a figure which shows typically the other structure of the evaluation part 160. FIG. 6 is a cross-sectional view showing another structure of the evaluation gauge 18. FIG.

Explanation of symbols

18 Evaluation gauge, 100 Bonding device, 101 Case, 102 Room temperature part, 111, 112, 113 Substrate cassette, 120 Control panel, 130 Pre-aligner, 140 Aligner, 141 Upper stage, 142 Lower stage, 144 Interferometer, 145, 210 Thermal insulation Wall, 146, 222, 224 Shutter, 150 Holder Stocker, 160 Evaluation Unit, 161 Guide Unit, 162 Light Source, 163 X Drive Unit, 164 Imaging Unit, 165 Y Drive Unit, 167 θ Drive Unit, 168 Evaluation Stage, 169 Curved Reflection Mirror, 171, 172, 230 Robot arm, 180 substrate, 181 Transparent substrate, 182, 184 Evaluation pattern, 183 Semiconductor substrate, 185 Resist layer, 186, 187 Alignment pattern, 188 Composite pattern, 189 Device area, 190 substrate Folder, 191 groove, 192 stop, 202 high temperature section, 220 airlock 240 pressurizing and heating unit, 261 an illumination optical system, 262, 264 polarizing filter, 263 an imaging optical system

Claims (35)

A bonding evaluation method for evaluating bonding accuracy when bonding a pair of substrates,
A bonding step of bonding a pair of substrates with an evaluation pattern layer having a repeated pattern repeated at a constant period;
A polarization measuring step comprising: irradiating the evaluation pattern layer with polarized light that passes through one of the pair of substrates, and measuring a change in a polarization state of light emitted from the evaluation pattern layer. In the measuring step, the polarized light is linearly polarized light,
The bonding evaluation method according to claim 1, wherein the polarization state is measured by an intensity of a polarization vertical component that is a polarization component perpendicular to the linearly polarized light in light emitted from the evaluation pattern layer.   The bonding according to claim 2, further comprising an evaluation step of evaluating that the deformation of the evaluation pattern is large when the intensity of the polarization perpendicular component measured in the polarization measurement step is largely different from a predetermined reference intensity. Evaluation methods. The joining step includes
Including a part of the repetitive pattern, and forming a first partial pattern layer formed on one of the pair of substrates;
Including a pattern obtained by removing the partial pattern included in the first partial pattern layer from the repetitive pattern, and further comprising forming a second partial pattern layer formed on the other of the pair of substrates, The joining evaluation method according to any one of claims 1 to 3, wherein the pair of substrates are joined with the first partial pattern layer and the second partial pattern layer facing each other.   The polarization measurement step further includes a determination step of determining the bonding accuracy according to the measured change in the polarization state with reference to the relationship between the previously obtained bonding accuracy and the change in the polarization state. The joint evaluation method according to any one of the above.   The diffracted light measurement step of irradiating the evaluation pattern layer with inspection light that passes through one of the pair of substrates and measuring the intensity of the diffracted light generated in the evaluation pattern layer. The joint evaluation method according to any one of the above. The previously determined relationship between the intensity of the polarization perpendicular component and the intensity of the diffracted light and the bonding accuracy
The bonding evaluation method according to claim 6, further comprising: a determination step of determining bonding accuracy in accordance with the measured change in polarization state and intensity of diffracted light.   The bonding evaluation method according to claim 7, wherein in the determining step, bonding accuracy is determined by separating the positional deviation between the pair of substrates and the deformation of the pattern layer.   Due to the deformation of the evaluation pattern, the positional deviation amount of the pair of bonded substrates is obtained from the diffracted light intensity, and the change amount of the polarization state corresponding to the positional deviation amount is subtracted from the measured polarization state change amount. The bonding evaluation method according to claim 7, further comprising a step of extracting the amount of change in polarization state.   The bonding evaluation method according to claim 1, wherein the polarization measurement step is performed on the pair of substrates heated and pressurized after the bonding step. A substrate holding unit for holding a bonded substrate including an evaluation pattern layer having a repeated pattern repeated at a constant period, and a pair of substrates bonded with the evaluation pattern layer interposed therebetween;
A polarization illumination unit that irradiates the evaluation pattern layer of the bonded substrate held by the holding unit with polarized light that passes through one of the pair of substrates;
A bonding evaluation apparatus comprising: a polarization measuring unit that measures a change in a polarization state of light emitted from the evaluation pattern layer. The polarized illumination unit irradiates linearly polarized light,
The bonding evaluation apparatus according to claim 11, wherein the polarization measuring unit measures the intensity of a polarization vertical component that is a polarization component perpendicular to the linearly polarized light in the light emitted from the evaluation pattern layer.   The bonding evaluation apparatus according to claim 11, wherein the linearly polarized illumination unit includes a telecentric optical system and irradiates the linearly polarized light that is telecentric to the evaluation pattern layer.   The bonding evaluation apparatus according to claim 11, further comprising a telecentric optical system that causes light emitted from the evaluation pattern layer to enter the polarization measuring unit.   The polarization measuring unit includes a reference unit that stores a relationship between a joining accuracy and a polarization state change obtained in advance, and a determination unit that determines the joining accuracy according to a change in polarization state measured with reference to the reference unit. The joint evaluation apparatus according to any one of claims 11 to 14, further comprising: An inspection light illumination unit that irradiates the evaluation pattern layer of the bonded substrate held by the holding unit with inspection light that passes through one of the pair of substrates;
The bonding evaluation apparatus according to claim 11, further comprising: a diffracted light measuring unit that measures the intensity of diffracted light generated in the evaluation pattern layer.   The determination unit further includes an evaluation unit that evaluates the bonding accuracy in accordance with the relationship obtained in advance between the bonding accuracy, the change in polarization state and the intensity of diffracted light, and the measured change in polarization state and intensity of diffracted light. The joint evaluation apparatus according to claim 16.   The bonding evaluation apparatus according to claim 17, wherein the determination unit determines the bonding accuracy by separating the positional deviation and the pattern deformation of the pair of bonded substrates.   The determining unit obtains the positional deviation amount of the pair of bonded substrates from the diffracted light intensity, and evaluates by subtracting the change amount of the polarization state corresponding to the positional deviation amount from the measured polarization state change amount. The bonding evaluation apparatus according to claim 17, further comprising a deformation extraction unit that extracts a change amount of a polarization state caused by deformation of the pattern. A bonding evaluation apparatus according to any one of claims 11 to 19,
A bonding apparatus for aligning and bonding one of the pair of substrates to the other;
A heating and pressurizing apparatus that heats and pressurizes and bonds the pair of substrates bonded by the bonding apparatus;
A substrate bonding apparatus comprising:   21. The bonding device is adjusted such that when the pair of substrates bonded by the bonding device is evaluated by the bonding evaluation device, the bonding accuracy of the pair of substrates satisfies a given evaluation standard. The board | substrate bonding apparatus of description.   When the pair of substrates bonded by the bonding apparatus is evaluated by the bonding evaluation apparatus, the pressure device is a pair of the substrates when the bonding accuracy of the pair of substrates satisfies a given evaluation criterion. The board | substrate bonding apparatus of Claim 20 or Claim 21 which bonds together.   23. The substrate bonding apparatus according to claim 20, wherein the evaluation device evaluates a bonding accuracy of the pair of substrates bonded by the pressure device. A bonding evaluation gauge for evaluating the bonding accuracy of a pair of substrates,
An evaluation pattern layer having a repeated pattern repeated at a constant period, and a pair of substrates bonded with the evaluation pattern layer interposed therebetween,
A bonding evaluation gauge that changes the polarization state of the outgoing light emitted from the evaluation pattern layer when the evaluation pattern layer is irradiated with polarized light that passes through one of the pair of substrates. The evaluation pattern layer is
A first partial pattern layer including a partial pattern of the repetitive pattern and formed on one of the pair of substrates;
The bonding according to claim 24, comprising: a pattern obtained by removing the partial pattern included in the first partial pattern layer from the repeated pattern; and a second partial pattern layer formed on the other of the pair of substrates. Evaluation gauge. The repeating pattern includes a plurality of parallel linear patterns arranged at regular intervals,
26. The joint evaluation gauge according to claim 25, wherein each of the first partial pattern layer and the second partial pattern layer includes the linear pattern extracted every other line from the repetitive pattern. Each of the pair of substrates further includes an alignment index arranged at a known relative position with respect to the first partial pattern layer or the second partial pattern layer,
27. The joint evaluation gauge according to claim 25 or claim 26, wherein the repetitive pattern is formed by the first partial pattern and the second partial pattern when the pair of substrates are joined with reference to the alignment index. .   The bonding evaluation gauge according to claim 24, wherein the evaluation pattern layer includes the repetitive pattern formed on one of the pair of substrates.   The bonding evaluation gauge according to any one of claims 24 to 28, wherein at least a part of the evaluation pattern layer is formed of a resist material.   30. The bonding evaluation gauge according to claim 24, wherein the evaluation pattern layer generates diffracted light when irradiated with inspection light having transparency to at least one of the pair of substrates.   The joining evaluation gauge according to any one of claims 24 to 30, wherein one of the pair of substrates includes a glass substrate.   32. The joint evaluation gauge according to claim 24, wherein the evaluation pattern layer includes a plurality of repeating patterns whose repeating directions intersect with each other.   The joint evaluation gauge according to any one of claims 24 to 32, wherein the evaluation pattern layer includes a plurality of repeating patterns having different repeating periods. An evaluation pattern layer having a repeated pattern repeated at a constant period and at least one is a semiconductor substrate, and a pair of substrates bonded with the evaluation pattern layer interposed therebetween;
And the polarization pattern of the polarized light emitted from the evaluation pattern changes when the evaluation pattern layer is irradiated with polarized light transmitted through one of the pair of substrates.   35. The stacked semiconductor device according to claim 34, wherein the evaluation pattern causes the inspection light to diffract when irradiated with inspection light that passes through one of the pair of substrates.

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