JP6012655B2 - Inspection condition data generation method and inspection condition data generation system for wafer inspection apparatus - Google Patents

Description

  The present invention relates to an inspection condition data generation method for a wafer inspection apparatus that automatically inspects the appearance of a fine circuit pattern or device chip formed on a substrate such as a wafer in a manufacturing process of a semiconductor device or an LED chip, and the like. The present invention relates to an inspection condition data generation system.

  Semiconductor devices and LED chips (hereinafter referred to as device chips) are manufactured by stacking circuit patterns on a substrate such as a silicon wafer or a glass substrate. In these manufacturing steps, circuit pattern formation and inspection are alternately performed a predetermined number of times in the manufacturing process, and then the device chip is cut out from the substrate into a predetermined size and packaged. In this circuit pattern forming process, an inspection using an automatic appearance inspection apparatus is performed for the presence or absence of defects such as scratches and foreign matter on the substrate and collapse of the circuit pattern (for example, Patent Document 1).

FIG. 10 is a plan view of a semiconductor wafer on which a plurality of patterns to be inspected are arranged.
FIG. 10 shows a state in which the semiconductor wafer Wz to be inspected is placed on the placement table 20. A plurality of chips Dz (n) (n = 1 to N) are patterned on the semiconductor wafer Wz. Further, the chip Dz (n) has the direction and order of arrows Vs indicated by broken lines in the drawing, that is, Dz (1), Dz (2), Dz (3), Dz (4),. Imaging is sequentially performed in the order of N). Each chip Dz (1) to Dz (N) imaged while moving in the above order is subjected to a predetermined inspection based on the imaged image.

  Further, in the automatic appearance inspection apparatus, in order to detect defects such as a circuit pattern formed on the inspection target object so as to be the same pattern, the luminance value of the detection image to be inspected and the luminance value of the reference image Are inspected for pattern defects while correcting the brightness (for example, Patent Document 2).

  Furthermore, when inspecting using a plurality of inspection devices, other inspection devices are considered based on the inspection condition data that has already been set and the device difference correction data for each device, taking into account the device differences for each inspection device. The inspection condition data is generated and inspected (for example, Patent Document 3).

Japanese Patent Publication No. 6-74972 JP 2005-158780 A JP 2010-239041 A

  FIG. 11 is a conceptual diagram showing how the brightness setting value is corrected for each device in the prior art. In the prior art, the brightness setting value is changed at a part having a predetermined reflectance, and the machine difference between apparatuses is corrected.

  That is, in the form in which inspection condition data of another wafer inspection apparatus is generated (so-called inspection condition data is shared) and inspected based on already set inspection condition data and machine difference correction data, the brightness Focusing on the correction, the reflectance on one reflecting surface of the inspection target area is treated as a representative value of the whole. For this reason, in the brightness correction according to the conventional technology, uniform brightness correction is performed regardless of the difference in the reflectance of each inspection target part. And in performing the pass / fail determination of each inspection target part, there is no problem even in such a form.

  However, when inspection target parts having different reflectivities are mixed, an error occurs in the correction of the reflectivity if the conventional brightness correction (that is, uniform brightness correction) is performed.

  FIG. 12 is a conceptual diagram showing how the brightness setting value is corrected for each device in the prior art. The correction characteristics are slightly different between a portion with a high reflectance and a portion with a low reflectance. It is shown.

  In other words, when a plurality of wafer inspection apparatuses are used, correction according to the reflectance is necessary in order to correctly determine the quality of the inspection target part.

  Therefore, the present invention reduces the error included in the luminance information for each inspection target part having a different reflectance even when a plurality of wafer inspection apparatuses are used, and allows inspection condition data of each inspection apparatus to be shared. It is an object to provide a generation method and an inspection condition data generation system.

In order to solve the above problems, the first aspect according to the present invention provides:
An inspection condition data generation method and an inspection condition data generation system for generating inspection condition data of one wafer inspection apparatus that performs inspection under the same inspection conditions as other wafer inspection apparatuses that have been operated first,
Using the other wafer inspection apparatus and the one wafer inspection device, for each,
A sample provided with a first reflecting portion on which a film having a first reflectance was formed, and a second reflecting portion on which a film having a second reflectance different from the first reflectance was provided. Prepare the sample,
Illumination light is irradiated toward the first reflecting unit with a first brightness setting value, and the intensity of light reflected from the first reflecting unit is set to the first brightness setting in the first reflecting unit. As a reflection luminance for the value,
Illumination light is irradiated to the first reflecting unit with the second brightness setting value set, and the intensity of light reflected from the first reflecting unit is set to the second brightness setting in the first reflecting unit. As a reflection luminance for the value,
Illumination light is irradiated toward the second reflecting portion with the first brightness setting value, and the intensity of light reflected from the second reflecting portion is set to the first brightness setting in the second reflecting portion. As a reflection luminance for the value,
Illumination light is irradiated toward the second reflecting unit with the second brightness setting value set, and the intensity of light reflected from the second reflecting unit is set to the second brightness setting in the second reflecting unit. As a reflection luminance for the value,
Based on the reflection luminance for the first brightness setting value in the first reflection unit and the reflection luminance for the second brightness setting value in the first reflection unit,
Calculating a characteristic of reflection luminance with respect to an arbitrary brightness setting value in the first reflection unit;
Based on the reflection luminance for the first brightness setting value in the second reflection unit and the reflection luminance for the second brightness setting value in the second reflection unit,
Calculating a characteristic of reflection luminance with respect to an arbitrary brightness setting value in the second reflection unit;
Based on the characteristic of reflected luminance for an arbitrary brightness setting value in the first reflecting unit and the characteristic of reflected luminance for an arbitrary brightness setting value in the second reflecting unit,
Calculate the characteristic of the reflected luminance for the part to be inspected with an arbitrary reflectance at an arbitrary brightness setting value,
Using the one wafer inspection device,
Characteristics of reflection luminance with respect to an inspection target part having an arbitrary reflectance at an arbitrary brightness setting value calculated by the one wafer inspection apparatus, and an arbitrary reflectance at an arbitrary brightness setting value calculated by the other wafer inspection apparatus Based on the characteristics of the reflected luminance for
The reflection luminance level is set for each part having a different reflectance of the inspection target part so that the reflection luminance for the inspection target part in the one wafer inspection apparatus becomes the same as the reflection luminance for the inspection target part in the other wafer inspection apparatus. Match.

  According to this configuration, one wafer inspection apparatus to be operated from now on is another wafer inspection apparatus that is already operating even when the inspection target parts having different reflectances are mixed in the wafer. It becomes possible to generate inspection condition data that can obtain the same inspection result as that inspected using.

In addition to the first aspect, the second aspect is
Defining a characteristic of reflected luminance with respect to an arbitrary brightness setting value in the first reflecting unit by a linear function, calculating a slope component and an intercept component in the linear function defining the characteristic of the reflected luminance;
A characteristic of reflected luminance with respect to an arbitrary brightness setting value in the second reflecting section is defined by a linear function, and an inclination component and an intercept component in the linear function defining the characteristic of the reflected luminance are calculated.

  The third aspect is the wafer inspection apparatus according to the first aspect or the second aspect.

  The fourth aspect is another wafer inspection apparatus according to the first aspect or the second aspect.

  Even when a plurality of wafer inspection apparatuses are used, the error included in the luminance information is reduced for each inspection target part having a different reflectance, and each inspection apparatus can share inspection condition data.

The conceptual diagram which shows an example of the other wafer test | inspection apparatus which uses this invention for implementation The conceptual diagram which shows an example of the one wafer inspection apparatus which uses this invention for implementation The top view which shows an example of the sample which uses this invention for implementation The figure which showed an example of the semiconductor chip patterned on the wafer The flowchart in an example of the form which embodies this invention Conceptual diagram showing reflection luminance characteristics for each reflectance and brightness setting value Conceptual diagram showing the brightness setting value and reflection luminance characteristics for each reflectance FIG. 2 is an external view of a substrate for inspecting the embodiment of the present invention. The conceptual diagram regarding the reflection luminance level adjustment process for embodying this invention The conceptual diagram regarding the reflection luminance level adjustment process for embodying this invention Plan view showing an example of a wafer on which a plurality of patterns to be inspected are arranged Conceptual diagram showing how the brightness setting value for each device is corrected in the prior art Conceptual diagram showing how the brightness setting value for each device is corrected in the prior art

DESCRIPTION OF EMBODIMENTS Embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a conceptual diagram showing an example of another wafer inspection apparatus that embodies the present invention.
FIG. 1 shows a perspective view of each component device and a block diagram of a configuration necessary for inspection by acquiring images for a wafer inspection apparatus A1 used for a wafer inspection system that performs inspection based on a captured image and generates inspection condition data. Are described in combination. In each figure, the three axes of the orthogonal coordinate system are X, Y, and Z, the XY plane is the horizontal plane, and the Z direction is the vertical direction. In particular, in the Z direction, the direction of the arrow is represented as the top, and the opposite direction is represented as the bottom.

  A wafer inspection apparatus A1 according to an example embodying the present invention includes a mounting table A20, a moving stage unit A2, an illumination unit A3, an imaging unit A4, an image processing unit A5, and an image acquisition unit A6. The inspection unit A7, the illumination intensity adjustment unit A8, the numerical calculation unit A9, and the control unit A10 are included. Further, the wafer inspection apparatus A1 includes a registration unit A11, an input unit A12, a display unit A13, and the like as necessary.

  The mounting table A20 is for mounting the substrate W to be inspected and has a flat surface in the XY direction. In the mounting table A20, grooves and pores are formed in a portion where a substrate to be inspected is mounted. Further, the grooves and pores are connected to a vacuum source and a compressed air source via an open / close valve.

  The moving stage unit A2 moves the mounting table A20 to an arbitrary position on the XY plane. The moving stage unit A2 includes an X-axis stage unit A21, a Y-axis stage unit A22, and a θ-axis table A23. The X-axis stage part A21 is mounted on the apparatus frame A18, and moves along the guide rail extending in the X direction at a predetermined speed and can be stopped at an arbitrary position. And a slider (not shown). The Y-axis slider A22 is mounted on the X-axis slider, and moves along the guide rail in the Y direction at a predetermined speed and can be stopped at an arbitrary position. And a slider (not shown). The θ-axis table A23 is mounted on the Y-axis slider, and the mounting table A20 attached to the θ-axis table A23 can be rotated or stopped in the θ direction with the z axis as the rotation axis. it can.

  Because of such a configuration, the moving stage unit A2 moves and rotates the mounting table A20 at a predetermined speed independently or in combination in the X direction, the Y direction, and the θ direction, so that an arbitrary position / Can be stationary at an angle.

  The illumination unit A3 irradiates light toward the substrate W to be inspected, and includes a light source unit A31. The light source unit A31 is connected to an illumination intensity adjusting unit 8 described later. In the light source unit A31, the intensity of light irradiated toward the substrate W changes according to the magnitude of the voltage / current sent from the illumination intensity adjusting unit 8.

  The light source unit A31 is attached to the lens barrel A40, and the light A32 emitted from the light source unit A31 is reflected by the half mirror A41 incorporated in the lens barrel A40, passes through the objective lens A44a, and irradiates the substrate W. Is done.

  Specifically, the light source unit A31 can be exemplified by an LED, a fluorescent lamp, a mercury lamp, a metal halide lamp, an incandescent lamp, a laser diode, and the like, and has a wavelength / intensity corresponding to the light receiving sensitivity of the imaging element A46 of the imaging unit A4 described later. Any device that emits light may be used. Examples of the light source unit A31 include those that are continuously lit, those that blink, and those that emit light appropriately according to a control signal from the outside (so-called strobe illumination). Here, an example using strobe illumination will be described.

  The strobe illumination is configured to repeat light emission at every predetermined feed pitch in cooperation with the movement of the X-axis slider A21 and the Y-axis slider A22 of the moving stage unit A2. The light source unit A31 is not limited to a form directly attached to the lens barrel A40, and may be a form in which light is guided from a light source installed in another place using a light guide.

  The imaging unit A4 images a pattern on the substrate W to be inspected, and includes a lens barrel A40, a half mirror A41, an objective lens A44a, and an imaging camera A45. The imaging camera A45 includes a light receiving element A46, and among the light A35 irradiated onto the substrate W, the light A42 reflected by the observation region V on the substrate W is converted into an objective lens A42a, a half mirror A41, An image that passes through the lens barrel A43 and is irradiated on the light receiving element A46 is output to the outside as image data.

  Specifically, the imaging camera A45 performs imaging simultaneously with the light emission of the strobe illumination, and outputs a video signal and image data of the captured image to the outside. At this time, since the light emission time of the strobe illumination is extremely short, even an image captured during movement is captured in a state like a still image.

  The image processing unit A5 acquires an image to be inspected output from the imaging camera A45, performs so-called image processing in accordance with a preset procedure, and performs determination and inspection. A6 and inspection part A7 are included.

  Specifically, the image processing unit A5 is configured by using a so-called image processing apparatus (hardware) and an execution program (software) thereof. More specifically, examples of the image processing apparatus include a unit type having an image processing function and a form using a board called an image processing board incorporated in a personal computer or a workstation.

  The image acquisition unit A6 acquires a pattern included in the observation region V on the substrate W imaged by the light receiving element A46 of the imaging camera A45 as image data. Specifically, a video input port and an image data input port of hardware constituting the image processing unit A5 can be exemplified.

  The inspection unit A7 performs pass / fail determination on a captured image to be inspected. Various examples of the quality determination of the specific captured image can be exemplified. For example, predetermined image processing is performed on the captured image, and pass / fail determination is performed based on the luminance value, the variance value, the CV value, or the like, or the pass / fail determination is performed by comparing with a pre-registered inspection reference image or an adjacent image. For example, it is possible to illustrate the form.

  The illumination intensity adjustment unit A8 adjusts the emission intensity of the illumination unit A3. Specifically, the illumination intensity adjustment unit 8 can be exemplified by a unit called a lamp power supply, and is supplied to the illumination unit A3 according to control signals and data sent from an external device (control unit A10 in the configuration of FIG. 1). The voltage and current can be adjusted.

  The numerical calculation unit A9 performs predetermined calculation processing on signals and data sent from each connected unit based on a pre-registered program and inspection condition data described later, and according to the calculation processing result , Outputs signals and data to each connected unit.

  Specifically, the numerical calculation unit A9 includes a personal computer, a workstation (hardware), and an execution program (software) thereof. As will be described in detail later, this execution program is programmed so that a series of steps (s11 to s19) necessary for realizing the present invention can be executed.

  The control unit A10 controls devices connected to each unit based on an operation pattern of a program registered in advance and inspection condition data described later. In the case of the wafer inspection apparatus A1 exemplified here, the control unit A10 is connected to the moving stage unit A2, the inspection unit A7, the illumination intensity adjustment unit 8, the numerical value calculation unit A9, the registration unit A11, the input unit A12, the display unit A13, and the like. Has been.

  Specifically, the control unit A10 can be exemplified by control devices such as a control board, a programmable logic controller (PLC), and a motion controller mounted on a personal computer or a workstation.

  The registration unit A11 registers inspection condition data, calculation processing results in the numerical calculation unit A9, acquired images and images after image processing, reflection luminance characteristics in each reflection unit, various information, various data, and the like. Specifically, the registration unit A11 can be exemplified by a hard disk, a semiconductor memory, and the like.

  The input unit A12 is for an operator to input information necessary for the operation of the wafer inspection apparatus A1. Specifically, the input unit A12 can be exemplified by an input device that performs character / number input, position designation, ON / OFF selection, and the like, such as a keyboard, a mouse, a touch panel, and a switch.

  The display unit A13 is for notifying the operator of the operation status, inspection results, status, and other information necessary for preparation / operation of the wafer inspection apparatus A1. Specifically, the display unit A13 can be exemplified by a display device such as a liquid crystal monitor or a lamp. Note that the wafer inspection apparatus A1 described above may be configured to include an audio output unit such as a buzzer or a speaker instead of the display unit A13 or in combination with the display unit A13.

  Since the wafer inspection apparatus A1 has the above-described configuration, the wafer inspection apparatus A1 continuously captures images while moving the mounting table A20 on which the substrate W to be inspected is mounted at a predetermined speed, and corresponds to the inspection target pattern. Image data can be acquired. Furthermore, an inspection based on the acquired captured image can be performed. The details of the generation of the inspection condition data used in the wafer inspection apparatus 1A will be described later.

FIG. 2 is a conceptual diagram showing an example of a wafer inspection apparatus that embodies the present invention.
FIG. 2 is a composite view of a perspective view of each device of the wafer inspection apparatus B1 used for performing inspection based on a captured image and generating inspection condition data, and a block diagram of a configuration necessary for image acquisition and inspection. Have been described.

  A wafer inspection apparatus B1 according to an example embodying the present invention includes a mounting table B20, a moving stage unit B2, an illumination unit B3, an imaging unit B4, an image processing unit B5, and an image acquisition unit B6. The inspection unit B7, the illumination intensity adjustment unit B8, and the control unit B9 are included. Furthermore, the wafer inspection apparatus B1 includes a registration unit B10, an input unit B12, a display unit B13, and the like. Note that the details of each configuration of the wafer inspection apparatus B1 are the same as those of the wafer inspection apparatus 1A described above, and thus the description thereof is omitted. The generation of inspection condition data used for the wafer inspection apparatus 1B will be described later in detail.

  In addition, there may be a wafer inspection device C1 having the same configuration as the wafer inspection devices A1 and B1. In this case, in applying the present invention, the wafer inspection apparatus C1 corresponds to one wafer inspection apparatus, and the wafer inspection apparatuses A1 and B1 correspond to other wafer inspection apparatuses.

(Wafer and imaging)
FIG. 3 is a plan view showing an example of a wafer which is a part of a form embodying the present invention.
On the wafer W, chips D (1) to D (52) having a predetermined size are arranged in a matrix at predetermined intervals. These chips D (1) to D (52) are formed by a plurality of patterning steps such as film formation, exposure, development, etching, and the like. For this reason, the reflectance varies depending on the part in the chip due to the material of the wiring pattern, the material of the film formed thereon, the difference in the film thickness, and the like.

  Here, for simplicity of explanation, each chip is represented by an image diagram, and each chip has a portion Ws1 having a first reflectance r1, a portion Ws2 having a second reflectance r2, and a third reflectance r3. This shows a state where the portion Ws3 exists. The sample used in the present invention may be one extracted from the actual semiconductor device manufacturing process, or a wafer (so-called “having a specially made portion having different reflectivity”). Standard work). In addition, as a sample used for this invention, the site | part (Ws1, Ws2) provided with the reflectances r1 and r2 which are at least 2 levels should just be sufficient.

FIG. 4 is a conceptual diagram showing a state of imaging in an example of a form embodying the present invention.
FIG. 4 shows a state in which the imaging cameras A45 and B45 sequentially capture images of the first chip D (1) to the fourth chip D (4) among the chips on the wafer W. . The imaging cameras A45 and B45 move relative to the wafer W in the direction of the arrow Vs. At the time shown in FIG. 4, the imaging cameras A45 and B45 are imaging the third chip D (3). Further, at this time, although optical components such as a lens are not shown, the range of the observation region V set slightly wider than the chip D (3) is projected onto the light receiving element 46.

  In implementing the present invention, the present invention is not limited to the form of strobe imaging as described above, and the imaging unit may be configured to continuously capture images using a line sensor. In this case, the illumination unit is not configured to emit strobe light but is configured to continuously irradiate light.

[Inspection condition data generation flow]
A typical inspection condition data generation flow in the wafer inspection apparatus A1 that has been operating first and the wafer inspection apparatus B1 that is about to operate will be described below.
FIG. 5 is a flowchart in an example of a form embodying the present invention, and a series of flows for generating inspection condition data is shown step by step. In the wafer inspection apparatuses A1 and B1, numerical operation units A9 and B9, control units A10 and B10, etc. are pre-programmed so that the following series of procedures can be performed automatically or semi-automatically with the intervention of an operator. Various necessary information and various data are registered in advance in the registration units A11 and B11.

(Sample preparation)
First, the wafer W, which is a sample substrate commonly used in the wafer inspection apparatus A1 and the wafer inspection apparatus B1, is prepared (step s1).
That is, the wafer W includes a first reflecting portion Ws1 that is a portion having a first reflectance r1, a second reflecting portion Ws2 that is a portion having a second reflectance r2, and a portion having a third reflectance r3. The third reflecting portion Ws3 is included.

(Calculation of reflection luminance characteristics in wafer inspection apparatus A1)
Next, this wafer W is mounted on the mounting table A20 of the wafer inspection apparatus A1 that has been operating first (step s10), and the following operations are performed.

  First, the illumination light A32 is irradiated toward the first reflecting portion Ws1 of the wafer W. At this time, the illumination intensity adjusting unit 8 sets the first brightness setting value x1 for the light source unit A31. In this state, the intensity of the light A42 reflected from the first reflecting unit is acquired as the reflected luminance g1 with respect to the first brightness setting value x1 in the first reflecting unit (step s11).

  Next, the illumination intensity adjustment unit 8 sets the second brightness setting value x2 to the light source unit A31, and subsequently irradiates the illumination light A32 toward the first reflection unit Ws1 of the wafer W. In this state, the intensity of the light A42 reflected from the first reflecting unit is acquired as the reflected luminance g2 with respect to the second brightness setting value x2 in the first reflecting unit (step s12).

  Next, the illumination light A32 is irradiated toward the second reflecting portion Ws2 of the wafer W. At this time, the illumination intensity adjusting unit 8 sets the first brightness setting value x1 for the light source unit A31. In this state, the intensity of the light A42 reflected from the second reflecting unit is acquired as the reflected luminance g3 for the first brightness setting value x1 in the second reflecting unit (step s13).

  Next, the illumination intensity adjustment unit 8 sets the second brightness setting value x2 to the light source unit A31, and subsequently irradiates the illumination light A32 toward the second reflection unit Ws2 of the wafer W. In this state, the intensity of the light A42 reflected from the first reflecting unit is acquired as the reflected luminance g2 with respect to the second brightness setting value x2 in the second reflecting unit (step s14).

  In addition, although the above-mentioned steps s11-s14 may be processed sequentially in time series, the first reflection part Ws1 and the second reflection part Ws2 are simultaneously irradiated with light of the same intensity, and the first reflection is performed. If the part Ws1 and the second reflection part Ws2 can be simultaneously imaged by the imaging camera A45, the following order may be used. That is, the illumination light is set to the first brightness setting value x1, and the first reflection part Ws1 and the second reflection part Ws2 are simultaneously irradiated to obtain the reflection luminances g1 and g3 of each part (Steps s11 and s13 are performed). Implementation). Thereafter, the illumination light is set to the second brightness setting value x2, and the first reflection part Ws1 and the second reflection part Ws2 are simultaneously irradiated to obtain the reflection luminance of each part (implementing steps s12 and s14). Alternatively, steps s12 and s14 may be performed first, followed by steps s11 and s13.

Next, based on the reflection luminance g1 with respect to the first brightness setting value x1 in the first reflection unit Ws1 and the reflection luminance g3 with respect to the second brightness setting value x2 in the first reflection unit Ws1, an arbitrary value in the first reflection unit The characteristic of the reflected luminance with respect to the brightness setting value is calculated (step s15).
Similarly, arbitrary brightness in the second reflecting unit based on the reflected luminance with respect to the first brightness setting value x1 in the second reflecting unit Ws1 and the reflected luminance with respect to the second brightness setting value in the second reflecting unit. The characteristic of the reflected luminance with respect to the set value is calculated (step s16).

  Here, a concept for deriving the characteristic of the reflection luminance from the reflection luminances g1, g2, g3, g4, the brightness setting values x1, x2, and the reflectances r1, r2 obtained in steps s11 to s14 will be described.

  FIG. 6 is a conceptual diagram showing the reflection luminance characteristics for each reflectance and brightness setting value. The brightness setting value is set for each of the first reflecting portion Ws1 having the reflectance r1 and the second reflecting portion Ws2 having the reflectance r2. It shows how the actual reflected luminance changes when it is changed, and shows the relationship between them.

  For example, in the first reflecting portion Ws1, when the brightness setting values are x1 and x2, they can be defined by Equation (1) approximated by a linear line passing through the luminances g1 and g2, respectively. ).

  That is, Formula (3) corresponds to a type of “characteristics of reflected luminance with respect to an arbitrary brightness setting value in the first reflecting portion” in the present invention.

  Similarly, in the second reflecting portion Ws2, when the brightness setting values are x1 and x2, they can be defined by Equation (4) approximated by a linear line passing through the luminances g3 and g4, respectively, and Equations (5) and (5) 6).

  That is, Formula (6) corresponds to a type of “characteristics of reflected luminance with respect to an arbitrary brightness setting value in the second reflecting portion” in the present invention.

Then, the reflection luminance characteristics with respect to the reflectances r1 and r2 are schematically shown in FIG.
FIG. 7 is a conceptual diagram showing the brightness setting value and the reflection luminance characteristics for each reflectance. For each of the brightness setting values x1 and x2, how the actual reflection luminance changes when the reflectance is changed. Or, the relationship between each other is illustrated.

  For example, the brightness setting value x1 can be defined by Equation (7) approximated by a linear line passing through the luminances g1 and g3 when the reflectances are r1 and r2. Further, the brightness setting value x2 can be defined by Equation (8) approximated by a linear line passing through the luminances g2 and g4 when the reflectances are r1 and r2.

Furthermore, when the brightness is set to an arbitrary brightness value x _n and the reflection luminances g _n and g ′ _n at the reflectivities r 1 and r 2 are defined, they can be expressed as equations (9) and (10). Further, as a general expression passing through the reflection luminances g _n and g ′ _n at the reflectances r1 and r2, an equation (11) approximated by a linear line with respect to an arbitrary reflectance r can be defined. ), (13).

  Therefore, Formulas (14) to (17) can be derived from Formulas (12) and (13).

  Therefore, Formulas (16), (17), and Formula (11) can be calculated based on the known reflectances r1, r2 and the acquired reflection luminances g1, g2, g3, g4.

That is, based on the characteristic of the reflected luminance for an arbitrary brightness setting value in the first reflecting unit and the characteristic of the reflected luminance for an arbitrary brightness setting value in the second reflecting unit,
It is possible to calculate the characteristic of the reflected luminance with respect to the inspection target part having an arbitrary reflectance r at an arbitrary brightness setting value _Xn (step s17).

(Calculation of reflection luminance characteristics in wafer inspection apparatus B1)
Although a series of procedures (steps s10 to s17) performed using the wafer inspection apparatus A1 has been described above, a similar series of procedures is performed using the wafer inspection apparatus B1 (steps s20 to s27).

(Reflection brightness level adjustment processing in wafer inspection apparatus B1)
Next, using the wafer inspection apparatus B1, the following reflection luminance level adjustment processing is performed (step s30).
In other words, in the reflection luminance level adjustment process,
Characteristics of reflection luminance with respect to an inspection target part having an arbitrary reflectance at an arbitrary brightness setting value calculated by the wafer inspection apparatus B1 and inspection target parts having an arbitrary reflectance at an arbitrary brightness setting value calculated by the wafer inspection apparatus A1 Based on the characteristics of reflected brightness against
A process of adjusting the reflection luminance level for each part having different reflectivity of the inspection target part is performed so that the reflection luminance for the inspection target part in the wafer inspection apparatus B1 is the same as the reflection luminance for the inspection target part in the wafer inspection apparatus A1. Is called.

  FIG. 8 is an appearance image diagram of a substrate to be inspected by embodying the present invention. Chips Db (1) to Db (52) to be inspected are patterned on the substrate W1, and each chip has a pattern. Each of the inspection target portions Wb1 to Wb3 having different reflectivities is included. In the substrate to be actually inspected, there are a large number (that is, in multiple stages) of reflectivities of the inspected part, but here, in order to explain simply, there are three levels of reflectivities rb1, rb2, and rb3. An example will be described.

  9A and 9B are conceptual diagrams relating to the reflection luminance level adjustment processing for embodying the present invention, and the reflection luminance level adjustment processing at the inspection target site Wb1 (reflectance rb1) in FIG. 8 is schematically illustrated. Is.

The wafer inspection apparatus A1 that has been operating first is set to the brightness setting value Xa, and the inspection target part with the reflectance r is the reflection luminance ga. In addition, the wafer inspection apparatus B1 that performs inspection under the same inspection conditions is set to the brightness setting value Xb, and the inspection target portion with the reflectance r is the reflection luminance gb.
Then, a process of converting the reflection luminance gb at the reflectance r into the reflection luminance ga is performed. Such a process is also performed for other inspection target parts Wb2 (reflectance rb2) and Wb3 (reflectance rb3) having different reflectivities.

  By doing so, the reflection luminance level is set so that the reflection luminance with respect to the inspection target part in the wafer inspection apparatus B1 is the same as the reflection luminance with respect to the inspection target part in the wafer inspection apparatus A1 for each part having different reflectance of the inspection target part. Can be combined.

  Note that a technique called so-called look-up table processing can be applied as processing for adjusting the above-described reflection luminance level. In this processing, the reflection luminances ga and gb at a certain reflectance r correspond to each other (so-called stringing), and a numerical value conversion table corresponding to these reflection luminances for each different reflectance of the examination target part. Registered. Therefore, the reflected luminance gb in the wafer inspection apparatus B1 is immediately converted to the reflected luminance ga in the wafer inspection apparatus A1.

  As a result, when the wafer inspection apparatuses A1 and B1 are inspected, the inspection target part acquired using the wafer inspection apparatus B1 can be inspected by the wafer inspection even if the reflection luminance is different for each part having a different reflectance of the inspection target part. It can be handled as a region to be inspected acquired with the same reflection luminance using the apparatus A1. Therefore, even if images are acquired with different brightness setting values in different apparatuses, it is possible to obtain an inspection result equivalent to the case where the same inspection apparatus inspects with the same brightness setting value. Note that the reflection luminance level adjustment step is not limited to the lookup table processing as described above, but may be configured such that the mutual correspondence is defined by a linear function or the like and can be calculated by arithmetic processing.

  The wafer inspection apparatuses A1 and B1 are provided with programs for performing the operations / processes as means for executing the operations / processes of the steps corresponding to the steps s11 to s30 described above. The wafer inspection apparatus B1 is provided with a program for generating inspection condition data as means for generating inspection condition data using these.

  In the above description, in order to simplify the description, the brightness setting value is set to 2 levels (x1, x2), the reflectance is set to 2 levels (r1, r2), and the reflection luminance characteristics are approximated by a linear line, respectively. However, the number of levels may be further increased and approximated by a polynomial of second order or third order. Alternatively, logarithmic approximation, power approximation, or exponential approximation may be used in accordance with the brightness setting value and reflectance characteristics.

  Because of such a configuration, the wafer inspection apparatus B1 to be operated will be inspected by using the wafer inspection apparatus A1 that has been operated first, even if the reflectance of the inspection target part varies from wafer to wafer. Inspection condition data that can be imaged with the same brightness as that of the case can be generated. The wafer inspection apparatus B1 can obtain the same inspection result as the wafer inspection apparatus A1 using the inspection condition data.

  Therefore, even when a plurality of wafer inspection apparatuses are used, errors included in the luminance information are reduced for each inspection target part having a different reflectance, and each inspection apparatus can share inspection condition data.

[Another form]
In steps s15, s16, s25, and s26 described above,
The characteristic of reflection luminance with respect to an arbitrary brightness setting value in the first reflection part and the characteristic of reflection luminance with respect to an arbitrary brightness setting value in the second reflection part are defined by linear functions, respectively, and a slope component in the linear function The procedure for calculating (so-called proportionality coefficient) and intercept component (so-called offset value) is shown. In this way, the process of adjusting the reflection luminance level in the above-described step s30 can be performed quickly, which can be said to be a preferable mode.

  By doing so, the inspection condition data can be easily generated in the wafer inspection apparatus B1 to be operated.

  Furthermore, when performing a more accurate reflection luminance level adjustment process, these reflection luminance characteristics may be defined by a multi-order function of a quadratic function or more, an exponential function, a logarithmic function, or other mathematical expressions. Even in such a case, the wafer inspection apparatuses A1 and B1 are means for executing the operation and processing of predetermined steps in order to calculate variable components and intercept components of the defined reflection luminance characteristics. (That is, a processing program) is provided.

  By doing so, in the wafer inspection apparatus B1 to be operated from now on, it becomes possible to generate inspection condition data having high reproducibility with the wafer inspection apparatus A1 that has been operated first.

A1 Wafer inspection equipment (other equipment)
B1 Wafer inspection device (one device)
A2, B2 Moving stage part A3, B3 Illumination part A4, B4 Imaging part A5, B5 Image processing part A6, B6 Image acquisition part A7, B7 Inspection part A8, B8 Illumination intensity adjustment part A9, B9 Numerical calculation part A10, B10 Control Part A11, B11 Registration part A12, B12 Input part A13, B13 Display part A18, B18 Device frame A20, B20 Mounting table A21, B21 X-axis slider A22, B22 Y-axis slider A23, B23 θ-axis table A31, B24 Light source part A32, B25 Emitted light A35, B26 Illumination intensity adjusting part A41, B41 Half mirror A42, B42 Reflected light A43, B43 Lens barrel A44, B44 Objective lens A45, B45 Imaging camera A46, B46 Light receiving element C1 Wafer inspection device (Another device)
W Wafer W11 Orientation Flat W12 Alignment Mark W12a Alignment Mark for Each Chip W13 Semiconductor Chip Circuit Pattern W14 Semiconductor Chip Circuit Part W15 Semiconductor Chip Electrode Part W16 Semiconductor Chip Group W17 Dimensional Reference Mark of Known Dimensions x1 First Brightness Setting Value x2 Second brightness setting value x _n any brightness setting value r1 first reflectance r2 second reflectance r3 third reflectance r _n arbitrary reflectance Ws1 first reflecting portion Ws2 second reflecting portion Ws3 third Reflector

Claims (4)

An inspection condition data generation method for generating inspection condition data of one wafer inspection apparatus that performs inspection under the same inspection conditions as other wafer inspection apparatuses that are operating first,
Using the other wafer inspection apparatus and the one wafer inspection device, for each,
A sample provided with a first reflecting portion on which a film having a first reflectance was formed, and a second reflecting portion on which a film having a second reflectance different from the first reflectance was provided. Prepare the sample,
Illumination light is irradiated toward the first reflecting unit with a first brightness setting value, and the intensity of light reflected from the first reflecting unit is set to the first brightness setting in the first reflecting unit. Obtaining as a reflected luminance for the value;
Illumination light is irradiated to the first reflecting unit with the second brightness setting value set, and the intensity of light reflected from the first reflecting unit is set to the second brightness setting in the first reflecting unit. Obtaining as a reflected luminance for the value;
Illumination light is irradiated toward the second reflecting portion with the first brightness setting value, and the intensity of light reflected from the second reflecting portion is set to the first brightness setting in the second reflecting portion. Obtaining as a reflected luminance for the value;
Illumination light is irradiated toward the second reflecting unit with the second brightness setting value set, and the intensity of light reflected from the second reflecting unit is set to the second brightness setting in the second reflecting unit. Obtaining as a reflected luminance for the value;
Based on the reflection luminance for the first brightness setting value in the first reflection unit and the reflection luminance for the second brightness setting value in the first reflection unit,
Calculating a characteristic of reflected luminance with respect to an arbitrary brightness setting value in the first reflecting unit;
Based on the reflection luminance for the first brightness setting value in the second reflection unit and the reflection luminance for the second brightness setting value in the second reflection unit,
Calculating a characteristic of reflected luminance with respect to an arbitrary brightness setting value in the second reflecting unit;
Based on the characteristic of reflected luminance for an arbitrary brightness setting value in the first reflecting unit and the characteristic of reflected luminance for an arbitrary brightness setting value in the second reflecting unit,
Performing a step of calculating a characteristic of reflected luminance with respect to an inspection target part having an arbitrary reflectance at an arbitrary brightness setting value;
Using the one wafer inspection device,
Characteristics of reflection luminance with respect to an inspection target part having an arbitrary reflectance at an arbitrary brightness setting value calculated by the one wafer inspection apparatus, and an arbitrary reflectance at an arbitrary brightness setting value calculated by the other wafer inspection apparatus Based on the characteristics of the reflected luminance for
The reflection luminance level is set for each part having a different reflectance of the inspection target part so that the reflection luminance for the inspection target part in the one wafer inspection apparatus becomes the same as the reflection luminance for the inspection target part in the other wafer inspection apparatus. An inspection condition data generation method for a wafer inspection apparatus, characterized in that a matching processing step is executed . Defining a reflection luminance characteristic with respect to an arbitrary brightness setting value in the first reflection unit by a linear function, and calculating a slope component and an intercept component in the linear function defining the reflection luminance characteristic;
A step of defining a reflection luminance characteristic with respect to an arbitrary brightness setting value in the second reflection unit by a linear function and calculating an inclination component and an intercept component in the linear function defining the reflection luminance characteristic is performed. A method for generating inspection condition data for a wafer inspection apparatus according to claim 1, characterized in that: An inspection condition data generation system for generating inspection condition data of one wafer inspection apparatus that performs inspection under the same inspection conditions as other wafer inspection apparatuses that are operating first,
Using the other wafer inspection apparatus and the one wafer inspection device, for each,
Irradiation light is set to the first brightness setting value toward the first reflecting portion on which the film having the first reflectance is formed, and the intensity of light reflected from the first reflecting portion is set as follows: Means for obtaining as a reflected luminance for the first brightness setting value in the first reflecting section;
Illumination light is irradiated to the first reflecting unit with the second brightness setting value set, and the intensity of light reflected from the first reflecting unit is set to the second brightness setting in the first reflecting unit. Means for obtaining as a reflection luminance for the value;
Illumination light is set to a first brightness setting value and irradiated to a second reflecting portion on which a film having a second reflectance different from the first reflectance is formed, and the second reflecting portion is irradiated. Means for acquiring the intensity of the light reflected from the first brightness setting value in the second reflection unit as a reflection luminance;
Illumination light is irradiated toward the second reflecting unit with the second brightness setting value set, and the intensity of light reflected from the second reflecting unit is set to the second brightness setting in the second reflecting unit. Means for obtaining as a reflection luminance for the value;
Based on the reflection luminance for the first brightness setting value in the first reflection unit and the reflection luminance for the second brightness setting value in the first reflection unit, reflection for an arbitrary brightness setting value in the first reflection unit. Means for calculating luminance characteristics;
Based on the reflection luminance for the first brightness setting value in the second reflection unit and the reflection luminance for the second brightness setting value in the second reflection unit, reflection for an arbitrary brightness setting value in the second reflection unit Means for calculating luminance characteristics;
Based on the characteristic of reflected luminance for an arbitrary brightness setting value in the first reflecting unit and the characteristic of reflected luminance for an arbitrary brightness setting value in the second reflecting unit,
Means for calculating a characteristic of reflected luminance with respect to an inspection target part having an arbitrary reflectance at an arbitrary brightness setting value;
Using the one wafer inspection device,
Characteristics of reflection luminance with respect to an inspection target part having an arbitrary reflectance at an arbitrary brightness setting value calculated by the one wafer inspection apparatus, and an arbitrary reflectance at an arbitrary brightness setting value calculated by the other wafer inspection apparatus Based on the characteristics of the reflected luminance for
The reflection luminance level is set for each part having a different reflectance of the inspection target part so that the reflection luminance for the inspection target part in the one wafer inspection apparatus becomes the same as the reflection luminance for the inspection target part in the other wafer inspection apparatus. A wafer inspection system comprising a processing means for matching. Means for defining a reflection luminance characteristic with respect to an arbitrary brightness setting value in the first reflection unit by a linear function, and calculating a slope component and an intercept component in the linear function defining the reflection luminance characteristic;
Means for defining a reflection luminance characteristic with respect to an arbitrary brightness setting value in the second reflection unit by a linear function, and calculating a slope component and an intercept component in the linear function defining the reflection luminance characteristic. The inspection condition data generation system for a wafer inspection apparatus according to claim 3, wherein the system is an inspection condition data generation system.

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