WO2004083776A1

WO2004083776A1 - Film thickness acquiring method

Info

Publication number: WO2004083776A1
Application number: PCT/JP2004/003555
Authority: WO
Inventors: So Aikawa
Original assignee: Japan Science And Technology Agency; Tecnos Co., Ltd.
Priority date: 2003-03-18
Filing date: 2004-03-17
Publication date: 2004-09-30
Also published as: TWI284729B; JP2004279296A; KR20050107511A; WO2004083776B1; KR100724374B1; JP3742801B2; TW200502524A

Abstract

A film thickness acquiring method which acquires the in-plane distribution of the thickness of a thin film provided on a flat plate by a simple structure, and which shines an irradiation light (4) from a chromatic light sources (3) or a light source (3) monochromated by a filter onto a film (2) to be measured formed on a substrate (1), measures a reflection light (5) undergone interference from the film (2) by a light receiving device (6) while the incident angle of the irradiation light (4) to the main surface of the film (2) is being changed stepwise, and acquires the thickness of the film (2) from those incident angles of the irradiation light (4) that maximizes and minimizes the varying light receiving intensity of the measured reflection light (5).

Description

Tree pofenno

The present invention relates to the advantage of the present invention, and it is easy to understand the distribution of difficulties when looking at each other.

The present invention relates to a method for obtaining Hi®, which has a glue layer as a method for obtaining the same. Crane technology

^^^ In the case of exposure, the decoration of the photoresist must be about j¾, which is the size of a large-scale ρ-square fiber. Need to rub the leak, especially

In order to increase the resilience, it is necessary to further improve the surface.

Occurrences of such difficulties are caused by the insects: There are two types, one using the change in polarization due to interference and the other using the change in dimension due to interference.

Among these, there is an ellipsometer as a type that uses the change in polarization due to interference. This is a device for checking the visual characteristics and the like.

Although there are observations that this night is wide-ranging and that root diseases such as the Nesin's membrane are also possible, the equipment is generally expensive.

On the other hand, in the case of using dimensional, if white is excited by a thin film, the size can be obtained according to the wavelength due to interference: the key is rtrt る).

This is measured by ^ §, and fitting with ^^ can be used to suppress ゃ? Or;

Also, by using the concealment of the ¾ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ I 利用 I (For example, H ¥ 5—5 6 9 9. In this wisteria, the angle itself is changed by changing the angle itself, and the bias of the two views is used. Method I is to calculate the refractive index n and 赙 d of raw grapes.

However, there is a mouth that ϋ ϋ ϋ できないしかできない的に的に ¾ ¾ 的に的に局所 ¾ 的に的に的に的に的に的に的に的に的に的に的に的に的に的に的に局所的に的に的に口口口口的に的に口. There is a drive to take it.

In addition, because of the lack of knowledge and wealth of imM, whether using an ellipsometer or, the approach of arranging measuring devices in an array and measuring wide awakening at the same time is also considered in H There is an announcement.

Therefore, in order to obtain a wide distribution of café distribution, it would be enormous if one tried to make ll parts at a high angle K, such as mosquitoes, which would be the power to force a sickness device along a rubber object, ^ I need to say.

In particular, the liquid says ^. With the advancement of the flannel, the BIT required in the future will increase.

On the other hand, the crane on the 5 开 5 6 9 9 Gourmet is a bracelet 彻 I ri ri # vermilion, which can be used as it is to measure the film thickness distribution of difficulties in 艮 ^^ There is a problem that it cannot be done, and even if it is reversed, there is a problem that a large amount of Btr is required for measurement and analysis.

Therefore, the aim of Shimei is to obtain the in-plane distribution of the difficulties provided at mh by simple difficulties. Breaking the invention

FIG. 1 is an explanatory diagram of Ryugetsu Makoto Yukari. Here, means for controlling ira on a shelf will be described with reference to FIG.

Fig fiber

(1) ± 1 In order to serve one's own purpose, the invention is that S Alternatively, irradiation light 4 i from one of the light sources 3 of the light source 3 monochromatic by the filter

1.The size of the fiber 2 provided on the fiber 1 and the interference of the object 2 caused by the ecstasy 5 was changed to the step light from the irradiation light 4 on the main surface of the fiber 2. It is characterized by acquiring the dragon fiber 2 hall from the dimensional angle of the irradiation light 4 which takes the maximum value and the minimum value at the measured light of 5 degrees at the angle of 5 degrees.

As described above, in the present invention, the change in recommendation is not regarded as a change in masculine explosion, but rather as a change in angle. Since it is good enough just to acquire the change, it is possible to simplify the simplicity and to set the required Bf ^ to: ^ 畐

In addition, a filter may be provided on the light source 3 side for monochromatization, or may be provided on the 置 ^ -position 6 side. become. In particular, since it is assumed that the refractive index of the object 2 provided on the fiber 1, which is the measurement, is vulnerable, the maximum value, the value j, and the value The measurement can be reduced because the HP can be obtained by using the pair.

(2) In addition, Shimei, in himself (1), wrote the wisdom of 光 light 5 of Wei Ping «and the pre-acquired 口 of the mouth! It is assumed that the! ¥ of ^! Is obtained by performing the fighting with H.

Like this, 赚 mouth ^! By acquiring in advance the S 寸 mitsu 5 »in S1? And deciphering the data in the evening, and intersecting with the S 狽 mitsu 5 ^ l ^« that disturbed this database, simply ^ You can take ^ ϋ.

(3) In addition, the present invention, ± ± self (1) or (2)

Assuming that a large distribution is obtained by using an area sensor type image sensor in a relationship between the angle II and the angle;

In this way, the area sensor type is used as the device 6. Using an image sensor With this, large data can be collected at once, and the film thickness of ^! The distribution can be obtained with Yasiao.

Note that the image sensor used for Jt ^ may be a CCD type area sensor or a CMOS type area sensor, and is not subject to sacrifice.

(4) Also, in the description, in JJH (3), the neighbour 2 is provided, and the power is increased while the number of steps corresponding to one pixel of the image sensor is changed. This is referred to as glue.

In this way, by moving the step by a distance of g corresponding to one pixel of the image sensor, the data of the ** with the image sensor can be obtained by standing the boat. Can be obtained.

(5) In addition, Hakumei, in ± 1 (4), selected the Weinen cloth at a given angle from the Wei plating of Wei sung light 5 obtained consecutively with the step method, In the same position, the size corresponding to one pixel of the image sensor on the fiber 1 — l shelf 1 ^; Obtain the distribution ^.

In this way, by finding the cloth at a predetermined angle of incidence for each dimension angle of the ^ S key of the intense light 5 obtained by fiber-shaping on a step, it is possible to obtain one pixel of the image sensor. At the same position of the corresponding size-¾ Dimension; the relationship of the subject can be easily 〖、, so that the 2 ^ ¾ distribution of the difficulty can be humiliated with »^ . A simple translation of the picture

FIG. 1 is an explanatory diagram of the configuration of the present invention.

FIG. 2 shows a purpose W used in the embodiment of the present invention. Fig. 3 is an explanatory diagram of the position zone system of the CCD camera and the measurement panel.

Figure 4 shows

FIG. 5 is an explanatory diagram of an image at a position n + 1, a position n, and a position n−1. FIG. 6 is an explanatory diagram of obtaining an angle—a size of a contact point of 7 mm.

Fig. 7 is the point in the middle of the tool? FIG. 4 is an explanatory diagram of the relationship of the age at which the stagnation occurs.

Fig. 8 is a Randetsu diagram of the boat at Ll 16, 8-273, 6 nm. Fig. 9 is L = 275.2-432. Figure 10 is a Nazotsuki view of dimension ^ boats in 0 nm is, L = 433. 6-523. 2 of dimensions in the nm IM Zudea Figure 11, tool control, to彻淀point [rho ₂ in Yodoyu FIG. 4 is an explanatory diagram of the Jt ^ X series.

FIG. 12 is an explanatory diagram of dimensions at L = 116.8 to 273.6 nm.

FIG. 13 is an explanatory diagram of ^ ffi at L = 275.2 to 432.0 nm. FIG. 14 is an explanatory diagram of reflected light plating at L = 433.6 to 523.2 nm. ^ & T for invention ^^

Here, Fig. 2 Nodan 6 will be used to explain Tokuo of Nada in Shimei.

See Figure 2

Fig. 2 is a schematic view of the l ^^^ ^ of the 用いる ^ ^ ^ used for the difficult clan of the present invention. The moving stage 14, which moves the moving stage 14 in one direction by fiber tangling the panel 13, the rail 15 for moving the moving stage 14, the motor 16 for controlling the stage Trigger signal for generating a trigger signal for controlling the CCD camera 12 from the stage position 17, and for extracting a specific wave 威 ^ of the intense light from the measurement panel 13 It is obtained from the band pass filter 18.

As the の # β ~ surface 麵 11, for example, using a normal sculpture, it is sufficiently removed on the surface light source surface! It is difficult to avoid the brightness and the brightness by the angle. The bandpass filter 18 is for simplifying the light from the surface 11, and it is desirable to use a bandpass filter that is as narrow as half iiil as much as possible.

Even if the band-pass filter 18 is not necessarily half-sized, it is possible to use the spectrum 14 characteristics of the plane 11 well and obtain something close to monochromatic light.

The surface light source 1 1 {using the touch field / df ^ is a bandpass filter 18 [W ^].

In addition, the trigger signal 17 is used for the CCD camera 12 to perform frame capture by moving the moving stage 14 by the steps of the power station.

A similar function can be provided by a sensor attached to the TRIGA, 7-movement stage 14 or RENOLA 15.

Also, at this point, the camera is tilted by 30 ° with the lead of the CCD camera 12 and tilted by 30 ° and jumped by & ^ n. Make it possible to reduce the sunshine.

In addition, the angle of view in the direction of R in the figure of the lens 19 of the CCD camera 12 is set to 40 °, and in conjunction with the fact that the CCD camera 12 has been turned around 30 °, this ^ ° Nenore

It is possible to make a light beam with a dimension angle of 50 °.

In addition,. The image captured by the camera 12 is distorted by the camera's tilt view and the butterfly of the lens 19. Regardless of the position of the moving stage 14, the illness panel 13 is designed so that the stomach image can be displayed in the same size and size. Note that J ^ using the (1 .0 camera 12 in the vertical i direction and using the lens 19 smaller by parentheses ^^ is this distortion ^ i! BW ^.

Also, for all images, such as the circumference of the lens 19 and the surface light source 11, perform the operation of 赚 (better, ffiE at this point).

In addition, the timing of the image of the image is as follows: the moving stage 14 is moved while the moving stage 14 is moved. Minutes: Triggers every time it moves. It is a leg that sends a word to the CCD camera 12 so that one person can move the measurement panel 13 with the mouse. Can be

The length of this constant step is equal to the length of one pixel in the CCD camera 12 [the target screen panel] in the image after the distortion.

Figure 3

FIG. 3 is a diagram in which only the coordinate systems of the CCD camera 12 and the パ yodopanenore 13 are extracted. In this figure, while the Koyodo panel 13 is moved from the position A to the position B, an image is drawn with one steel haze. Check the elephant.

Ezo obtained "¾ at this time, as is apparent from FIG, all on彻淀panel 1 3; de of when viewed from all angles between« to Te Contact Rere of through? ₂ - It will include evening.

Next, with reference to FIG. 4 No. 16, a male who obtains occlusion and angle of each point from an image acquired by JJ himself will be described.

See Figure 4

FIG. 4 is a transcript of the presentation, in which the CCD camera 12 is set at the height H, and indicates the position on the n- 2, n- 1, η · moving stage 14. The concealment of each of these positions is the length Δ on the festival panel 13 corresponding to 1 pixel for the image obtained by subjecting the resulting image to distortion Φ.

In addition, it is L from the point た from the CCD camera 12-.

Move the dilatation measurement panel 13 together with the fiber stage 14 Then, the image is obtained by moving the image by Δ, and the obtained image of “i” is assigned to the panel m, m + l, m + 2 ···.

In the figure, each panel is drawn as a set of columns, but this is intended to be one pixel column in the image after listening to E. There is no system.

As ϋ ^, m, m + 1, m + 2,-and ^ rise, the panel moves right and left on the same Δ at a time. It is shown shifted.

The pixel column at position n is hatched with a tree, the pixel column at position n + 1 is hatched with a downward-sloping Yudas, and the pixel column at position n-1 is a hatched upper right It is represented by / pitching.

Fig. 5 (a) to (c) m

Next, of the stunned images obtained as m, m + l, m + 2, ..., the same demagnification angle with respect to the CCD camera 1 1 Side by side »Obtain each picture symbol.

These ϋβ ·, m, m + 1, m + 2 · · · are connected to each other smoothly because they are distorted HE.

Fig. 5 (a) to (c)

FIGS. 5 (a) to 5 (c) show the images at the obtained positions n + 1, n, and n-1, respectively. The size of the measurement panel 13 of 1 at the same dimension angle;

Therefore, in the appearance of each net, the same position is represented on the panel 13 of the pixel at the same position.

Fig. 6 (a) m,

Then, by taking each of them, the values of the pixels at the same position are arranged to obtain the angle and size at a certain point; Fig. 6 (b) 麵,

Fig. 6 (b) shows the squarishness of the squarishness of the high-glued plating that has been formed in this manner.

In this way, any adjacent pair is detected from the angle at which the! Straightens and the angle at which the local minimum takes place in the ^!

Assuming that this angle is ex and ^, one's own formula plays ^:

ml = 2 d (n ² —s in ² ) ^1/2 ---{\)

(m-1 / 2) 1 = 2 d (n ² -s in ² β) ^{1 /}

Here, m is an arbitrary beam, is the wavelength of the surface 11, d is a difficult film, and n is the refractive index of the lens.

It should be noted that the βΐ rate n _{Q of} air is assumed to be no = 1.

From JJ's equations (1) and (2),

d = A / {4 [(n ² — sin ² a) ^1/2 ― (n ² — sin ² β) ^1/2 ]}

• · · (3)

Or

ά = λ [(n ² — sin ² a) ¹ / ^2- (n ² — sin ² β) ^1/2 ] / 4 (sin ² β — sin ² a) · · · (4)

It becomes.

Here, the refractive index n and the skin length; since it is a mouth, the film enjoyment d can be obtained by subtracting the obtained angles α and.

By reducing this operation to all points, we can obtain the 2 ^ E; distribution of

With reference to FIG. 7 to FIG. The size of the Koyodo panel 13, which will be the image, is 1800 awakens.

Omm's statement is that the resist film applied to the glass will be removed. Note that the middle C 中 Kg; i of the if ^ in the bandpass filter 18 is 义 = 589 nm, and the refractive index n of the resist film at this; 1 = 589 nm is n = 1.5572.

See Figure 7

As a device of this lKim device, 180 Ommx 150 Omm ¾H¾, 150 ° mm is obtained by using the CCD camera 12 of Xiamen to obtain the image by moving the moving stage 14 once. Cover the width and il as if it were the same. In addition, the CCD camera 12 moves from the lens 19 to the movable stage 14 with a slope of 30 ° at a height H of 440 m, and in the scanning direction, θ I = 15 ° to Θ ₂ = Makes it possible to insult the image of a junk up to 60 °.

Here, the trace of the resist film is assumed to be 200 Onm (= 2 m), and the goal is to make it possible to detect 3% of JiP bombs. Multiplier is configured to have 0.3% membrane resolving power.

Since the door of 0.3% of the yeast of 2000 nm is 6 nm, it is necessary to make it slightly higher than 3 digits.

According to equation (4), if the angle and S are sufficiently »(this mochi is generally satisfied), the angle performance is also necessary, so the required angle resolution Is set to 0.05 ° (= 3 ').

In addition, when detecting peaks and valleys by shelving the peak detection algorithm from the fiber swells obtained from the roots of the soul, the two-dimensional approximation is used to approximate the regrets of the divided sections. The sampling interval can detect peaks with high resolution.

A peak detection test was performed in advance, and when the position detection interval was set to 0.2 ° and the signal was subject to noise of ± 1% of 鯽畐, peak detection of approximately 0.05 ° or less was detected. I was despised to be accurate.

In addition, this 1% noise may cause variations in the sensitivity of each pixel, contamination of the ^ system, rn ui unevenness, and errors in standing detection accuracy such as the HE of the lens 19. The difference shall be included.

Therefore, in this dance fe ^^, it is assumed that the noise of the detection accuracy such as the noise of the CCD sensor 12 surface 11 and the distortion ダーク E of dark ¾Ε, flat i! B The detection 1 is (K 2 °).

In FIG. 7, the battle system between Δχ and ΔΘ at the approximate point on the measurement panel 13 is χ = Η-t a η 、

d / d Θ = Η / cos ² Θ

And so.

Δχ = (H / cos ² θ)…… (5)

Can be stored.

Here, in 彻て, the change of Δ 当り per ΔX The perceived silence = 15. If you try to calculate Δχ, the tfi for one pixel is ΔΘ.

Since the Δθ ^ 3. 490 X 10- ^3,

Δχ ^ (. 440/0 9330) x 3. 490 X 10 - 3

^ 1.646 [mm]

It becomes.

Therefore, it can be seen that the fiber must be at least 1.6 mmOT.

Also, using a CCD camera 12 that is 30 ° apart, like J, to pan from β¾θι = 15 ° to Θ ₂ = 60 °, the angle of view in the direction of the lens 19 ^ 2 is 60. It is important to note that the age of a 1 / 3-inch stomach CCD camera as the CCD camera 12 and the focus of the lens 19 is 4 mm.

At this time, the angle of view in the ®a direction is about 48 °, so around ^ m e, = \ 5 °,

In order to cover a width of 405 mm, and to cover a length of 1500 mm, four CCD cameras 12 may be used because 1500/405 ^ 3.7. In addition, in order to cover with a high dissociation of 1.6 mm J: in the X-direction with a CCD camera 12 that can cover the width of the 405 1. 6) b waist.

Therefore, it is only necessary to use a CCD camera 1 having a resolution of 640 X 480 or a VGA.

Next, we explain the advantage at a certain point.

As shown in FIG. 7, the movement of the moving stage 14, that is, by scanning, the point vertically dropped from the CCD camera 12 to the moving stage 14.

That is, the data of the relation between the separation and the position was machined.

Assuming Jokei of m, and the mouth of ± 1% of the random noise in the data, it was further rolled into 8b it, and L from the origin 0 in FIG. 7, Hanmisun; ¹ «fabric 8乃Te, shown as 10 〖, was questioned for a hawk.

See Figure 8 to Figure 10

When peak detection was applied to this data sequence, the first value was L = 253.49, and the value was L = 253.49 (^ standing, first Kanyanagi L = 408.43 Was detected.

Here, assuming that the point Pi (D m Θ I, the height of the CCD camera 12 is H from 〇 to Oki L,

t an (L / H)

Since H = 440 NOTE, the value of H in the first bad value is

a = t an- ¹ (253.49 / 440)

t an- ¹ (0, 5761 136)

^ 29. 95 °

It becomes.

On the other hand, S 确 in the first sub vice is = tan ^→ (408.43 / 440)

tan- ¹ (0.992825)

^ 42. 87 °

It becomes.

Obtained by lack

A together with nm¾t n = l. 5572 and JJ's equation (4),

d ^ 1986 nm

The value of 00-Onm was 0.7% [= (2000-19 86) / 2000 = 14/2000].

Next, with reference to FIG. 11, the method of finding the wisteria at the H ^ point in the middle 漳 is translated.

See Fig. 11

As shown in FIG. 11, when the point of the lens 19 lowered vertically from the to the moving stage 14 is 0, and the line that makes the point 0 by scanning the moving stage 14 is the center, the point P _{2 of the}孭 ij image is obtained. The point P ₂ 'where the was lowered to the middle line from and. Is L, and P from P ₂ to 龥 is W.

Note that the direction toward the left is the plus direction of W, while the direction toward the left is the direction toward the back.

Also in this case, the height H of the CCD camera 12 is similarly set to H = 44 Omm, and at point P ₂ of the standing position of d = l 5 Omm, the thickness of the resist film is determined to be 210 Onm, and the size is as follows: I've got the data of the boat and the position.

Assuming that Jt ^ is also the brother of H, the random noise of ± 1% was applied over the course of the night, and then rounded to 8 bits, as shown in Figs. 12 to 1. The data was one.

In addition, the foot L in FIG. 12 shows the foot from the request 0 to the point D on the center line.

Fig. 12 Nota 14 Fiber

When peak detection was applied to the obtained data sequence, the first value was L = 370.21 The position of the marauder, the first 麵 N (directly, L = 203.67 was detected to be awake.

Where the point p ₂ (wm ei ^

θ = ϊ an— ¹ (LH)

Here, L '= (L ² + W ² ) ^1/2 and H = 44 Omm, so that the visual perception at the first g ^: value is

a = t an ^-1 (399.44 / 440)

an " ¹ (0.90783)

^ 42. 23 °

It becomes.

On the other hand, at the first pole W,

tan- ¹ (252.95 / 440)

tem- ¹ (0.557488)

^ 29. 89 °

It becomes.

Then, the obtained α

nrn ^^ n ^ 1. With 5572, ± |

d ^ 2088nm

The thought: 呉 1 ¥, 210 Onm, said Wu Hui was 0.6% [= (2100—20 88) / 2000 = 12/2000].

By translating such difficulties into all points P, the distribution of the wisteria in the resist film across the panel can be as accurate as 3% in Jiangsu.

& ±,

Not limited to the configuration informed by this translation, various types are possible.

For example, at the foot of ± 1 ff, the CCD type area sensor is used as the ¾ position, but for CMOS applications, a MOS type area sensor may be used. In addition, the angle of the camera, the height of the camera, and the view that captures the response of the camera, which is reflected in the fiber of the camera, are determined by the angle of the camera and the numerical aperture of the lens. It goes without saying that it is capable.

Also, at the foot of one's own difficulty, I got ^! From the intensities of sunlight, a pair of concubines, 妾 W and W, are used to seek help, but are not limited to such males. It is also acceptable to set the value set to »S (obtain and take the average of 11 ¥ calculated from each set. By using this male, it is possible to suppress the variation it can.

On the other hand, it is possible to fit not only the MP but also the gradual rate “^” and “fitness” by fitting the «humiliated by labor rules and the angle at first glance to the shank. Yes, according to the purpose of ^ Ht ^ and 髓, make sure to select the best journey.

In addition, in the difficult fiber, the acquisition of J3 richness of the resist film in ¾B¾ ^ nel is described as τ¾, but it is not limited to the resist film, but it is converted to 1 ¥ of various thin films. It is good if it is intercept or half-way with respect to the original wavelength. For example, the l & W β process to be provided on the light exit surface of the light guide plate in the backlight of the sidelight ¾ or the frontlight of the sidelight type 〖This is also flipped.

In addition, the present invention is not limited to the above-described method, but may be applied to j¾tr in other locations of plasma concentration or various processes in difficult processes of various devices of Kasumoto Sokki. It is something that is turned over.

Further, the present invention is not limited to the application of the separating device, but is applicable to all j steps which have difficulty in the order of micron to sub-micron in surface force.

According to the present invention, since the western elephant of the awakening is acquired collectively using an area sensor type image sensor such as a CCD camera, the measurement can be performed in a rich and elaborate manner. , Etc. It is easy to do, and as a result, ¾®ft¾ ^ 袭氐 Cost reduction 'が It greatly contributes to Ganjiro.

Claims

The scope of the claims

1. The singularity impinges on the light from one of the originals that has been converted to a monochromatic color by a filter. | J¾¾ ^ , While changing the dimension of the self-illuminated light to a step angle, visualized by the device, and measured the maximum value and maximum J of the 寸 ^ §degree of the measured light. Take a value, and get the 纖 ¥ of Ryu Fiber from the ^ dimensions of the irradiation light.

2. JJ¾ ^ by performing the fitting of the stray light of the stray light and the pre-acquired light of the reflected light.

3. Use an area sensor type image sensor as the ± 1

Claim 1 or 2 m <mmL ₀

4. Set up ± ι self-contrast and set the distance corresponding to one pixel of ± 1 self-image sensor.

Claim 3

5. ± 1 己己赚赚赚取得取得!! 内内内.. 内内.............. .. Self-imaging—the amount of energy at the same position corresponding to one pixel of the image sensor; the distribution of ± | ¾11 ϋ ¥ from the return system of degrees;