CN101078107B - Insulation multilayer thin film manufacturing device - Google Patents

Abstract

To provide a method of controlling film thickness of dielectric multilayer film, such as optical thin film, with high precision, an optical film thickness controlling apparatus and a dielectric multilayer film manufacturing apparatus that can control the film thickness based on the same method, and dielectric multilayer film manufactured using the controlling apparatus or manufacturing apparatus. An optical film thickness controlling apparatus includes a film formation device 15 having a rotatable substrate 23 and a sputtering target 28, a photodiode 16 that detects each of a plurality of monochromatic light beams applied to the rotatable substrate along a radius thereof at predetermined intervals, and an A/D converter 17, in which a movable shutter 29 that moves along the direction of the radius of the rotatable substrate 23 to shut off film formation on the substrate 23 is provided between the substrate 23 and the target 28. From each of the monochromatic light beams detected by the photodiode 16 and the A/D converter 17, a quadratic regression function of reciprocal transmittance is calculated by a least squares method, and a CPU 18 and a motor driver 19, which indicate motion of the movable shutter based on each predicted value of the film growing time when the latest surface layer film reaches to predetermined optical film thickness, move the movable shutter 29 to shut off the film formation at the film formation region where the predetermined optical film thickness is reached to.

Description

The insulation multilayer film manufacturing installation

It is 03108229.7 that the application of this division is based on application number, and the applying date is on 03 25th, 2003, and denomination of invention is the dividing an application of Chinese patent application of " optical film thickness control method and device, insulation multilayer film and manufacturing installation ".

Technical field

The present invention relates to the method for the film thickness of control optical thin film when forming film, specifically, relate to according to optical technology, be used to carry out the device of the control film thickness of this method, and make main as optical thin film and can be during forming with the device of the insulation multilayer film of high precision control thickness.Optical thin film is widespread use in various opticses or element, as waveguide, diffraction grating, optical transmitting set, telltale, optical memory and solar cell.Specifically, with regard to the optical thin film of the dense wave division multipurpose equipment of the communication technical field that is used for relating to optical communication, the trend of using multilayer film to make is more and more obvious.Correspondingly, the optical film thickness with each layer film in the high precision control multilayer optical film structure has become extremely important.

Background technology

Film thickness at the rise period of film measurements film is extremely important for control sedimentation rate and film thickness.With regard to optical thin film, be used for determining that the optical film thickness (product of specific refractory power and physics film thickness) of the optical properties such as reflectivity and transmissivity is more useful than physics film thickness.Therefore, monitor optical film thickness widely, its way is according to a kind of so-called optical film thickness control method of optical properties of the MEASUREMENTS OF THIN optical properties at the rise period of film measurements film.Optical film thickness control method comprises monochromatic photometry, two look photometries and multicolour photometry method.In these optical film thickness control methods, the simplest is monochromatic photometry.

Monochromatic photometry relates to use and reaches λ/4 (λ: the peak value that occurs during the monochromatic wavelength of incident) integral multiple (and the lowest point, hereinafter, each value all is equivalent to maximum value and minimum value respectively) at the optical film thickness of the film that is forming.If the optical film thickness of adjacent layers of having piled up substrate one side of the up-to-date upper layer film that is forming at its coated surface after beginning to increase when the optical film thickness of the film that is forming reaches the integral multiple of λ/4 first is not equal to the integral multiple of λ/4, can not show that such peak value does not always occur with the mathematics real number if perhaps comprise the admittance (admittance) of the system of adjacent layers.Yet under this type of situation, in case peak value occurs, it will regularly occur in the growth cycle of optical film thickness, and is consistent with the integral multiple of λ/4.

Yet, in monochromatic photometry, above-mentionedly relate to the decline that to avoid control accuracy to a certain degree on traditional methodological principle that the peak value that use to occur carries out peak value control, because change very little with respect to the raising of optical film thickness in the contiguous place of peak value light intensity.

Can improve accuracy by using interference filter, the wavelength of this interference filter forms the terminated wavelength somewhat different than a point control film that is used for outside the contiguous place of the peak value of light intensity noticeable change.As such method, can measure light intensity (transmissivity (reciprocal transmittance)) as a kind of optical properties, to select a kind of optical phase angular region that the height control accuracy that increases optical film thickness is provided, thereby determine that film forms termination time point (for example, referring to patent documents 1).

On the other hand, in the technology of patent documents 2, for example, use traditional monochromatic photometry by the wavelength that uses expection.According to this method, the data set that just forms the tight measurement that obtains previously of a peak value in the growth of the integral multiple of λ/4 of light intensity (transmissivity) the response optical film thickness of measuring revert to quadratic function by method of least squares.The time point of peak value that can form regression function is predicted, forms the termination time correspondingly to determine film.In the preferred case, the time be the prediction point itself, but if the consideration specified conditions, the point of reference prediction comes judgement time as the time point basis.

Patent documents 1:Japanese Patent Laid-Open No.S58-140605 (the 2nd to 3 page, Fig. 1)

Patent documents 2:Japanese Patent Laid-Open Ne.S63-28862 (the 2nd to 6 page, Fig. 1 and 2)

Summary of the invention

As indicated above, form the demand with multiwalled optical thin film in the communications field more and more vigorous.Specifically, the multilayer optical film in the dense wave division multipurpose equipment (for example, bandpass filter) may comprise the number of plies more than 100 or 100.Can form multilayered structure with alternating layer, comprise the layer of high refractive index and the layer of low-refraction, each layer all has the optical film thickness of the odd-multiple that equals λ/4 (for bandpass filter, can form a cavity layer by high refractive index layer or low-index layer, between alternating layer, have the optical film thickness of the even-multiple of λ/4).In this case, the usual way that relates to the film thickness by replacing each layer film in the watch-dog substrate control multilayered structure related with it is unpractical, because the processing of needs becomes very complicated.

So, the multilayered structure that comprises the many alternating layers that are similar to product film can be piled up on the watch-dog substrate, and can correspondingly monitor multilayered structure.Yet in this case, along with increasing of the number of plies of piling up, the reflectivity of the multilayered structure of growth improves, that is, its transmissivity progressively reduces, and so the reliability of the value of measuring also reduces.Therefore, if carry out above-described function regression, the observed value that function curve is drawn transmissivity is left at the contiguous place of the peak value in the quadratic regression function, and specifically, so, its association becomes lower.Therefore, film thickness is difficult to be controlled with high precision.In addition, aspect accuracy, also have a problem, promptly all in the multilayered structure that will monitor on the watch-dog substrate constitute the duplicating accurately of each layer whether film can be product film.

Therefore, with regard to having the multiwalled optical thin film, film thickness is controlled by direct method for monitoring usually, monitors many alternating layers itself of piling up on the product substrate in the method.Fig. 1 has shown the example of the film thickness control device of direct method for monitoring.Shown in Fig. 1 (a), electron beam gun 2 and ion gun 3 are placed side by side, in the face of the rotatable substrate 4 in the vacuum chamber 1, optical transmitting set 5 is positioned over rotatable substrate 4 opposites, outside of chamber 1, the light that optical transmitting set 5 is launched passes down logical light window 6 and last logical light window 7 along the turning axle 4a of rotatable substrate 4, and is received by the optical receiver 8 that is positioned at 1 outside, chamber.In the film thickness control according to this device, product substrate 4 is by CD-ROM drive motor 9 rotations, and the supervision monochromatic ray flux from optical transmitting set 5 passes down logical light window 6 along turning axle 4a.In this state, dimmer (shutter) 2a opens, to form the film of piling up on product substrate 4 by electron beam gun 2.At this moment, optical receiver 8 detects the variation of the light intensity that produces owing to the interference by following logical light window 6 and last logical light window 7.Then, control the film thickness of the build-up film that is forming based on the variation of light intensity.That is, judge that according to the film thickness control method of describing in patent documents 1 or 2 film forms the termination time point.Then, close the film formation process that uses electron beam gun 2, to stop increasing of film thickness by dimmer 2a.So, near the center of product substrate, produce insulation multilayer film with satisfied spectral response curve.

Yet still in this case, along with increasing of the number of plies of piling up, the reflectivity of the multilayered structure of growth improves, that is, its transmissivity progressively reduces, and the reliability of observed value also reduces, and this will cause the shortcoming identical with the situation of watch-dog substrate.This influence is serious, particularly in the narrow band filter made from a large amount of alternating layer that comprises high refractive index film λ/4 and low refractive index film λ/4.In addition, along with the quantity of the alternating layer of piling up increases, even near peak value and the lowest point, the curve of the intensity variation of an expression emission that departs from the quadratic regression function will be drawn, this light intensity changes along with the increase of film thickness, and film thickness becomes and is difficult to be controlled with high precision.Fig. 2 has shown fractureing of quadratic regression function.When the light intensity of emission reduces (, high refractive index layer H on the low-index layer L is up-to-date upper layer), and when the light intensity of emission increases (, high refractive index layer H on the high refractive index layer H is up-to-date upper layer), the peak value of quadratic function regression forecasting becomes significantly different with the position, the lowest point, and this causes serious dispensing error.Therefore, have such problem: when the light intensity of emission reduced, the film of prediction formed the termination time point too early, and when the light intensity of emission increased, the film of prediction formed the termination time point too late.

In view of this type of problem, an object of the present invention is to provide a kind of method of controlling the film thickness of the insulation multilayer film such as optical thin film with high precision, can control the optical film thickness control device of film thickness based on Same Way, with the insulation multilayer film manufacturing installation with use this control device or insulation multilayer film that manufacturing installation is made.

In order to reach this purpose, according to the present invention, in the period that forms the single or multiple lift optical thin film, incident monochromatic ray (wavelength X) is by the single or multiple lift structural transmission, measure the transmissivity of optical thin film, the inverse of transmissivity suitably is defined as down transmissivity.

Here, from the final condition (that is, each the tangential component B or the C in electric field or magnetic field are respectively successive) of structure, use the eigenmatrix of single thin film, by the admittance C/B of following formula (1) expression system.

[formula 1]

$\left[\begin{array}{c}B\\ C\end{array}\right]=\left[\begin{array}{cc}\cos \mathrm{\θ}& i/N\sin \mathrm{\θ}\\ \mathrm{iN}\sin \mathrm{\θ}& \cos \mathrm{\θ}\end{array}\right]\left[\begin{array}{c}1\\ Y\end{array}\right]...\left(1\right)$

In this formula, N represents the specific refractory power of single thin film, and θ represents the phase differential between the different interfaces on the single thin film, and Y represents the transmission power of substrate system.

The transmissivity T of single thin film is expressed by following formula (2), and wherein symbol * represents hetero conjugation.

T＝4Y/(B+C)(B+C)＊...(2)

Therefore, derive following formula (3) from formula (1) and (2).

T＝4Y/[(1+Y) ²+{(Y/N+N) ²-(1+Y) ²}sin ²θ]...(3)

Here, the specific refractory power of supposing air or vacuum is 1.

In addition, in the present invention, optical phase angle θ is expressed by following formula (4), relates to monochromatic wavelength X and the optical film thickness Nd (N represents the specific refractory power of film, and d represents the physical thickness of film) of the upper layer film of the up-to-date growth of piling up.

θ＝2πNd/λ...(4)

In addition, for method of least squares, the data set of the measurement of two variablees, promptly, the film rise time (t) of the upper layer film related and the transmissivity (1/T) of falling with the increase of optical film thickness, reach maximum value or minimum value so that before the quadratic regression function of following formula (5) is provided at the data set of measuring, revert to quadratic function, wherein A ₀And B ₀Be constant, t _pBe illustrated in when reaching maximum value or minimum value film rise time.

1/T＝A ₀+B ₀(t-t _p) ²...(5)

In order to reach the higher association of regression function, expectation is to reaching the λ/4 (λ: the data set execution function regression of the measurement of sampling after last about time point of film thickness monochromatic wavelength) and this time point that equals maximum value or minimum value at 25 to 10% o'clock at the optical film thickness near the upper layer film of the maximum value of function curve or minimum value.

Formula (3) is transformed into following formula (6) simultaneously,

1/T＝(1+y) ²/4Y+{(Y/N+N) ²-(1+Y) ²}sin ²θ/4Y...(6)

The transmissivity T of the up-to-date upper layer film at the time point place when the growth of up-to-date upper layer film begins ₀, and the transmissivity T of the up-to-date upper layer at the time point place when its optical film thickness reaches λ/4 ₉₀Express by following formula (7) and (8) respectively.

T ₀＝4Y/(1+Y) ²...(7)

T ₉₀＝4Y/(Y/N+N) ²...(8)

If admittance Y is a real number, will go out following formula (9) from these derivations of equation so.

(1/T ₀-1/T)/(1/T ₀-1/T ₉₀)＝sin ²θ...(9)

So, transmissivity can be expressed as only depending on the function at optical phase angle.

Based on above-described interference theory, the transmissivity of falling distributes every the gap periods ground of 1/4 the optical film thickness that is equivalent to monochromatic wavelength, fall the maximum value of transmissivity and minimum value near, (θ is as variable, sin for the function of transmissivity of falling of being derived out by formula (9) expanded formula ²θ also relates to this function) can be similar to quadratic function.Therefore, as the predictor of film rise time when obtaining maximum or minimum optical film thickness, can use the film rise time of quadratic regression function when maximum value or minimum value.Form by film, can control optical film thickness to being equivalent to 1/4 of monochromatic wavelength at predicted time termination table surface layer film.

Such optical film thickness control method is simple, because the optical properties of the whole multilayered structure identical with the structure of film product can once measure, and correspondingly carries out peak value control.In addition, return and carry out because peak value prediction is based on high related quadratic function, so film thickness can be controlled with high precision.

In this case, the optical film thickness of upper layer film can come out based on the function calculation of transmissivity of being derived out by formula as indicated above (9) expanded formula.Therefore, can be by the rise time of prediction upper layer film when reaching the target value of optical film thickness with up-to-date upper layer depositing of thin film speed, optical film thickness is controlled to the value of expection, and sedimentation rate can suitably define with its time differential and its time difference.That is, the optical film thickness that control is not limited to be equivalent to 1/4 thickness of monochromatic wavelength, but can predict any optical film thickness.

In addition, owing to, can carry out the in-situ measurement of product film along with the incidental transmissivity of the formation of optical thin film is measured on the product substrate, that is, and the direct method for monitoring of the optical film thickness of up-to-date upper layer film.So, this optical film thickness control method is further being improved aspect treating processes and its accuracy.

In order to carry out above-described optical film thickness control method, a kind of optical film thickness control device is provided, this device comprises film former, this equipment has rotatable substrate and thin-film material source, they both toward each other, and a kind of photoelectric conversion device, be used to detect the many homogeneous beams that are applied to rotatable substrate with predetermined interval along radius, between substrate and thin-film material source, provide movably dimmer, it moves along the direction of the radius of rotatable substrate, forms with the film of closing on the substrate.Being designed to make movably the dimmer response controller of optical film thickness control device and moving, controller indicate the action of dimmer based on each predictor of film rise time of the homogeneous beam prediction that detects with photoelectric conversion device.So, can be according to the film rise time of above-described optical film thickness control method prediction upper layer film when reaching the optical film thickness of plan.On the upper layer film, film formation process termination in film has risen to the zone of optical film thickness of plan, and such termination of film formation process is carried out continuously.So, can control film thickness, so that film thickness can distribute equably with high precision.

In addition, on current optical communication market, the narrow band filter that is used for the multiplexer/demultiplexer of dwdm system requires one group by definite various of ITU-T (Union Internationale des Telecommunications-telecommunication standardization sector), for example, 4,8,16, ..., 128 centre wavelength and the bandpass filter that designs.So, needing simultaneously and make in large quantities with various wavelength is the wave filter at center.

Yet, in multilayer film manufacturing installation shown in Figure 1, monitor that the monochromatic ray flux only passes along rotary middle spindle.Therefore, effective in the direct method for monitoring central zone that only reference numerals in Fig. 1 (b) 10 is represented.The optical thin film product that provides in the area away from the center of substrate of reference numerals 11 expression; because the fluctuation that evaporation distributes; the difference of the relative distance between product substrate and the evaporation source; the non-uniform temperature of product substrate surface or the like; wavelength attribute or the like changes through regular meeting; therefore, the attribute of the supervision wavelength that uses in direct method for monitoring is unsatisfactory.

Therefore, the position of the applied supervision monochromatic ray flux that passes substrate may from rotary middle spindle transfer on the concentrically ringed circumference in the rotation area certain a bit, can be in the annular zone shape area that forms along circumference as the effective area of direct method for monitoring.Yet in this case, effectively region area can only obtain slight improvement.Pass the zone of substrate at the supervision monochromatic ray flux of direct method for monitoring, even when the film thickness of the layer that just in time formed before up-to-date upper layer is controlled with lower accuracy, if the time point that the termination film of following up-to-date upper layer forms can just in time be controlled at peak value and the lowest point, error is repaired naturally, and error also can correspondingly reduce.Therefore, in order to obtain high-quality optical thin film product, owing to can bring significant advantage to monitor area, it is very important amplifying this zone.

Therefore, vacuum chamber according to an insulation multilayer film manufacturing installation of the present invention has thin-film material source and reaction source, each source is all placed side by side to face rotatable substrate, an insulation multilayer film manufacturing installation comprises: the film deposition rate function unit, it has an opening, is used for providing along the radius of rotation substrate circumference the film deposition rate of the insulation multilayer film that a gradient forms to the said rotatable substrate; Film thickness is corrected parts, is used to correct the film thickness of the insulation multilayer film that forms on the said rotatable substrate, and this film deposition rate function unit and film thickness are corrected parts and provided between rotatable substrate and thin-film material source; The luminous intensity measurement device is used to measure the monochromatic intensity of supervision of passing a plurality of monitoring points along the radius of said rotatable substrate; And Controlling System, be used for with the supervision monochromatic ray flux of arranging at least two wavelength along the order that increases progressively or fall progressively of the wavelength of the monochromatic ray flux of the location association in the monitoring point of said radius, so that optical throughput passes corresponding monitoring point, and can respond and move said film thickness by the variation of the light intensity of said luminous intensity measurement measurement device and correct parts.

In this device, the monochromatic ray flux is to arrange with the order that increases progressively or fall progressively along the wavelength of the location association in the monitoring point of radius, so that the supervision monochromatic ray flux of different wave length passes corresponding monitoring point.

Here, the value of nd/ λ is arranged with ascending order, and wherein λ is the supervision wavelength that passes the supervision monochromatic ray flux in the monitoring point on the rotatable substrate, and the monitoring point is to arrange to inside circumference along radius from the neighboring of substrate.Monitoring under the situation that the monochromatic ray flux is arranged by this way, when the light intensity of the increase of the film thickness of the up-to-date upper layer that depends on insulation multilayer film is detected by the luminous intensity measurement device, the gradient of the film deposition rate that is caused by the opening of film deposition rate function unit reduces from the neighboring to the inside circumference along the radius of rotation substrate circumference, and the monitoring point of the neighboring of the rotation substrate circumference of short supervision wavelength forms peak value earlier distributed to it.Therefore, the increase of the film thickness of insulation multilayer film can be corrected parts with film thickness and moves to inside circumference from the neighboring of rotation substrate circumference and corrected by responding this situation.That is, the film thickness of the up-to-date upper layer film of insulation multilayer film can be controlled by high precision.In addition, because the monochromatic ray of at least one wavelength can be made insulation multilayer film by the direct method for monitoring control film thickness with various supervision wavelength as monitoring optical throughput.

The travel direction that above-described film thickness is corrected parts not necessarily only limits to from the neighboring of rotation substrate circumference to the direction of inside circumference.The value of nd/ λ is to arrange like this, so that λ from long wavelength to short wavelength change, promptly, arrange with the order that falls progressively, wherein λ is the supervision wavelength that passes the supervision monochromatic ray flux in the monitoring point on the rotatable substrate, and the monitoring point is to arrange to inside circumference along radius from the neighboring of substrate simultaneously.In this case, when the light intensity of the film thickness of the up-to-date upper layer that depends on insulation multilayer film is detected by the luminous intensity measurement device, the gradient of the film deposition rate that the opening of film deposition rate function unit causes increases from the neighboring to the inside circumference along the radius of rotation substrate circumference, and the monitoring point of the inside circumference of the rotation substrate circumference of short supervision wavelength forms peak value earlier distributed to it.Therefore, the ununiformity of the film thickness of insulation multilayer film can be corrected parts with film thickness and moves to the neighboring from the inside circumference of rotation substrate circumference and corrected by responding this situation.

Movably dimmer is corrected parts as film thickness on the direction of the radius of said rotatable substrate, is closed in film formation process rotatable substrate on along radius with the above-described order that increases progressively or fall progressively by moving dimmer movably.

Correspondingly, for the insulation multilayer film of the monochromatic equal in quality that forms with annular zone shape of each of the different wave length that obtains to pass the monitoring point, can under identical condition, close film formation process.Therefore, can produce various high-quality insulation multilayer films on a large scale, they obtain from annular zone shape monitor area.

In addition, Controlling System by the insulation multilayer film manufacturing installation, variation by the light intensity of luminous intensity measurement measurement device, be when the every bit that passes in the formation period of the insulation multilayer film of supervision monochromatic ray flux on rotatable substrate that comprises at least one wavelength in a plurality of monitoring points at first as the measure of the change of transmissivity, the inverse of transmissivity suitably is defined as down transmissivity.

Based on above-described interference theory, the transmissivity of falling distributes every the gap periods ground of 1/4 the optical film thickness that is equivalent to monochromatic wavelength, fall the maximum value of transmissivity and minimum value near, derive out by formula (9) expanded formula fall transmissivity function (depend on variable θ with sin ²The function of 0 expression) can be similar to quadratic function.Therefore, the predicted time of up-to-date upper layer film when reaching maximum or minimum optical film thickness can use the film rise time of quadratic regression function when maximum value or minimum value.The time that the film of upper layer film is formed on prediction stops.In this process, return and carry out because peak value control is based on high related quadratic function, the control accuracy that therefore reaches 1/4 the optical film thickness that is equivalent to monochromatic wavelength is further improved.

In this case, the optical film thickness of upper layer film can come out based on the function calculation of transmissivity of being derived out by the expanded formula of formula as indicated above (9).Therefore, the film deposition rate that time diffusion or time difference can be used as up-to-date upper layer film calculates, can the based thin film sedimentation rate time of the up-to-date upper layer film of prediction when reaching predetermined optical film thickness.So, can predict and control the optical film thickness of expection.That is, the optical film thickness that control is not limited to be equivalent to 1/4 thickness of monochromatic wavelength, but can control any optical film thickness.

In addition, alternatives as above-described manufacturing installation, another kind of insulation multilayer film manufacturing installation according to the present invention has a vacuum chamber that is used to make, this vacuum chamber has thin-film material source and reaction source, each source is all placed side by side to face rotatable substrate, and comprise: the film deposition rate function unit, it has an opening, is used to control the film deposition rate of the insulation multilayer film that forms on the said rotatable substrate; Film thickness is corrected parts, it has an opening, be used to correct the film thickness of the insulation multilayer film that forms on the said rotatable substrate, film deposition rate function unit and film thickness are corrected parts and are provided between said rotatable substrate and said thin-film material source; The luminous intensity measurement device is used to measure the monochromatic intensity of supervision of passing many monitoring points along the radius of said rotatable substrate; And a Controlling System, the variation that is used for responding the light intensity of said luminous intensity measurement measurement device when each of one or more wavelength monitors that monochromatic ray flux passes said monitoring point comes partly to start independently the opening that said film thickness is corrected parts.

By this device, the light intensity of increase of film thickness that depends on the up-to-date upper layer of insulation multilayer film is detected by the luminous intensity measurement device, the opening response light intensity that film thickness is corrected parts opens or closes, thereby can correct the increase of the film thickness of insulation multilayer film.That is, the film thickness of the up-to-date upper layer film of insulation multilayer film can be controlled with high precision.In addition, in this process, because the monochromatic ray of at least one wavelength can be made insulation multilayer film by the direct method for monitoring control film thickness with various supervision wavelength as monitoring optical throughput.

Correct the Controlling System of parts as partly and independently opening or closing film thickness; use the separate type dimmer; they open or close the arc area that forms along concentrically ringed circumference independently, and this circumference is to be drawn by the trace in each monitoring point when rotatable substrate rotates.

Correspondingly, for the insulation multilayer film of each the monochromatic ray flux in the different wave length that obtains to pass the monitoring point, can under identical condition, close film formation process with the equal in quality of each arcuate shape shape.Therefore, can produce various high-quality insulation multilayer films on a large scale, they obtain from the arc monitor area.

In addition, Controlling System by the insulation multilayer film manufacturing installation, variation by the light intensity of luminous intensity measurement measurement device, be when the every bit that passes in the formation period of the insulation multilayer film of supervision monochromatic ray flux on rotatable substrate that comprises at least one wavelength in many monitoring points at first as the measure of the change of transmissivity, the inverse of transmissivity suitably is defined as down transmissivity.

Based on above-described interference theory, the transmissivity of falling distributes every the gap periods ground of 1/4 the optical film thickness that is equivalent to monochromatic wavelength, fall the maximum value of transmissivity and minimum value near, derive out by formula (9) expanded formula fall transmissivity function (depend on variable θ with sin ²The function that θ represents) can be similar to quadratic function.Therefore, the predicted time of up-to-date upper layer film when reaching maximum or minimum optical film thickness can use the film rise time of quadratic regression function when maximum value or minimum value.The time that the film of upper layer film is formed on prediction stops.In this process, return and carry out because peak value control is based on high related quadratic function, the control accuracy that therefore reaches 1/4 the optical film thickness that is equivalent to monochromatic wavelength is further improved.

In this case, the optical film thickness of upper layer film can come out based on the function calculation of transmissivity of being derived out by the expanded formula of formula as indicated above (9).Therefore, by detecting the predetermined optical film thickness that up-to-date upper layer film reaches, film thickness can be controlled to the optical film thickness of expection.That is, the optical film thickness that control is not limited to be equivalent to 1/4 thickness of monochromatic wavelength, but can control any optical film thickness.

In two insulation multilayer film manufacturing installations, the splash target of at least two different materials that provide for any target can be selected forms the source as film.So, can select the set goal material as the stratified material of each structure in the insulation multilayer film, therefore, the multilayer film manufacturing also is improved.

When metal Ta and metal Si are used as the different material of splash target, can make such as Ta ₂O ₅The tantalum laminated film of film and so on (it is the common high refractive index layer that comprises the optical thin film product of BPF) and such as SiO ₂The silicon laminated film of film and so on (it is the common low-index layer of optical thin film product).

When reaction source sent reactive neutral radical gas, when laminated film as indicated above formed on the upper layer film, the raising of substrate temperature was suppressed.As a result, the decline of the accuracy of control optical film thickness is inhibited.

In addition, use the insulation multilayer film of above-described optical film thickness control device or the manufacturing of insulation multilayer film manufacturing installation can have the optical film thickness of accurate control, therefore, it is suitable for optical thin film and uses.

Description of drawings

Fig. 1 (a) is the constructed profile that is used for traditional insulation multilayer film manufacturing installation of direct method for monitoring;

Fig. 1 (b) is the principle chart that is presented at the optical properties district on the substrate that uses in the manufacturing installation shown in Fig. 1 (a);

Fig. 2 is the deviation that shows according to the quadratic regression function of traditional optical film thickness control method;

Fig. 3 has summarily shown according to optical film thickness control device of the present invention;

Fig. 4 is an optical signalling measurement pattern, has shown to work as by Ta ₂O ₅The value of transmissivity of 8 passages of the light that photorectifier detected when the single thin film of making formed by using optical film thickness control device shown in Figure 3;

Fig. 5 is a figure that shows the related and predicted time when reaching the peak value of optical signalling between each optical signalling among Fig. 4, and this figure revert to a cubic function;

Fig. 6 (a) is the constructed profile according to insulation multilayer film manufacturing installation of the present invention;

Fig. 6 (b) is the top view of the substrate in the manufacturing installation that shows among Fig. 6 (a) and the position in monitoring point;

Fig. 6 (c) is the top view of the manufacturing installation shown in Fig. 6 (a);

Fig. 7 (a) is the constructed profile according to insulation multilayer film manufacturing installation of the present invention;

Fig. 7 (b) is presented at the substrate in the manufacturing installation shown in Fig. 7 (a) and the top view of separate type (split) dimmer;

Fig. 7 (c) is the top view of the manufacturing installation shown in Fig. 7 (a);

Fig. 8 be in the example 2 by Ta ₂O ₅Film (H) and SiO ₂Accuracy figure relatively between the quadratic function of the quadratic function recurrence of the transmissivity of the multilayer film that film (L) constitutes and the transmissivity of multilayer film returns;

Fig. 9 be make in the example 3 by Ta ₂O ₅Accuracy figure relatively between the quadratic function of the quadratic function recurrence of the transmissivity of the single thin film that film constitutes and the transmissivity of single thin film returns based on the scope of recurrence;

Figure 10 has shown the frequency spectrum of the bandpass filter of making in the example 4;

Figure 11 is the principle chart that the optical properties zone on the substrate that provides in the example 5 is provided;

Figure 12 is the figure that has shown the startup of the movably dimmer in the example 5;

Figure 13 is the figure that the spectral-transmission favtor attribute of the middle band bandpass filter that provides in the example 5 has been provided;

Figure 14 is the figure that the spectral-transmission favtor attribute of the narrow band filter that provides in the example 6 has been provided;

Figure 15 is the figure that the spectral reflectivity attribute of the anti-reflection film that provides in the example 7 is provided;

Figure 16 is the principle chart that the optical properties zone on the substrate that provides in the example 8 is provided;

Figure 17 is the figure that the spectral-transmission favtor attribute of the middle band bandpass filter that provides in the example 8 has been provided;

Figure 18 is the figure that the spectral-transmission favtor attribute of the narrow band filter that provides in the example 9 has been provided; And

Figure 19 is the figure that the spectral reflectivity attribute of the anti-reflection film that provides in the example 10 is provided.

Embodiment

Fig. 3 summary has shown the optical film thickness control device of carrying out according to optical film thickness control method of the present invention.The optical film thickness control device comprises adjustable laser source 12,8 branch optical fiber coupling mechanisms 13,8 line (throw) optical fiber collimators 14, splash film former 15,8 linear light electric diodes, 16, the 8 passage A/D converters of being made by InGaAs 17, CPU18 and the linear motor driven device 19 that is used to carry out data processing.

Adjustable laser source 12 is connected with fiber coupler 13 by single mode fiber optic cable 20, and fiber coupler 13 is connected with fiber collimator 14 by single mode fiber optic cable 21.Come the light of self-excitation light source 12 to be divided into eight light beams by fiber coupler 13.Then, optical fiber collimator 14 makes eight light beams parallel to each other, and then, transparent window 22 and rotatable substrate 23 that light beam passes splash film former 15 arrive photorectifier 16.The CPU18 and the linear motor driven device 19 that are used to carry out data processing are connected to each other by the output/input interface such as RS232C 31.

Splashing device 15 has the venting port 25 that is connected to vacuum pump (demonstration in the drawings).In splashing device, the turning axle 27 rotatable substrate of supporting 23 and the target 28 that is installed on the splash negative electrode (not shown) that are driven by the driving mechanism 26 that rotates are disposed opposite to each other.Movably dimmer 29 is provided between rotatable substrate 23 and target 28, and it can move on the radial direction of substrate 23.This dimmer 29 that is inserted between substrate 23 and the target 28 can make the film formation process on the substrate 23 cut out.Movably the motion response of dimmer 29 externally is subjected to the control of linear motor 30 from the indication of linear motor driven device 19.

When carrying out the membrane according to the invention gauge control by use film thickness control device, the vacuum pump (not shown) that is connected to venting port 25 at first is activated, so that splash film former 15 is activated.Then, adjustable laser source 12 is activated, to shine rotatable substrate 23 with above-described eight collimated beams.In this state, equipment 15 starts the splash film and forms.Here, this time point is defined as the starting point of the film formation time of film.

Each of having passed in eight collimated beams of substrate 23 is all converted to voltage signal by photorectifier 16.Voltage signal is converted to numerary signal by A/D converter 17.Numerary signal is imported into the CPU18 that is used to carry out data processing, and there, signal is revert to a quadratic function, and this function has a field of definition, and this field of definition is equivalent to 70% to 90% of film formation time based on formula (5).

Fig. 4 has shown the curve of transmissivity of eight optical signallings that photorectifier 16 detects.As can be seen from Figure 4, suppose that the collimated beam that is applied to substrate 23 has been distributed successive numbering (1 to 8) by photorectifier 16 based on their corresponding sensed positions, promptly, on the direction of the radius of substrate 23 from outside to inside, the time point when having formed 80% film after about 120 seconds eight collimated beams reach peak value (maximum value) in proper order with this.Here, falling transmittance graph reaches the time point that film that the time point of peak value can be regarded as forming has the optical film thickness of expection.

Fig. 5 is the figure of the relation between a sensed position that has shown collimated beam 1 to 8 and the prediction time to peak, supposes that the time that light beam 1 among Fig. 4 reaches peak value is zero point.Solid line in this figure is from the derive cubic function of the association the time to peak (peak) of the corresponding prediction in collimated beam 1 to 8 (sensed position numbering) and their of recurrence.Regression function is represented as follows:

y＝-0.0227x ³+0.4204x ²+1.8345x-2.1685...(10)

Formula (11) below the differential of formula (10) provides.

y＝0.681x ²+0.8408x+1.8345...(11)

Formula (11) is as the function of the speed of motor driver.Based on this function, movably dimmer 29 shown in Figure 3 moves inward on the direction of the radius of substrate 23, and the film that forms on the zone with the film of progressively closing substrate 23 forms.

The optical film thickness of the film on the substrate 23 can so be controlled to guarantee the homogeneity of film thickness.

Fig. 6 (a) is the constructed profile of insulation multilayer film manufacturing installation according to a first aspect of the invention.Referring to Fig. 6, in vacuum chamber 61, splash object element 62 is that film forms the source, and ion gun unit 63 is reaction sources, and they are placed side by side to face rotatable substrate 64.Optical transmitting set 65 is placed on the top of rotatable substrate 64 and the outside of chamber 61.Eight collimated monochromatic ligth flux from 8 passage optical transmitting sets 65 pass logical light window 66, rotatable substrate 64 and following logical light window 67, and are received by the 8 passage optical receivers 68 that are positioned at 61 outsides, chamber.

Eight monochromatic ray flux that received by optical receiver 68 are by being connected with computer 72 with digital signal processor (DSP) 71 by the electrical signal line shown in the dotted line in the figure, 8 passage prime amplifiers, 69,8 passage A/D converters 70.Predicted time when computer 72 calculates the film thickness that reaches expection also stops controlling film thickness by indicating film formation process based on the predicted time that calculates, and predicted time can be regarded as the termination time point of film formation process.

Splash object element 62 has a Ta target 74 and a Si target 15, and they can be put upside down on the vertical position by the mechanism 73 of rotation.Target 74 and 75 has protective layer 74a and 75a respectively, splash gas pipeline 76 thrust by each protective layer 74a, 75a around the space.In the face of rotatable substrate 64, opening 77 is film deposition rate function uniies to (it is positioned at another top) in the target 74,75 by fixed opening 77.Ion gun unit 63 is made of ecr ion rifle 79, has reactive gas pipeline 78 through above it.

Rotatable substrate 64 provides a movably dimmer 81 by CD-ROM drive motor 80 rotations between rotatable substrate 64 and splash object element 62, it is that a film thickness is corrected parts.

Below will be than the structure that describes in greater detail between rotatable substrate 64 and the splash object element 62.Shown in Fig. 6 (b), on substrate 64, along the radius of substrate 64 provide eight monitor the monochromatic ray flux pass through point (monitoring point) 82 to 89.Here, the supervision optical throughput that passes the monitoring point is with such series arrangement, makes wavelength 82 89 more and more longer to the monitoring point from the monitoring point.

Fig. 6 (c) is the top view that comprises the device 61 of this substrate 64.In this figure, splash target 74,75 (not shown) are placed on the bottom, planar disk 77a with permanent opening 77 is placed on the top of splash target, and movably dimmer 81 is placed on the top of planar disk 77a, and rotatable substrate 64 is placed on movably dimmer 81 tops.Above-described permanent opening 77 is used to be controlled at the film deposition rate of the film that forms on the monitor area of substrate 64.In this embodiment, permanent opening 77 forms a fan section along an arc of rotation substrate circumference, so that the film deposition rate of the outer edge of rotation substrate circumference is than the film deposition rate height of its preglabellar field.By the operation of the feed screw (not shown) that driven by the CD-ROM drive motor 81a that is positioned at device outside, the movably dimmer 81 with arc tip edge moves along having the radius of rotation substrate circumference that passes through to put 82 to 89 (not shown) that monitors the monochromatic ray flux linearly.This operation can make dimmer 81 movably close the film formation process of carrying out by permanent opening 77.Movably the motion of translation of dimmer 81 is controlled from the outside of device according to the instruction related with optical receiver 68 from computer 72.

When the insulation multilayer film manufacturing installation shown in Fig. 6 (a) is carried out film thickness control, will reach predetermined pressure state in the chamber 61 by operating in of vacuum pump (not shown).Then, product substrate 64 is rotated by CD-ROM drive motor 80.Then, eight from optical transmitting set 65 monitor that the monochromatic ray flux is compelled to pass optical receiver 68 by last logical light window 66, rotatable substrate 64 and following logical light window 61.Here, eight monitor that homogeneous beams comprise four group of two passage homogeneous beam, and these four groups of homogeneous beams have different supervision wavelength, and each is organized two passages and all has identical wavelength.Movably dimmer 81 is placed in the outside of permanent opening 77, so that rotatable substrate 64 and Ta target 74 or Si target 75 do not have any obstruction toward each other.Argon gas by splash gas pipeline 76 be injected into target 74 or 75 near, and provide predetermined cathode power to form with beginning splash film.In this process, the mixed gas that comprises oxygen and argon gas is injected into ecr ion rifle 79 so that ecr ion rifle 79 discharges neutral radical oxygen, thereby makes the metal nucleic oxidation that comprises Ta or Si that is deposited on the substrate 64.

By adopting in Ta target 74 and the Si target 75 selectively, formation comprises the Ta with high refractive index on product substrate 64 ₂O ₅Film and SiO with low-refraction ₂The alternate multiple film of film.As indicated above, the stratified optical film thickness of each structure of controlling the alternate multiple film with high precision is very important.

Time point when therefore, target 74 or 75 forms the splash film is defined as improving the starting point of the needed film formation time of film thickness.All be assigned to wherein two optical throughputes as above-described four eight supervision homogeneous beam-each light beams that monitor the parallel luminous flux of wavelength, these light beams pass rotatable substrate 64, are received by optical receiver 68 then.Then, each homogeneous beam is converted to voltage signal by 8 passage prime amplifiers 69.Voltage signal is converted to numerary signal by 8 passage A/D converters 70.Numerary signal is imported into DSP71, and there, signal is revert to a quadratic function, the field of definition of this function based on formula (5) be the film formation time 80% beyond period.

Relevant predicted time when reaching the film thickness of expection, this time put and obtains as the film formation termination time that each monitors the monitor area of wavelength, computer 72 orders movably that dimmer 81 moves, and forms monitoring point in will the terminated monitor area so that its pointed portion covers film wherein.So, the film of this monitor area forms and is closed.

According to the present invention, because the segmental permanent opening 77 of the layout of control film deposition rate and supervision wavelength, the monitoring point on the outward flange of rotation substrate circumference reaches peak value earlier.Therefore, speed is moved from the inside edge direction of outward flange of rotating the substrate circumference by the movably dimmer 81 of the instruction control of computer 72.

In case all monitor that film on the monitor area of wavelength forms in this way and stop, the target 75 or 74 that is in idle condition at lower position in the object element 62 is thus lifted to higher position, is used to form next upper layer film.Then, carrying out next film with same way as indicated above forms.By repeating such peak value control process, stacked on each monitor area all finished independently.

On the other hand, time dependent optical film thickness can calculate from the transmissivity initial transmissivity, the transmissivity that obtains when reaching next peak value and the film formation process.In addition, the difference between the film deposition rate optical film thickness that can calculate from the differential of optical film thickness or by fixed intervals obtains.

That is the formula (12) below, the formula (9) that derives from formula (6) of conversion provides.

For example, if monitor that wavelength is 1550nm, the optical film thickness that film forms expection in the time of will stopping is 580nm, and the phase meter that film forms in the time of will stopping is shown as: θ=2 π ^*(optical film thickness)/(supervision wavelength)=134.7 (degree).Suppose that the speed (optical thin film unit) that calculates is 1.2nm/sec (=0.2787 degree/second), current optical film thickness is 500nm (=116.13 degree), and the remaining time X (second) that then arrives end point is represented by following formula (13).

134.7＝116.13+0.2787＊X...(13)

So, X is confirmed as the time: X=66.63 second.That is, not only the calculating of peak value control but also any optical film thickness can provide the termination time point of film formation process.

Relevant predicted time when reaching the film thickness of expection, this time put and obtains as the film formation termination time that each monitors the monitor area of wavelength, computer 72 orders movably that dimmer 81 moves, and forms monitoring point in will the terminated monitor area so that its pointed portion covers film wherein.So, the film of this monitor area forms and is closed.

In case all monitor that film on the monitor area of wavelength forms in this way and stop, the target 75 or 74 that is in idle condition at lower position in the object element 62 is thus lifted to higher position, is used to form next upper layer film.Then, carrying out next film with same way as indicated above forms.By repeating so any film formation process, stacked on each monitor area all finished independently.

Fig. 7 (a) is the constructed profile of insulation multilayer film manufacturing installation according to a second aspect of the invention.Please referring to Fig. 7, in vacuum chamber 91, splash object element 92 is that film forms the source, and ion gun unit 93 is reaction sources, and they are placed side by side to face rotatable substrate 94.Optical transmitting set 95 is placed on the top of rotatable substrate 94 and the outside of chamber 91.Eight collimated monochromatic ligth flux from 8 passage optical transmitting sets 95 pass logical light window 96, rotatable substrate 94 and following logical light window 97, and are received by the 8 passage optical receivers 98 that are positioned at 91 outsides, chamber.

Eight monochromatic ray flux that received by optical receiver 98 are connected with computer 102 with digital signal processor (DSP) 101 by electrical signal line, 8 passage prime amplifiers, 99, the 8 passage A/D converters 100 that the dotted line in the figure shows.Predicted time when computer 102 calculates the film thickness that reaches expection also stops controlling film thickness by indicating film formation process based on the predicted time that calculates, and predicted time can be regarded as the termination time point of film formation process.

Splash object element 92 has a Ta target 104 and a Si target 105, and they can be put upside down on the vertical position by the mechanism 103 of rotation.Target 104 and 105 has protective layer 104a and 105a respectively, splash gas pipeline 106 thrust by each protective layer 104a, 105a around the space.One (it is positioned at another top) in the target 104,105 faced rotatable substrate 94 by fixed opening 107.Ion gun unit 93 is made of ecr ion rifle 109, and this ion gun has reactive gas pipeline 108 through above it.

Rotatable substrate 94 is by CD-ROM drive motor 110 rotations, between rotatable substrate 94 and splash object element 92, variable opening 111a, 111b are provided, they are film deposition rate function uniies, and separate type dimmer 112 to 115, and they are that film thickness is corrected parts.

Below will be than the structure that describes in greater detail between rotatable substrate 94 and the splash object element 92.Shown in Fig. 7 (b); near the separate type dimmer 112,113,114 and 115 that provides substrate 94 starts independently by drive shaft 112a, 113a, 114a and 115a respectively; and be configured to open or close the arc opening zone that forms along concentrically ringed circumference, circumference be by eight on the substrate 94 each that monitor the monochromatic ray flux by point (monitoring point) 116a to the trace drafting of 116h.

Fig. 7 (c) is the top view that comprises the device 91 of substrate 94 and separate type dimmer 112 to 115.In this figure, splash target 104,105 (not shown) are placed on the bottom, planar disk 107a with permanent opening 107 is placed on the top of splash target, and variable opening 111a and 111b are placed on the top of planar disk, and rotatable substrate 94 is placed on separate type dimmer top.Above-described permanent opening 107 is used to control materials evaporated and distributes, so that wider general optical properties to be provided.Opening can be a variable opening.Variable opening 111a, 111b are used to reduce film deposition rate, so that control film thickness with high precision when film formation process almost will finish.Variable opening is replaced splash target 104,105, direct effect can be provided and need the long time because reduce film deposition rate by the output of adjusting the splash target, thereby cause production efficiency to reduce.Promptly, film formation process is to carry out with higher film deposition rate at first, and when film formation process almost will finish, by reducing the variable opening number of degrees of opening 111a, 111b to reduce film deposition rate, film thickness can be precisely controlled.Separate type dimmer 112,113,114 and 115 is withdrawn independently by drive shaft 112a, 113a, 114a and 115a respectively or is extended; to open or close the arc opening zone that forms along concentrically ringed circumference; thereby close the film formation process on the open area, circumference be by each of the supervision monochromatic ray flux on the substrate 94 by some (not shown) 116a to the trace drafting of 116h.The opening/closing of the number of degrees of the opening of variable opening 111a, 111b and separate type dimmer is controlled from the outside of device according to the instruction related with optical receiver 98 from computer 102.

When the insulation multilayer film manufacturing installation shown in Fig. 7 (a) is carried out film thickness control, will reach predetermined pressure state in the chamber 91 by operating in of vacuum pump (not shown).Then, product substrate 94 is rotated by CD-ROM drive motor 110.Then, eight from optical transmitting set 95 monitor that the monochromatic ray flux passes optical receiver 98 by last logical light window 96, rotatable substrate 94 and following logical light window 97.Here, eight monitor that homogeneous beams comprise four group of two passage homogeneous beam, and these four groups of homogeneous beams have different supervision wavelength, and each is organized two passage homogeneous beams and all has identical wavelength.The predetermined number of degrees of the opening of variable opening 111a, 111b keep separate type dimmer 112 to open fully to 115, so that rotatable substrate 94 and Ta target 104 or Si target 105 do not have any obstruction toward each other.Argon gas injected by splash gas pipeline 106 targets 104 or 105 near, and provide predetermined cathode power with the formation of beginning splash film.In this process, the mixed gas that comprises oxygen and argon gas is injected ecr ion rifle 109 so that ecr ion rifle 109 discharges neutral radical oxygen from reactive gas pipeline 108, thereby makes the metal nucleic oxidation that comprises Ta or Si that is deposited on the substrate 94.

By adopting in Ta target 104 and the Si target 105 selectively, formation comprises the Ta with high refractive index on product substrate 94 ₂O ₅Film and SiO with low-refraction ₂The alternate multiple film of film.As indicated above, the stratified optical film thickness of each structure of controlling the alternate multiple film with high precision is very important.

Time point when therefore, target 104 or 105 forms the splash film is defined as improving the starting point of the needed film formation time of film thickness.All be assigned to wherein two optical throughputes as above-described four eight supervision homogeneous beam-each light beams that monitor the parallel luminous flux of wavelength, these light beams pass rotatable substrate 94, are received by optical receiver 98 then.Then, each homogeneous beam is converted to voltage signal by 8 passage prime amplifiers 99.Voltage signal is converted to numerary signal by 8 passage A/D converters 100.Numerary signal is imported into DSP101, and there, signal is revert to a quadratic function, and the territory of this function is the film formation time that the time point when variable opening is activated begins based on formula (5).

Relevant predicted time as when reaching the film thickness of expection corresponding to the maximum value of quadratic regression function or the film formation time of minimum value, computer 102 order separate type dimmers 112 to 115 cut out, thereby close the film formation process of arc monitor area.

In case all monitor that film on the monitor area of wavelength forms in this way and stop, the target 105 or 104 that is in idle condition at lower position in the object element 92 is thus lifted to higher position, is used to form next upper layer film.Then, carrying out next film with same way as indicated above forms.By repeating such process, stacked on each monitor area all finished independently.

[example]

In example 1 to 4, use execution shown in Figure 3 accuracy according to the control of the optical film thickness of the optical thin film of the optical film thickness control device acquisition of control method of the present invention with discussing.

[example 1]

In film thickness control device shown in Figure 3, (wavelength X: 1552nm) incided substrate, movably the motion of dimmer 29 is not terminated incoming beam of ramose.Under this state, on substrate 23, form Ta by splash ₂O ₅Single thin film.Suppose Ta ₂O ₅Film is a high refractive index layer, wherein Ta ₂O ₅The optical film thickness of film is that the state of λ/4 is represented by character " H ", has formed a H single thin film and a HH single thin film on glass substrate.In forming process, when forming the H single thin film, attempt predicting the film rise time when the transmissivity of measuring reaches the lowest point (minimum value in the quadratic regression function), when forming the HH single thin film, attempt predicting the film rise time when the transmissivity of measuring reaches peak value (maximum value in the quadratic regression function).

Here, above-described the lowest point is relevant with the variation of the transmissivity of measurement with peak value.It should be noted that if calculate down transmissivity based on transmissivity, the lowest point and peak value need be handled in opposite mode so.Obscure for avoiding any, as one man think in this example, the lowest point is relevant with transmissivity with peak value.For following example, identical reason is also correct.

Suppose Ta ₂O ₅Sedimentation rate be 0.17nm/sec, use at Ta from ought forming ₂O ₅The optical film thickness of film reach 80% o'clock of λ/4 to respect to the peak value of reality or 2 seconds of front, the lowest point the time measurement that obtains in this time period data set, data set is imported into and is used to carry out the CPU18 of data processing and revert to the quadratic function that falls transmissivity based on formula (5).

Then, carry out to check by this way, even the determined value of film rise time that peak value of determining peak value or the lowest point after or the lowest point are located compares with the predictor of film rise time of peak value of deriving from the quadratic regression function or the lowest point.Drafting checks that by carrying out from above-mentioned determined value the mean value that obtains for 10 times can be considered as mean error, and this mean error and standard deviation show in following table 1.

In this example, the measurement data set that obtain 2 seconds before the peak value of reality or the lowest point is carried out returned.Yet, confirm that the measurement data set that obtain 30 seconds before the peak value of reality or the lowest point provides identical result.

[example 1 relatively]

The film of the film rise time of the H single thin film at the lowest point place and the HH single thin film at peak value place be rise time with example 1 in same way as predict that just regression function is the quadratic function of transmissivity.Mean error of Huo Deing and standard deviation show in following table 1 in this example.

[table 1]

As can be seen from Table 1, only when the film formation time of the H single thin film at prediction the lowest point place relatively example 1 provide than example 1 value more accurately.Yet under other all situations, regression function is down that the example 1 of the function of transmissivity provides frequently example 1 higher accuracy.

[example 2]

Use the optical film thickness control device, this device is identical with device in the example 1 shown in Figure 3, and just splashing device is replaced by reactive splashing device, goes up the various multilayer film of formation in glass substrate (BK7).Each film in the multilayer film is all by the Ta that is high refractive index layer (H) ₂O ₅Film and be the SiO of low-index layer (L) ₂The alternating layer of film is formed, and for each multilayer film, predicts the film rise time when reaching peak value or the lowest point.The multilayer film that use are as follows.The character of after alternating layer, describing (P) and (B) respectively the time of expression prediction be time when reaching peak value, and the time of predicting is the time when reaching the lowest point.

H(B)，HH(P)，HL(P)，HLL(B)，HLH(B)，HLHH(P)，HLHL(P)，HLHLL(B)，HLHLH(B)，HLHLHH(P)，HLHLHL(P)，HLHLHLL(P)，HLHLHLH(B)，HLHLHLHH(P)

In this example, suppose Ta ₂O ₅Sedimentation rate be 0.17nm/sec, use at Ta from ought forming ₂O ₅The optical film thickness of film reaches the data set of the measurement that obtained in this time period during 2 seconds to peak value or front, the lowest point with respect to reality of λ/4 at 85% o'clock.Data set is imported into and is used to carry out the CPU18 of data processing and revert to the quadratic function that falls transmissivity based on formula (5).

Be labeled as among Fig. 8 " example 2 " graphic presentation the association between the layout layer of the multilayer film of horizontal plot on X axis and its regression error (mean error among Fig. 8) at vertical plot on X axis.

[example 2 relatively]

The film of each multilayer film in the example 2 at peak value or the lowest point place be rise time with example 2 in same way as predict that just regression function is the quadratic function of transmissivity.The data of using are checked 10 acquisitions by carrying out.Be labeled as among Fig. 8 " relatively example 2 " graphic presentation the association between the layout layer of the multilayer film of horizontal plot on X axis and its regression error at vertical plot on X axis.

The fact below relatively having shown between example 2 and the example 2 relatively.In example 2 relatively, promptly, if regression function is the quadratic function of transmissivity, multilayer film that constitute for the number of plies by lesser amt then, the figure that is drawn is less with the deviation ratio at the determined value (being positioned at the value on the line that mean error was 0 second) of film rise time at peak value or place, the lowest point.Yet, the multilayer film that constitute for the number of plies by bigger quantity, the error of the predictor of film rise time at the peak value place that occurs after transmissivity increases becomes greatly.

In addition, in example 2, that is,,, can keep higher accuracy and stability then for each multilayer film if regression function is down the quadratic function of transmissivity.

[example 3]

Be not the various multilayer film that form in the example 2, but the reactive spraying and splashing facility in the usage example 2 form by Ta ₂O ₅The single thin film that film constitutes, the film rise time when reaching peak value or the lowest point with identical optical film thickness control method prediction.

In this example, used the Ta that ought form ₂O ₅When the optical film thickness of film reaches particular value in predetermined per-cent (70 to the 90%) scope of λ/4 and the measurement data set that obtains after this moment.Data set be imported into be used to carry out the CPU18 of data processing and revert to based on formula (5) fall the quadratic function of transmissivity, and use the quadratic regression function to predict.

In Fig. 9, regression error is drawn on the left vertical axle, returning starting point (λ/4 70 to 90% length-specific) is plotted on the transverse axis, the graphic presentation of being labeled as among Fig. 9 " example 3-1E " attribute that when carrying out prediction, produces at the lowest point place, be labeled as " example 3-2E " graphic presentation the attribute of generation when carrying out prediction at the peak value place.

Fig. 9 be at the vertical plot on X axis in right side the composite figure of standard deviation.In this figure, the standard deviation at the predicted time place among the example 3-1E is noted as " example 3-1 σ ", and the standard deviation at the predicted time place among the example 3-2E is noted as " example 3-2 σ ".

[example 3 relatively]

Film rise time is to predict with the same way as in the example 3, has just used the quadratic regression function of transmissivity in recurrence.The graphic presentation of being labeled as among Fig. 9 " relatively example 3-1E " attribute that when carrying out prediction, produces at the place, the lowest point, the graphic presentation of being labeled as among Fig. 9 " example 3-2E relatively " when the attribute of carrying out generation when predicting at the peak value place.

In addition, in Fig. 9, the standard deviation at the predicted time place among the example 3-1E relatively is noted as " example 3-1 σ relatively ", and the standard deviation at the predicted time place among the example 3-2E relatively is noted as " example 3-2 σ relatively ".

Comparison shows that between example 3 and the example 3 relatively in two examples, approached peak value or the lowest point (return starting point and approach 100%) if return starting point, and it is higher that accuracy becomes, though that standard deviation becomes is bigger, and discrete the increase.Specifically, in example 3 relatively (example 3-2E relatively), in the prediction at peak value place, do not provide enough accuracies.

Verified, falling under the situation of quadratic regression curve of transmissivity in having used example 3 returns a point that is expected in 75 to 90% scope of λ/4 and begins.

[example 4]]

Prepared a BPF (bandpass filter) according to the film thickness control method that optical film thickness control device shown in Figure 3 is carried out.This bandpass filter is one 7 cavity bandpass filter, comprises by Ta ₂O ₅Film (H) and SiO ₂What film (L) was formed replaces 155 layers.Bandpass filter is arranged as follows.

Air | ARC|HLHLHLHL2HLHLHLHLHL

HLHLHLHL0.39H0.2065L(A)0.39H(B)L2HL0.39H0.2065L(A)0.39H(B)LHL

HLHLHL

HLHLHLHLHL2HLHLHLHLHLHL

HLHLHLHLHL2HLHLHLHLHLHL

HLHLHLHLHL2HLHLHLHLHLHL

HLHLHLHL0.39H0.2065L(A)0.39H(B)L2HL0.39H0.2065L(A)0.39H(B)LHL

HLHLHL

HLHLHLHL2HLHLHLHLH| glass

In this layout, the index " B " that is assigned to the Ta2O5 film represents that its sedimentation rate is by calculating by falling the time diffusion of the optical film thickness that the conversion of transmissivity obtains, rather than come out by the quadratic function regression Calculation of peak value or the lowest point control, it is to form the termination time by any film thickness control method based on sedimentation rate prediction film to put and come terminated that film forms.

In this layout, index " A " the expression splash speed that is assigned to the SiO2 film is provided with before being, its film thickness is based on that depositing time controls.

So the film thickness of the bandpass filter that obtains is to control under such condition, promptly used the supervision wavelength of 1552nm, used diameter to be 300mm and glass disc with ARC (antireflecting coating) on its posterior face, emission optical measurement transmitter (transmitter in the photorectifier 16 among Fig. 3) is placed on from eight points of the outside 10mm fixed intervals 10mm far away of range hadn wheel.

Bandpass filter has spectrum as shown in figure 10, and has confirmed, bandpass filter is the insulation film that has satisfied attribute in whole monitoring range.

Now, in example 5 to 7, will the accuracy of control of the optical film thickness of the optical thin film product that the insulation multilayer film manufacturing installation of the execution shown in Fig. 6 according to control method of the present invention provide be discussed.

[example 5]

Prepared middle band bandpass filter by the insulation multilayer film manufacturing installation among Fig. 6, this this in the band bandpass filter comprise that one is folded by being the Ta of high refractive index layer ₂O ₅Film and be the SiO of low-index layer ₂The alternating layer that film is formed, the stratified optical film thickness of all structures are the integral multiples of λ/4 (λ: monitor wavelength).The supervision wavelength that uses is 1552.52nm, 1554.12nm, 1555.72nm and 1552.32nm.Optical thin film is arranged as follows.

The glassy product substrate (BK7) that has antireflecting coating |

(HL) ³L (HL) ⁶L (HL) ⁶L (HL) ³The I air

For low-index layer, the design load of specific refractory power is set to 1.444, for high refractive index layer, is 2.08, for product substrate (BK7), is 1.5.

Please referring to Fig. 6 (b), be that the position of the inside 5mm in outside of the product substrate 64 of 300mm is provided with and the monitoring point 82 that monitors that homogeneous beam passage 1 is related at the distance diameter.On the direction at the center of rotation substrate circumference, be provided with the monitoring point 83 to 89 related respectively from monitoring point 82 with passage 2 to 8 every 10mm position at interval.

In eight monochromatic ray flux that the adjustable laser source of the optical transmitting set from be equivalent to Fig. 6 65 sends, passage 1 and 2 is assigned to and monitors that wavelength is the monochromatic ray flux of 1552.52nm, passage 3 and 4 is assigned to and monitors that wavelength is the monochromatic ray flux of 1554.12nm, passage 5 and 6 is assigned to and monitors that wavelength is the monochromatic ray flux of 1555.72nm, and passage 7 and 8 is assigned to and monitors that wavelength is the monochromatic ray flux of 1557.32nm.For the optical throughput that optical receiver 68 receives, transmissivity is calculated by DSP71.The transmissivity that use calculates is carried out quadratic function and is returned near the peak value of transmittance graph, thereby calculates the predicted time when reaching peak value.This predicted time is considered to the termination time point of film formation process.

Figure 11 has shown by the property distribution on the product substrate 64 of carrying out above-described process acquisition repeatedly.As shown in figure 11, width is approximately each endless belt-shaped regional 90 to 93 optical properties with unanimity of 10mm.

Figure 12 has shown the movably figure of the motion of dimmer 81 of indication that the response film forms the termination time point, and this indication is to obtain by the control of the peak value on the 3rd layer, and the 3rd layer be low-index layer.As can be seen, movably dimmer 81 is controlled from this figure, so that moving to the direction around interior from the outside of rotation substrate circumference with variable speed.

Figure 13 has shown the spectral-transmission favtor attribute of the monitor area related with passage 1 to 8 on the substrate.The optical articles of the satisfaction of band bandpass filter in the conduct is provided as can be seen.

[example 6]

Prepared middle band bandpass filter by the insulation multilayer film manufacturing installation among Fig. 6, band bandpass filter comprises that one is folded by being the Ta of high refractive index layer in this ₂O ₅Film and be the SiO of low-index layer ₂The alternating layer that film is formed, the stratified optical film thickness of all structures are the integral multiples of λ/4 (λ: monitor wavelength).The supervision wavelength that uses is 1552.52nm, 1553.32nm, 1554.12nm and 1554.92nm.Optical thin film is arranged as follows:

The glassy product substrate (BK7) that has antireflecting coating |

(HL) ⁸L (HL) ¹⁶L (HL) ¹⁶L (HL) ⁸| air

For low-index layer, the design load of specific refractory power is set to 1.444, for high refractive index layer, is 2.08, for product substrate (BK7), is 1.5.

Please referring to Fig. 6 (b), be that the position of the inside 5mm in outside of the product substrate 64 of 300mm is provided with and the monitoring point 82 that monitors that homogeneous beam passage 1 is related at the distance diameter.On the direction at the center of rotation substrate circumference, be provided with the monitoring point 83 to 89 related respectively from monitoring point 82 with passage 2 to 8 every 10mm position at interval.

In eight monochromatic ray flux that the adjustable laser source of the optical transmitting set from be equivalent to Fig. 6 65 sends, passage 1 and 2 is assigned to and monitors that wavelength is the monochromatic ray flux of 1552.52nm, passage 3 and 4 is assigned to and monitors that wavelength is the monochromatic ray flux of 1553.32nm, passage 5 and 6 is assigned to and monitors that wavelength is the monochromatic ray flux of 1554.12nm, and passage 7 and 8 is assigned to and monitors that wavelength is the monochromatic ray flux of 1554.92nm.For the optical throughput that optical receiver 68 receives, the transmissivity of falling is to calculate from the transmissivity that is calculated by DSP71.Use calculates falls transmissivity, is falling to carry out quadratic function near the peak value of transmittance graph and return, thereby is calculating predicted time when reaching peak value.This predicted time is considered to the termination time point of film formation process.

Figure 14 has shown the spectral-transmission favtor attribute of the monitor area related with passage 1 to 8 on the substrate.The optical articles of the satisfaction of band bandpass filter in the conduct is provided as can be seen.

[example 7]

Insulation multilayer film manufacturing installation among Fig. 6 has been prepared anti-reflection film, and this anti-reflection film comprises by being the Ta of high refractive index layer ₂O ₅Film and be the SiO of low-index layer ₂The alternating layer that film is formed, first and second layers optical film thickness are not the integral multiples of λ/4 (λ: monitor wavelength), and the film of last upper layer (second layer) forms the termination time point and predicted by peak value control.The supervision wavelength that uses is 1550nm, 1555nm, 1560nm and 1565nm.Optical thin film is arranged as follows:

The glassy product substrate (BK7) that has antireflecting coating |

0.35H, the 1.288L| air

For low-index layer, the design load of specific refractory power is set to 1.444, for high refractive index layer, is 2.08, for product substrate (BK7), is 1.5.

Please referring to Fig. 6 (b), be that the position of the inside 5mm in outside of the product substrate 64 of 300mm is provided with and the monitoring point 82 that monitors that homogeneous beam passage 1 is related at the distance diameter.On the direction at the center of rotation substrate circumference, be provided with the monitoring point 83 to 89 related respectively from monitoring point 82 with passage 2 to 8 every 10mm position at interval.

In eight monochromatic ray flux that the adjustable laser source of the optical transmitting set from be equivalent to Fig. 6 65 sends, passage 1 and 2 is assigned to and monitors that wavelength is the monochromatic ray flux of 1550nm, passage 3 and 4 is assigned to and monitors that wavelength is the monochromatic ray flux of 1555nm, passage 5 and 6 is assigned to and monitors that wavelength is the monochromatic ray flux of 1560nm, and passage 7 and 8 is assigned to and monitors that wavelength is the monochromatic ray flux of 1565nm.For the optical throughput that optical receiver 68 receives, the transmissivity of falling is to calculate from the transmissivity that is calculated by DSP71.For the first layer, the transmissivity of falling is used to predict that the film of 0.35H forms the termination time point, for the second layer, falling to carry out quadratic function near the peak value of transmittance graph and return, to calculate the predicted time when reaching peak value, this predicted time is considered to the termination time point of film formation process.

Figure 15 has shown the spectral reflectivity attribute of the monitor area related with passage 1 to 8 on the substrate.As can be seen, provide optical articles as the satisfaction of anti-reflection film.

Next, in the example 8 to 10 below, will the accuracy of control of the optical film thickness of the optical thin film product that the insulation multilayer film manufacturing installation of the execution shown in Fig. 7 according to control method of the present invention provide be discussed.

[example 8]

Prepared middle band bandpass filter by the insulation multilayer film manufacturing installation among Fig. 7, band bandpass filter comprises that one is folded by the Ta that is high refractive index layer in this ₂0 ₅Film and be the SiO of low-index layer ₂The alternating layer that film is formed, the stratified optical film thickness of all structures are the integral multiples of λ/4 (λ: monitor wavelength).The supervision wavelength that uses is 1552.52nm, 1554.12nm, 1555.72nm and 1557.32nm.Optical thin film is arranged as follows:

The glassy product substrate (BK7) that has antireflecting coating |

(HL) ³L (HL) ⁶L (HL) ⁶L (HL) ³| air

For low-index layer, the design load of specific refractory power is set to 1.444, for high refractive index layer, is 2.08, for product substrate (BK7), is 1.5.

Please referring to Fig. 7 (b), be that the position of the inside 5mm in outside of the product substrate 94 of 300mm is provided with and the monitoring point 116a that monitors that homogeneous beam passage 1 is related at the distance diameter.On the direction at the center of rotation substrate circumference, be provided with the monitoring point 116b related respectively to 116h from monitoring point 116a with passage 2 to 8 every 10mm position at interval.

In eight monochromatic ray flux that the adjustable laser source of the optical transmitting set from be equivalent to Fig. 7 95 sends, passage 1 and 2 is assigned to and monitors that wavelength is the monochromatic ray flux of 1552.52nm, passage 3 and 4 is assigned to and monitors that wavelength is the monochromatic ray flux of 1554.12nm, passage 5 and 6 is assigned to and monitors that wavelength is the monochromatic ray flux of 1555.72nm, and passage 7 and 8 is assigned to and monitors that wavelength is the monochromatic ray flux of 1557.32nm.For the optical throughput that optical receiver 98 receives, transmissivity is calculated by DSP101.The transmissivity that use calculates is carried out quadratic function and is returned near the peak value of transmittance graph, thereby calculates the predicted time when reaching peak value.This predicted time is considered to the termination time point of film formation process.Figure 16 has shown by the property distribution on the product substrate 94 of carrying out this process acquisition repeatedly.As shown in figure 16, width is approximately each endless belt-shaped regional 117 to 120 optical properties with unanimity of 10mm.

Figure 17 has shown the spectral-transmission favtor attribute of the monitor area related with passage 1 to 8 on the substrate.The optical articles of the satisfaction of band bandpass filter in the conduct is provided as can be seen.

[example 9]

Prepared middle band bandpass filter by the insulation multilayer film manufacturing installation among Fig. 7, band bandpass filter comprises that one is folded by the Ta that is high refractive index layer in this ₂O ₅Film and be the SiO of low-index layer ₂The alternating layer that film is formed, the stratified optical film thickness of all structures are the integral multiples of λ/4 (λ: monitor wavelength).The supervision wavelength that uses is 1552.52nm, 1553.32nm, 1554.12nm and 1554.92nm.Optical thin film is arranged as follows:

The glassy product substrate (BK7) that has antireflecting coating |

(HL) ⁸L (HL) ¹⁶L (HL) ¹⁶L (HL) ⁸| air

For low-index layer, the design load of specific refractory power is set to 1.444, for high refractive index layer, is 2.08, for product substrate (BK7), is 1.5.

Please referring to Fig. 7 (b), be that the position of the inside 5mm in outside of the product substrate 94 of 300mm is provided with and the monitoring point 116a that monitors that homogeneous beam passage 1 is related at the distance diameter.On the direction at the center of rotation substrate circumference, be provided with the monitoring point 116b related respectively to 116h from monitoring point 116a with passage 2 to 8 every 10mm position at interval.

In eight monochromatic ray flux that the adjustable laser source of the optical transmitting set from be equivalent to Fig. 7 95 sends, passage 1 and 2 is assigned to and monitors that wavelength is the monochromatic ray flux of 1552.52nm, passage 3 and 4 is assigned to and monitors that wavelength is the monochromatic ray flux of 1553.32nm, passage 5 and 6 is assigned to and monitors that wavelength is the monochromatic ray flux of 1554.12nm, and passage 7 and 8 is assigned to and monitors that wavelength is the monochromatic ray flux of 1554.92nm.For the optical throughput that optical receiver 98 receives, the transmissivity of falling is to calculate from the transmissivity that is calculated by DSP101.Use calculates falls transmissivity, is falling to carry out quadratic function near the peak value of transmittance graph and return, thereby is calculating predicted time when reaching peak value.This predicted time is considered to the termination time point of film formation process.

Figure 18 has shown the spectral-transmission favtor attribute of the monitor area related with passage 1 to 8 on the substrate.The optical articles of the satisfaction of band bandpass filter in the conduct is provided as can be seen.

[example 10]

Insulation multilayer film manufacturing installation among Fig. 7 has been prepared anti-reflection film, and this anti-reflection film comprises by the Ta that is high refractive index layer ₂O ₅Film and be the SiO of low-index layer ₂The alternating layer that film is formed, first and second layers optical film thickness are not the integral multiples of λ/4 (λ: monitor wavelength), and the film of last upper layer (second layer) forms the termination time point and predicted by peak value control.The supervision wavelength that uses is 1550nm, 1555nm, 1560nm and 1565nm.Optical thin film is arranged as follows:

The glassy product substrate (BK7) that has antireflecting coating |

0.35H, the 1.288L| air

For low-index layer, the design load of specific refractory power is set to 1.444, for high refractive index layer, is 2.08, for product substrate (BK7), is 1.5.

Please referring to Fig. 7 (b), be that the position of the inside 5mm in outside of the product substrate 94 of 300mm is provided with and the monitoring point 116a that monitors that homogeneous beam passage 1 is related at the distance diameter.On the direction at the center of rotation substrate circumference, be provided with the monitoring point 116b related respectively to 116h from monitoring point 116a with passage 2 to 8 every 10mm position at interval.

In eight monochromatic ray flux that the adjustable laser source of the optical transmitting set from be equivalent to Fig. 7 95 sends, passage 1 and 2 is assigned to and monitors that wavelength is the monochromatic ray flux of 1550nm, passage 3 and 4 is assigned to and monitors that wavelength is the monochromatic ray flux of 1555nm, passage 5 and 6 is assigned to and monitors that wavelength is the monochromatic ray flux of 1560nm, and passage 7 and 8 is assigned to and monitors that wavelength is the monochromatic ray flux of 1565nm.For the optical throughput that optical receiver 98 receives, the transmissivity of falling is to calculate from the transmissivity that is calculated by DSP101.For the first layer, the transmissivity of falling is used to predict that the film of 0.35H forms the termination time point, for the second layer, falling to carry out quadratic function near the peak value of transmittance graph and return, to calculate the predicted time when reaching peak value, this predicted time is considered to the termination time point of film formation process.

Figure 19 has shown the spectral reflectivity attribute of the monitor area related with passage 1 to 8 on the substrate.As can be seen, provide optical articles as the satisfaction of anti-reflection film.

From top description as can be seen, according to optical film thickness control method of the present invention, at every turn when up-to-date upper layer film that change will form, the watch-dog substrate must not replace with new watch-dog substrate, also there is no need to adopt the extra layout (as situation of the prior art) of the phase differential that is used to improve measurement precision, because carry out peak value or the lowest point control.Therefore, this process obtains simplifying.In addition,, carry out peak value or the lowest point prediction, so, can control film thickness with high precision by quadratic regression with satisfied association owing to used transmissivity.

In addition,, promptly directly monitor, so needn't consider the reproducibility of the film that monitors owing to can carry out the in-situ measurement of product film.

In the membrane according to the invention thickness control device, many collimated beams are used to monitor film thickness.Therefore, the distribution of the film thickness of up-to-date upper layer film can be detected, so, the high uniformity of film thickness can be guaranteed with high precision.

By insulation multilayer film manufacturing installation according to the present invention, transmissivity or fall transmissivity peak value near the execution quadratic function return the predicted time when being used as the film thickness that reaches expection rise time corresponding to the film of the maximum value of the regression function that produces or minimum value.So, can be with the optical film thickness of high precision control increase, in addition, the direct method for monitoring that relates to various supervision wavelength can provide bigger monitor area, thereby can provide satisfied attribute for insulation film.Therefore, can produce high-quality optical thin film product on a large scale, this product is the equipment that is used for dense wavelength division multiplexed system such as narrow-band pass filter.

In addition, comprise that the insulation multilayer film by the bandpass filter of above-described optical film thickness control device or the manufacturing of insulation multilayer film manufacturing installation has satisfied optical properties, correspondingly, performance is also high.

Quote the description of numeral

1,61 and 91: vacuum chamber

2: electron gun

2a: photochopper

4,23,64 and 94: rotatable substrate

12: adjustable lasing light emitter

13: fiber coupler

14: the fiber optic collimator instrument

15: the splash film former

16: photodiode

17,70 and 100:8 passage A/D converter (A/D converter)

18:CPU (controller)

19: motor driver (controller)

20 and 21: optical fiber

28,62 and 92: splash object element (film formation source)

29 and 81: photochopper movably

63 and 93: ion gun unit (reaction source)

65 and 95: optical transmitting set

66 and 96: upward lead to light window

67 and 97: lower logical light window

68 and 98: optical receiver (luminous intensity measurement device)

69 and 99:8 passage preamplifier

71 and 101: digital signal processor (DSP)

72 and 102: computer

74 and the 104:Ta target

75 and the 105:Si target

76 and 106: the splash gas pipeline

77 and 107: permanent opening

78 and 108: reactive gas pipeline

79 and the 109:ECR ion gun

82 to 89: the monitoring point

111a and 111b: variable opening (film deposition rate function unit)

112 to 115: separate type dimmer (film thickness correction parts)

116a is to 116h: the monitoring point

Claims (4)

1. insulation multilayer film manufacturing installation, its vacuum chamber that is used to make has thin-film material source and reaction source, each source is all placed side by side to face rotatable substrate, this manufacturing installation comprises: the film deposition rate function unit, it has a variable opening, to control the film deposition rate of the insulation multilayer film that forms on the said rotatable substrate; Film thickness is corrected parts, it has an arcual opening, be used to be corrected in the film thickness of the insulation multilayer film that forms on the said rotatable substrate, said film thickness is corrected parts and is used the separate type dimmer, this dimmer opens or closes independently along the arc opening zone that concentrically ringed circumference forms and forms with blocking thin film, and this film deposition rate function unit and film thickness are corrected parts and provided between said rotatable substrate and said thin-film material source; The luminous intensity measurement device is used to measure the monochromatic intensity of supervision of passing a plurality of monitoring points along the radius of said rotatable substrate; And Controlling System; the variation that is used to respond when each of one or more wavelength monitors that monochromatic ray flux passes said monitoring point by the light intensity of said luminous intensity measurement measurement device starts the opening that said film thickness is corrected parts; wherein; the movably opening that said film thickness is corrected parts comprises the separate type dimmer; this dimmer opens or closes the arc opening zone that forms along concentrically ringed circumference independently; this circumference is to draw by the trace in each monitoring point when said rotatable substrate rotation, and wherein said thin-film material source comprises and forms Ta at least ₂O ₅The high refractive index layer of film and SiO ₂The splash target of the Ta of the low-index layer of film and Si, and described splash target is to provide in the mode that can select any target.

2. insulation multilayer film manufacturing installation according to claim 1, it is characterized in that, the said Controlling System of this insulation multilayer film manufacturing installation is measured the variation by the light intensity of luminous intensity measurement measurement device, the variation of transmissivity when passing each monitoring point in a plurality of monitoring points as the supervision monochromatic ray flux that comprises one or more wavelength in the period that on said rotatable substrate, forms insulation multilayer film, the inverse of definition transmissivity is for falling transmissivity, reach in measurement data set before its maximum value or minimum value, by method of least squares this measurement data set of two variablees is revert to quadratic function, these two variablees are just in the needed film of increase rise time of the film thickness of sedimentary up-to-date upper layer film and the said transmissivity of falling, and the maximum of points of use and said quadratic regression function or minimum point consistent film rise time reaches the predicted time of the optical film thickness at said maximum value of falling transmissivity or minimum value place as said up-to-date upper layer film, based on interference theory, said maximum value of falling transmissivity and minimum value distribute every the gap periods ground of 1/4 the optical film thickness that is equivalent to said monochromatic wavelength.

3. insulation multilayer film manufacturing installation according to claim 2, it is characterized in that, growth along with the film thickness of said up-to-date upper layer film, said film increases by based on falling optical film thickness that transmissivity calculates and detect said up-to-date upper layer film and reached predetermined optical film thickness and control from said, and the said transmissivity of falling distributes every the gap periods ground of 1/4 the optical film thickness that is equivalent to monochromatic wavelength.

4. according to any one insulation multilayer film manufacturing installation in the claim 1 to 3, it is characterized in that said reaction source sends reactive neutral radical gas.

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