KR100782000B1 - Spatial optical modulator having a plurality of passivation layers - Google Patents

Abstract

Board; An insulating layer on the substrate; A structure layer having a central portion spaced apart from the insulating layer by a predetermined distance; Located on the structure layer, the piezoelectric drive body for moving the central portion of the structure layer up and down; A first passivation layer disposed on the piezoelectric drive body and protecting the piezoelectric drive body; And a plurality of passivation layers disposed on the first passivation layer and including a second passivation layer protecting the first passivation layer. According to the present invention, the malfunction of the piezoelectric drive body due to moisture absorption and the like can be minimized through the plurality of passivation layers including the aluminum oxide film. In addition, through this there is an effect that can maximize the light diffraction characteristics and reliability of the optical modulator device.

Optical modulator element, piezoelectric driver, passivation layer.

Description

Spatial optical modulator having a plurality of passivation layers

1 is a perspective view showing one embodiment of a piezoelectric type optical modulator element applicable to a preferred embodiment of the present invention.

Figure 2 is a perspective view showing another form of the piezoelectric optical modulator device applicable to the preferred embodiment of the present invention.

3 is a plan view of an array of optical modulator elements composed of the optical modulator elements of FIG.

4 is a view for explaining a principle of light modulation in the optical modulator element array of FIG.

5 is a perspective view showing the structure of an optical modulator device having a plurality of passivation layers according to an embodiment of the present invention.

FIG. 6 is a cross-sectional view of an optical modulator element having a plurality of passivation layers shown in FIG.

FIG. 7 is a cross-sectional view illustrating a manufacturing process of an optical modulator device having a plurality of passivation layers shown in FIG. 5. FIG.

8 is a cross-sectional view of an optical modulator device having a plurality of passivation layers according to another preferred embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

110: substrate 120: insulating layer

130: sacrificial layer 140: structure layer

150: piezoelectric drive body 151: lower electrode

152: piezoelectric layer 153: upper electrode

160: passivation layer 161: first passivation layer

162: second passivation layer 163: third passivation layer

The present invention relates to a MEMS structure and a method of manufacturing the same, and more particularly, to an optical modulator device and a method of manufacturing the same.

MEMS (Micro Electro Mechanical System) refers to a micro electromechanical system or device, and MEMS technology is a technology for forming a three-dimensional structure on a silicon substrate using semiconductor manufacturing technology. MEMS is applied to the optical field as one of various application fields. MEMS technology enables the fabrication of optical components smaller than 1mm, enabling ultra-compact optical systems. Micro-optical components such as optical modulator elements and micro lenses, which are miniature optical systems, have been adopted and applied to communication devices, displays, and recording devices due to advantages such as fast response speed, small loss, and ease of integration and digitization.

 An optical modulator element is a circuit or device for transmitting a signal to light (optical modulation) in a transmitter when a free space of an optical fiber or an optical frequency band is used as a transmission medium. The optical modulator element is divided into a direct method of directly controlling the on / off of light and an indirect method using reflection and diffraction of light, and the indirect method is divided into an electrostatic method and a piezoelectric method according to the method of being driven again.

In this case, the indirect optical modulator device performs the optical modulation through interference generated by the path difference of the reflected light reflected by the incident light regardless of the driving method. In particular, in the piezoelectric type optical modulator device, a path difference of reflected light is generated by using a driving force of a piezoelectric driver that contracts and expands according to a predetermined voltage applied (see description of FIGS. 3 and 4 to be described later). Therefore, in the piezoelectric optical modulator device, the role of the piezoelectric driver is particularly important for realizing optical diffraction characteristics.

However, according to the related art, as the manufacturing process of the optical modulator device proceeds, there is a problem in that the operating characteristics of the piezoelectric driving body are changed due to the influence of moisture absorption of the surrounding moisture. When the operating characteristics of the piezoelectric actuator are changed, the height (interval) between the ribbon and the insulating layer in the optical modulator element is also changed, and the optical diffraction characteristics and reliability of the entire optical modulator element are deteriorated by such a change in height. .

Accordingly, the present invention provides an optical modulator device and a method of manufacturing the same that can maximize the light diffraction characteristics and reliability thereof of the optical modulator device.

In addition, in order to prevent deterioration of the characteristics of the optical modulator device, an optical modulator device and a method of manufacturing the same that can minimize the malfunction of the piezoelectric drive body due to moisture absorption of the surroundings.

Other objects of the present invention will be readily understood through the following description.

According to an aspect of the invention, the substrate; An insulating layer on the substrate; A structure layer having a central portion spaced apart from the insulating layer by a predetermined distance; Located on the structure layer, the piezoelectric drive body for moving the central portion of the structure layer up and down; A first passivation layer disposed on the piezoelectric drive body and protecting the piezoelectric drive body; And a plurality of passivation layers disposed on the first passivation layer, the second passivation layer protecting the first passivation layer.

In addition, the optical modulator device having a plurality of passivation layers according to the present invention may further include a sacrificial layer positioned above the insulating layer and below the structure layer, and supporting the structure layer. The sacrificial layer may be etched away from the insulating layer by a predetermined distance from the lower portion of the center portion of the structure layer.

In addition, the piezoelectric drive body of the present invention; A piezoelectric layer positioned on the lower electrode and contracting and expanding according to a predetermined voltage to generate vertical driving force in a central portion of the structure layer; And an upper electrode disposed on the piezoelectric layer and applying a predetermined voltage formed on the piezoelectric layer between the lower electrodes.

In addition, the optical modulator device having a plurality of passivation layers according to the present invention may further include a third passivation layer positioned above the piezoelectric driver and below the first passivation layer to protect the piezoelectric driver. Here, the third passivation layer may be an Al ₂ O ₃ film.

In this case, the first passivation layer may be a SiO ₂ film, and the thickness of the first passivation layer may be 10 ⁻³ μm or more and 1 μm or less.

In this case, the second passivation layer may be an aluminum oxide film, and the thickness of the second passivation layer may be 10 ⁻³ μm or more and 1 μm or less. Here, the aluminum oxide film is preferably an Al ₂ O ₃ film.

Hereinafter, an optical modulator device having a plurality of passivation layers according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings, wherein the same or corresponding components are given the same reference numerals regardless of the reference numerals. Duplicate explanations will be omitted. In describing the present invention, when it is determined that the detailed description of the related well-known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, the piezoelectric optical modulator device applied to the present invention will be described first before describing preferred embodiments of the present invention.

1 is a perspective view showing one embodiment of a piezoelectric optical modulator device applicable to a preferred embodiment of the present invention, Figure 2 is a perspective view showing another embodiment of a piezoelectric optical modulator device applicable to a preferred embodiment of the present invention. to be.

1 and 2, a piezoelectric optical modulator device applied to the present invention includes a substrate 110, an insulating layer 120, a sacrificial layer 130, a structure layer 140, and a piezoelectric driver 150. It includes. In addition, a plurality of holes 140 (b) and 140 (d) are provided at the central portion of the structure layer 140. In this case, upper light reflection layers 140 (a) and 140 (c) may be formed on a central portion of the structure layer 140 in which holes are not formed, and lower light may be formed on the insulating layer 120 corresponding to the position of the holes. Reflective layers 120 (a) and 120 (b) may be formed. In addition, the piezoelectric driver 150 controls the structure layer 140 to move up and down in accordance with the degree of contraction or expansion of up and down or left and right caused by the voltage difference between the upper and lower electrodes.

In addition, each part of the optical modulator device will be described in detail in the description of FIG. 5 to be described later. In FIGS. 3 and 4, the optical modulation principle according to the height change between the structure layer 140 and the insulating layer 120 will be described. The explanation is centered.

3 is a plan view of an optical modulator element array including the optical modulator element of FIG. 1, and FIG. 4 is a view for explaining a principle of optical modulation in the optical modulator element array of FIG. 3. 4 is a cross-sectional view taken along line BB ′ of FIG. 3 as a reference line.

Referring to FIG. 3, the optical modulator element array includes the first pixel (pixel # 1), the second pixel (pixel # 2),. And m optical modulator elements 100-1, 100-2,..., 100-m that are responsible for the m-th pixel (pixel #m). The optical modulator element array is responsible for image information of a 1D image of a vertical scan line or a horizontal scan line (assuming that the vertical scan line or the horizontal scan line is composed of m pixels), and each optical modulator element 100-1, 100-2, ..., 100-m) are in charge of any one of m pixels constituting the vertical scan line or the horizontal scan line. Thus, the reflected and diffracted light in each optical modulator element is then projected onto the screen by a light scanning device in a two dimensional image. For example, in the case of VGA 640 * 480 resolution, 640 modulations are performed on one surface of an optical scanning device (not shown) for 480 vertical pixels, thereby generating one frame of one screen per surface of the optical scanning device. Here, the optical scanning device may be a polygon mirror, a rotating bar, a galvano mirror, or the like.

Hereinafter, the principle of light modulation will be described based on the first pixel (pixel # 1), but the same may be applied to other pixels.

In the present embodiment, as shown in FIG. 1, it is assumed that two holes 140 (b)-1 are formed in the structure layer 140. Due to the two holes 140 (b)-1, three upper light reflection layers 140 (a)-1 are formed on the structure layer 140. Two lower light reflection layers are formed in the insulating layer 120 to correspond to the two holes 140 (b)-1. In addition, another lower light reflecting layer is formed on the insulating layer 120 corresponding to the portion of the first pixel (pixel # 1) and the second pixel (pixel # 2). Therefore, the number of upper light reflecting layers 140 (a) -1 and lower light reflecting layers 120 (a) -1 per pixel becomes the same, thereby modulating using zero-order diffraction light or ± first-order diffraction light. The brightness of the light can be adjusted.

Referring to FIG. 4, when the wavelength of light is λ, the distance between the structure layer 140 on which the upper light reflection layer 140 (a) is formed and the insulating layer 120 on which the lower light reflection layer 120 (a) is formed ( A first voltage is applied to the piezoelectric drive body 150 such that 2n) λ / 4 (n is a natural number) (see Fig. 4A). In this case, in the case of the zero-order diffracted light (reflected light), the total path difference between the light reflected from the upper light reflecting layer 140 (a) and the light reflected from the lower light reflecting layer 120 (a) is equal to nλ, which causes constructive interference. The diffracted light has maximum brightness. Here, in the case of + 1st and -1st diffraction light, the brightness of light has a minimum value due to destructive interference.

In addition, the distance between the structure layer 140 on which the upper light reflection layer 140 (a) is formed and the insulating layer 120 on which the lower light reflection layer 120 (a) is formed is (2n + 1) λ / 4 (n is a natural number. Is applied to the piezoelectric drive body 150 (see FIG. 4B). In this case, in the case of the 0th order diffracted light (reflected light), the total path difference between the light reflected by the upper light reflecting layer 140 (a) and the light reflected by the lower light reflecting layer 120 (a) is (2n + 1) λ / As in 2, the destructive light has minimum luminance due to destructive interference. In the case of the + 1st and -1st diffracted light, the luminance of light has a maximum value due to constructive interference.

As a result of such interference, the optical modulator element can load a signal on light by adjusting the amount of reflected or diffracted light. In the above, the distance between the structure layer 140 on which the upper light reflection layer 140 (a) is formed and the insulating layer 120 on which the lower light reflection layer 120 (a) is formed is (2n) λ / 4 or (2n + 1). Although the case of λ / 4 has been described, it will be apparent that various embodiments capable of driving with an interval capable of adjusting the intensity interfered by diffraction or reflection of incident light may be applied to the present invention.

5 is a perspective view showing the structure of an optical modulator device having a plurality of passivation layers according to an embodiment of the present invention, Figure 6 is a cross-sectional view of the optical modulator device having a plurality of passivation layer shown in FIG. In FIGS. 5 to 7, the optical modulator device having two passivation layers and the method of manufacturing the same will be described. However, the optical modulator device having two or more passivation layers and the method of manufacturing the same are shown in the following detailed description. It will be readily appreciated that it can be derived.

In addition, in the following drawings will be described with reference to the optical modulator device having a hole in the center portion of the structure layer 140 as shown in Figure 5, this is only an example and limiting the scope of the invention Of course not. That is, any optical modulator device including a piezoelectric drive body that contracts and expands in accordance with a voltage applied between electrodes in order to implement optical diffraction characteristics to generate a vertical driving force on a ribbon can be used in the present invention. Here, the ribbon is used as a generic term for a predetermined portion of the structure layer 140 that can be moved up and down by the driving force generated by the piezoelectric drive body 150, in this example, the center portion of the structure layer 140 This is the case here.

5 and 6, the optical modulator device according to the present invention includes a substrate 110, an insulating layer 120, a sacrificial layer 130, a structure layer 140, a piezoelectric driver 150, and a passivation layer ( 160).

The substrate 110 is a commonly used semiconductor substrate, and materials constituting the substrate 110 include silicon (Si), alumina (Al ₂ O ₃ ), zirconia (ZrO ₂ ), quartz, and silica (SiO). ₂ ) materials such as these may be used.

The insulating layer 120 is positioned on the substrate 110. The insulating layer 120 serves as an etch stop layer and is a material having a higher selectivity than an etchant for etching the material used as the sacrificial layer 130, where the etchant is an etching gas or an etching solution. Is formed. In this case, the material used as the insulating layer 120 may be silica (SiO ₂ ).

In this case, a lower light reflection layer (for example, 120 (a) of FIG. 1 or 120 (b) of FIG. 2) capable of reflecting or diffracting light may be formed on the insulating layer 120. The lower light reflecting layer may use various light reflecting materials, for example, metal materials (Al, Pt, Cr, Ag, etc.).

The sacrificial layer 130 is positioned on the insulating layer 120. In this case, a material such as silicon (Si) or polysilicon (Poly-Si) may be used as the sacrificial layer 130.

After the sacrificial layer 130 is stacked on the insulating layer 120, some or all of the sacrificial layer 130 may be etched through a process (see FIG. 7F) to be described later. By the etching process, the central portion of the structure layer 140 may be spaced apart by a predetermined interval while securing a driving space between the insulating layer 120 and the insulating layer 120. Here, the driving space means an empty space between the structure layer 140 and the insulating layer 120, the center portion of the structure layer 140, that is, the ribbon is the driving force of the piezoelectric drive body 150 through the secured drive space. It can move up and down correspondingly. In addition, the sacrificial layer 130 that is not removed through the etching process serves to support the structure layer 140.

Here, in the optical modulator device illustrated in FIG. 5, only a part of the sacrificial layer 130 is etched, so that the sacrificial layer 130 is positioned on both side ends of the insulating layer 120 to support the structure layer 140. The layer 130 may be etched in its entirety through a process to be described later (see FIG. 7F). In this case, the sacrificial layer 130 does not support the structure layer 140, but may only serve to secure a driving space in which the structure layer 140 may move up and down. That is, the position of the driving space secured corresponding to the etching process of the sacrificial layer 130 may vary. In addition, when the position of the secured driving space is changed, the position of the ribbon in the structure layer 140 may also be changed accordingly.

The structure layer 140 is positioned on the sacrificial layer 130. In this case, as the structure layer 140, a material of silicon nitride series (Si _X N _Y ) such as Si ₃ N ₄ may be used.

In this case, an upper light reflection layer (for example, 140 (a) of FIG. 1 or 140 (c) of FIG. 2) capable of reflecting or diffracting light may be formed on the center portion of the structure layer 140, that is, the ribbon. have. The upper light reflecting layer may use various light reflecting materials, for example, metal materials (Al, Pt, Cr, Ag, etc.).

In addition, the structure layer 140 may be selectively formed to have a specific shape (in this example, having one or more holes in the center portion of the structure layer 140) through a process to be described later (see FIG. 7F). Can be etched. In this case, the upper light reflection layer is formed at a portion where the hole is not formed in the central portion of the structure layer 140.

The piezoelectric driver 150 is positioned on the structure layer 140. The piezoelectric drive member 150 generates a driving force for allowing the ribbon to move up and down according to the piezoelectric method.

The piezoelectric driver 150 is formed on the lower electrode 151 and the lower electrode 151, and contracts and expands when a predetermined voltage is applied to generate the up and down driving force. And an upper electrode 153 that is formed in the upper electrode 151 to apply a predetermined voltage formed in the piezoelectric layer 152 between the lower electrodes 151.

In this case, platinum (Pt), nickel (Ni), gold (Au), aluminum (Al), titanium (Ti), IrO ₂ , RuO _2, and the like may be used as electrode materials of the lower or upper electrodes 151 and 153. Any one of the above-described combinations of electrode materials may be used. The lower or upper electrodes 151 and 153 may be formed by a method such as sputtering or vacuum evaporation in the range of 0.01-3 μm.

The piezoelectric layer 152 may be formed on the lower electrode 151 in the range of 0.01 to 20.0 μm by wet (screen printing, Sol-Gel coating, etc.) and dry methods (sputtering, Evaporation, MOCVD, Vapor Deposition, etc.). As the piezoelectric layer 152, piezoelectric materials such as PZT, PNN-PT, PLZT, AlN, and ZnO may be used, and elements such as lead (Pb), zirconium (Zr), zinc (Zn), or titanium (Ti) may be used. It is also possible to use a piezoelectric electrolytic material comprising one or more.

The passivation layer 160 is positioned on the piezoelectric driver 150, that is, on the upper electrode 153. The passivation layer 160 illustrated in FIG. 5 has a two-layer structure. After the first passivation layer 161 is stacked, the second passivation layer 162 is stacked on the first passivation layer 161. The passivation layer 160 serves to protect the piezoelectric driver 150 from moisture absorption of ambient moisture generated in the manufacturing process of the optical modulator device. More specifically, the first passivation layer 161 serves to directly protect the upper electrode 153 and the piezoelectric layer 152 of the piezoelectric driver 150 from moisture absorption and permeation of hydrogen, The second passivation layer 162 serves to indirectly protect the piezoelectric driver 150 by protecting the first passivation layer 161 to prevent the characteristic change of the first passivation layer 161.

To this end, in the present invention, a silicon oxide film (eg, SiO _2, etc.) is used as the first passivation layer 161, and an aluminum oxide film (eg, Al ₂ O _3, etc.) is disposed on the first passivation layer 161. Are used as the second passivation layer 162. Here, the aluminum oxide film (for example, Al ₂ O _3, etc.) used as the second passivation layer 162 is excellent in moisture absorption prevention function. Therefore, the second passivation layer 162 may form a stronger passivation layer by reducing the stress change of the film due to moisture absorption, which may occur when using a single passivation layer composed of only a silicon oxide film (eg, SiO ₂ ). To help. As a result, it is possible to prevent the change (malfunction) of the operating characteristics of the piezoelectric drive body 150 and also to shorten the life of the piezoelectric drive body 150.

At this time, the thicknesses of the first and second passivation layers 161 and 162 are preferably 10 ⁻³ μm or more and 1 μm or less, respectively. Here, the lower limit (10 ^-3 mu m) is set to the minimum thickness at which the first and second passivation layers 161 and 162 can serve as passivation layers, respectively, and the upper limit (1 mu m) is the overall passivation layer. The thickness of the passivation layer determined to be appropriate in consideration of the characteristics of the thin film and the yield in the manufacturing process of the thin film is set. That is, a range that can prevent disadvantages such as difficulty in manufacturing process and increase of film stress that occurs when the passivation layer becomes too thick is selected.

In this case, the first and second passivation layers 161 and 162 may be a deposition method such as CVD, PECVD, ALD. In particular, an ALD (Atomic Layer Deposition) deposition method is preferable as a deposition method of an aluminum oxide film (for example, Al ₂ O _3, etc.) used as the second passivation layer 162. The ALD deposition method is an advantageous method for depositing an ultrathin film by using chemical adsorption and desorption processes between materials to be deposited, and it is possible to form a film having a uniform thickness even if the area of the substrate to be deposited is large. Because of this.

As described above, the present invention can further improve the optical diffraction characteristics and reliability of the entire optical modulator device by improving the operating characteristics of the piezoelectric driver 150 through the plurality of passivation layers 160.

FIG. 7 is a cross-sectional view illustrating a manufacturing process of an optical modulator device having a plurality of passivation layers shown in FIG. 5.

Referring to FIG. 7A, an insulating layer 120 is formed on the substrate 110. The insulating layer 120 serves as an etch stop layer.

Referring to FIG. 7B, a sacrificial layer 130 is formed on the insulating layer 120. Here, the sacrificial layer 130 may be etched in part or in whole so that the ribbon may secure a driving space through a later process (see FIG. 7F) and may be spaced apart from the insulating layer 120 by a predetermined distance. .

Referring to FIG. 7C, the structure layer 140 is formed on the sacrificial layer 130. The structure layer 140 may be selectively etched to form a specific shape (eg, a shape having one or more holes) through a later process (see FIG. 7F).

Referring to FIG. 7D, the piezoelectric driver 150 is formed on both side ends of the structure layer 140. The piezoelectric driver 150 stacks a lower electrode 151 on the structure layer 140, a piezoelectric layer 152 on the lower electrode 151, and an upper electrode 153 on the piezoelectric layer 152. ) And the upper electrode 153 and the piezoelectric layer stacked on portions except the upper electrode 153, the piezoelectric layer 152, and the lower electrode 151 stacked on both side ends of the structure layer 140. The 152 and the lower electrode 151 are formed by etching.

However, unlike the case of the optical modulator device illustrated in FIG. 7, the piezoelectric driver 150 may be formed on the entire surface of the structure layer 140 instead of on both sides of the structure layer 140, in which case Of course, one etching process may be unnecessary.

In addition, although not shown in FIG. 7, between the upper portion of the structure layer 140 and the lower portion of the lower electrode 151 in order to protect the upper portion of the structure layer 140 positioned on the lower surface thereof during the etching of the lower electrode 151. Forming a SiO ₂ layer of a certain thickness may be further included.

Referring to FIG. 7E, the passivation layer 160 is formed on the piezoelectric driver 150. The passivation layer 160 has a two-layer structure and is formed by stacking the first passivation layer 161 and then laminating the second passivation layer 162 on the first passivation layer 161.

Referring to FIG. 7F, the sacrificial layer 130 may be spaced apart from the insulating layer 120 by a predetermined space by an etchant (where the etchant is an etching gas or an etching solution) to secure a driving space. Some or all of them are etched so that they can be etched.

In this case, a process of selectively etching the structure layer 130 may be preceded by an etching process of the sacrificial layer 130. That is, in this example, an etching process of forming a plurality of holes in the ribbon is preceded by an etching process of the sacrificial layer 130, and in this case, the etching process of the sacrificial layer 130, which is subsequently performed, is a holo etchant formed in the ribbon. It can be done by the method of injecting.

8 is a cross-sectional view of an optical modulator device having a plurality of passivation layers according to another preferred embodiment of the present invention. In the optical modulator of FIG. 8, a third passivation layer 163 is further formed between the piezoelectric driver 150 and the first passivation layer 161 of the optical modulator of FIG. 5.

That is, the optical modulator device of FIG. 8 includes three passivation layers, and a person skilled in the art will appreciate that a third passivation layer (161) may be formed before the first passivation layer 161 is stacked on the upper electrode 153 of the piezoelectric driver 150. It will be readily appreciated that stacking 163 is feasible.

As the third passivation layer 163, an aluminum oxide film (eg, Al ₂ O ₃ or the like) as in the second passivation layer 162 may be used. That is, the second and third passivation layers 162 and 163 composed of aluminum oxide films excellent in moisture absorption prevention and the like are formed of silicon oxide films (eg, SiO _2, etc.) constituting the first passivation layer 161. By protecting the upper and lower portions in the form of a sandwich, a stronger passivation layer is formed.

As described above, according to the optical modulator device having the plurality of passivation layers and the method of manufacturing the same, malfunction of the piezoelectric drive body due to ambient moisture absorption or the like can be minimized through the plurality of passivation layers including the aluminum oxide film. . Through this, the degradation of the operating characteristics of the piezoelectric drive body can be prevented and the life of the piezoelectric drive body can be prevented from being shortened.

In addition, by preventing degradation of the piezoelectric drive body, the height of the gap between the ribbon and the insulating layer in the optical modulator device can be kept constant, thereby maximizing the optical diffraction characteristics and reliability of the entire optical modulator device. There is.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art that various modifications of the present invention without departing from the spirit and scope of the invention described in the claims below And can be changed.

Claims (10)

Board; An insulating layer on the substrate; A structure layer having a central portion spaced apart from the insulating layer by a predetermined distance; Located on the structure layer, the piezoelectric drive body for moving the central portion of the structure layer up and down; A first passivation layer on the piezoelectric driver and protecting the piezoelectric driver; And A second passivation layer located on the first passivation layer and protecting the first passivation layer Optical modulator device having a plurality of passivation layer comprising a. The method of claim 1, Further comprising a sacrificial layer positioned on the upper portion of the insulating layer and the lower portion of the structure layer, and supporting the structure layer, The sacrificial layer has a plurality of passivation layer having a portion of the structure layer is disposed on the lower surface of the center portion is etched so as to be spaced apart from the insulating layer by the predetermined interval. The method of claim 1, The piezoelectric drive body Lower electrode; A piezoelectric layer disposed on the lower electrode and contracting and expanding according to a predetermined voltage to generate a vertical driving force in a central portion of the structure layer; And An upper electrode disposed on the piezoelectric layer and applying the predetermined voltage formed in the piezoelectric layer between the lower electrodes; Optical modulator device having a plurality of passivation layer comprising a. The method of claim 1, And a third passivation layer disposed on an upper portion of the piezoelectric driver and a lower portion of the first passivation layer, the third passivation layer protecting the piezoelectric driver. The method of claim 4, wherein And the third passivation layer has a plurality of passivation layers which are Al ₂ O ₃ films. The method according to any one of claims 1 to 4, And the first passivation layer has a plurality of passivation layers which are SiO ₂ films. The method of claim 6, And a first passivation layer having a plurality of passivation layers having a thickness of 10 ⁻³ μm or more and 1 μm or less. The method according to any one of claims 1 to 4, And the second passivation layer has a plurality of passivation layers which are aluminum oxide films. The method of claim 8, And a second passivation layer having a plurality of passivation layers having a thickness of 10 ⁻³ μm or more and 1 μm or less. The method of claim 8, The aluminum oxide film is an optical modulator device having a plurality of passivation layer is an Al ₂ O ₃ film.

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