CN1204434C

CN1204434C - Method for manufacturing thin film actuated mirror array

Info

Publication number: CN1204434C
Application number: CN 97182217
Authority: CN
Inventors: 闵庸基
Original assignee: Daewoo Electronics Co Ltd
Current assignee: WiniaDaewoo Co Ltd
Priority date: 1997-05-27
Filing date: 1997-05-27
Publication date: 2005-06-01
Anticipated expiration: 2017-05-27
Also published as: CN1254479A

Abstract

The present invention relates to a method for manufacturing an array of a thin film actuating reflector (401) in an optical projection system. The method comprises the procedures: a base (310) is arranged; a thin film layer to be removed is deposited on the base; an array of M*N cavities is generated on the thin film layer to be removed; an elastic layer is deposited on the top of the thin film layer to be removed, which comprises cavities; an array of M*N flexible components (335) is configured by the elastic layer; an array of M*N switching devices (415) is formed on the base; a passivating layer (340) and an etchant stopping layer (350) are deposited on the top of each flexible component and each switching device; the passivating layers and the etchant stopping layers are selectively removed, so that the flexible components are exposed; an array of M*N second thin film electrodes (365) and an array of M*N thin film electrode displacement parts (375) are continuously formed on the top of each flexible component; an array of M*N first thin film electrodes and an array of contact parts are formed; the thin film layer to be removed is removed, and thereby, an array of M*N actuating mechanisms is formed; material to be removed covers the array of M*N actuating mechanisms; a reflector layer is deposited on the top of the material to be removed, and an array of M*N reflectors is configured by the reflector layer; the material to be removed is removed, and thereby, an array of M*N thin film actuating reflectors is formed. In order to prevent the thermal damage of an active matrix, in the method of the present invention, after all high temperature treatment is completed, the array of M*N switching devices (415) is formed on the base (310), and thereby, the possibility of the thermal damage which occurs on the array of switching devices (415) is reduced.

Description

Manufacture the method for array of thin film actuated mirrors

Technical field

The present invention relates to a kind of M * N array of thin film actuated mirrors that is used for optical projection system; And more specifically, relate to a kind of method that is used to manufacture array of thin film actuated mirrors, the influence of the pyroprocessing that it has comprised in having reduced to manufacture.

Background technology

In the various video display systems of prior art, known a kind of optical projection system can provide significantly high-quality display.In such optical projection system, for example be radiated at equably on one M * N actuated mirror array from the light of a lamp, wherein each catoptron is connected with each actuator.These actuators can put on its electric field and the electricity that is out of shape causes the displacement material makes by response.For example be piezoelectric or electrostriction material.

Be incident on from the folded light beam of each catoptron on the aperture of a diaphragm for example.By each actuator is applied an electric signal, the relative position of each catoptron and incident beam is changed, thereby causes deflecting from the light path of the folded light beam of each catoptron.When the light path of each folded light beam changes, the light quantity of passing through this aperture from each mirror reflects is changed, thereby the intensity of modulated beam of light, by the modulated light beam of this aperture through suitable optical devices for example a projecting lens be sent on the projection screen, thereby show an image thereon.

In Figure 1A to 1I, show a total pending application, international application no PCT/KE96/00142, be entitled as in " array of thin film actuated mirrors that is used for optical projection system " disclosed, manufacture the step of manufacturing that comprises in the array 200 of M * N thin-film actuated reflection mirror 201, wherein M and N are integers.

This processing of manufacturing array 200 starts from preparing an active matrix 110, and it comprises that one has M * N switchgear, for example the substrate 112 of the array of metal-oxide semiconductor (MOS) (MOS) transistor 115 and a field oxide layer 116 that is formed on its top.Each MOS transistor 115 has one source/drain region 117, one gate oxide layers 118 and gate pole 119.

In following step, on the top of active matrix 110, deposit first passivation layer of making by for example PSG or silicon nitride 120 with 0.1-2 μ m thickness by for example using CVD or spin coating method.

Then, on the top of first passivation layer 120, deposit an etchant trapping layer 130 of making by nitride by using for example sputter or CVD method, shown in Figure 1A with 0.1-2 μ m thickness.

Then, on the top of this etchant trapping layer 130, form a film and wait to remove layer 140.If this film is waited to remove layer 140 and is made of metal, wait to remove layer 140 by using sputter or vapour deposition method to form this film, make by PSG, use CVD or spin coating method if this film waits to remove layer 140, if or this film waits to remove layer 140 and made by silicon polymer (poly-Si), use the CVD method.

Then, do or wet etch method, wait to remove generation one M * N array of cavities (not shown) on the layer 140 so that each cavity centers on the source/drain region 117 in each MOS transistor 115 at this film by this way by using.

In next step, by using CVD method the posterior limiting 150 that deposition is made by the insulating material of for example silicon nitride on this film that comprises these cavitys is treated except that the top of layer 140 with 0.1-2 μ m thickness.

Then, by using sputter or vacuum vapour deposition on the top of this elastic layer 150, to form second thin layer of making by the conductive material of for example Pt/Ta 160 with 0.1-2 μ m thickness.Then by using an etching method along this second thin layers 160 of cutting such as column directions, shown in Figure 1B.

Then, by use evaporation, Sol-Gel, sputter or CVD method on the top of this second thin layer 160, deposit by the piezoelectric of for example PZT or for example the thin-film electro made of the electrostriction material of PMN with 0.1-2 μ m thickness cause the displacement layer (not shown).

Then, be configured to M * N thin-film electro and cause an array of displacement component 175 by using photoetching process or laser pruning method that this thin-film electro is caused displacement layer, shown in Fig. 1 C.

In the step of following, by using etching method second thin layer 160 and this elastic layer 150 are configured to an array of M * N second membrane electrode 165 and an array of M * N elastomeric element 155 respectively, shown in Fig. 1 D.

In the step of following, by the etchant trapping layer 130 on the top of using an etching method to remove to be formed on the source/drain region 117 in each MOS transistor 115 and the part of first passivation layer 120, stay their gate poles 119 in each MOS transistor 115 and the part 125 of not touching of door oxide layer 118 simultaneously, shown in Fig. 1 E.

Then, form M * an array of N the first film electrode 185 and an array of contact component 183: at first use sputter or vacuum vapour deposition to form and make, cover one deck (not shown) of said mechanism fully by conductive material by following steps; Then use etching method selectively to remove this layer, shown in Fig. 1 F.Each the first film electrode 185 is positioned in this thin-film electro and causes on the top of displacement component 175.Each contact component 183 is so positioned so that it is electrically connected second membrane electrode 165 with source/drain region 117 in each MOS transistor 115.

In following steps, by second passivation layer 187 that uses CVD or spin coating method deposition to make with 0.1-2 μ m thickness by for example PSG or silicon nitride, and then by use etching method like this with its configuration so that it covers these contact components 183 fully, thereby form an array 210 of M * N actuated mirror mechanism 211, shown in Fig. 1 G.

Cover each actuated mirror mechanism 211 fully with the first film protective seam (not shown) then.

Wait to remove layer 140 by using etching method to remove this film then.Then, remove the first film protective seam, thereby form an array of M * N actuating mechanism 100, each actuating mechanism 100 has a near-end and far-end (not shown), shown in Fig. 1 H.

In next step,, comprise that the interval that forms is so that the top of resulting mechanism (not shown) is fully smooth when this film waits that removing layer 140 is removed like this with waiting to remove the array that material covers M * N actuating mechanism 100.Then, generate an array (not shown) of M * N dead slot by using photoetching process in this mechanism that obtains, each dead slot extends to the top of the far-end of each actuating mechanism 100 from the top of this mechanism that obtains.

After above-mentioned steps, sequence ground is waited to remove material at this and is comprised that deposition is by reflectorized material on the top of these dead slots, a mirror layer (not shown) and the thin-film dielectric layer (not shown) made of Al for example, and then by using photoetching process or laser pruning method respectively this mirror layer and this thin-film dielectric layer to be configured to an array of M * N catoptron 190 and an array of M * N thin-film dielectric parts 195, thereby form M * N semi-manufacture actuated mirror array (not shown), wherein each catoptron 190 has a recessed portion 197, and this recessed portion 197 is connected on the top of far-end of actuating mechanism 100.

Cover each semi-manufacture actuated mirror fully with the second thinfilm protective coating (not shown) then.

Wait to remove material by using etching method to remove this then.Then, remove this second thinfilm protective coating, thereby form the array 200 of this M * N thin-film actuated reflection mirror 201, shown in Fig. 1 I.

The method of the array 200 of the above-mentioned M of manufacturing * N thin-film actuated reflection mirror 201 has some defective.For example, this method comprises a plurality of pyroprocessing, during the stage, for example form the elastic layer of being made by nitride 140 and require minimum 800 ℃ temperature, and active matrix 110 can not bear such high temperature usually, causes its fire damage especially in early days.

Summary of the invention

Therefore, the object of the present invention is to provide a kind of method that is used for manufacturing the array of thin film actuated mirrors that is used for optical projection system, the effect of the pyroprocessing that it has comprised in having reduced to manufacture.

According to the present invention, provide a kind of method of manufacturing the array of thin film actuated mirrors that is used for optical projection system, this method includes step: a substrate is set; Deposition one film waits to remove layer on the top of this substrate; Wait to remove an array that generates M * N cavity on the layer at this film; Waiting to remove layer at this film comprises on the top of these cavitys and deposits posterior limiting; This elastic layer is configured to an array of M * N elastomeric element; In this substrate, form an array of M * N switchgear; Deposition one passivation layer and an etchant trapping layer on the top of each elastomeric element and switchgear; Selectively remove this etchant trapping layer and this passivation layer so that these elastomeric elements are exposed out; An array and the M * N thin-film electro that form M * N second membrane electrode continuously on the top of each elastomeric element cause an array of displacement component; Form M * an array of N the first film electrode and an array of contact component; Remove this film and wait to remove layer, thereby form an array of M * N actuating mechanism; Wait to remove the array that material covers this M * N actuating mechanism with one; Wait to remove deposition one mirror layer on the top of material at this; This mirror layer is configured to an array of M * N catoptron; And remove this and wait to remove material, thereby form this M * N array of thin film actuated mirrors.

Description of drawings

By the following drawings description of preferred embodiments, above and other purpose of the present invention and feature will become obviously, in the accompanying drawing:

Figure 1A to 1I has provided the previous disclosed summary cross sectional view that is used to manufacture a method of M * N array of thin film actuated mirrors of explanation; And

Fig. 2 A to 2J has provided explanation according to the summary cross sectional view that is used to manufacture a method of M * N array of thin film actuated mirrors of the present invention.

Embodiment

Fig. 2 A to 2J has provided the summary cross sectional view of explanation according to a method of an array 400 of manufacturing M * N thin-film actuated reflection mirror 401 of being used for an optical projection system of the present invention.Should notice that the same parts that occurs among Fig. 2 A to 2J represents with identical reference number.

This processing of manufacturing array 400 starts from preparing substrate 310, for example a silicon chip of being made by insulating material.

In next step, on the top of substrate 310, form a film and wait to remove layer 320.If this film is waited to remove layer 320 and is made of metal, wait to remove layer 320 by using sputter or vapour deposition method to form this film, make by PSG, use CVD or spin coating method if this film waits to remove layer 320, if or this film waits to remove layer 320 and made by silicon polymer (poly-Si), use the CVD method.

Then, do or wet etch method, wait to remove an array that generates M * N cavity 325 on the layer 320 at this film, shown in Fig. 2 A by using.

In next step, by using CVD method the posterior limiting (not shown) that deposition is made by the insulating material of for example nitride on this film that comprises these cavitys is treated except that the top of layer 320 with 0.1-2 μ m thickness.

At next step, by using the etching method under 800 ℃ high temperature for example this elastic layer is configured to an array of M * N elastomeric element 335, shown in Fig. 2 B.

Then, in substrate 310, form M * N switchgear 415, for example the transistorized an array of metal-oxide semiconductor (MOS) (MOS).Each MOS transistor 415 has one source/drain region 417, one gate oxide layers 418 and a gate pole 419 and is positioned between the elastomeric element 335 in succession of two in the same row or column, shown in Fig. 2 C.

In following step, on the top of each elastomeric element 335 and switchgear 415, deposit first passivation layer of making by for example PSG or silicon nitride 340 with 0.1-2 μ m thickness by for example using CVD or spin coating method.

Then, on the top of first passivation layer 340, deposit an etchant trapping layer 350 of making by nitride by using for example sputter or CVD method, shown in Fig. 2 D with 0.1-2 μ m thickness.

In the step of following, remove the part of the etchant trapping layer 350 and first passivation layer 340 by using an etching method, stay the part 345 of not touching simultaneously, shown in Fig. 2 E.

Then, by using sputter or vacuum vapour deposition on the top of each elastomeric element 335, to form the second thin layer (not shown) of making by the conductive material of for example Pt/Ta with 0.1-2 μ m thickness.Then by using an etching method along this second thin layers of cutting such as column directions.

Then, by use evaporation, Sol-Gel, sputter or CVD method on the top of this second thin layer, deposit by the piezoelectric of for example PZT or for example the thin-film electro made of the electrostriction material of PMN with 0.1-2 μ m thickness cause the displacement layer (not shown).

Then, be configured to M * N thin-film electro respectively and cause an array of displacement component 375 and an array of M * N second membrane electrode 365 by using photoetching process or laser pruning method that this thin-film electro is caused displacement layer and second thin layer, shown in Fig. 2 F.

Then, form M * an array of N the first film electrode 385 and an array of contact component 383: at first use sputter or vacuum vapour deposition to form and make, cover one deck (not shown) of said mechanism fully by conductive material by following steps; Then use etching method selectively to remove this layer, shown in Fig. 2 G.Each the first film electrode 385 is positioned in this thin-film electro and causes on the top of displacement component 375.Each contact component 383 is so positioned so that it is electrically connected second membrane electrode 365 with source/drain region 417 in each MOS transistor 415.

In following steps, by second passivation layer 387 that uses CVD or spin coating method deposition to make with 0.1-2 μ m thickness by for example PSG or silicon nitride, and then by use etching method like this with its configuration so that it covers these contact components 383 fully, thereby form an array 420 of M * N actuated mirror mechanism 421, shown in Fig. 2 H.

Cover each actuated mirror mechanism 421 fully with the first film protective seam (not shown) then.

Wait to remove layer 320 by using etching method to remove this film then.Then, go this to remove the first film protective seam, thereby form an array of M * N actuating mechanism 300, each actuating mechanism 300 has a near-end and far-end (not shown), shown in Fig. 2 I.

In next step,, comprise that the interval that forms is so that the top of resulting mechanism (not shown) is fully smooth when this film waits that removing layer 320 is removed like this with waiting to remove the array that material covers M * N actuating mechanism 300.Then, generate an array (not shown) of M * N dead slot by using photoetching process in this mechanism that obtains, each dead slot extends to the top of the far-end of each actuating mechanism 300 from the top of this mechanism that obtains.

After above-mentioned steps, sequence ground is waited to remove material at this and is comprised that deposition is by reflectorized material on the top of these dead slots, a mirror layer (not shown) and the thin-film dielectric layer (not shown) made of Al for example, and then by using photoetching process or laser pruning method respectively this mirror layer and this thin-film dielectric layer to be configured to an array of M * N catoptron 390 and an array of M * N thin-film dielectric parts 395, thereby form M * N semi-manufacture actuated mirror array (not shown), wherein each catoptron 390 has a recessed portion 397, and this recessed portion 397 is connected on the top of far-end of actuating mechanism 300.

Wait to remove material by using etching method to remove this then.Then, remove this second thinfilm protective coating, thereby form the array 400 of this M * N thin-film actuated reflection mirror 401, shown in Fig. 2 J.

Opposite with the previous disclosed method that is used to manufacture M * N array of thin film actuated mirrors, in the method for the invention, after all pyroprocessing are finished, in substrate 310, form an array of M * N switchgear 415, and then reduced the possibility of the fire damage that on the array of this switchgear 415, occurs.

Although the present invention is illustrated and describes with reference to specific embodiment, obviously do not break away from the spirit and scope of the present invention that are defined by the following claims, those skilled in the art can make many variations and remodeling.

Claims

1, a kind of method of manufacturing the array of thin film actuated mirrors that is used for optical projection system, this method includes step:

One substrate is set;

Deposition one film waits to remove layer on the top of this substrate;

Wait to remove an array that generates M * N cavity on the layer at this film;

Waiting to remove layer at this film comprises on the top of these cavitys and deposits posterior limiting;

This elastic layer is configured to an array of M * N elastomeric element;

In this substrate, form an array of M * N switchgear;

Deposition one passivation layer and an etchant trapping layer on the top of each elastomeric element and switchgear;

Selectively remove this etchant trapping layer and this passivation layer so that these elastomeric elements are exposed out;

An array and the M * N thin-film electro that form M * N second membrane electrode on the top of each elastomeric element cause an array of displacement component;

Form M * an array of N the first film electrode and an array of contact component;

Remove this film and wait to remove layer, thereby form an array of M * N actuating mechanism;

Wait to remove the array that material covers this M * N actuating mechanism with one;

Wait to remove deposition one mirror layer on the top of material at this;

This mirror layer is configured to an array of M * N catoptron; And

Remove this and wait to remove material, thereby form this M * N array of thin film actuated mirrors,

Wherein said switchgear array is just to form after all pyroprocessing are finished.

2, according to the process of claim 1 wherein that this substrate made by insulating material.

3, according to the method for claim 2, wherein this substrate is a silicon chip.

4, according to the process of claim 1 wherein that each switchgear is a metal-oxide semiconductor (MOS) (MOS) transistor.

5, according to the process of claim 1 wherein that each switchgear is positioned between the elastomeric element in succession of two in the same row or column.

6, according to the method for claim 1, also include step: forming thin-film dielectric parts on the top at each catoptron behind this mirror layer of deposition.