TW200411694A - Electrostatic-driving micro relay and manufacturing method thereof - Google Patents

Abstract

The present invention relates to an electrostatic-driving micro relay and a manufacturing method thereof. In the present invention, a complementary metal oxide semiconductor (CMOS) process is first applied on a silicon chip to produce an elementary structure of the micro relay before applying post processes, including wet chemical etching and electro-less plating, to complete the manufacturing of the micro relay. Such a method can be mutually integrated with the integrated circuit process for mass production and, since no reticle is required in the post processes, it can significantly simplify the whole manufacturing process and help reducing the manufacturing cost.

Description

200411694 Description of the invention α) [Technical field to which the invention belongs] The present invention relates to an electrostatically driven micro-relay and a method for manufacturing the same, and more particularly to an electrostatically driven device manufactured using a complementary metal-oxide semiconductor process and micromachining method. Micro relay and its manufacturing method. [Previous technology] ~ In recent years, 'micro-electro-mechanical-system (MEMS) technology has become increasingly mature due to the advancement of microfabrication technology and the advancement of semiconductor process technology'. And because the components produced by MEMS technology have the advantages of (丨) tiny = (2) low power consumption (3) high-frequency response (4) low cost, this technology is widely used in different In the production of different components in the field, such as: micro accelerators, micro shutters, micro forceps, micro aircraft, biomedical wafers, etc. For example, at present, a large number of Micro Relays are used in semiconductor circuit testing, and are automatically tested in the second type, and the Micro Relays in ^ tomated Test Equipment (ATE) have high isolation. , Low leakage current (i〇w ieakage current), high frequency switching (high switching time) and low output capacitance (low 〇utput CHaPTC i tance) characteristics, so most of the micro-relays currently developed 疋 purely use micro-electromechanical Made by technology. Mimio Micro-relays based on 4-electromechanical processes have been developed, and most of the driving methods are driven by electrostatic forces. Electrostatically driven micro-relays disclosed in U.S. Patent Nos. 6, 3 96, 3 72. First, electrodes are made on one substrate and then made on another substrate. Page 6 200411694

Each movable contact is then bonded to a substrate using a wafer bonding method to form a movable structure. However, the use of a micro-processing process to produce a micro-relay on a substrate is complicated in overall production and difficult to integrate with the integrated circuit nntegFate (i Circuit; IC) process, so a large number of π cannot be performed. Another disadvantage is that the micro-relay made using this method = only one structure, so after the structure is manufactured, you need another: the drive to drive the micro-relay, or other The matching = sub-package circuit can be combined with this structure to produce the function of a micro-relay. In this way, the complexity of the overall structure is increased. [Summary of the Invention] "In view of the problems of the conventional technology, the object of the present invention is to provide an electrostatically driven micro-relay and a manufacturing method thereof. The existing complementary metal oxide semiconductor process (Complementarr Metal Oxide

(Semlconductor; CMOS) to produce a micro-relay structure, combined with micromachining technology. This method can completely integrate with the integrated circuit for mass production, and in the post-processing process (p0st_pr〇cess), it does not need to use the mask alignment action, only wet etching and E1 ectr ο 1 essp 1 ating technology can effectively simplify the process and help reduce manufacturing costs. The electrostatically driven micro-relay developed by the invention and its manufacturing method use silicon wafers as a substrate and use complementary metal-oxide semiconductor manufacturing processes to produce the required structure. Next, the plug layer originally lost in the middle of the two metal layers is used as a sacrificial layer, and is etched away by a wet chemical etching method.

200411694 V. Description of the invention (3) This interlocking layer releases the structure above it to form / suspend the structure. After the metal layer on the output line is plated with metal-to-metal contact, and the structure is made of the electric pole, the electrodeless mining technology is used. 1 The floating structure and the input signal line (input 1 i ne) and output signal gold (gold) to form the final, and then by applying a DC voltage to the metal layer on the silicon wafer and the metal layer suspended f junction ^, electrostatic force is generated between the two, the suspension structure ^ ΐ two The input signal is formed into a loop by the metal layer on the suspended structure and the output signal; by controlling the DC voltage to open or close it is eight i, Γ The suspended ocean structure and the structure below it are contact with each other or the knife is Building i completes the control of current conduction or non-conduction in the micro relay. Understanding ΐ :: ,, the structural features and their functions have been advanced [.Implementation "Wide " The detailed description is as follows: According to the invention disclosed by Xia—, The skin method, * The micro-relays and components of the micro-relays with complementary electric drive are applied. The first solid wire of the present invention is manufactured by the semiconductor process and micro-processing technology. Metal Oxygen First, as shown in "FIG. 2 in a post-process system, which follows the manufacturing process: a metal layer (Metal 1) 10 ^ ^ long first layer is an aluminum alloy layer on the silicon chip 10〇 ί. Next, the material of the metal layer 101 may be aluminum or 102. The first insulating layer is equal to the length of the first insulating layer on the two metal layer 101. The material may be silicon dioxide (Si02). , Or

Page 8 200411694 V. Description of the invention (4) Other insulating materials, and this silicon wafer with an insulating layer 100, the first metal layer 101, and the first insulating layer 102 constitute the micro-relay. The substrate portion. : ,, after, a second metal layer (μ eta 1 /, material is ming or ming alloy, and the input terminal (input! Ne) l〇3a is defined on the brother and the 纟 ba line layer 〇2 And the output terminal (〇ι1ΐρι1ΐ Une) i〇3b, which is divided into two input terminals 103a and output terminal 103b are used as external signal input and output channels. Next, in the second metal layer The upper layer of pin layer (piug) y4er 1 04. The material of this pin layer 104 can be an interlayer of tungsten and titanium, and this layer of pin layer 104 is used in this structure as a sacrificial layer basin: after all the structures are completed The% can be engraved with wet chemical money method to form the suspended junction straight material required in the micro-relay: Ϊ lock layer 1 〇4 a third metal layer (M❿ ") 1 〇5 The material can be Ma Ming or | Lu He, > The suspension structure includes the contact surface 105 & and: the shape of the structure. This surface 105a is wet-typed; J touches the contact part of the wheel output end 103b. Therefore, when: TΓ, α structure and input terminal 103a The part of the cantilever beam 105b is connected to the lower part to support the suspension structure. In addition to defining the connection between the first layer and the second layer, the position of the pad (Pad) must be defined in order to give the shape of the structure. Position. In addition, you need to add the exposed pin and circuit cut pin layer 104 to make it easier

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The subsequent wet chemical etching is performed. Finally, after each metal layer and insulation layer below are made, a protective layer (P as S ivati on) layer 106 is grown on the top of the suspension structure. This protective layer 106 is made of silicon oxide and nitrogen. It is composed of silicon and its function is to protect the underlying structure from damage or oxidation. For example, the complementary metal-oxide semiconductor process is completed. Next, as shown in "Figure 2", the plug layer 104 is etched away by a wet chemical etching method, so that the floating structure and the protective layer 10 above it are suspended above the input terminal 103a and the output terminal 103b. , That is, to complete the preliminary fabrication of the micro-relay structure. Since the above-mentioned pin layer 丨 04 is made of tungsten and titanium " its materials', therefore, hydrogen peroxide is used as an etching solution for chemical etching to completely etch the pin layer 104 without damaging other metal layers and insulation structures. . The method of controlling the current on or off of the micro-relay is to apply a DC voltage to the first metal layer 101 on the silicon wafer and the third metal layer 105 in the floating structure, so that An electrostatic force is generated between the two, which attracts the suspension structure, and comes into contact with the input terminal 103 and the output terminal 103b of the second metal layer 103 to form metal-to-metal contact.

The signal line at the input end 103a is contacted by the contact surface 5 a on the suspension structure and the output signal line at the output end 1 q 3 b is contacted to form a current loop; by controlling the state of the DC voltage on or off, Suspended junctions, the input terminal 103 and the output terminal 103b are in contact or separated from each other, that is, the control of current conduction or non-conduction in the micro-relay is completed. However, as external current passes through the micro-relay,

Page 10 200411694 V. Description of the invention (6) The part (the input terminal 103a, the third metal layer 105 and the output terminal 103b) is aluminum or aluminum alloy, which has a large resistance value, and external signals are input to this micro-relay. After the loss of energy is more, less desirable. Therefore, in order to reduce the resistance value of the part of the metal in contact with the first metal layer 103 in the floating structure, after the wet chemical etching step, the electrodeless plating method is used, as shown in "Figure 3". The upper surface of the input terminal 103 and the output terminal 103 of the second metal layer 103 and the lower surface of the third metal layer 105 are plated with a layer of nickel, and then a layer of gold is plated, With the formation of the first contact layer 丨 i and the second contact layer 112 respectively, the fabrication of the entire micro-relay is completed. For the completed perspective view, please refer to "Figure 4". The use of gold as the metal part through which the current passes can effectively reduce the resistance and has the advantage of not being easily oxidized. It is a good choice of contact layer material. The second embodiment of the present invention is similar to the first embodiment. Please refer to "Figure 5" for a cross-sectional view of the complementary metal-oxide-semiconductor process after the completion of the conventional example. The last step in the process is to grow a protective layer 106 on the suspension structure. The first embodiment is to extend a protective layer on the entire suspension structure. 06, and the second embodiment is to the suspension structure. The clock has a layer of nickel and gold. In the first embodiment, the protective layer 10 (composed of silicon oxide and silicon nitride) is above the third metal layer 105, and this layer is the protective layer 106 in the complementary metal-oxide semiconductor process. . In the second embodiment, there is no such protective layer 10 above the first layer 105. After the entire suspension structure is released, only the third metal layer 105 remains. However, in the first contact of plating, Layer 丨 丨} and the second contact layer 112, the upper and lower surfaces of the third metal layer 丨 05 will be plated.

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Nickel and gold. "Picture"-use wet chemical method to cut off the layer 104 money, make the top pin structure by the third H method, the county floats in the entrance #] Λ < 3 "= The suspended junction formed by _ 105 is weighed on the input terminal 103a and the output terminal 1031}, and the structure of the micro-relay is made. The above is preliminary because the above-mentioned pin layer 104 is chemically etched with hydrogen peroxide using tungsten. It is oblique, and the majority is its material, so it is etched away without using the liquid 5 to complete the pin layer 104, and then the structure of the metal layer and the insulating layer. The first input end 103a and the first The surface of the end view is facing; the upper and lower surfaces are plated with nickel on the top and bottom, and then the surface is cut into = to 'respectively the input terminal 103a and the outlet 103b.

The first contact layer of the clothing song formation, Chu — J, the second contact layer 112, and the surface of the metal layer 105 below the metal layer 105 forms the metal layer 113, and the surface of the metal layer 105 above the metal layer 105 forms a protection. As shown in gold. The use of full " relays, the three-dimensional diagram is like the "Figure 8" value, and the second is the metal part through which the current passes, which can effectively reduce the resistance selection. 1. The advantage of not being easy to oxidize is a good choice of contact layer. The above-mentioned ones are not used to limit the equal changes made by the hairpin, which are only the preferred embodiments of the present invention, and the scope of implementation is clear; Any patent application and modification according to the present invention shall be covered by the scope of the invention patent.

200411694 Brief Description of Drawings Figure 1 is a cross-sectional view of the structure of the first embodiment of the present invention after the completion of the complementary metal-oxide semiconductor process; Figure 2 is a structure of the first embodiment of the present invention after the wet chemical etching is completed Sectional view; FIG. 3 is a structural sectional view of the first embodiment of the present invention after electrodeless plating is completed; FIG. 4 is a structural perspective view of the first embodiment of the present invention; and FIG. 5 is a second embodiment of the present invention Cross-sectional view of the structure after the complementary metal-oxide semiconductor process is completed; FIG. 6 is a cross-sectional view of the structure of the second embodiment of the present invention after wet chemical etching is completed; FIG. 7 is a completed view of the second embodiment of the present invention A sectional view of the structure after electrodeless plating; and FIG. 8 is a perspective view of the structure of the second embodiment of the present invention. [Symbol description] 100 silicon wafer 101 first metal layer 102 first insulating layer 103 second metal layer 103a input terminal 103b output terminal 104 pin layer 105 third metal layer 105a contact surface

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Page 14

Claims (1)

A metal with an insulating layer is formed on the first layer above the first one, and the second layer is a mobile device that returns the structure and direction of the structure, and the electrical appliance that is a joint, and the scope of the patent application1. An electrostatic drive The micro-relay of work has a substrate, which is composed of a silicon wafer with a first layer, a silicon layer with a first insulation layer, a silicon layer with an insulation layer, and a silicon wafer with a second layer. The metal layer is located on the tool; " The first insulation layer is located on the first metal input terminal and-& two metal layers and a first-connected] and 'located on the substrate, is above the two metal layers, The wheel contact is composed of the first contact level as an external circuit input. The two ends and the output end are independent floating structures, respectively, the pipeline of the micro-relay; and a second contact layer, A 2 The third metal layer on the input end and the output end is located on the three metal layers composed of the tri-metal layer and a protective layer; the human-contact layer, and the input voltage i » A substrate and the suspension junction; the first metal layer and The third metal moves down to generate an electrostatic force with the wheel, attracting the suspension path, and by controlling the wheel 2 ^ the output terminal to form a conduction direction, the packed pressure switch can be controlled, and the suspension structure 2 .If applying for a patent; Γ: No .: continuity or not; pass. Among them, the micro-reduction of the electric drive described in the first metal item. -The material of the layer is selected from the Ming and Ming alloys. 3 · As in the patent application ... where the electrostatic drive of the micro-subsequent described in the first-pendi item 4 such as φ & Silicon oxide. The electrostatically driven micro-relay device described in Qianweidi 1 200411694 6. The scope of the patent application where the material of the second metal layer # S ^ ^^ is selected from the Ming and Su alloys ", & 诰 镕 镕 镕 心 $ 诞, 合 合", W Cheng, and the person applies The #B mentioned in item 丨 of the patent scope, wherein the -contact layer is made of -layer nickel and: J-driven micro-relay. 6. As described in the scope of patent application item # 1 = benefit. ′ The second contact layer is composed of a layer of nickel and a driven micro-relay circuit. . The material of the second metal layer is selected from the group consisting of I-driven micro-relay ... Aluminum and 1 Lu alloy group: No. 5 · The production method of an electrostatic-driven micro-relay, its steps Containing Tan / Yi Shi An "a) Provide a silicon crystal with an insulating layer (b) on the first metal layer of the Shi Xi wafer with the insulating layer as a control voltage of 9 rounds. Table J® deposition and definition An electrical pipe; 1 " Hydraulic drive micro-relay (c) forms a first insulating layer sloping on the concrete surface and defines its figure; and uses the table (d) of the first metal layer on the first The surface of the insulation layer defines its pattern to form a separate "shell-second metal layer", and the input end and the output end are used as the pipeline of the micro-relay driven by the external wheel input end and an output end; (A) Turn in and output the static electricity (e) on the surface of the second metal layer to form a sacrificial layer; M sub-defines a pin layer, (f) sinks on the surface of the plug lock layer ... a third metal layer Total product definition 200411694 VI. Patent application pin 1 as a control circuit guide A suspension structure and a control voltage are connected to the pipeline of the electrostatically driven micro-relay. The suspension structure includes a @ 4 plate and a cantilever beam. The shape of the contact plate covers the input terminal window. Bare: = the pin layer To be used as a wet connection. The cantilever beam and the second metal layer below protect the electrostatic layer, which protects the electrostatic layer. It is placed on the surface of the suspension structure to protect the wet structure. The device is free from oxidation and damage; and the floating structure is suspended in the pre-etching, and the sacrificial layer is removed, so that the suspension 9. As in the patent application range No. 8 = and above the output terminal. The manufacturing method, wherein the step (b) to step (g) of the metal-oxide semiconductor manufacturing process of the electrostatically driven micro-relay described in this step is to use the existing complementary manufacturing method as described in the patent scope, wherein One of the combinations of electrostatically driven micro-relay gold described in ##. The material of the metal layer is selected from the chain and the method of eleven. The manufacturing method of the scope of patent application, wherein the electrostatic relay-driven micro-relay described in the μ item 12. The scope of the patent application ~ The material of the insulation layer is dioxide. Shi Xi. The manufacturing method, wherein the electrostatically driven micro-relay gold described in item f 8 is one of the combinations. The material of the first metal layer is selected from the production method of aluminum and succinct 13. If you apply for a patent, you can use the electrostatically driven micro-relays described in this chapter. The material of the layer is an interlayer of tungsten and titanium. Page 17 The electrostatic relay-driven micro-relay device described in item 8 6. The method of making a patent application, which is one of the combinations of 385 gold. The material of the i-layer is selected from aluminum and Minghe 15. For example, the manufacturing method of the scope of patent application No. 8 ^, in which the micro-relay of electrostatic driving is used to make the third metal. Layer and the 2 ^ type chemical etching to remove the sacrificial layer, and the money engraving solution used is a step of hydrogen peroxide to form a suspension structure, which is a kind of electrostatic drive. # 有 ·· ^ Transporter The manufacturing method includes the steps of: (a) providing a Shi Xi wafer having an insulating layer α); a first metal layer, which is used as a batch to deposit and define a pipeline of an electrical appliance; The micro-reduction (c) of the electrostatic drive is formed into a first dimension and defines its figure; the layers of 、, and 彖 are coated on the table of the first metal layer (d) Defined on the _ absolute iron Graphic, a second metal layer is deposited on the surface of Xingwei, and the input terminal and the output terminal are -input terminal and -output terminal, and the micro-relay driven by the mode is used to input and output the static electricity to the external circuit (e) Deposit a sub-defined pin layer on the second + M to form a sacrificial layer; jf) a third metal layer is deposited on the surface of the pin layer and defines a pipeline of a floating structure and a micro-relay that controls the voltage of the circuit, and the suspension structure includes an anti-cantilever beam, and the contact The shape of the plate includes the end of the wheel Page 18 200411694 200411694 VI. Patented agricultural method 'where the thirst-type chemical treatment is to remove the sacrificial layer by etching, so that the second metal layer and the protective layer form a suspension junction. The etching solution used is hydrogen peroxide. Step V. 24. A method of manufacturing an electrostatically driven micro-relay, the steps include: (a) providing a silicon wafer with an insulating layer; (b) forming a silicon wafer with an insulating layer The surface deposits and defines a micro relay that is used as a control voltage to turn into the electrostatic drive. (c) forming a first insulating layer overlying the first gold surface and defining its pattern; θ and (d) depositing a second metal layer on the surface of the first insulating layer and defining its pattern to form An independent input terminal and an input terminal, the input terminal and the output terminal are used as external > circuit input and output pipelines of the micro relay driven by the type; ^ (e) deposited on the surface of the second metal layer And define a latch pin to form a sacrificial layer; (f) Deposit and define on the surface of the pin layer-a third metal layer and a pin as a suspension structure for conducting the control loop and controlling the voltage to be input to the pipe of the electrostatically driven micro-relay. The suspension structure includes ^ There is a contact plate and a cantilever beam. The shape of the contact plate includes the wheel input end and the output end, and a part of the pin layer is exposed to serve as a window for wet chemical etching afterwards. And the second metal reed is connected; 9 200411694 In order to protect (g), a protective layer is formed to cover the micro-relay device for protecting the electrostatic drive μ :: ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, g ,, h) Wet chemical etching is performed, and the floating structure is suspended on the input end and the output end: above, and, so that the suspension element (!) is electrolessly plated on the input end and H 'and the The surface of the third metal layer is electro-ore-layered with nickel: two: a layer of gold to form gold-to-gold contact, which can reduce the current loop value and is not easy to oxidize. The micro-relay that is also driven by the resistance uses the existing Complementarity 2 5 · The static electricity manufacturing method as described in item 24 of the scope of patent application, wherein steps (b) to (g) are performed using a gold semiconductor manufacturing process. The method for fabricating the electrostatically driven micro-relay described above, wherein the material of the first metal layer is one selected from the group consisting of aluminum and aluminum alloys. 272 The electrostatic type described in item 24 of the scope of patent application Method for cracking a driven micro-relay, wherein the first insulating layer The material is silicon dioxide. 28. The manufacturing method of the electrostatically driven micro-relay described in item 24 of the patent application scope, wherein the material of the second metal layer is one selected from the group consisting of aluminum and aluminum alloy. 29. The method for manufacturing an electrostatically driven micro-relay as described in item 24 of the scope of patent application, wherein the pin layer is made of an interlayer of tungsten and titanium. 30. The static electricity as described in item 24 of the scope of patent application A method for manufacturing a micro-relay driven by a battery, wherein the material of the third metal layer is one selected from the group consisting of aluminum and aluminum alloy. 200411694 31. The manufacturing method of static as described in claim 24 of the scope of the patent application, wherein the micro-relay with wet chemical etch is used to form the third metal layer and the protective layer into a county: the sacrificial layer, the used The etching solution is hydrogen peroxide. The steps of heart pre-structuring, 32. There are: The manufacturing method of an electrostatically driven micro-relay includes the steps of: a) providing an insulating layer ^ (b) depositing on the surface of the silicon wafer having the insulating layer Define the μ layer to control the electrostatic drive to input the electrostatic drive micro: The surface of a metal layer, (c) forming a first insulating layer covering the first surface and defining its pattern; ten wires (d) depositing a second metal layer on the surface of the first insulating layer, and 疋 = The figure is formed to form an independent input terminal and an output terminal, and the wheel input terminal and the output terminal are used as an external circuit input and output pipe of the electrostatically driven micro-relay; (e) in the second metal layer Deposit and define a pin layer on the surface to form a sacrificial layer; (f) deposit and define a third metal layer and pin on the surface of the pin layer as a suspension structure and control voltage input for control circuit conduction In the pipeline of the electrostatic-driven micro-relay, the suspension structure includes a contact plate and a cantilever beam. The shape of the contact plate includes the input end and the output end, and a part of the pin layer is exposed for wetness. Chemical etching window, and the cantilever beam and the second metal layer below Page 22 200411694 The six patent application scopes are connected; (㈧ A protective layer is formed to cover the suspension and the pins are exposed; 苒 之》 海 心 # 梁 D line wet chemical etching to remove the sacrificial layer Two metal layers are suspended on the input end and the wheel output end; and '-brother (= using electrodeless plating method to record on the input end end and the upper and lower surfaces of the third metal layer, and then power on Money-layer gold to form the gold-to-gold circuit resistance value and not easy to oxidize. Niu low electric catch I1 system: The electrostatically driven micro-relay described in Item 32 of the patent scope = method, where step (b) Step (g) is carried out by using an existing complementary pentoxide semiconductor process. ^ The method of manufacturing the electrostatically driven micro-relay white and clothing as described in item 32 of the patent application scope, wherein the material of the first metal layer It is selected from the group consisting of aluminum and aluminum alloy. 35 \ The manufacturing method of the electrostatically driven micro-relay described in item 32 of the patent application scope, wherein the material of the first insulating layer is silicon dioxide. 3 Item 6 of the 6 system as claimed The method of fabricating the electrostatically-actuated micro-relay described above, wherein the material of the second metal layer is selected from the group consisting of Shao and Ming alloy. The manufacturing method of the electrostatically driven micro-relay, wherein the material of the pin layer is an interlayer of tungsten and titanium. Page 23 18 8. The manufacturing method of the electrostatically driven micro-relay as described in item 32 of the patent scope of Shenyin, wherein the material of the third metal layer is selected from the group consisting of aluminum and aluminum alloy 200411694 6. Scope of patent application One of the combinations made by gold. 3 9. The manufacturing method of the electrostatically driven micro-relay according to item 32 of the scope of the patent application, wherein the wet chemical etching is performed, and the sacrificial layer is removed, so that the third metal layer and the protective layer form a For the suspension structure step, the etching solution used is hydrogen peroxide. Page 24