MEMS devices built on substrates using ruthenium-based interface materials

Abstract

A method for fabricating and packaging an ohmic microelectromechanical system (MEMS) switch device is provided. A method for fabricating and packaging an ohmic microelectromechanical system switch device includes constructing the switch device on an insulating substrate, where the switch device may have contacts made of a platinum group metal. The method may further include forming an oxide layer of the platinum group metal on the outer surface of each of the one or more contacts. The method may further include bonding an insulating cap to the insulating substrate to hermetically seal the switch device. The bonding may be performed in an atmosphere having an oxygen percentage in the range of 0.5% to 30%, whereby after the switch device is sealed in the hermetic cavity, the atmosphere in the hermetic cavity has an oxygen percentage in the range of 0.5% to 30%. The platinum group metal may be ruthenium, and the platinum group metal oxide layer may be ruthenium dioxide.

Description

Related Applications

[0001] This application is a continuation of U.S. Application No. 16 / 832,408, filed March 27, 2020. This is a continuation application of the above application, the entire teachings of which are incorporated herein by reference. [Background technology]

[0002] In devices such as microelectromechanical systems (MEMS) switches, Packaging is often required to protect the components from environmental contamination. The cage is typically formed using a discrete or wafer-bonding process. The reliability and stability of the switch may be impaired if exposed to uncontrolled operating environmental conditions. Moisture and contamination can cause poor initial performance and increased premature device failure. Therefore, such devices must, at least to some extent, separate their internal environment from the external It is common to store it in a protective package that isolates it from the environment. The process of encapsulating the device is designed to ensure a reliable, long-lasting sealed switch device. is very important to

[0003] RuO2 contacts (contacts) built on silicon substrates and enclosed in hermetically sealed packages Examples of prior art MEMS switches having a . . . ) are found in, for example, U.S. Pat. No. 7,968,364 No. 8,124,436, 9,583,294, 9,784,048, 10,38 No. 8,468, and U.S. Patent Application Publication No. 2007 / 0115082. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 7,968,364 [Patent Document 2] U.S. Patent No. 8,124,436 [Patent Document 3] U.S. Patent No. 9,583,294 [Patent Document 4] U.S. Patent No. 9,784,048 [Patent Document 5] U.S. Patent No. 10,388,468 [Patent Document 6] US Patent Application Publication No. 2007 / 0115082 Summary of the Invention [Problem to be solved by the invention]

[0005] Embodiments of the present invention provide a hermetically sealed junction wall containing a microelectromechanical system (MEMS) switch. The MEMS switches are directed to the wafer stack and are made of ruthenium oxide (e.g., RuO 2) contacts, which contain oxygen or oxygen, nitrogen, and / or noble gases; The mixture is enclosed in a sealed enclosure containing [Means for solving the problem]

[0006] Exemplary embodiments herein include stoichiometric rutile structure ruthenium dioxide (RuO 2) describes a MEMS switch device constructed on a substrate with the material of the contact surface. The MEMS switch device is a gas that reacts with a small amount of oxygen (O2) and other inert gases, such as argon. The joining process, e.g., thermal compression, is carried out in an atmosphere containing argon (Ar) and / or nitrogen (N). (TC) Hermetically sealed by wafer bonding process. Contact material is Ru or Ru-containing The top and exposed contact materials may be a stack of metals or Ru alloys. A preferred embodiment further comprises a pre-bonding oxygen plasma ash cleaning step for the glass substrates. The process flow is directed towards creating a RuO2 (conductive oxide) contact surface that can be The excited oxygen ions generated by the plasma are deposited on the R It reacts effectively with u atoms and forms a high-quality thin layer of RuO2 during plasma ash cleaning. The RuO2 contacts thus obtained enable the MEMS switch device to: Low contact resistance can be maintained through billions of switching cycles.

[0007] The exemplary embodiments further describe several device enhancement techniques. One technique is , regarding the inclusion of oxygen within a cavity to mitigate the buildup of organic contaminants on the contact surface. , which improves manufacturing yield and switch device lifetime. Another enhancement technique is the use of Ru O2 is an oxygen heat treatment before bonding to increase the thickness of the contacts, further increasing the life of the switch. To improve the efficiency, an inert gas may be added to the sealed environment.

[0008] In an exemplary embodiment, the MEMS switch device is mounted on a wafer-based substrate, e.g. Silicon, silicon dioxide (SiO2), fused silica, silica glass, quartz, sodium May be constructed on doped glass, borosilicate glass, sapphire, SOI, etc. RuO2 The contact surface material is a glass substrate and deposited Ru contact material prior to the thermocompression (TC) bonding process. It can be created by oxygen plasma ash. Typically, the expectation is to clean any organic residues on the substrate, including the contact surface. A clean, stoichiometrically oxidized contact surface leads to a low and stable contact resistance. Additional processing steps, such as a temperature increase step before bonding or oxygen introduction during the mechanical joining step, can enhance the Ru The O2 contact layer solidifies and thickens further.

[0009] In one aspect, the present invention provides a method for manufacturing an ohmic microelectromechanical system (MEMS) sensor on a substrate. Fabrication and testing of ohmic MEMS switch devices, including constructing a switch device The ohmic MEMS switch device may be a platinum group metal. The method further comprises the step of: and further comprising forming an oxide layer of a platinum group metal on an outer surface of each of the one or more contacts. The method may further comprise bonding a cap to the substrate in the second chamber, thereby An ohmic MEMS switch is placed in a sealed cavity formed by the cap and the substrate. The bonding may further include hermetically sealing the device. The bonding may be performed in an atmosphere with a percentage of oxygen within the atmosphere, which allows for ohmic bonding. After the MS switch device is sealed in the sealed cavity, the cavity in the sealed cavity The atmosphere will have an oxygen percentage in the range of 0.05% to 30%.

[0010] In one embodiment, the substrate and cap may each be composed of an insulating material. The platinum group metal may be ruthenium (Ru), and the oxide layer of the platinum group metal may be ruthenium dioxide. The ohmic MEMS switch device can be constructed using a material other than ruthenium (RuO2). fabricated ohmic MEMS switch devices on a substrate using a thin-film microfabrication process. The method may further include providing a platinum group metal on an outer surface of each of the one or more contacts. Forming an oxide layer is achieved by oxygen plasma ashing on ohmic MEMS switch devices. The method may include performing the steps of: applying a platinum group metal to an outer surface of the one or more contacts. After forming the metal oxide layer, the platinum group metal oxide layer on the outer surface of one or more contacts is strengthened. To achieve this, an oxygen plasma ash cleaning procedure was performed on the ohmic MEMS switch device. The method may further include performing

[0011] The bonding atmosphere may have an oxygen percentage in the range of 0.05% to 30%. Bonding the chip to the substrate involves a profile that characterizes the bonding temperature and bonding force over time. Therefore, by exposing the cap and the substrate to the bonding temperature and pressing the cap and the substrate with a bonding force, The method may further include:

[0012] The substrate may be one of a plurality of substrates on a first wafer, and the cap may be one of a plurality of substrates on a second wafer. The cap may be one of multiple caps on the wafer. means bonding a first wafer according to a profile that characterizes bonding temperature and bonding force versus time; and exposing the first wafer and the second wafer to a bonding temperature, and bonding the first wafer and the second wafer together to a bonding force. The joining atmosphere may further include (i) nitrogen (N2) and and (ii) an inert noble gas, or both.

[0013] In another aspect, the present invention provides an ohmic microelectromechanical system (ME) constructed on a substrate. The switch device may be an Ohmic MEMS (Ohmic Micro-Electro-Mechanical Systems) switch device. The switch device may have one or more contacts made from a platinum group metal. The switch device is configured to remove platinum group metal oxide formed on the outer surface of each of the one or more contacts. a cap disposed on the substrate and bonded to the substrate; A hermetically sealed cavity may be formed surrounding the switch device. The cavity atmosphere in the cavity has an oxygen ratio in the range of 0.05% to 30%. Good too.

[0014] The substrate and the cap may each comprise an insulating material. The platinum group metal may be ruthenium ( The platinum group metal oxide layer may be ruthenium dioxide (RuO2). Ohmic MEMS switch devices can be fabricated on substrates using thin-film microfabrication processes. The platinum group metal oxide layer on the outer surface of each of the one or more contacts may be formed. may be formed using an oxygen plasma ash procedure on the MEMS switch device. The platinum group metal oxide layer forms on the outer surface of one or more contacts. After that, an oxygen plasma ash cleaning procedure was used on the ohmic MEMS switch device. may be strengthened.

[0015] The cavity atmosphere in the sealed cavity is in the range of 0.05% to 30% oxygen. The bonding temperature and the bonding pressure may be varied over time to bond the cap to the substrate. The cap and substrate are subjected to a bonding temperature according to a profile that characterizes the bond time. The cap and the substrate may be pressed together with a bonding pressure. The insulating substrate is placed on the first insulating wafer. The insulating cap may be one of a plurality of insulating substrates provided, and the insulating cap may be a second insulating substrate. It may be one of a plurality of insulating caps provided on the wafer.

[0016] To bond the insulating cap to the insulating substrate, the bonding temperature and bonding pressure are characterized with respect to time. The first insulating wafer and the second insulating wafer are subjected to a bonding temperature according to a bonding profile. Alternatively, the first insulating wafer and the second insulating wafer may be pressed together with a bonding pressure. The atmosphere may further comprise one of: (i) nitrogen (N2) and (ii) an inert noble gas. Or it may include both.

[0017] In another aspect, the present invention provides an ohmic contact on a fused silica substrate using a thin film microfabrication process. Ohmic Microelectromechanical Systems (OHM) technology, including building MEMS switch devices. The present invention may be a method for manufacturing and packaging an ohmic (MEMS) switching device. The MEMS switch device has one or more contacts made of ruthenium (Ru). The method may further comprise: disposing, in the first chamber, a first electrode of each of the one or more contacts; forming a layer of ruthenium dioxide (RuO2) on the outer surface; and in a second chamber: A fused silica cap is bonded to a fused silica substrate, thereby forming a fused silica cap and a fused silica substrate. and hermetically sealing the ohmic MEMS switch device within a sealed cavity formed therein. The bond may further comprise a bond having an oxygen percentage in the range of 0.05% to 30%. This may be done in an ambient atmosphere, which results in a hermetic ohmic MEMS switch device. After sealing in the cavity, the cavity atmosphere in the sealed cavity should be 0.05% to 3 This method involves the external application of oxygen to one or more contacts. To enhance the RuO2 on the outer surface of one or more contacts after forming RuO2 on the surface. Additionally, the ohmic MEMS switch device was subjected to an oxygen plasma ash procedure. may be included in.

[0018] The patent or application file contains at least one drawing in color. Copies of color drawing(s) of any patent application publication will be provided by the Office upon request and payment of the necessary fee. It is served.

[0019] The above is an exemplary embodiment of a method for manufacturing a vehicle, as shown in the accompanying drawings, in which like reference characters refer to like parts throughout the different views. This will become apparent from the more detailed description of the preferred embodiments. The emphasis is instead on illustrating embodiments. [Brief explanation of the drawings]

[0020] [Figure 1A] 1 is a detailed cross-sectional view of an example of an embodiment of a switch device according to the present invention; [Figure 1B] 1B is an exploded view of a substrate portion of the switch device shown in FIG. 1A. [Figure 1C] 1B is an exploded view of a cap portion of the switch device shown in FIG. 1A. [Figure 1D] 1B is an enlarged view of the contact area of ​​the switch device shown in FIG. 1A. [Figure 2] FIG. 10 is a diagram showing an example of a process flow for preparing and bonding a glass substrate wafer equipped with a MEMS switch and a glass cap wafer. [Figure 3] 1A-1C illustrate exemplary embodiments of thermocompression (TC) bond profiles according to the present invention. [Figure 4A] FIG. 10 illustrates an exemplary embodiment of flowing an oxygen-containing gas through a bonding chamber according to the present invention. [Figure 4B] FIG. 10 illustrates an exemplary embodiment of flowing a nitrogen-containing gas through a bonding chamber according to the present invention. [Figure 4C]FIG. 10 illustrates an exemplary embodiment of flowing a gas containing an inert noble gas through a bonding chamber according to the present invention. [Figure 5A] 1A-1C illustrate exemplary embodiments addressing pre-treatment steps for forming a RuO2 contact layer in accordance with the present invention. [Figure 5B] 1A-1C illustrate exemplary embodiments addressing pre-treatment steps for forming a RuO2 contact layer in accordance with the present invention. [Figure 5C] 1A-1C illustrate exemplary embodiments addressing pre-treatment steps for forming a RuO2 contact layer in accordance with the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] An embodiment example will be described below.

[0022] The teachings of all patents, published applications and references cited herein are hereby incorporated by reference. The whole thing is incorporated.

[0023] Ruthenium (Ru) as a contact material is used in conjunction with ruthenium dioxide (Ru) as a contact surface material. O2) has been used in various mechanical relays and reed switch products since the 1960s. RuO2 contacts have low and stable contact resistance, as well as extremely high hardness and good corrosion resistance. exhibit desirable mechanical properties such as high temperature resistance and wear resistance. In the case of switching contacts (opening and closing while current is being transmitted), RuO2 is a high-strength alloy. It exhibits the ability to withstand arc discharges and is resistant to sticking and pitting. Although the exemplary embodiments herein describe Ru contacts with RuO2 contact surface material, Other embodiments include any platinum group metal (e.g., Ru, Rh, Pd, Os, Ir, or P t), and a contact consisting of a corresponding oxide layer of a platinum group metal may be utilized.

[0024] Ru forms a native, self-limiting oxide surface layer when exposed to an O2-containing environment. If the oxidation temperature is above a certain threshold (over 200°C in most literature), other types Stoichiometric ruthenium dioxide is used, rather than conventional Ru oxides (e.g., RuO, RuO3, and RuO4). A stoichiometric RuO2 layer is formed. RuO2 is a conductive oxide material with a resistivity of Approximately 3.5~4.6×10 -5 Ω·cm. This value corresponds to the specific resistivity of Ru, 6.71 to 7. 16×10 -6 Ω cm, but much lower than other forms of Ru oxide. In a warm gas environment, the surface oxidation process of Ru is self-limiting up to 10 Å. RuO2 has a dense lattice structure, which restricts the penetration of O2 to form more RuO2 underneath. As a result, other types of Ru oxides are formed. The contact resistance is 5 to 10 times higher than that of stoichiometric RuO2, and this resistance is It has been found that the contact resistance increases with time, but stoichiometric RuO2 exhibits a stable low contact resistance. .

[0025] Other methods for forming RuO2 include oxygen plasma treatment and the formation of RuO2 in an Ar / O2 mixed environment. Direct sputtering of uO2 onto the surface, chemical vapor deposition (CVD), and atomic layer deposition (ALD) The sputtering method can obtain a thicker oxide film than other methods. Therefore, Ru is used as the contact material instead of highly conductive metals such as gold, silver, copper, and aluminum. EMS switches can be manufactured.

[0026] MEMS switches have historically been derived from silicon CMOS process technology and are generally They are built on semiconductor substrates (e.g., silicon), which makes them ideal for the manufacturing infrastructure of MEMS devices. Most of the MEMs are based on the assumption that they will use silicon substrates. Commercialization of S-switch technology is expected / projected to be primarily implemented on silicon-based substrates Only for special applications (such as microwave technology) are MEMS switch devices made of non-silicon It is manufactured on a substrate.

[0027] The contacts of a gold (Au) MEMS switch are coated with a hard material such as Ru to However, the hard material itself used for the contacts can However, it is not possible to prevent premature failure of the switch during cycling (typically within a few hundred million cycles). The failure mechanisms are wear, micro-welding, surface roughness due to spalling, organic Possible causes include the accumulation of polymer contaminants on the surface. Oxidation of the Ru contact surface or the contact material Direct deposition of RuO2 as a contact surface significantly improves the thermomechanical performance of MEMS switches. MEMS switch devices generally have a long lifespan. Packaged in a hermetically sealed clean environment to ensure lifetime device performance This is because the switch contacts are not exposed to moisture or contamination, unlike traditional mechanical switches or relays. This is an approach that is widely adopted in the

[0028] The exemplary embodiments described herein are based on insulating substrates, e.g., silicon dioxide, fused silica, Constructed on silicon, silica glass, quartz, sodium-doped glass, and borosilicate glass Although we present a MEMS ohmic contact switch that can be fabricated using other non-insulating substrate materials (e.g., silicon), In an exemplary embodiment, fused silica is used to reduce electrical loss. It may be chosen as the base substrate material due to its extremely low loss characteristics. Excellent low insertion loss and high power DC and / or R for RF and microwave applications Switching devices with excellent isolation for use as RF or microwave switches. In an exemplary embodiment, RuO2 is used for the upper and lower MEMS switch contact surfaces. This extends the switch life beyond billions of cycles. FIG. 1A shows an example of an embodiment of a switch device 100 according to the present invention. 1B, 1C, and 1D are detailed cross-sectional views of the switch device depicted in FIG. 1 shows a detailed view of a particular part of the

[0029] Referring to FIG. 1A, an exemplary switch device 100 includes a substrate 102 shown in isolation in FIG. 1B. 1C. The 00 contact area 102 is shown in isolation and enlarged in FIG. 1D.

[0030] Referring to the exemplary embodiment depicted in FIG. 1B, the substrate portion 10 of the switch device 100 4 may include a substrate (e.g., fused silica) 108. A layer of electrically insulating material 110 , may be deposited on one or both of the upper and lower surfaces of the insulator substrate 108. Both the first and second bonding sites 112 and 114 connect the switch device substrate 104 to its corresponding carrier. Various metals, including bonding metals used to mechanically and electrically connect to the chip 106. and metal stacks used for either metal compression or metal eutectic bonding approaches. (The metal stack can be for metal compression bonding or metal eutectic bonding. The bonding metallurgy of the first and second bonding sites 112, 114 is formed by the insulating material layer. The first and second bonding sites may be formed on an adhesion layer 116 deposited on the first and second bonding sites. 114, 116 are gold-plated metals that are bonded to corresponding gold on the cap portion 106 during the bonding procedure described herein. Such junctions may be connected to switch elements (e.g., The switch device 100 is arranged around the beam, gate, and switching contacts described below. a cavity 111a (see FIG. 1A) that separates the switch element from the external environment 111b. The environment within cavity 111a is the same as the environment 11 surrounding the bonded switch device. The pressure and gas composition may differ from 1b.

[0031] A first end of the beam 118 is in electrical communication with the bond site 112 and the substrate 108. The first contact arrangement 126 may be fixed to the conductive traces to which it is mechanically coupled. The first contact arrangement 126 may be disposed at a second end of the beam 118. a Ru layer 130 mechanically coupled to the underside and electrically communicating with the beam 118; The second corresponding contact arrangement 134 may include a RuO layer 132 formed on the outer surface of the , a conductive material electrically connected to the bonding site (114) and mechanically bonded to the substrate 108. A Ru layer 136 is deposited on the extension of the conductive trace, and a Ru layer 136 is formed on the outer surface of the Ru layer 136. The second contact 134 may be formed by connecting the beam to a gate electrode 140. When actuated by the puller and pulled toward the substrate, the first and second contact surfaces come into contact and electrically The first contact 126 is positioned below the beam with similar X and Y coordinates to communicate effectively with the first contact 126. In the exemplary embodiment, the Ru layer 136 is the second junction site 11. In other embodiments, the Ru layer is deposited on a portion other than the junction site. For example, in some embodiments, additional electrical circuit elements may be provided in the third contact arrangement 1. 34 and the bonding site 114.

[0032] The gate structure 140 consists of a conductive metal layer 142 deposited on an insulator substrate 108. The gate structure 140 is used to generate an electromotive force on the beam 118. 126, so that the RuO2 layer 132 of the first contact arrangement 126 is The beam can be deflected until it makes electrical contact with the RuO2 layer 138 at 4.

[0033] Referring to FIG. 1C, the cap portion 106 of the switch device 100 is made of an insulating material such as fused silica. The insulating cap 150 may include an insulating cap of edging material, which may be any suitable insulating cap suitable for use in the art. The insulator cap 150 may be constructed of any other such insulating material known in the art. The adhesive layer 156 is formed on a metal layer 156 such as tantalum (Ta). a third bond site 152 and a fourth bond site 154 made of a bonding material such as in a position to provide junction with the first binding site 112 and the second binding site 114 At least one electrically conductive sealed through glass via (TGV) 15 may be formed. 8 may be disposed within the insulator cap 150, thereby allowing the cap portion 106 to The switch device 100 is sealed within a cavity formed after being bonded to the plate portion 104. This makes it easier to conduct electrical signals between the components.

[0034] An oxygen-based process is used to oxidize the Ru contact surface in a wafer bonding system. In contrast to the approach of directly sputtering RuO2 material, In an embodiment, prior to thermocompression (TC) bonding, an oxygen plasma ash process is performed for two purposes. The primary purpose of the oxygen plasma ash process is to remove organic matter on the contact surface. The second purpose of the oxygen plasma ash process is to remove the Ru contacts. The subsequent bonding process involves passivating the surface and forming RuO2. 0% oxygen, but in the illustrated embodiment, the oxygen percentage is 20 In other embodiments, the bonding environment may contain oxygen, e.g., nitrogen (N2), , and / or one or more other gases, such as an inert noble gas, such as argon (Ar). It can be supplemented with gas.

[0035] The RuO2 layer is formed during the oxygen plasma ash process and is then capped in the bonding chamber. This is done before bonding the cap to the substrate, so there is no sealed device between the cap and the substrate. The oxygen introduced into the device environment is substantially eliminated by Ru-catalyzed oxidation during the bonding process. As a result, the oxygen percentage of the gas enclosed in the device environment is The oxygen ratio may be equal to or close to the oxygen ratio of the gas stream supplied to the In this case, the oxygen percentage in the sealed device environment may be 20%, but in other environments It may also indicate an oxygen percentage between 0.05% and 30%.

[0036] Figure 2. Prepare a substrate wafer that can be equipped with one or more MEMS switches. 2 illustrates an exemplary embodiment of a process flow 200 for bonding a semiconductor wafer to a cap wafer. This exemplary embodiment is directed to the use of a glass substrate wafer and a glass cap wafer. However, other embodiments may utilize other insulating or non-insulating wafers. Any suitable mating surface to facilitate bonding to a substrate portion in the bonding process. It should be understood that a cap may be used.

[0037] The process flow 200 involves fabricating a device (e.g., a 202, forming a MEMS switch (e.g., a MEMS switch), and releasing the MEMS switch structure 204 (i.e., That is, the sacrificial support structure is eliminated, allowing the switch components intended to be movable to move freely. (thus exposing the Ru contact surface), followed by an oxygen plasma ash cleaning procedure. This may include performing 206 the test for at least 1 minute (4 minutes ± 0.1 minutes in the exemplary embodiment). stomach.

[0038] The MEMS wafer is then bonded to a corresponding cap wafer to encapsulate the device. This allows the device to be hermetically sealed in an oxygen-containing environment. It is fabricated by common microfabrication processes and may include electrical functional layers or mechanical layers. The cap wafer is made of a material that facilitates bonding to the corresponding MEMS device wafer. The device contains a material and functionality that allows the device to be hermetically sealed.

[0039] The substrate portion 104 and cap portion 106 are aligned and bonded together using a thermocompression (TC) bonding chamber. The substrate portion 104 and the cap portion 106 are loaded 208 into the bonding chamber. Once loaded, gas of the desired composition is flowed into the bonding chamber to the desired pressure 210. The chamber temperature is increased and the substrate and cap wafer are bonded 212 at a specific temperature and force. The process 200 continues by: Continuing in this manner, the exemplary bonding process is completed.

[0040] In one embodiment, a gas 210 is flowed into the bonding chamber to a desired pressure (as used herein). (described in more detail below) and applying a first bonding force (typically 20 seconds after the second bonding force). % or less) wafers are brought into contact (with each other), the temperature of the bonding chamber is increased, and a second, more A high force (bonding force) is applied, thereby bonding 21 the cap portion 106 to the substrate portion 104. The bonding chamber is maintained at the desired pressure with the gas, and the bonding force is The first bonding force (or a similar lower force) is reduced and the temperature within the bonding chamber is reduced.

[0041] In process flow 200, before the MEMS wafer is loaded into the thermal compression bonding apparatus, , during the oxygen plasma ash process step 206, a conductive oxide contact surface (e.g., R An exemplary TC profile according to the present invention is shown in FIG. The chamber temperature 302 (unit: °C) is related to the applied joining force 304 (unit: kN). The temperatures and pressures depicted in Figure 3 are examples provided for illustrative purposes only. It should be understood that the above is not intended to be limiting. Generally, the bonding temperature and pressure process The profile is used to achieve a bond between the substrate and the cap as described herein. The normal bonding process does not involve oxidation of Ru. No special bonding treatment is required to deal with oxidation of the Ru contact surface. The gas used to fill the chamber is either a N2 / O2 mixture or clean dry air (C DA), or inert gas / O2 mixture, or just inert gas, or one or may be any of the gases mentioned herein mixed with a plurality of inert noble gases.

[0042] During oxygen plasma ash treatment, stoichiometric rutile oxide, RuO2, is formed on the outer surface of the Ru contacts. Highly reactive O2 atoms penetrate the surface of bulk Ru but remain indefinitely below the surface. The ratio RuOX can be formed (where X is a positive real number). Such RuOX is converted to RuO2 by O2 plasma assimilation. After the wafer bonding step, an optional additional step can be performed to select a surface contact material. These options can be used to obtain thicker layers and higher percentages of RuO2. For example, as shown in Figures 5A, 5B, and 5C.

[0043] FIG. 4A shows the substrate and cap portions bonded together after an oxygen plasma ash step is performed. Once the chamber is loaded, oxygen (O2) containing gas is flowed into the bonding chamber. 4B shows an exemplary embodiment including a 2. Oxygen plasma ash step is performed. Once the substrate and cap part are loaded into the bonding chamber, nitrogen (N2 4C shows an exemplary embodiment including flowing 404 a gas containing An oxygen plasma ash step is performed and the substrate and cap parts are bonded in the bonding chamber. Once the bonding chamber is loaded, a gas containing an inert noble gas is flowed into the bonding chamber 406. In other embodiments, the inert gas is O2, N2, or both. In all three embodiments (FIGS. 4A, 4B, and 4C), The final step shown is to bond the substrate portion and the cap portion together as the bond is formed. With respect to continuing the gas flow as described in steps 402, 404, and 406, respectively. It is involved.

[0044] 5A, 5B, and 5C show the RuO2 contact layer described herein prior to the bonding process. 1 shows an exemplary embodiment dealing with pre-treatment steps for forming a RuO2 layer. Instead of forming a RuO2 layer between the Zuma Ash, a separate chamber is used for bonding. The RuO2 layer is formed in the oxygen plasma ash. All three embodiments (FIGS. 5A, 5B, and 5C) may be implemented using MEMS devices. After the device is loaded into the oven, the oven is filled with an oxygen-containing gas 502 and the device is heated for 20 Annealing above 0°C for at least 10 minutes is shown in Figures 5A, 5B, and 5C. C is a bonding chamber containing oxygen 504, nitrogen 506, or a noble gas 508, respectively. It shows how it flows.

[0045] Although exemplary embodiments have been particularly shown and described, it is understood that the scope of the appended claims encompasses all such modifications. Various changes in form and detail may be made therein without departing from the scope of the embodiments described. It will be understood by those skilled in the art that this can be done.

Claims

1. Fabricating and packaging ohmic microelectromechanical systems (MEMS) switch devices 1. A method of detecting a blood sample comprising: A process for constructing the ohmic MEMS switch device on a substrate, The electromechanical MEMS switch device has one or more contacts made of a platinum group metal. The process of creating and constructing In a first chamber, applying the platinum group metal to an outer surface of each of the one or more contacts. forming an oxide layer on the metal; bonding a cap to the substrate in a second chamber, The ohmic MEMS switch device is formed by the cap and the substrate. The bond is hermetically sealed in a sealed cavity formed therein, and the bond has a ratio within the range of 0.05% to 30%. The bonding is performed in a bonding atmosphere having a high oxygen concentration, thereby After the chip device is hermetically sealed in the sealed cavity, a bonding process in which the cavity atmosphere has an oxygen ratio in the range of 0.05% to 30%; and a method for providing the same.

2. 10. The method of claim 1, wherein the substrate and the cap each comprise an insulating material. Hmm, a method.

3. 2. The method of claim 1, wherein the platinum group metal is ruthenium (Ru), and the platinum The oxide layer of the metal group metal is ruthenium dioxide (RuO ２ ) a method.

4. 10. The method of claim 1, wherein the ohmic MEMS switch device is constructed forming the ohmic MEMS switch device on the substrate using a thin film microfabrication process; The method further comprising forming a vise.

5. 10. The method of claim 1, wherein the outer surface of each of the one or more contacts The step of forming the oxide layer of the platinum group metal is performing an oxygen plasma ash procedure on the silicon dioxide.

6. 2. The method of claim 1, wherein the platinum group metal is applied to an outer surface of the one or more contacts. After the step of forming the oxide layer, the ohmic MEMS switch device performing an oxygen plasma ash cleaning procedure to clean the outer surface of the one or more contacts; The method further comprising strengthening the oxide layer of the platinum group metal.

7. 2. The method of claim 1, wherein the joining atmosphere has a ratio in the range of 0.05% to 30%.

10. The method of claim 1, wherein the oxygen concentration is 0.1%.

8. 10. The method of claim 1, wherein the step of bonding the cap to the substrate further comprises: The cap and the bonding force are bonded according to a profile that characterizes the bonding temperature and bonding force with respect to time. and exposing the substrate to the bonding temperature; and bonding the cap and the substrate together to the bonding temperature. and pressing with a bonding force.

9. 10. The method of claim 1, wherein the substrate is one of a plurality of substrates on a first wafer. and the cap is one of a plurality of caps on a second wafer, and the cap The process of bonding the chip to the substrate further comprises characterizing the bonding temperature and bonding force with respect to time. and exposing the first and second wafers to the bonding temperature according to a profile set forth in the and pressing the first wafer and the second wafer together with the bonding force. Law.

10. 10. The method of claim 1, wherein the joining atmosphere comprises: (i) nitrogen (N ２ ) and (ii) ) an inert noble gas or gases.

11. Ohmic microelectromechanical system (MEMS) switch devices built on a substrate an ohmic MEMS switch having one or more contacts made of a platinum group metal; a device; an oxide layer of said platinum group metal formed on an outer surface of each of said one or more contacts; 、 The ohmic MEMS switch device is disposed on and bonded to the substrate. a cap forming a sealed cavity surrounding the seat, The cavity atmosphere in the sealed cavity has an acid content in the range of 0.05% to 30%. A switching device having a switching element.

12. 12. The switching device of claim 11, wherein each of the substrate and the cap 1. A switching device comprising an insulating material.

13. 12. The switching device of claim 11, wherein the platinum group metal is ruthenium (Ru). and the oxide layer of the platinum group metal is ruthenium dioxide (RuO ２ ), the switch ing device.

14. 12. The switching device of claim 11, wherein the ohmic MEMS switch device The switching device is formed on the substrate using a thin film microfabrication process.

15. 12. The switching device of claim 11, wherein each of the one or more contacts The oxide layer of the platinum group metal on the outer surface of the ohmic MEMS switch device A switching device formed using an oxygen plasma ash procedure on the seat.

16. 12. The switching device of claim 11, wherein the oxide layer of the platinum group metal is After the oxide layer of the platinum group metal is formed on the outer surface of one or more contacts, Enhancement using an oxygen plasma ash cleaning procedure on the ohmic MEMS switch device A switching device.

17. 12. The switching device of claim 11, wherein the cavity in the sealed cavity The atmosphere has a percentage of oxygen in the range of 0.05% to 30%.

18. 12. The switching device of claim 11, wherein the cap is bonded to the substrate. To do this, the bonding temperature and pressure are measured according to a profile that characterizes the bonding temperature and bonding pressure versus time. The cap and the substrate are subjected to the bonding temperature, and the cap and the substrate are bonded together. A switching device that presses with the above joining pressure.

19. 12. The switching device of claim 11, the insulating substrate is one of a plurality of insulating substrates on a first insulating wafer; The insulating cap is one of a plurality of insulating caps on a second insulating wafer. 、 In order to bond the insulating cap to the insulating substrate, the bonding temperature and the bonding pressure are varied in relation to time. the first insulating wafer and the second insulating wafer according to a profile characterizing the The first insulating wafer and the second insulating wafer are exposed to the bonding temperature and bonded together. A switching device that is pressed by combined pressure.

20. 12. The switching device according to claim 11, wherein the cavity atmosphere further comprises: i) Nitrogen (N ２ ) and (ii) an inert noble gas, ing device.

21. Fabricating and packaging ohmic microelectromechanical systems (MEMS) switch devices 1. A method of detecting a blood sample comprising: The ohmic MEMS switch was fabricated on a fused silica substrate using a thin film microfabrication process. a process for constructing a switch device, the ohmic MEMS switch device being constructing a semiconductor substrate having one or more contacts comprised of Ru; In a first chamber, a ruthenium dioxide (R ) is applied to the outer surface of the one or more contacts. uO ２ forming a ) layer; bonding a fused silica cap to the fused silica substrate in a second chamber; whereby, within the sealed cavity formed by the cap and the substrate, and hermetically sealing the ohmic MEMS switch device at a temperature of 0.5° C. The bonding atmosphere is in the range of 0.05% to 30%, and the ohmic MEMS switch After the chip device is sealed in the sealed cavity, the chip device is sealed in the sealed cavity. a bonding process in which the bonding atmosphere has a proportion of oxygen in the range of 0.05% to 30%; A method comprising:

22. 22. The method of claim 21, wherein the outer surface of the one or more contacts is ２ and subjecting the ohmic MEMS switch device to an oxygen plasma ash procedure after forming the to remove RuO from the outer surface of the one or more contacts. ２ Further strengthening the process Including, a method.

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