TW560028B - MEMS device sealing packaging method and the fabrication method of metal cap thereof - Google Patents

Abstract

A MEMS (micro electro-mechanical system) device sealing packaging method and the fabrication method of metal cap thereof are disclosed, wherein the sealing packaging is proceeded by using LIGA processing technology associated with IC packaging technology. Its method is to provide the first substrate, and a recess part is formed on the first substrate. Deposit a seed layer on the first substrate, and also fabricate the passivation layer on the seed layer, so as to fabricate a metal cap layer on the passivation layer as the metal cap, and cover/connect the metal cap on the second substrate having the MEMS device, remove the first substrate to seal and package the MEMS device.

Description

V. Description of the invention (υ [Field of invention] Method for mounting and its metal capping and manufacturing of blunt encapsulation micro-electro-mechanical components on a substrate The present invention is a method for sealing and sealing micro-electro-mechanical components, especially using a substrate to plate metal caps 'Layered layer' is good for the metal cover to be separated from the substrate, and the process is easier. [Previous Technology] The so-called micro electromechanical system (Micro Electromechanical Γ product: rMSJ is a sensor, microstructure, circuit, etc. = As the micro-electro-mechanical element (job S) is based on semiconductor technology, it has the advantages of compactness, high reliability, and difficult movements. It also integrates mechanical, electronic, material, optical and other processing technologies. MEMS 2 The main difference between integrated circuit chips is that micro-electro-mechanical components are generally moving parts and are relatively fragile. They are not conducive to transportation before packaging. Therefore, the manufacturing of micro-electro-mechanical components and packaging must be considered together, forming an important research area. / Please refer to the first and second figures, a curtain layer 11 a is formed on the first silicon substrate 10 a, and an opening 1 is defined on the curtain layer 丨 a by using an etching technique 1 2a, and through the opening 丨 2a, a recess 13a is engraved on the first silicon substrate 10a by wet etching, so as to use the recess 1a to accommodate the micro-electromechanical element 20a (MEMS). Referring to the second and fourth figures, a micro-electromechanical element 20a (MEMS) is disposed on an upper end surface of the second silicon substrate 30 and a lower end surface of the second silicon substrate 30a is provided. There is an electrical connection point 31a connected to the micro-electromechanical element 20a (MEMS), and a metal thin film 32a is plated on the second silicon substrate 30a. The 560028 V. Description of the invention (2)-Metal thin film 32a is disposed around the micro-electromechanical device 20a, and bumps 33a are plated on the metal thin film 32a. 々 Please refer to the fifth figure, and finally the first silicon substrate 10a and the first silicon The crystal substrate 30a is aligned so that the first silicon crystal substrate 10a and the bump 33a are tightly connected, so that the concave portion 13a of the first silicon crystal substrate 10a is covered on the micro-electromechanical element 20a for packaging. The micro-electro-mechanical component 20a. However, the conventional method for sealing and packaging a micro-electro-mechanical component still has disadvantages: 1. The conventional method for sealing and packaging a micro-electro-mechanical component, Although the first silicon substrate 10a can seal the microelectromechanical components of the second silicon substrate 30a, the electromagnetic wave shielding property of the first silicon substrate 10a is not good, so that the microelectromechanical The component 20a is susceptible to interference. 2. The conventional microcomputer t-component hermetic packaging method, the bottom surface 5 of the second crystal substrate 30a and the electrical connection point 31a are placed, and the electrical characteristics of the microelectromechanical component & Inconvenient to measure. 3 The conventional method for sealing and sealing MEMS components,… as a U-shaped body, its volume is relatively large. ^ The first ~ substrate edge is that the inventor has been working on products based on these shortcomings and on the basis of years In order to provide a reasonable design and effective improvement, the purpose of the invention is to provide a method for sealing and sealing micro-electromechanical components and / or metal seals. Cap A, which uses the first substrate to make a metal cap

Page 5 560028 V. Description of the invention (3)

In addition, the metal cover has better electromagnetic wave shielding properties. The two purposes of the present invention are to provide a micro-electromechanical element sealing method, a method and a metal cap manufacturing method thereof. The first cap and a square π-meter substrate are used to manufacture a metal cap instead of the first stone crystal substrate to reduce the occupied volume. . The purpose of the present invention is to provide a method for sealing and packaging a micro-electromechanical element and a metal sealing method thereof, which is easy to be fabricated on the second substrate, and is convenient for the measurement of the micro-electromechanical element, thus saving the manufacturing process and measurement. =

The fourth purpose of the present invention is to provide-a method for sealing and sealing a micro-electromechanical element and a method for manufacturing a metal cap thereof-and to make a passivation layer on a substrate. When a metal cap is fabricated on the passivation layer, the The metal cover is easily detached from the first substrate after being connected to the second substrate. 5. The fifth object of the present invention is to provide a method for sealing and sealing a micro-electromechanical element and a method for manufacturing a metal cap, wherein the first substrate can be reused to make a # metal cap, and it is not required to be on the first substrate. Re-making the seed layer and the sword layer makes the sealing and packaging process of the micro-electromechanical device shorter and reduces the process time, thus reducing the cost.

Sixth purpose of the present invention is to provide a method for sealing and encapsulating a micro-electromechanical element ^ its metal cap manufacturing method, in which a wafer can be used instead of a substrate, and a wafer-level micro-electromechanical element can be sealed and sealed. [Features of the Invention] According to the foregoing object of the present invention, a method for sealing and packaging a micro-electromechanical element and a method for manufacturing the metal cap of the present invention includes the steps of providing a first substrate with a recess formed thereon, and further forming a surface on the first substrate. Make a seed layer on, and

560028 V. Description of the invention (4) A passivation layer is additionally formed on the seed layer, and a metal cap layer is deposited on the passivation layer as a metal cap for the method of sealing and encapsulating the microelectromechanical element, and a first substrate is provided thereon. A micro-electromechanical element, a multilayer metal film (UBM) is deposited around the micro-electromechanical element of the second substrate, and bumps are formed on the multilayer metal film, and the first substrate and the second substrate are aligned so that the metal The perimeter of the seal is connected to the bump, and finally the first substrate is removed. ☆ In order to allow your examiner to better understand the features and technology of the present invention, please refer to the following detailed description of the present invention and the accompanying drawings. However, the attached drawings are not only for reference and explanation, but are not intended to limit the present invention. [Preferred Embodiment] As shown in FIG. 6, the present invention uses a microlithography electroforming mold manufacturing (A- ^ E) process. Technology and integrated circuit packaging technology to carry out a microcomputer sealed packaging method to use the first substrate 10 to make a metal cover 30 :: The metal cover 30 is placed on the second substrate 40 and tightly bonded to each other The sealing member may be a micro-electromechanical element 5◦ 40 on the first substrate to form a MEMS device package. For sealing, please refer to the sixth to tenth figures. The metal cover 30 of the packaging method is a substrate 10, which can be a stone wafer, and a long oxide stone layer or a nitride stone layer can be used as the layer 11 A first photoresist layer 12 is coated thereon, and a first opening 13 is formed on the resist layer 12 to indicate that the micro-electromechanical element of the present invention is fabricated on a dense first substrate 10, wherein this step is performed on the first substrate 10. The upper layer is the curtain cover layer 11 and is further used on the curtain and using photo-etching technology on the first ′ and through the first opening 13 and used

Page 7 560028 V. Description of the invention Plasma etching technology etches the curtain cover layer 11 to form a curtain cover opening 14 on the curtain cover layer i 丨. After the first photoresist layer i 2 is removed, the curtain is etched through The cover layer i uses a wet anisotropic etching technique to etch a recess on the first substrate. ^ 5 ^ Please refer to FIG. 11 and FIG. 12, and deposit a thin film on the first substrate 10. The seed layer 16 is deposited as a conductive layer, and a metal layer 17 is plated on the seed layer 16 by electroplating a metal layer. The metal layer 17 may be nickel (Ni) or nicked nickel (NiCo). Metal material, and the surface of the metal layer 17 is purified. The passivation method is oxygen plasma, natural ox idat ion, chemical reaction, electrochemical reaction. Electrochemical reaction, wherein the chemical reaction system can use hydrogen peroxide to chemically react with the metal layer 17 to form the passivation layer 18. Please refer to FIG. 13 and FIG. 14. Then, a second photoresist layer 19 is coated on the surface of the first substrate 10, and the second photoresist layer 19 is defined by using photo-etching technology. A second opening 20, and the second opening 20 is connected to the recessed portion 15 so as to use the second opening 20 to define a region of the metal cover 30. Finally, a metal layer is plated on the first substrate 10 The passivation layer 18 is plated with a metal cover layer as a metal cover 30 to encapsulate the micro-electromechanical element 50. Please refer to the sixth, fifteenth to seventeenth figures, and the second substrate 4 0 A circuit layer 41 is fabricated thereon, and the micro-electro-mechanical element 50 is disposed on the first substrate 40. The micro-electro-mechanical element 50 is electrically connected to the circuit layer 41, so that the metal cover 30 is covered. When on the second substrate 40, the circuit layer 41 560028 5. Description of the invention (6) is the electrical connection of the microelectromechanical element 50 to the external connection, and an insulating layer 4 2 is provided on the circuit layer 41 And deposit a multilayer metal film 43 (commonly referred to as UBM, Under Bump M) in a thin film deposition manner at a predetermined position of the insulating layer etallurgy), the multilayer metal film 43 is a composite plating layer such as chromium / gold (Cr / Au) or titanium / gold (Ti / Au), and the bumps 44 are plated on the multilayer metal film 43 by electroplating. The bump 44 is a solder material. Please refer to the eighteenth and nineteenth figures, and then use the double-sided alignment technology to align the first substrate 10 and the second substrate 40, and use the eutectic bonding technology to seal the metal seal 30 and the second substrate The bumps 44 on the substrate 40 are bonded, and the passivation layer 18 of the first substrate 10 is provided, so that the metal cap μ is easily separated from the first substrate 10, so that the metal cap 30 is bonded to the 40 The bump 44 is formed on the bump 44 to form a micro-electromechanical device package. … The first substrate, please refer to FIG. 19 and FIG. 20, the above-mentioned substrates 10 and 40 can be wafers, so that the metal cap can be made on the first wafer 60, and The micro-electro-mechanical element 50 is disposed on the second wafer 61 for wafer-level packaging. After the metal cap 30 is bonded to the second wafer 61, the 60 is separated from the metal cap 30 and the first wafer is cut. Two wafers 61 to form a micro-electromechanical device package. The metal "the method for sealing and encapsulating micro-electromechanical elements of the present invention and its method of encapsulation" uses microlithography electroforming molding (liga technology = combined with integrated circuit packaging technology to perform microcomputers). A substrate is used as a conductive layer, a metal cap is made on a substrate, and a seed layer is used to facilitate the genus 44 ~ 9 ~ I 丄 F purification layer to facilitate the metal seal to escape from the first substrate, and the- Substrate can be repeatedly used

Page 9 560028 V. Description of the invention (7) The seed layer and the passivation layer need not be re-made, so that the manufacturing process of the sealed package of the micro-electromechanical component is shortened and the processing time is reduced, thus reducing the cost. However, the above are only the preferred and feasible embodiments of the present invention, and are not intended to limit the scope of the patent of the present invention. Therefore, any equivalent structural changes made by using the description and illustration contents of the present invention are included in the same reason. Within the scope of the present invention, Chen Ming is given.

Page 560028 Brief description of the diagrams Figures-Figures 5 to 5 are the flow chart of the sealing method of the TL component sealing drawing of the conventional city of Yicheng. The sixth figure is the micro-electromechanical element of the present invention ^ The seventh to tenth figures are the body d Top view of the process of making a recess on a substrate ® In the encapsulation method, the tenth to the tenth figure are the tenth method of the micro-electromechanical production of the present invention. The second method is the tenth method of making a metal cap on the substrate. Figures 5 to 19 are the micro-electro-mechanical components of the present invention: a flow chart of the process diagram. The package method of the tens of thousands of packages is a diagram of the wafer-level micro-electro-mechanical components of the present invention. Shi Xijing substrate 10a curtain cover layer 11a opening 12a recess 13a microelectromechanical device 2 〇a second silicon substrate 30a electrical connection point 3 1 a metal thin film 32a bump 3 3 a first substrate 10 curtain of the present invention Cover layer 11 First photoresist layer i 2 First opening 1 3 Curtain opening 1 4 Recess 15 Seed layer 1 6 Metal layer 1 7 Passivation layer 1 8 Second photoresist layer 1 9 Second opening 2 〇1ΜΪ Page 11 560028 Schematic illustration of metal cover 3 0 Second substrate 40 Circuit layer 41 Insulation layer 42 Multi-layer Metal thin film 43 bump 44

MEMS component 50 First wafer 6 0 Second wafer 6 1

Page 12

Claims (1)

The S6Q02S Mm micro-electromechanical components provide the first deposition seed to make blunt & metal package packaging. The steps for applying the special metal seals are layered on top of each other through the screen. The metal sealing step is to apply four special surfaces, such as applying a special metal sealing step to applying an electrochemical treatment, such as applying for a special substrate. The layer is formed on the cover layer, and the cover is covered with a metal seal. The method is to form the curtain cover and the first cover opening. The method is a metal cap manufacturing method of a blunt range sealing and sealing method, which is a method of plating a thin range of the favorable range and a method of plating, and a recess is formed on the step; a first substrate; the seed layer. On; and on the passivation layer as a cover. The following is the micro-electromechanical element described in Item 1 of Mystery Mechatronics 7L, which is described in the middle. The part is sealed in the sealing method to form a curtain layer on the recessed layer of the first substrate t and form a first opening. ϊΐ 1 coating the X-th opening on the first light P and the opening to etch the curtain cover layer to form a curtain cover opening, and # 2 to etch the first substrate to form the recess. The method for sealing and encapsulating a micro-electromechanical device according to item 2 ′, wherein the curtain layer is made of oxide or nitride. The method for sealing and packaging a micro-electromechanical element according to item 1, wherein the seed layer is deposited on the first substrate as a conductive layer by depositing a product of the seed layer on the first substrate. The method for sealing and encapsulating a micro-electromechanical element according to item 1, wherein a step of depositing a passivation layer on the seed layer and depositing a metal layer on the seed layer is performed, and then the metal layer is passivated to form a passivation layer. Method for sealing and encapsulating micro-electromechanical components according to item 5 Page 13 560028 6. Scope of patent application "--^ metal cap manufacturing method, wherein the metal layer is a metal layer of nickel (Nn NiCo). ) Or palladium nickel (7. The method for manufacturing a metal cap for a micro-electromechanical device seal as described in item 5 of the scope of the patent application, wherein the passivation method * is to make the metal by using the 02 plasma. A gas passivation layer is formed on the layer. Gas, gas and electricity 8. The method for manufacturing a micro-electromechanical element seal, a dream seal, and a metal cap as described in item 5 of the scope of the patent application, wherein the passivation treatment method uses a natural Oxidation) causes the metal layer to form a passivation sound. Gas 9. The metal cap manufacturing method of the method for sealing and sealing micro-electro-mechanical elements according to item 5 of the scope of patent application, wherein the purification treatment method uses a chemical reaction (Chemical reaction ) The metal layer is formed with the passivation layer. I 0 · The metal cap manufacturing method of the micro-electromechanical element sealing and sealing method described in item 9 of the scope of the application for patent, wherein the chemical reaction ion uses hydrogen peroxide and The metal layer reacts, so that the metal layer is formed with the passivation layer. II. The metal cap manufacturing method of the micro-electro-mechanical device sealing and encapsulation method described in item 5 of the patent application scope, wherein the purification treatment is The formula uses an electrochemical reaction to form the metal layer with the purification layer. 1 2 · The metal cap manufacturing method of the micro-electromechanical element sealing and packaging method as described in the first item of the patent application scope, wherein the The step of forming the metal cover layer on the passivation layer further includes coating a first photoresist layer on the passivation layer and forming a second opening on the second photoresist layer. The second opening is in communication with the recess. To define the shape of the metal cover. Page 14 560028 • Patent application scope ^^ ^ 13 • The metal cap manufacturing method for sealing micro-electromechanical components as described in item 1 of the patent application scope, wherein the first substrate is made of silicon S, and is round. Chip or silicon crystal 14. The method for manufacturing a metal cap for a micro-electro-mechanical device seal as described in item 1 of the scope of patent application, wherein the inner side of the metal cap is a & mounting method 15. A method for sealing and packaging a micro-electro-mechanical device The metal cap manufacturing method, cavity. The steps are: /, forming a curtain layer on the first substrate; coating a first photoresist layer on the curtain layer, and forming a first opening on the first photoresist layer; and passing through the first opening to Etch the curtain cover layer and form a curtain cover opening on the curtain cover layer; etch the first substrate through the curtain cover opening and form a recess on the first substrate; $ deposit a seed layer on the first substrate On the seed layer, passivate the metal layer to form a passivation layer; coat a second photoresist layer on the passivation layer, and form a second opening on the first layer Two photoresist layers are used to define the shape of the metal cover; and a metal cover layer is deposited on the passivation layer as a metal cover through the second opening. 16. The metal cap manufacturing method of the micro-electromechanical element sealing and packaging method according to item 15 of the scope of application for patent, wherein before the step of etching the first substrate through the opening of the curtain cover and forming a recess on the first substrate, And more 560028 6. Scope of Patent Application A further step includes removing the first photoresist layer. 1 7 · The metal cap manufacturing method for the sealing and sealing method of the micro-electromechanical element as described in item 15 of the patent application scope, wherein the curtain layer is made of silicon oxide or 2 ^^ 18. The method for sealing and packaging a micro-electromechanical device according to the item, and the metal cap manufacturing method, wherein the first substrate is a silicon wafer ^ a stone evening wafer. 19. The metal cap manufacturing method of the micro-electromechanical element sealing and packaging method according to item 15 of the scope of patent application, wherein the inner side of the metal cover is a cavity 002. A method for manufacturing a metal cap for an encapsulation method of an electromechanical element, wherein the step of depositing the metal layer on the seed layer is to deposit and deposit the metal layer on the seed layer by electroplating, and the metal layer is nickel (Ni) or Nickel cobalt (Nico). 21 · The metal cap manufacturing method of the method for sealing and encapsulating a micro-electromechanical element according to item 5 of the patent application scope, wherein a first photoresist layer is coated on the purification layer, and a second opening is formed on the second photoresist In the step of defining the shape of the metal cover, the second opening is in communication with the recess of the first substrate. 2 2 · The metal cap manufacturing method of the method for sealing and encapsulating a micro-electromechanical element according to item 5 of the patent application scope, wherein the step of depositing a metal cap layer on the passivation layer through the second opening is a method of electroplating a metal layer The metal cover layer is formed on the first substrate. 2 3 · Micro-electro-mechanical component sealed package as described in item 15 of the scope of patent application 560028 6. The metal cap manufacturing method of the scope of patent application, wherein the passivation treatment method uses an oxygen plasma (02 Plasma) to form the metal layer with the purification layer. 2 4. The metal cap manufacturing method of the micro-electro-mechanical element sealing and packaging method according to item 15 of the scope of the patent application, wherein the passivation treatment method uses natural oxidation to form the metal layer with the passivation layer. 2 5. The metal cap manufacturing method of the micro-electro-mechanical device sealing and encapsulation method according to item 15 of the scope of the patent application, wherein the passivation method uses a chemical reaction to form the metal layer with the passivation layer. 26. The metal cap manufacturing method of the micro-electromechanical element sealing and packaging method according to item 25 of the scope of the patent application, wherein the chemical reaction (Chemical reacti ο η) method uses hydrogen peroxide to react with the metal layer to form the metal layer There was this purified layer. 2 7 · The metal cap manufacturing method of the micro-electro-mechanical element sealing and packaging method as described in item 15 of the scope of patent application, wherein the passivation treatment method can use an electrochemical reaction to form the metal layer with the purification Floor. 2 8 · A method for sealing and packaging a micro-electromechanical element, the steps are: providing a first substrate with a recess formed thereon; depositing a seed layer on the first substrate; making a passivation layer on the seed layer; depositing a metal A cover layer is on the passivation layer to serve as a metal cover; providing a second substrate; Page 17 560028 6. The scope of the patent application is to set a micro-electromechanical element on the second substrate; deposit a multilayer metal film (UBM) around the micro-electromechanical element on the second substrate, and plated bumps on the multilayer metal film; Align the first substrate and the second substrate so that the metal cover layer is bonded to the bump; and 9 ~ remove the first substrate. 29. The method for sealing and encapsulating a micro-electromechanical element according to item 28 of the scope of patent application, wherein in the step of providing a first substrate and forming a recess thereon, a curtain layer is formed on the first substrate, and the first substrate is coated. A photoresist layer is formed on the screen cover layer to form a first opening on the first photoresist layer. The screen cover layer is etched through the first opening to form a screen cover opening, and the first mask is etched through the screen cover opening. A substrate to form the recess. 30. The method for sealing and encapsulating a micro-electromechanical device according to item 29 of the scope of the patent application, wherein the curtain layer is silicon oxide or silicon nitride. " 31. The method for sealing and encapsulating a micro-electromechanical device as described in item 28 of the scope of patent application, wherein the step of depositing the seed layer on the surface of the first substrate and < making a passivation layer on the seed layer is performed by The seed layer is deposited on the surface of the first substrate as a conductive layer by a thin film deposition method, and a metal layer is plated on the seed layer by electroplating, and the passivation process is used to form the metal layer with the passivation. Floor. 32. The method for sealing and encapsulating a micro-electromechanical device according to item 31 of the scope of application for a patent, wherein the metal layer is made of nickel (Ni) or nickel cobalt (Nico). 33. The method for sealing and encapsulating a micro-electromechanical device according to item 31 of the scope of the patent application, wherein the passivation treatment can be performed using an oxygen plasma (02 plasma). 560. Patent application scope The metal layer is formed with the passivation layer. 34. The method for sealing and encapsulating a micro-electro-mechanical device according to item 31 of the scope of the patent application, wherein the passivation treatment is capable of forming the metal layer with the purification layer by using natural oxidative oxidation. 35. The method for sealing and encapsulating a micro-electromechanical device according to item 31 of the scope of patent application, wherein the passivation treatment can use a chemical reaction (Chemi cal react i on) to form the metal layer and have the purification layer. 36. The method for sealing and encapsulating a micro-electromechanical device according to item 35 of the scope of patent application, wherein the chemical reaction is a reaction of hydrogen peroxide with the metal layer to form the metal layer with the purification layer. 37. The method for sealing and encapsulating a micro-electromechanical device according to item 31 of the scope of application for a patent, wherein the purification treatment is to use an electrochemical reaction to form the metal layer with the purification layer. 3 8. The method for sealing and encapsulating a micro-electromechanical device according to item 28 of the scope of the patent application, wherein the step of depositing the metal cover layer on the passivation layer further comprises coating a second photoresist layer on the passivation layer, A second opening is formed on the second photoresist layer, and the second opening is in communication with the recess to define the shape of the metal cover. 3 9 · The method for sealing and encapsulating a micro-electromechanical device according to item 28 of the scope of patent application, wherein the step of depositing the metal cover layer on the passivation layer is a method of plating a metal cover layer on the passivation layer by using the plating metal layer to the passivation On the floor. 40. The method for sealing and encapsulating a micro-electro-mechanical device according to item 28 of the scope of patent application, wherein the micro-electro-mechanical device is disposed before the step on the second substrate. Page 19 560028 A circuit layer is further arranged. The circuit layer is two ... then; the element; on the insulating substrate ', and the micro-electromechanical element is electrically connected to the circuit layer. The circuit layer is used as an electrical connection for external connection. 41. The method for sealing and packaging a micro-electro-mechanical device as described in item 28 of the scope of patent application, wherein the bump is a solder bump. ^ 42. The method for sealing and packaging micro-electro-mechanical components according to item 28 of the scope of application for patents, wherein the above-mentioned substrate is a silicon wafer or a silicon wafer. 43. The method for sealing and packaging a micro-electromechanical device according to item 28 of the scope of application for a patent, wherein the above-mentioned substrate is a wafer, which is suitable for wafer-level packaging, and further includes a step of removing the first substrate and further including The second substrate is cut to form individual microelectromechanical device packages.