Microelectro-mechanical systems (MEMS) microphone package device and MEMS packaging method thereof

Abstract

A MEMS microphone package device includes a MEMS microphone chip as an integrated circuit chip. An acoustic sensing structure is embedded in the integrated circuit chip. An adhesive structure adheres on outer sidewall of the microphone chip. A bottom portion of the adhesive structure protrudes out from first surface of the microphone chip and adheres on a surface of a substrate, having interconnection structure, to form a first seal ring. A space between the acoustic sensing structure and the substrate and sealed by the first seal ring forms a second chamber. A cover adheres to top portion of the adhesive structure, covering over the cavity on the second surface of the microphone chip. The top portion of the adhesive structure forms as a second seal ring. A space between the cover and the second surface of the microphone chip and sealed by the second seal ring forms a first chamber.

What is claimed is: 
     
       1. A micro-electromechanical systems (MEMS) microphone package device, comprising:
 a silicon MEMS microphone chip, wherein the silicon MEMS microphone chip is an integrated circuit chip and an acoustic sensing structure embedded in the integrated circuit chip, wherein the silicon MEMS microphone chip has a first surface and a second surface, wherein an integrated circuit and one side of an acoustic sensing structure of the silicon MEMS microphone chip are exposed at the first surface, wherein acoustic signals are received by the acoustic sensing structure and transferred to electrical signals via the integrated circuit, wherein a cavity is formed at the second surface of the silicon MEMS microphone chip to expose the other side of the acoustic sensing structure on the second surface of the silicon MEMS microphone chip; 
 a substrate, having an interconnection structure in the substrate; 
 an adhesive structure, adhering on an outer sidewall of the silicon MEMS microphone chip, wherein a bottom portion of the adhesive structure protrudes out from the first surface of the silicon MEMS microphone chip and adheres on a surface of the substrate to form a first seal ring, wherein a space between the acoustic sensing structure and the substrate and sealed by the first seal ring forms a second chamber; and 
 a cover, adhering to a top portion of the adhesive structure, covering over the cavity on the second surface of the silicon MEMS microphone chip, wherein the top portion of the adhesive structure forms as a second seal ring, wherein a space between the cover and the second surface of the silicon MEMS microphone chip and sealed by the second seal ring forms a first chamber, wherein the cavity is connected to the first chamber acoustically. 
 
     
     
       2. The MEMS microphone package device of  claim 1 , wherein the silicon MEMS microphone chip servers as a first MEMS microphone package unit as a single unit, or the MEMS microphone package device further comprises at least one second MEMS microphone package unit with a same structure defined in the first MEMS microphone package unit, wherein the two MEMS microphone package units communicate to each other by an additional portion of the interconnection structure in the substrate. 
     
     
       3. The MEMS microphone package device of  claim 2 , wherein the cover has an acoustic aperture to receive an acoustic source, and the acoustic aperture is at a location aligned to or shifted from the cavity of the silicon MEMS microphone chip. 
     
     
       4. The MEMS microphone package device of  claim 3 , wherein the acoustic aperture is at the location shifted from the cavity in silicon MEMS microphone chip, and the silicon MEMS microphone chip has an acoustic channel for guiding the acoustic source received from the acoustic aperture to the cavity. 
     
     
       5. The MEMS microphone package device of  claim 3 , wherein the substrate has an indent space under the acoustic sensing structure in silicon MEMS microphone chip to serve as a part of the second chamber for increasing volume. 
     
     
       6. The MEMS microphone package device of  claim 3 , wherein the interconnection structure in the substrate is electrically connecting to the integrated circuit embedded in the silicon MEMS microphone chip. 
     
     
       7. The MEMS microphone package device of  claim 6 , wherein the interconnection structure also includes at least one connection pad on a surface of the substrate, exposed to an environment for external connection. 
     
     
       8. The MEMS microphone package device of  claim 3 , wherein the cover is a cap-like structure so as to increase a volume of first chamber, and the substrate has an acoustic aperture to receive an acoustic source into the second chamber, and the acoustic aperture is at a location aligned to or shifted from the acoustic sensing structure of the silicon MEMS microphone chip. 
     
     
       9. The MEMS microphone package device of  claim 8 , wherein the substrate has an indent space under the acoustic sensing structure to serve as a part of the second chamber for increasing volume. 
     
     
       10. The MEMS microphone package device of  claim 8 , wherein the interconnection structure in the substrate is electrically connecting to the integrated circuit embedded in the silicon MEMS microphone chip. 
     
     
       11. The MEMS microphone package device of  claim 10 , wherein the interconnection structure also includes at least one connection pad on a surface of the substrate, exposed to an environment for external connection. 
     
     
       12. A micro-electromechanical systems (MEMS) microphone packaging method, comprising:
 providing a substrate, having a first surface and a second surface, wherein the substrate has been predetermined with a plurality packaging units, an interconnection structure is formed in the substrate corresponding each of the packaging units, wherein the interconnection structure has a plurality of first connecting pads on the first surface and a plurality of second connection pads on the second surface; 
 adhering a plurality of silicon MEMS microphone chips to the packaging units on the first connecting pads by conductive adhesive material on the first connection pads; 
 forming an adhesive structure, adhering on an outer sidewall of each of the silicon MEMS microphone chips, wherein a bottom portion of the adhesive structure in each of the silicon MEMS microphone chips protrudes out from a bottom of the silicon MEMS microphone chips and adheres on the first surface of the substrate to form a first seal ring in close form, and a top portion of the adhesive structure in each of the silicon MEMS microphone chips protrudes out from a top of the silicon MEMS microphone chips; 
 forming a plurality of covers; 
 adhering the covers respectively to the silicon MEMS microphone chips on the top portion of the adhesive structure, wherein a second seal ring in close form corresponding to each of the silicon MEMS microphone chips is formed; and 
 singulating the packaging units into a plurality of single-device chips. 
 
     
     
       13. The MEMS microphone packaging method of  claim 12 , wherein each of the packaging units is configured to adapt at least one of the silicon MEMS microphone chips, wherein if two or more of the silicon MEMS microphone chips are configured, the multiple silicon MEMS microphone chips communicate to one another by an additional portion of the interconnection structure in the substrate. 
     
     
       14. The MEMS microphone packaging method of  claim 13 , wherein the step of forming the covers comprises forming an acoustic aperture in each of the covers to receive an acoustic source, and the acoustic aperture is at a location aligned to or shifted from an cavity in each of the silicon MEMS microphone chips, the cavity is coupled to the acoustic sensing structure. 
     
     
       15. The MEMS microphone packaging method of  claim 14 , wherein the acoustic aperture is at the location shifted from the cavity in each of the silicon MEMS microphone chips, and each of the silicon MEMS microphone chips has an acoustic channel for guiding the acoustic source received from the acoustic aperture to the cavity. 
     
     
       16. The MEMS microphone packaging method of  claim 13 , wherein the substrate also has an indent space within each of the first seal rings. 
     
     
       17. The MEMS microphone packaging method of  claim 13 , wherein the interconnection structure in the substrate is electrically connecting to an integrated circuit embedded in each of the silicon MEMS microphone chips. 
     
     
       18. The MEMS microphone packaging method of  claim 13 , wherein the second connecting pads are exposed to an environment for external connection. 
     
     
       19. The MEMS microphone packaging method of  claim 13 , wherein the cover formed in the step of forming the covers is a cap-like structure, and the substrate has an acoustic aperture corresponding to each of the silicon MEMS microphone chip to receive an acoustic source, wherein the acoustic aperture is at a location aligned to or shifted from a cavity of each of the silicon MEMS microphone chips, and the cavity is connected to an acoustic sensing structure acoustically. 
     
     
       20. The MEMS microphone packaging method of  claim 19 , wherein the substrate further has an indent space within each of the first seal rings. 
     
     
       21. The MEMS microphone packaging method of  claim 19 , wherein the interconnection structure in the substrate for each of the silicon MEMS microphone chip s is electrically connecting to an integrated circuit embedded in each of the silicon MEMS microphone chips.