Electronic devices including substantially hermetically sealed cavities and getter films with Kelvin measurement arrangement for evaluating the getter films and methods for fabricating the same

Patent metadata

Field	Value
Publication number	US-9718672-B2
Application number	US-201514985093-A
Country	US
Kind code	B2
Filing date	Dec 30, 2015
Priority date	May 27, 2015
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

Electronic devices and methods for fabricating electronic devices are provided. In one example, an electronic device includes an electronic device body structure having a substantially hermetically sealed cavity formed therein. A getter film is in fluid communication with the substantially hermetically sealed cavity. Conductive features are accessible from outside the substantially hermetically sealed cavity and are operatively coupled to the getter film for electrical communication with the getter film.

First claim

What is claimed is:

1. An electronic device comprising:
an electronic device body structure having a substantially hermetically sealed cavity formed therein;
a getter film in fluid communication with the substantially hermetically sealed cavity;
conductive features accessible from outside the substantially hermetically sealed cavity and operatively coupled to the getter film for electrical communication with the getter film; and
a Kelvin measurement arrangement in electrical communication with the electronic device for evaluating the getter film.

2. The electronic device of claim 1 , wherein the electronic device is configured as a micro-electro-mechanical system (MEMS) device.

3. The electronic device of claim 1 , wherein the getter film is activated to effectively absorb and/or adsorb gas to produce and/or maintain a vacuum condition in the substantially hermetically sealed cavity.

4. The electronic device of claim 1 , wherein the conductive features comprise a plurality of conductive vias electrically coupled to the getter film and extending in and through the electronic device body structure.

5. The electronic device of claim 4 , wherein the electronic device body structure has an outer surface and the conductive vias extend between the outer surface and the getter film that is disposed over an inner surface of the electronic device body structure, and wherein the conductive features further comprise a plurality of conductive pads overlying the outer surface and electrically coupled to the conductive vias for electrical communication with the getter film.

6. The electronic device of claim 1 , wherein the getter film is disposed in the substantially hermetically sealed cavity.

7. A method for fabricating an electronic device, the method comprising:
providing an electronic device body structure having a substantially hermetically sealed cavity formed therein;
providing a getter film in fluid communication with the substantially hermetically sealed cavity;
providing conductive features accessible from outside the substantially hermetically sealed cavity and operatively coupled to the getter film for electrical communication with the getter film;
activating the getter film that is in fluid communication with the substantially hermetically sealed cavity in the electronic device body structure of the electronic device to form an activated getter film; and
determining a resistance of the activated getter film using a Kelvin measurement arrangement in electrical communication with the electronic device for evaluating if the activated getter film can effectively absorb and/or adsorb gas to produce and/or maintain a vacuum condition in the substantially hermetically sealed cavity.

8. The method of claim 7 , further comprising determining a first resistance (R 1 ) of the getter film before activating the getter film, and wherein determining the resistance of the activated getter film comprises:
determining a second resistance (R 2 ) of the activated getter film initially after activating the getter film, and wherein the method further comprises:
comparing R 2 with R 1 to determine if the activated getter film can effectively absorb and/or adsorb gas to produce and/or maintain the vacuum condition in the substantially hermetically sealed cavity.

9. The method of claim 8 , wherein comparing R 2 with R 1 comprises determining that the activated getter film can effectively absorb and/or adsorb gas when R 2 >R 1 .

10. The method of claim 8 , wherein determining R 1 comprises;
applying a first static current I 1 to the getter film and measuring in response a first voltage V 1 ; and
calculating R 1 using the relationship R 1 =V 1 /I 1 , and wherein determining R 2 comprises:
applying a second static current I 2 to the activated getter film and measuring in response a second voltage V 2 ; and
calculating R 2 using the relationship R 2 =V 2 /I 2 .

11. The method of claim 8 , wherein determining the resistance of the activated getter film comprises:
determining a third resistance (R 3 ) of the activated getter film after making measurements for determining R 2 , and wherein comparing R 2 with R 1 further comprises comparing R 2 with R 3 .

12. The method of claim 11 , wherein comparing R 1 , R 2 , and R 3 comprises determining that the activated getter film can effectively absorb and/or adsorb gas when R 3 >R 2 >R 1 .

13. The method of claim 11 , wherein determining R 2 comprises measuring an initial electrical response from an initial electrical input to the activated getter film, and wherein determining R 3 comprises;
measuring a subsequent electrical response from a subsequent electrical input to the activated getter film at a time of from about 5 to about 60 minutes after measuring the initial electrical response; and
using the subsequent electrical response for determining R 3 .

14. A method for fabricating an electronic device, the method comprises:
forming a getter film overlying a first portion of an electronic device body structure;
forming conductive features extending through the first portion of the electronic device body structure for operatively coupling the conductive features with the getter film for electrical communication with the getter film;
sealing the first portion of the electronic device body structure with a second portion of the electronic device body structure to form a substantially hermetically sealed cavity in the electronic device body structure such that the getter film is in fluid communication with the substantially hermetically sealed cavity and the conductive features are accessible from outside the substantially hermetically sealed cavity;
heating the electronic device body structure including the getter film after sealing the first portion with the second portion to activate the getter film to form an activated getter film for effectively absorbing and/or adsorbing gas to produce and/or maintain a vacuum condition in the substantially hermetically sealed cavity; and
using the conductive features, determining a resistance of the activated getter film using a Kelvin measurement arrangement in electrical communication with the electronic device for evaluating if the activated getter film can effectively absorb and/or adsorb gas to produce and/or maintain the vacuum condition in the substantially hermetically sealed cavity.

15. The method of claim 14 , wherein the first portion of the electronic device body structure has an outer surface and an inner surface that is on a side opposite the outer surface and that at least in part defines the substantially hermetically sealed cavity, wherein forming the getter film comprises forming the getter film overlying the inner surface of the first portion.

16. The method of claim 15 , wherein forming the conductive features comprises forming conductive vias extending between the inner and outer surfaces of the first portion for electrically coupling to the getter film.

17. The method of claim 16 , wherein forming the conductive features comprises forming conductive pads overlying the outer surface of the first portion electrically coupled to the conductive vias.

18. The method of claim 14 , further comprising, using the conductive features, determining a first resistance (R 1 ) of the getter film after sealing the first portion with the second portion and before heating the electronic device body structure, and wherein determining the resistance of the activated getter film comprises:
using the conductive features, determining a second resistance (R 2 ) of the ac

Assignees

• Globalfoundries Sg Pte Ltd

Inventors

• Goh Szu Huat
• Susanto Edy
• Lam Jeffrey

Classifications

• B81B7/0038 Primary

  using materials for controlling the level of pressure, contaminants or moisture inside of the package, e.g. getters · CPC title

• B81C1/00285 Primary

  using materials for controlling the level of pressure, contaminants or moisture inside of the package, e.g. getters · CPC title

• B81C99/004

  during manufacturing · CPC title