Integrated imaging device for infrared radiation and method of production

Patent metadata

Field	Value
Publication number	US-2016104741-A1
Application number	US-201414889835-A
Country	US
Kind code	A1
Filing date	Apr 15, 2014
Priority date	May 8, 2013
Publication date	Apr 14, 2016
Grant date	—

Abstract

The integrated imaging device comprises a substrate ( 1 ) with an integrated circuit ( 4 ), a cover ( 2 ), a cavity ( 6 ) enclosed between the substrate ( 1 ) and the cover ( 2 ), and a sensor ( 5 ) or an array of sensors ( 5 ) arranged in the cavity ( 6 ). A surface ( 11, 12 ) of the substrate ( 1 ) or the cover ( 2 ) opposite the cavity ( 6 ) has a structure ( 8 ) directing incident radiation. The surface structure ( 8 ) may be a plate zone or a Fresnel lens focusing infrared radiation and may be etched into the surface of the substrate or cover, respectively.

First claim

1 . An integrated imaging device, comprising:
a substrate comprising an integrated circuit; a cover bonded to the substrate; a dielectric layer between the substrate and the cover; a sensor or an array of sensors; a cavity enclosed between the substrate and the cover; a surface of the substrate opposite the dielectric layer or a surface of the cover opposite the dielectric layer being provided with a structure directing incident radiation to the sensor or array of sensors; the sensor or the array of sensors being arranged in the cavity; the cavity being a vacuum or comprising a gas pressure of less than 100 Pa; at least one metallization layer being embedded in the dielectric layer; and at least one electrically conductive connection connecting the sensor or array of sensors to the metallization layer, the electrically conductive connection extending from the cavity into the dielectric layer.

2 . The integrated imaging device of claim 1 , wherein the surface structure is a zone plate for focusing infrared radiation.

3 . The integrated imaging device of claim 1 , wherein the surface structure is a single spherical lens or a Fresnel lens for focusing infrared radiation.

4 . The integrated imaging device of claim 1 , wherein the sensor or array of sensors comprises a diode having a pn junction formed in polysilicon.

5 . (canceled)

6 . The integrated imaging device of claim 1 , wherein the sensor or array of sensors comprises a membrane integrally formed with the electrically conductive connection.

7 . The integrated imaging device of claim 6 , wherein the membrane is electrically resistive.

8 . The integrated imaging device of claim 6 , wherein the membrane comprises a pn junction.

9 . The integrated imaging device of claim 1 , wherein the cavity extends into the substrate and into the cover.

10 . An integrated imaging device, comprising:
a substrate comprising an integrated circuit; a cover bonded to the substrate; a dielectric layer between the substrate and the cover; a sensor or an array of sensors; a cavity enclosed between the substrate and the cover; a surface of the substrate opposite the dielectric layer or a surface of the cover opposite the dielectric layer being provided with a structure directing incident radiation to the sensor or array of sensors; the sensor or the array of sensors being arranged in the cavity; the cavity being a vacuum or comprising a gas pressure of less than 100 Pa; and the cavity extending into the substrate and forming compartments separated by components of the integrated circuit, each sensor being arranged in or above one of the compartments.

11 . The integrated imaging device of claim 10 , wherein the cavity is arranged in the dielectric layer and extends into the cover.

12 . The integrated imaging device of claim 1 , further comprising:
at least one through-substrate via in the substrate, the through-substrate via electrically connecting the integrated circuit or the sensor or array of sensors with a connection pad on the surface of the substrate opposite the dielectric layer.

13 . The integrated imaging device of claim 12 , wherein
the through-substrate via is not filled with electrically conductive or dielectric material, and the cover is bonded to the substrate above the through-substrate via.

14 . (canceled)

15 . A method of producing an integrated imaging device, comprising:
providing a substrate with an integrated circuit, a dielectric layer and at least one metallization layer embedded in the dielectric layer, at least a surface of the dielectric layer being formed by a silicon oxide; arranging a sensor or an array of sensors on or above the substrate; forming at least one electrically conductive connection of the sensor or array of sensors to the metallization layer; applying a cover comprising silicon on the substrate by bonding, thus forming a cavity in which the sensor or array of sensors is arranged, the electrically conductive connection extending from the cavity into the dielectric layer; and etching a surface of the substrate opposite the dielectric layer or a surface of the cover opposite the dielectric layer to produce a structure directing incident radiation to the sensor or array of sensors.

16 . The method of claim 15 , wherein
the cavity is formed such that it comprises a vacuum or a gas pressure of less than 100 Pa.

17 . The method of claim 15 , wherein
the surface structure is etched to form a single spherical lens or a Fresnel lens.

18 . The method of claim 17 , wherein
the surface in which the lens is to be etched is covered with a patterning layer; the patterning layer is structured according to the lens; and the patterning layer is removed by an anisotropic etching process, which transfers the structure of the patterning layer into the surface.

19 . The method of claim 18 , wherein
the surface in which the lens is to be etched is silicon, and the patterning layer is formed from a polymer having the same etch rate as silicon.

20 . The method of claim 15 , further comprising:
the sensor or array of sensors being arranged in the dielectric layer; a recess being etched in the substrate under the sensor or array of sensors; and the dielectric layer being at least partially removed from the sensor or array of sensors.

21 . The method of claim 15 , further comprising:
the sensor or array of sensors being arranged on a sacrificial layer and in the dielectric layer; the sacrificial layer being removed; and the dielectric layer being at least partially removed from the sensor or array of sensors.

22 . The method of claim 15 , further comprising:
the sensor or array of sensors being formed including a membrane of polysilicon, which is integrally structured together with electrically conductive connections connecting the membrane to metallization layers in the dielectric layer.

23 . The method of claim 22 , further comprising:
providing the membrane with a pn junction.

24 . The integrated imaging device of claim 10 , wherein the surface structure is a zone plate for focusing infrared radiation.

25 . The integrated imaging device of claim 10 , wherein the surface structure is a single spherical lens or a Fresnel lens for focusing infrared radiation.

26 . The integrated imaging device of claim 10 , wherein the sensor or array of sensors comprises a diode having a pn junction formed in polysilicon.

27 . The integrated imaging device of claim 10 , wherein the sensor or array of sensors comprises a membrane integrally formed with the electrically conductive connection.

28 . The integrated imaging device of claim 27 , wherein the membrane is electrically resistive.

29 . The integrated imaging device of claim 28 , wherein the membrane comprises a pn junction.

Assignees

• Ams Ag

Inventors

• Enichlmair Hubert
• Minixhofer Rainer
• Schrems Martin

Classifications

• G01J5/0225

  Shape of the cavity itself or of elements contained in or suspended over the cavity · CPC title

• G01J5/048

  Protective parts · CPC title

• G01J2005/0077

  Imaging · CPC title

• G01J5/045

  Sealings; Vacuum enclosures; Encapsulated packages; Wafer bonding structures; Getter arrangements (getter arrangements per se H10W76/48, H10P36/03) · CPC title

• G01J5/022

  Monolithic · CPC title