Catheter die and method of fabricating the same

• US 8,714,021 B2
• Filed: 02/27/2012
• Issued: 05/06/2014
• Est. Priority Date: 02/27/2012
• Status: Expired due to Fees

• Current Assignee: Amphenol Thermometrics, Inc. (Amphenol Corporation)
• Original Assignee: Amphenol Thermometrics, Inc. (Amphenol Corporation)
• Inventors: Gamage, Sisira Kankanam
• Primary Examiner(s): ALLEN, ANDRE J
• Application Number:
  US13/406,395
• Publication Number:
  US 20130220972A1
• Time in Patent Office: 799 Days
• US Class Current: 73/721
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/12 Manufacturing methods specially adapted for producing sensors for in-vivo measurements
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: B29C 2948/92019 Pressure
• CPC Class Codes: B29C 2948/92409 Die; Nozzle zone
• CPC Class Codes: B29C 2948/92514 Pressure
• CPC Class Codes: B29C 2948/92904 Die; Nozzle zone
• CPC Class Codes: B29C 48/92 Measuring, controlling or regulating
• CPC Class Codes: G01L 9/0045 Diaphragm associated with a buried cavity
• CPC Class Codes: G01L 9/0048 Details about the mounting of the diaphragm to its support or about the diaphragm edges, e.g. notches, round shapes for stress relief
• CPC Class Codes: G01L 9/0052 of piezoresistive elements circuits therefor G01L9/06
• CPC Class Codes: G01L 9/0054 integral with a semiconducting diaphragm
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48464 the other connecting portion not on the bonding area also being a ball bond, i.e. ball-to-ball
• CPC Class Codes: H01L 28/20 Resistors
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: Y10T 156/109 Embedding of laminae within face of additional laminae

Abstract

A catheter die is provided and includes a device layer defining a cavity and including a piezoresistive pressure sensor operably disposed proximate to the cavity and an insulator having an opening and being disposed on an upper surface of the device layer such that a portion of the piezoresistive pressure sensor is exposed through the opening. The catheter die further includes an insulation layer bonded to a lower surface of the device layer and first and second bond pads, the first bond pad being electrically coupled to the portion of the piezoresistive pressure sensor via the opening and the second bond pad being disposed on the insulation layer.

Claims

1. A catheter die, comprising:

a device layer defining a cavity and including a piezoresistive pressure sensor operably disposed proximate to the cavity and an insulator having an opening and being disposed on an upper surface of the device layer such that a portion of the piezoresistive pressure sensor is exposed through the opening;

an insulation layer bonded to a lower surface of the device layer;

first and second bond pads, the first bond pad being electrically coupled to the portion of the piezoresistive pressure sensor via the opening and the second bond pad being disposed on the insulation layer.

2. The catheter die according to claim 1, wherein the insulation layer is formed to define vent channels fluidly communicative with the cavity.

3. The catheter die according to claim 1, wherein a thickness of the device layer is approximately 390 μ

m or less.

4. The catheter die according to claim 1, wherein a thickness of the insulation layer is approximately 390 μ

m or less.

5. The catheter die according to claim 1, wherein the device layer comprises silicon and the insulation layer comprises glass.

6. A catheter die, comprising:

a device layer defining a cavity and including a piezoresistive pressure sensor operably disposed proximate to the cavity and an insulator having an opening and being disposed on an upper surface of the device layer such that a portion of the piezoresistive pressure sensor is exposed through the opening;

an insulation layer bonded to the lower surface of the device layer;

a first bond pad electrically coupled to the portion of the piezoresistive pressure sensor via the opening;

a second bond pad disposed on the insulation layer and electrically coupled to the first bond pad via wiring; and

an external connector electrically coupled to the second bond pad at a distance from the wiring.

7. The catheter die according to claim 6, wherein the insulation layer is formed to define vent channels fluidly communicative with the cavity.

8. The catheter die according to claim 6, wherein a thickness of the device layer is approximately 390 μ

m or less.

9. The catheter die according to claim 6, wherein a thickness of the insulation layer is approximately 390 μ

m or less.

10. The catheter die according to claim 6, wherein the first device layer comprises at least one of an n-type and a p-type semi-conductor, the second device layer comprises an n-type semi-conductor and the insulation layer comprises glass.

11. The catheter die according to claim 6, wherein the distance between the external connector and the wiring is 1 mm or more.

12. A method of fabricating a catheter die, comprising:

forming, in a device layer having upper and lower surfaces, a cavity recessed from at least the upper surface and a piezoresistive pressure sensor operably disposed proximate to the cavity;

disposing an insulator having an opening on the device layer to expose a portion of the piezoresistive pressure sensor;

bonding an insulation layer to the lower surface of the device layer; and

electrically coupling a first bond pad to the portion of the piezoresistive pressure sensor via the opening and disposing a second bond pad on the insulation layer.

13. The method according to claim 12, wherein the forming of the cavity comprises at least one or more of wet and dry etching.

14. The method according to claim 12, wherein the disposing of the insulator comprises at least one or more of depositing and growing a passivation layer.

15. The method according to claim 12, wherein the forming of the piezoresistive pressure sensor comprises at least one or more of dopant diffusion and implantation.

16. The method according to claim 12, further comprising defining the opening by at least one or more of wet and dry etching.

17. The method according to claim 12, wherein the electrical coupling of the first bond pad to the portion of the piezoresistive pressure sensor comprises deposition processing.

18. The method according to claim 12, wherein the disposing of the second bond pad on the insulation layer is conducted prior to the bonding of the insulation layer to the lower surface of the device layer and comprises:

etching a first through-hole in the insulator; and

etching a second through-hole in the device layer.

19. The method according to claim 12, further comprising singulation processing.

20. The method according to claim 12, further comprising defining in the insulation layer vent channels fluidly communicative with the cavity.