Fingerprint sensor device and method

• US 10,268,872 B2
• Filed: 02/19/2018
• Issued: 04/23/2019
• Est. Priority Date: 11/17/2015
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Huang, Yu-Chih, Chen, Chih-Hua, Cheng, Yu-Jen, Lin, Chih-Wei, Chen, Yu-Feng, Tsai, Hao-Yi, Liu, Chung-Shi, Yu, Chen-Hua
• Primary Examiner(s): Potter, Roy K
• Application Number:
  US15/898,871
• Publication Number:
  US 20180173932A1
• Time in Patent Office: 428 Days
• CPC Class Codes: G06V 40/1329 Protecting the fingerprint sensor against damage caused by the finger
• CPC Class Codes: H01L 21/561 Batch processing
• CPC Class Codes: H01L 21/568 Temporary substrate used as encapsulation process aid H01L21/4832 and H01L21/566 take precedence
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/04105 Bonding areas formed on an encapsulation of the semiconductor or solid-state body, e.g. bonding areas on chip-scale packages
• CPC Class Codes: H01L 2224/12105 Bump connectors formed on an encapsulation of the semiconductor or solid-state body, e.g. bumps on chip-scale packages
• CPC Class Codes: H01L 2224/13111 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2224/18 High density interconnect [HDI] connectors; Manufacturing methods related thereto
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/73267 Layer and HDI connectors
• CPC Class Codes: H01L 2224/81 using a bump connector
• CPC Class Codes: H01L 2224/81005 being a temporary or sacrificial substrate
• CPC Class Codes: H01L 2224/81024 Applying flux to the bonding area
• CPC Class Codes: H01L 2224/81815 Reflow soldering
• CPC Class Codes: H01L 2224/81911 : Chemical cleaning, e.g. etching, flux
• CPC Class Codes: H01L 2224/83 : using a layer connector
• CPC Class Codes: H01L 2224/83005 : being a temporary or sacrificial substrate
• CPC Class Codes: H01L 2224/85 : using a wire connector
• CPC Class Codes: H01L 2224/85005 : being a temporary or sacrificial substrate
• CPC Class Codes: H01L 2224/92125 : the second connecting process involving a layer connector
• CPC Class Codes: H01L 2224/92244 : the second connecting process involving a build-up interconnect
• CPC Class Codes: H01L 2224/97 : the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 23/49827 : Via connections through the substrates, e.g. pins going through the substrate, coaxial cables H01L23/49822, H01L23/49833, H01L23/4985, H01L23/49861 take precedence
• CPC Class Codes: H01L 24/13 : of an individual bump connector
• CPC Class Codes: H01L 24/16 : of an individual bump connector
• CPC Class Codes: H01L 24/19 : Manufacturing methods of high density interconnect preforms
• CPC Class Codes: H01L 24/32 : of an individual layer connector
• CPC Class Codes: H01L 24/45 : of an individual wire connector
• CPC Class Codes: H01L 24/48 : of an individual wire connector
• CPC Class Codes: H01L 24/73 : Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 24/81 : using a bump connector
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• 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: H01L 2924/15311 : being a ball array, e.g. BGA

Abstract

A fingerprint sensor package and method are provided. Embodiments include a sensor and a sensor surface material encapsulated within the fingerprint sensor package. An array of electrodes of the sensor are electrically connected using through vias that are located either in the sensor, in connection blocks separated from the sensor, or through connection blocks, or else connected through other connections such as wire bonds. A high voltage die is attached in order to increase the sensitivity of the fingerprint sensor.

Claims

1. A method of manufacturing a fingerprint scanner, the method comprising:

placing a sensor surface material onto a sensor, the sensor surface material having a first width less than a second width of the sensor;

placing the sensor face-up onto a redistribution layer;

connecting a first contact pad of the sensor to a conductive surface of the redistribution layer, the conductive surface being laterally separated from the sensor;

encapsulating the sensor with an encapsulant; and

bonding a high voltage chip to the redistribution layer.

2. The method of claim 1, wherein the connecting the first contact pad of the sensor to the conductive surface of the redistribution layer comprises attaching a wire bond between the first contact pad and the conductive surface.

3. The method of claim 2, wherein the encapsulating the sensor encapsulates the wire bond.

4. The method of claim 1, wherein after the encapsulating the sensor the encapsulant is planar with the sensor surface material.

5. The method of claim 1, further comprising attaching first external connections to the redistribution layer.

6. The method of claim 5, wherein the first external connections extend away from the redistribution layer further than the high voltage chip.

7. The method of claim 1, wherein the high voltage chip is bonded to the redistribution layer directly over the sensor.

8. A method of manufacturing a fingerprint sensor, the method comprising:

placing a connection block next to a sensor, the connection block comprising a via that extends a portion of a way through the connection block;

connecting the via to the sensor through a first redistribution layer;

thinning a surface of the connection block to expose the via and form a thinned surface, the surface of the connection block being on an opposite side of the connection block from the first redistribution layer;

forming a second redistribution layer adjacent to the thinned surface of the connection block; and

connecting a high voltage chip to the sensor through the second redistribution layer, the via, and the first redistribution layer.

9. The method of claim 8, further comprising encapsulating the connection block and the sensor with an encapsulant.

10. The method of claim 9, wherein the thinning the surface of the connection block thins the encapsulant.

11. The method of claim 10, wherein after the thinning the surface of the connection block the connection block, the encapsulant, and the sensor are planar with each other.

12. The method of claim 8, further comprising connecting first external connections to the second redistribution layer.

13. The method of claim 12, wherein the first external connections extend away from the second redistribution layer further than the high voltage chip.

14. The method of claim 8, further comprising placing an underfill material between the high voltage chip and the second redistribution layer.

15. A fingerprint sensor comprising:

a sensor;

a first redistribution layer adjacent a first side of the sensor;

a second redistribution layer adjacent a second side of the sensor opposite the first side of the sensor;

a high voltage chip connected to the first redistribution layer;

a via connecting the first redistribution layer and the second redistribution layer, wherein the via extends through a connection block; and

an encapsulant separating the connection block from the sensor.

16. The fingerprint sensor of claim 15, further comprising a sensor surface material adjacent to the second redistribution layer.

17. The fingerprint sensor of claim 15, wherein the connection block has a first surface planar with the encapsulant.

18. The fingerprint sensor of claim 17, wherein the connection block has a second surface planar with the encapsulant, the second surface opposite the first surface.

19. The fingerprint sensor of claim 18, wherein the second surface is planar with the sensor.

20. The fingerprint sensor of claim 15, further comprising external connections connected to the first redistribution layer, wherein the external connections have a first height larger than a second height of the high voltage chip.