Proximity detector device with interconnect layers and related methods

• US 10,326,039 B2
• Filed: 10/24/2018
• Issued: 06/18/2019
• Est. Priority Date: 04/28/2013
• Status: Active Grant

• Current Assignee: STMicroelectronics Incorporated (STMicroelectronics NV)
• Original Assignee: STMicroelectronics Incorporated (STMicroelectronics NV)
• Inventors: Luan, Jing-En
• Primary Examiner(s): Inoussa, Mouloucoulaye
• Application Number:
  US16/169,522
• Publication Number:
  US 20190058076A1
• Time in Patent Office: 237 Days
• Field of Search: 257 82, 257774, 257432, 438 25, 356614
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 17/08 for measuring distance only indirect measurement G01S17/46; active triangulation systems G01S17/48
• CPC Class Codes: G01S 7/4813 Housing arrangements
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 24/19 Manufacturing methods of high density interconnect preforms
• 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 2924/12041 LED
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 31/0203 Containers; Encapsulations , e.g. encapsulation of photodiodesfor photovoltaic devices H01L31/048; for organic photosensitive devices H10K30/80
• CPC Class Codes: H01L 31/02327 the optical elements being integrated or being directly associated to the device, e.g. back reflectors optical coatings H01L31/0216
• CPC Class Codes: H01L 31/173 formed in, or on, a common substrate

Abstract

A proximity detector device may include a first interconnect layer including a first dielectric layer, and first electrically conductive traces carried thereby, an IC layer above the first interconnect layer and having an image sensor IC, and a light source IC laterally spaced from the image sensor IC. The proximity detector device may include a second interconnect layer above the IC layer and having a second dielectric layer, and second electrically conductive traces carried thereby. The second interconnect layer may have first and second openings therein respectively aligned with the image sensor IC and the light source IC. Each of the image sensor IC and the light source IC may be coupled to the first and second electrically conductive traces. The proximity detector device may include a lens assembly above the second interconnect layer and having first and second lenses respectively aligned with the first and second openings.

Claims

1. A method of forming a proximity detector device, the method comprising:

forming a first interconnect layer comprising a plurality of first electrically conductive traces;

forming an integrated circuit (IC) layer over the first interconnect layer, the IC layer comprising;

an image sensor IC; and

a light source IC laterally spaced from the image sensor IC;

forming a second interconnect layer over the IC layer, the second interconnect layer comprising a plurality of second electrically conductive traces and first and second openings having sidewalls defined by dielectric material of the second interconnect layer, the first and second openings respectively aligned with the image sensor IC and the light source IC;

filling the first and second openings of the second interconnect layer with a transparent adhesive material, the transparent adhesive material physically contacting the image sensor IC and light source IC;

forming a lens assembly over the second interconnect layer, the lens assembly comprising first and second lenses respectively aligned with the first and second openings and adhered to the transparent adhesive material; and

forming a plurality of contacts coupled respectively to the plurality of first electrically conductive traces.

2. The method of claim 1, wherein the forming of the IC layer comprises:

forming an adhesive layer over a carrier;

placing the image sensor IC and the light source IC over the adhesive layer; and

forming encapsulation material to laterally surround the image sensor IC and the light source IC, wherein a first major surface of the encapsulation material is directed away from the carrier, and wherein a second major surface of the encapsulation material physically contacts the adhesive layer.

3. The method of claim 2, wherein the forming of the IC layer further comprises:

detaching the IC layer from the carrier after forming the encapsulation material;

flipping the IC layer; and

reattaching the IC layer to the adhesive layer, wherein the first major surface of the encapsulation material physically contacts the adhesive layer after the reattaching.

4. The method of claim 1, wherein the forming of the lens assembly further comprises:

forming a molding compound to surround the first and second lenses; and

forming third and fourth openings respectively aligned with the first and second lenses.

5. The method of claim 1, wherein the plurality of contacts comprises a plurality of ball grid array (BGA) contacts.

6. The method of claim 1, wherein the light source IC comprises a light emitting diode.

7. A method of forming a proximity detector device, the method comprising:

positioning an image sensor integrated circuit (IC) and a light source IC on an adhesive layer of a carrier layer, wherein the image sensor IC and the light source IC are laterally spaced apart;

forming an encapsulation material to surround the image sensor IC and the light source IC to form an IC layer on the carrier layer, wherein a backside of the encapsulation material is directed away from the carrier layer;

flipping the IC layer and placing the IC layer on the carrier layer after forming the encapsulation material;

forming an interconnect layer over the encapsulation material, wherein the interconnect layer comprises electrically conductive traces coupled to contacts of the image sensor IC and contacts of the light source IC, the interconnect layer further comprising first and second openings respectively aligned with the image sensor IC and the light source IC;

forming a transparent adhesive material in the first and second openings;

positioning a first lens and a second lens on the transparent adhesive material, the first lens and the second lens physically contacting the transparent adhesive material and respectively aligned with the image sensor IC and the light source IC;

forming a molding compound over the interconnect layer to surround the first lens and the second lens, wherein the IC layer, the interconnect layer, and the molding compound surrounding the first lens and the second lens form an intermediate structure;

flipping the intermediate structure and placing the intermediate structure on the adhesive layer of the carrier layer, wherein the backside of the encapsulation material is directed away from the carrier layer after flipping the intermediate structure;

removing a portion of the backside of the encapsulation material to expose surfaces of the image sensor IC and the light source IC;

forming a further interconnect layer over the IC layer, the further interconnect layer comprising further electrically conductive traces electrically coupled to the electrically conductive traces of the interconnect layer; and

forming a plurality of contacts coupled to the further electrically conductive traces of the further interconnect layer.

8. The method of claim 7, wherein flipping the IC layer and placing the IC layer on the carrier layer comprises heating the adhesive layer, detaching the IC layer from the adhesive layer, flipping the IC layer, and reattaching the IC layer onto the adhesive layer so that the backside of the encapsulation material is directed toward the carrier layer after flipping the IC layer.

9. The method of claim 7, wherein forming the further interconnect layer over the IC layer comprises forming vias in the IC layer, wherein the vias are electrically coupled to the electrically conductive traces of the interconnect layer, and forming the further electrically conductive traces over the IC layer, wherein the further electrically conductive traces are electrically coupled to the vias in the IC layer.

10. The method of claim 7, further comprising a singulation process to separate the proximity detector device from an adjacently-formed proximity detector device.

11. The method of claim 7, wherein the plurality of contacts comprises a plurality of ball grid array (BGA) contacts.

12. The method of claim 7, wherein removing the portion of the backside of the encapsulation material to expose surfaces of the image sensor IC and the light source IC comprises grinding the backside of the encapsulation material.

13. The method of claim 7, wherein the first lens comprises a filter lens.

14. The method of claim 7, wherein the first lens comprises a focusing element.

15. The method of claim 7, wherein the light source IC comprises a light emitting diode.

16. The method of claim 15, wherein the light emitting diode comprises an infrared light emitting diode.

17. The method of claim 7, wherein forming the transparent adhesive material in the first and second openings comprises filling the first and second openings with the transparent adhesive material, the transparent adhesive material extending out of the first and second openings of the interconnect layer.