Optical sensor having a light emitter and a photodetector assembly directly mounted to a transparent substrate

Patent metadata

Field	Value
Publication number	US-9627573-B2
Application number	US-201514625753-A
Country	US
Kind code	B2
Filing date	Feb 19, 2015
Priority date	Feb 21, 2014
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

An optical sensor is described that includes a light emitter and a photodetector assembly directly attached to a transparent substrate. In one or more implementations, the optical sensor comprises at least one light emitter and a photodetector assembly (e.g., photodiodes, phototransistors, etc.). The light emitter(s) and the photodetector assembly are directly mounted (e.g., attached) to a transparent substrate.

First claim

What is claimed is:

1. An optical sensor comprising:
a transparent substrate having a surface;
at least one light emitter directly mounted to the surface of the transparent substrate, the at least one light emitter configured to emit light;
a photodetector assembly directly mounted to the surface of the transparent substrate, the photodetector assembly configured to detect light and provide a signal in response thereto;
a polymeric encapsulation structure disposed over the surface of the transparent substrate that at least substantially encapsulates the at least one light emitter and the photodetector assembly, the polymeric encapsulation structure comprising at least one of scattering elements or absorbing elements, the polymeric encapsulation structure having a surface distal to the surface of the transparent substrate; and
a plurality of solder bumps disposed over the surface of the transparent substrate, respective solder bumps of the plurality of solder bumps extending beyond a plane that is co-planar with the surface of the polymeric encapsulation structure.

2. The optical sensor as recited in claim 1 , wherein the transparent substrate includes at least one redistribution structure disposed thereon, and wherein the at least one light emitter and the photodetector assembly is electrically connected to the at least one redistribution structure.

3. The optical sensor as recited in claim 2 , further comprising an electrical interconnection disposed between the at least one light emitter and the at least one redistribution structure comprises at least one of a gold-gold interconnection, a gold-tin interconnection, a silver-tin interconnection, a copper-tin interconnection or a copper-copper interconnection.

4. The optical sensor as recited in claim 1 , wherein the at least one light emitter is configured to emit light in at least one of the visible light spectrum, the ultraviolet spectrum, or the infrared spectrum.

5. The optical sensor as recited in claim 1 , wherein the at least one light emitter comprises a plurality of light emitters.

6. The optical sensor as recited in claim 1 , wherein the at least one light emitter comprises a light emitting diode.

7. The optical sensor as recited in claim 1 , wherein the at least one light emitter comprises a vertical-cavity surface-emitting laser.

8. The optical sensor as recited in claim 1 , wherein the photodetector assembly includes at least one of photodiodes, photoresistors, or phototransistors.

9. The optical sensor as recited in claim 1 , further comprising a light modifying structure disposed over the transparent substrate configured to modify light.

10. The optical sensor as recited in claim 9 , wherein the light modifying structure comprises at least one of a lens, a diffuser, a scattering element, a diffractive optical element, or a holographic optical element.

11. The optical sensor as recited in claim 1 , further comprising a polymeric layer that at least partially covers one surface of the transparent substrate, wherein the polymeric layer comprises at least one of scattering elements or absorbing elements.

12. The optical sensor as recited in claim 1 , further comprising an anti-reflection coating disposed over the transparent substrate.

13. The optical sensor as recited in claim 1 , wherein the transparent substrate comprises a glass substrate, a sapphire substrate, a diamond substrate, a zinc sulphide substrate, a zinc selenide substrate, a polymer substrate, a germanium substrate, or a silicon substrate.

14. The optical sensor as recited in claim 1 , wherein the transparent substrate has coefficient of thermal expansion approximately matching the coefficient of thermal expansion of silicon.

15. The optical sensor as recited in claim 1 , further comprising integrated circuitry electrically connected to the photodetector assembly, wherein the integrated device circuitry comprises at least one of driver circuitry, analog circuitry, digital circuitry, signal processing circuitry, or signal conversion circuitry.

16. A method comprising:
forming one or more redistribution structures over a transparent substrate;
mounting at least one light emitter to a surface of the transparent substrate, the at least one light emitter configured to emit light;
mounting a photodetector assembly to the surface of the transparent substrate, the photodetector assembly configured to detect light and provide a signal in response thereto;
forming an encapsulation structure over the surface of the transparent substrate, the encapsulation structure at least substantially encapsulates the at least one light emitter and the photodetector assembly, the encapsulation structure comprising at least one of scattering elements or absorbing elements, the encapsulation structure having a surface distal to the surface of the transparent substrate; and
forming a plurality of solder bumps over the surface of the transparent substrate, respective solder bumps of the plurality of solder bumps extending beyond a plane that is co-planar with the surface of the polymeric encapsulation structure.

17. An optical sensor comprising:
a transparent substrate having a surface;
at least one light emitter directly mounted to the surface of the transparent substrate, the at least one light emitter configured to emit light;
a photodetector assembly directly mounted to the surface of the transparent substrate, the photodetector assembly configured to detect light and provide a signal in response thereto;
at least one redistribution structure disposed over the transparent substrate, the at least one light emitter and the photodetector assembly electrically connected to the at least one redistribution structure;
an encapsulation structure disposed over the surface of the transparent substrate that at least substantially encapsulates the at least one light emitter and the photodetector assembly, the encapsulation structure comprising at least one of scattering elements or absorbing elements, the encapsulation structure having a surface distal to the surface of the transparent substrate; and
a plurality of solder bumps disposed over the surface of the transparent substrate, respective solder bumps of the plurality of solder bumps extending beyond a plane that is co-planar with the surface of the encapsulation structure.

18. The optical sensor as recited in claim 17 , further comprising a light modifying structure disposed over the transparent substrate configured to modify light.

Assignees

• Maxim Integrated Products
• Maxim Integreated Products Inc

Inventors

• Bhat Jerome C
• Allen Dan G
• Olsen Richard I
• Nagarajan Kumar

Classifications

• H01L31/167 Primary

  Electricity · mapped topic

• H01L31/147

  Electricity · mapped topic

• H10F55/15

  wherein the radiation-sensitive devices and the electric light source are all semiconductor devices · CPC title

• H10F55/25 Primary

  wherein the radiation-sensitive devices and the electric light source are all semiconductor devices · CPC title