Integrated detection device, in particular detector particles such as particulates or alpha particles

Patent metadata

Field	Value
Publication number	US-10962659-B2
Application number	US-201816174016-A
Country	US
Kind code	B2
Filing date	Oct 29, 2018
Priority date	Sep 17, 2014
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

A process for manufacturing an optical system includes forming a first hydrophobic surface at a semiconductor substrate, providing a first drop of transparent material having a first shape on the first hydrophobic surface, and allowing the first drop to harden to form a first optical element having the first shape. The optical system may be a particle detector, and the process may optionally further include forming a light source at the semiconductor substrate configured to generate a light beam that passes through the first optical element and a cavity to a photodetector.

First claim

What is claimed is:

1. A process for manufacturing an optical system comprising:
forming a first hydrophobic surface at a semiconductor substrate;
providing a first drop of transparent material having a first shape on the first hydrophobic surface;
allowing the first drop to harden to form a first optical element having the first shape; and
forming a light source at the semiconductor substrate, the light source being configured to generate a light beam;
forming a second hydrophobic surface at the semiconductor substrate;
providing a second drop of transparent material having a second shape on the second hydrophobic surface; and
allowing the second drop to harden to form a second optical element having the second shape, wherein the second optical element is disposed along a path of the light beam, and wherein the first optical element is along the path of the light beam between the light source and the second optical element.

2. The process according to claim 1 , wherein the first hydrophobic surface has a lower surface roughness than the second hydrophobic surface.

3. The process according to claim 1 , wherein a first index of refraction of the first optical element is greater than a second index of refraction of the second optical element.

4. The process according to claim 1 , wherein a first diameter of the first optical element is less than a second diameter of the second optical element.

5. The process according to claim 1 , wherein the first hydrophobic surface is a superhydrophobic surface, and wherein the first shape of the first optical element is substantially spherical.

6. The process according to claim 1 , further comprising:
wherein the path of the light beam passes through the first optical element;
forming a photodetector at the semiconductor substrate along the path of the light beam; and
forming a cavity at the semiconductor substrate along the path of the light beam between the light source and the photodetector, wherein the optical system is a particle detector.

7. The process according to claim 1 , wherein forming the first hydrophobic surface comprises treating the first hydrophobic surface to render the first hydrophobic surface rough.

8. A process for manufacturing an optical system comprising:
treating a first surface of a semiconductor substrate to form a first hydrophobic surface;
providing a first drop of transparent material having a first shape on the first hydrophobic surface;
allowing the first drop to harden to form a first hardened drop having the first shape; and
forming a sacrificial material over the semiconductor substrate;
patterning the sacrificial material;
removing a region of the sacrificial material; and
removing a first portion of the first hardened drop to form a first optical element.

9. The process according to claim 8 , wherein the first optical element is a plano-convex lens.

10. The process according to claim 9 , wherein:
the first hydrophobic surface is a superhydrophobic surface;
the first shape is substantially spherical; and
the first optical element is an extended hemispherical lens.

11. The process according to claim 8 , further comprising:
providing a second drop of transparent material having a second shape on a second hydrophobic surface;
allowing the second drop to harden to form a second hardened drop having the second shape; and
removing a second portion of the second hardened drop while removing the first portion of the first hardened drop to form a second optical element.

12. The process according to claim 11 , wherein:
the both the first optical element and the second optical element are plano-convex lenses; and
a first substantially planar surface of the first optical element faces a second substantially planar surface of the second optical element.

13. The process according to claim 8 , further comprising:
forming a light source at the semiconductor substrate, the light source being configured to generate a light beam, wherein a path of the light beam passes through the first optical element;
forming a photodetector at the semiconductor substrate along the path of the light beam; and
forming a cavity at the semiconductor substrate along the path of the light beam between the light source and the photodetector, wherein the optical system is a particle detector.

14. The process according to claim 8 , wherein treating the first surface comprises roughening the first surface to form the first hydrophobic surface.

15. A process for manufacturing an optical system comprising:
forming an insulating layer on a semiconductor substrate;
forming a first electrode region on the insulating layer;
forming a variable-hydrophobicity layer over the first electrode region, the variable-hydrophobicity layer comprising a top surface and an opposite bottom surface facing the first electrode region;
providing a first drop of transparent material on the top surface of the variable-hydrophobicity layer, the first drop being vertically aligned with the first electrode region, wherein an instant shape of the first drop is a first initial shape;
applying a first bias voltage to the first electrode region to change the instant shape of the first drop from the first initial shape to a first subsequent shape different from the first initial shape; and
allowing the first drop to harden while the instant shape of the first drop is the first subsequent shape to form a first optical element.

16. The process according to claim 15 , wherein the first bias voltage is 25 V or 120 V.

17. The process according to claim 15 , wherein:
the first initial shape of the first drop of transparent material is non-spherical; and
the first subsequent shape of the first drop of transparent material is substantially spherical.

18. The process according to claim 15 , further comprising:
forming a second electrode region on the insulating layer;
providing a second drop of transparent material on the top surface of the variable-hydrophobicity layer, the second drop being vertically aligned with the second electrode region, wherein an instant shape of the second drop is a second initial shape;
changing the instant shape of the second drop from the second initial shape to a second subsequent shape different than the second initial shape; and
allowing the second drop to harden while the instant shape of the second drop is the second subsequent shape to form a second optical element.

19. The process according to claim 18 , further comprising:
forming a dielectric layer disposed between the first electrode region and the second electrode region, wherein the first electrode region is electrically insulated from the second electrode region by the dielectric layer; and
applying a second bias voltage to the second electrode region, the second bias voltage being different from the first bias voltage, wherein the second subsequent shape is different than the first subsequent shape.

20. The process according to claim 15 , further comprising:
forming a light source at the semiconductor substrate, the light source being configured to generate a light beam, wherein a path of the light beam passes through the first optical element;
forming a photodetector at the semiconductor substrate along the path of the light beam; and
forming a cavity at the semiconductor substrate along the path of the light beam between the light source and the photodetector, wherein the optical system is a particle detector.

Assignees

• St Microelectronics Srl

Inventors

• Loi Sara
• Pagani Alberto

Classifications

• G01N15/02 Primary

  Investigating particle size or size distribution (by measuring osmotic pressure G01N7/10; investigating sedimentation of particle suspensions G01N15/04; investigating individual particles G01N15/10) · CPC title

• F04B37/00

  Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 · CPC title

• G01N2015/035

  the optical arrangement forming an integrated apparatus with the sample container · CPC title

• G01T1/244

  Auxiliary details, e.g. casings, cooling, damping or insulation against damage by, e.g. heat, pressure or the like · CPC title

• G01T1/2928

  using solid state detectors · CPC title