Integrated microchip chemical sensor
First Claim
1. A microchip chemical sensor structure for sensing the presence of a substance in an environment comprising:
- (a) a semiconductor base;
(b) a source on said base for emitting a light signal;
(c) at least one light detector integrated into the top surface of said base;
(d) one or more waveguides between said source and said light detector to couple at least some of the light from said source to said light detectors; and
(e) a cladding layer comprising a chemical sensitive material disposed on top of at least one of said waveguides such that the index of refraction for a waveguide having said cladding layer of chemical sensitive material will be a function of the concentration of a target chemical in said environment adjacent to said chemical sensitive material.
1 Assignment
0 Petitions
Accused Products
Abstract
An optical device for sensing properties in an environment such as the presence of a substance or chemical in the zone to be monitored using optical components integrated on a microchip base or substrate. A preferred embodiment introduces a method for fabricating a miniature microchip chemical sensor by integrating a GaAs LED 14 with a polyimide waveguide 48 and a silicon photosensor 16 on the same chip. Light 18 is emitted at the edge of the GaAs LED 14. A portion of the light propagates is detected by a PIN diode 16. A chemical sensitive material 50 is coated on top of a polyimide waveguide 48. When the gas or chemical to which the material is sensitive appears, the light transmitted from the polyimide to air increases, thus the total signal sensed by the photodetector decreases, whereby the change in light signal indicates detection.
59 Citations
24 Claims
-
1. A microchip chemical sensor structure for sensing the presence of a substance in an environment comprising:
-
(a) a semiconductor base; (b) a source on said base for emitting a light signal; (c) at least one light detector integrated into the top surface of said base; (d) one or more waveguides between said source and said light detector to couple at least some of the light from said source to said light detectors; and (e) a cladding layer comprising a chemical sensitive material disposed on top of at least one of said waveguides such that the index of refraction for a waveguide having said cladding layer of chemical sensitive material will be a function of the concentration of a target chemical in said environment adjacent to said chemical sensitive material. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. An integrated microchip chemical sensor structure for sensing the presence of a substance in an environment comprising:
-
(a) a semiconductor substrate; (b) an LED structure disposed on the lateral surface of said semiconductor substrate for emitting a light signal; (c) one or more light detectors disposed in said semiconductor substrate; (d) one or more waveguides between said LED structure and said light detectors to couple at least some of the light from said LED structure to said light detectors wherein at least one of said waveguides is a layer of polyimide applied over said detector; and (e) a cladding layer comprising a chemical sensitive material disposed on each of said waveguides, such that the index of refraction for a waveguide having said cladding layer of chemical sensitive material will be a function of the concentration of a target chemical in said environment adjacent to said chemical sensitive material. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. An integrated microchip chemical sensor structure for sensing the presence of a substance in an environment comprising:
-
(a) a semiconductor substrate; (b) an LED structure disposed on the lateral surface of said semiconductor substrate for emitting a light signal; (c) one or more light detectors integrated into the surface of said semiconductor substrate; (d) one or more waveguides between said LED structure and said light detectors to couple at least some of the light from said LED structure to said light detectors wherein at least one of said waveguides is a layer of polyimide applied over said detector; (e) a cladding layer comprising a chemical sensitive material disposed on each of said waveguides, such that the index of refraction for a waveguide having said cladding layer of chemical sensitive material will be a function of the concentration of a target chemical in said environment adjacent to said chemical sensitive material; and (f) a microprocessor to process the sensor output integrated on said substrate. - View Dependent Claims (21, 22, 23, 24)
-
Specification