US 12,174,530 B1
Nano-patterning methods including: (1) patterning of nanophotonic structures at optical fiber tip for refractive index sensing and (2) plasmonic crystal incorporating graphene oxide gas sensor for detection of volatile organic compounds
Ratnesh Kumar, Ames, IA (US); Shawana Tabassum, Ames, IA (US); and Liang Dong, Ames, IA (US)
Assigned to Iowa State University Research Foundation, Inc., Ames, IA (US)
Filed by Iowa State University Research Foundation, Inc., Ames, IA (US)
Filed on Jun. 3, 2020, as Appl. No. 16/946,028.
Application 16/946,028 is a division of application No. 15/791,174, filed on Oct. 23, 2017, granted, now 10,725,373.
Claims priority of provisional application 62/411,402, filed on Oct. 21, 2016.
Int. Cl. G03F 7/00 (2006.01); B29C 41/42 (2006.01); G02B 1/02 (2006.01); G02B 1/04 (2006.01); G03F 7/20 (2006.01); H01L 21/027 (2006.01)
CPC G03F 7/0002 (2013.01) [B29C 41/42 (2013.01); G02B 1/02 (2013.01); G02B 1/045 (2013.01); G03F 7/2012 (2013.01); G03F 7/2014 (2013.01); H01L 21/027 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A sensor for sensing for presence of concentrations of molecules of interest in an analyte based on measuring shift in resonant wavelength of incident light from refractive index modulation at the sensor comprising:
a. a sensing element adapted for exposure to an analyte comprising:
i. a cured or hardened array of nano-molded polymeric nanostructures of tunable refractive index by nanopatterning of form factor and periodicity adhered to a substrate, wherein the polymeric nanostructures have a regular periodicity and each have a relatively similar height and diameter;
ii. an overlayer or deposit of optical resonance material over at least a portion of the polymeric nanoscale structures to produce a shift in resonance wavelength of incident light by guided mode resonance (GMR) or by plasmonic response, wherein the optical resonance material is overlaid on at least the tops of the polymeric nanostructures to achieve optical resonances over the nanopattern in the presence of illumination; and
iii. an overlayer or deposit of graphene oxide (GO) or graphene composite material adhered over at least some of the optical resonance material to effectively absorb an analyte to be sensed;
b. an illumination source to illuminate the sensing element, and
c. a detector to receive and compare light from the sensing element to a reference to suggest the presence of the molecules of interest in an absorbed analyte based on measuring resonance shifts related to refractive index changes to the illumination from guided mode resonance or plasmonic response through the array and graphene oxide (GO) or graphene composite material.