Study of laser-induced graphene based flexible humidity sensor
Open Access
Author:
Yu, Zhaozheng
Graduate Program:
Engineering Science and Mechanics
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
November 12, 2019
Committee Members:
Huanyu Cheng, Thesis Advisor/Co-Advisor Judith Todd Copley, Program Head/Chair Elzbieta Sikora, Committee Member Jian Hsu, Committee Member
Keywords:
LIG Humidity sensor
Abstract:
Capacitive humidity sensors based on laser-induced graphene (LIG) were fabricated by using the CO2 laser to scribe on the commercial polyimide thin film (thickness = 50µm). The laser-ablated region of the polyimide turns into a porous structure with carbon as the main composition. Raman spectra and scanning electron microscope were used to characterize the LIG’s chemical and morphology. Patterning LIG into the interdigitated electrode (IDE) to serve as both the electrode and sensing materials was achieved in one step. The proposed flexible humidity sensor demonstrates the sensitivity of 10% and response/recovery time of 109s/13.5s, respectively. In general, a promising humidity sensor with improved response/recovery time and good sensitivity can be fabricated in an easy, fast, and low-cost manner.
