Senior Theses

Publication Date


Document Type

Thesis (Open Access)

Degree Name

Bachelor of Science in Physics



Faculty Advisor(s)

Michael Crosser (Thesis Advisor)
William Mackie & Keron Subero (Committee Members)

Subject Categories

Biological and Chemical Physics | Condensed Matter Physics | Physics


The use of graphene field-effect transistors as a biosensor is increasingly being used to study biological phenomena, due to the sensitivity and low reactivity of graphene. To further improve sensitivity in biological environments, we examined how different salt concentrations affect the mobility of capacitance of the graphene. Samples were also measured after an annealing process. We report on the positive correlation between sensitivity and electrolyte concentration and speculate on methods to improve future detectors. Mobility of the device was found to change from 1.07*103cm2/ (V*s) in de-ionized water to 2.78*103cm2/ (V*s) in a 500 mM potassium phosphate buffer solution.