High Performance of Metallic Thin Films for Resistance Temperature Devices with Antimicrobial Properties

Titanium-copper alloy films with stoichiometry given by Ti1-xCux were produced by magnetron co-sputtering technique and analyzed in order to explore the suitability of the films to be applied as resistive temperature sensors with antimicrobial properties. For that, the copper (Cu) amount in the films was varied by applying different DC currents to the source during the deposition in order to change the Cu concentration. As a result, the samples showed excellent thermoresistivity linearity and stability for temperatures in the range between room temperature to 110 degrees C. The sample concentration of Ti0.70Cu0.30 has better characteristics to act as RTD, especially the alpha(TCR) of 1990 x10(-6)degrees C-1. The antimicrobial properties of the Ti1-xCux films were analyzed by exposing the films to the bacterias S. aureus and E. coli, and comparing them with bare Ti and Cu films that underwent the same protocol. The Ti1-xCux thin films showed bactericidal effects, by log(10) reduction for both bacteria, irrespective of the Cu concentrations. As a test of concept, the selected sample was subjected to 160 h reacting to variations in ambient temperature, presenting results similar to a commercial temperature sensor. Therefore, these Ti1-xCux thin films become excellent antimicrobial candidates to act as temperature sensors in advanced coating systems.

Automated summary

Titanium-copper alloy films with different copper concentrations were produced using magnetron sputtering and showed excellent thermoresistivity linearity and stability. The Ti0.70Cu0.30 sample exhibited the best characteristics as a temperature sensor. The Ti1-xCux films also demonstrated antibacterial properties.