Professor van Helvoort introduces in his presentation the interest of using III-V semiconducting nanowires in future optoelectronic devices. He highlights the need to characterize the electronic properties of such nanowires in order optimize them for these applications and summarizes the challenges his group encountered in pursuing that objective.
He then explains the methodology they followed to deposit metal using e-beam (EBID) to contact the nanowires. He describes the probing set-up they have built to connect a source/meter unit (SMU) (Keithley Instruments model 2636A) with Imina Technologies nanoprobers inside the vacuum chamber of their electron microscope (FEI Helios NanoLab 600). He shows the advantage of the 4-point vs the 2-point probe measurement technique to get rid of the contact resistance when carrying out I-V measurements. Prof. van Helvoort ends his presentation by giving some examples of measurements and discusses some strategies for improvements and future experiments.
This presentation has been held by Prof. Ton van Helvoort at NTNU Throndheim, Norway during the Imina Technologies’ webinar session that took place on September 24, 2014. The work described in this presentation is done at NTNU NanoLab and within the Nanowire Project led by Prof. Bjørn-Ove Fimland and Prof. Helge Weman at the Department of Electronics and Telecommunication.