Nanotechnology - Nanotech Labs

Lab N1: AFM - functionning, artefacs and image treatments The first part of this lab is based on simulators for the functioning of the AFM and it represents the introduction for the future labs (N2 and N3) and for the AFM lecture.   In the second part of the lab, the image treatments will be discussed. How do you obtain from a rough measurement data (which can look like the figure below, on the left), the real image of the surface (which is on the right)? Lab N2: AFM - contact mode

This practical is focused on the atomic force microscope (AFM) in contact mode. It is divided into two parts: the first concerning the AFM as a topography measurement tool and the second presenting an application of the AFM for nano-fabrication. The objectives of this practical are: to understand how an AFM works in contact mode, to learn how to use it in order to obtain correct images, to analyze the images obtained and to use it as a nano-fabrication tool. The figure below shows a typical image of the gate of one of the transistors that are fabricated in the clean-room, during the technology lab sessions.

Lab N3: AFM - tapping mode This practical is focused on the atomic force microscope (AFM) in intermittent contact mode (also called, Tapping ModeTM). It is divided into two parts: the first, concerning the AFM as a topography measurement tool and the second presenting an application of the AFM for electrical measurements (electric force microscopy, EFM). In the topography mode, the objectives are: understanding the functioning of the Atomic Force Microscopy (AFM) in intermittent contact mode, learning how to use it and analyzing the images obtained. Nanometric objects will be scanned and the AFM given measurements of height and width are to be analyzed with respect to the tip convolution with the surface. In the electrical mode (EFM), the objective is to charge a silicon oxide layer by the polarized tip and to detect the charging effects in lift mode. A typical example obtained by students is shown in the image below. Two charging voltages (one positive and one negative) were tested and the phase in the lift mode (image on the right) allows distinguishing the two charging spots.

Lab N4: STM This practical is dedicated to the study of the Scanning Tunneling Microscope (STM) through two complementary approaches: simulation (using Nanonis) and practical (using the Nanosurf STM). A special attention is given to the interpretation of obtained data (images and spectroscopy curves).   The image below was obtained by students and it clearly shows atomic resolution obtained during the practical on graphite surface.