Spectroscopy at atomic level by using a scanning tuneling microscope (STM)

Author(s)

Tomás Erikson Lamas

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Física (IF/SBI)
• Defense date: 1999-12-20

Examining board members

Alain Andre Quivy; Mônica Alonso Cotta; Marina Amelia Pinto Viegas da Silveira Santos

• Advisor: Alain Andre Quivy

Abstract

The goal of the present work was to upgrade the home-made Scanning Tunneling Microscope present in our group, adding the new hardware necessary to carry out spectroscopic measurements. A new software was also developed to control the new functions of the microscope. In order to check the performance of the whole system, several types of experiments where carried out on graphite and gold. A special care was taken to adequately prepare the samples of III-V semiconductors. The passivation of the sample yielded the best results both for topographic and spectroscopic measurements. Finally, I-V curves were taken on GaAs layers and InAs quantum dots grown by molecular beam epitaxy (MBE). (AU)