Chemical Analysis of Surface by Fluorescent X-Ray Spectroscopy Using RHEED-SSD Method

Abstract

A new RHEED apparatus combined with a Si(Li) solid-state detector has been constructed, and spectroscopy of fluorescent X-rays emitted during RHEED observation has been carried out using the detector. Preliminary measurements have revealed the usefulness of this apparatus both for chemical analysis of surfaces and for investigating the behaviour of incident electrons in surface layers. When Ag thin films evaporated on a clean Si(111) surface were studied, the smallest detectable amount was about 0.02 Å in mean thickness. The penetration depth of the primary electron beam in the Ag film at an accelerating voltage of 20 kV was estimated to be 33.0 Å from analysis of the intensity of AgLα and AgLβ lines with increasing thickness of the Ag films.