Studying micro-objects with SEM (Scanning electron microscope) Student: Michał Łępicki (Warsaw University of Technology) Supervisor: Oleg Leonidovich Orelovich Center of Applied Physics of Flerov Laboratory of Nuclear Reactions JINR

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Program of practices Layout and performance of SEM Layout and performance of SEM Preparing and coating samples Preparing and coating samples Operating SEM Operating SEM Electron data processing Electron data processing

Layout and performance of SEM 1-3Electron gun 4, 10Aperture 5-6Condenser lenses 7Scanning coils 8Stigmator 9Objective lens 11X-ray detector 12Pre-amplifier 13Scanning circuits 14Specimen 15Secondary electron detector 16-18Display/Control circuits

Layout and performance of SEM

Preparing and coating samples General view of ion sputter

Preparing and coating samples

Reasons of coating specimens The surface of sample must be electro conductive to minimalize charging from beam The surface of sample must be electro conductive to minimalize charging from beam The surface must be thermo conductive to minimalize local heating The surface must be thermo conductive to minimalize local heating The material of sample must have a high atomic number to increase secondary electron emission The material of sample must have a high atomic number to increase secondary electron emission

Preparing and coating samples

Gold coated sampleSample without coating

Operating SEM

Preparing and coating samples Tilt 0 deg – shadowless illumination Tilt 30 deg

Operating SEM Tilt 0 deg Tilt 30 deg TILT

Electron data processing A/D

Electron data processing N=1,75*10^7 [channels/cm^2]R=0,5μm average channel radius 13,8% surface cross section (SCS) SCS= Pi*R^2*N*100%

Drain water 70ml filtrated

Puddle water 50ml filtrated

Me operating SEM