an introduction to sims and the minisims tof © millbrook instruments limited blackburn, uk

An Introduction

to SIMS and

the MiniSIMS ToF

© Millbrook Instruments Limited Blackburn, UK

www.millbrook-instruments.com

www.minisims.com

Secondary Ion Mass Spectrometry (SIMS)

&

The Millbrook MiniSIMS

The SIMS Process

simulation courtesy of Dr Postawa Zbigniew

at the Jagiellonian University in Poland

A Conventional SIMS System

The MiniSIMS Instrument

Design Objectives

• Increase routine use of Surface Analysis

– more affordable– more accessible

• Not a replacement for conventional SIMS

– not state-of-the-art performance– restricted analysis conditions

Transform one of these …..

….. into one of these.

Operational Strengths

• Low Capital & Running Costs

• Fast, On-Site Analysis

• Compact Design, Single Electrical Supply

• Full Automation & Control for Ease of Use

• High Reliability

• Rapid Sample Throughput

• Simplified Data Interpretation

• Remote Control via Internet

Typical Application Areas

• Surface Coatings

• Surface Treatments

• Electronic Components

• Semiconductors

• Electrodes & Sensors

• Catalysts

• Adhesives

• Lubricants

• Packaging Materials

• Corrosion Studies

Alternatives to a MiniSIMS ?

• No Other Benchtop SIMS Instrument

• Conventional SIMS Systems

– much more complex and expensive

• Contract Analysis Laboratories

– not convenient, contamination during transport

• Other Surface Analysis Techniques

– generally less sensitive

Comparison of

SEM / EDS and SIMS

Advantages of SEM / EDS

• High magnification physical image

• Quantitative elemental information

Advantages of SIMS

• Surface specific analysis

• Organic structure identification

• Profiling for depth distribution

• Light element detection

EDX sampling depth is typically 1 micron

For many applications surface sensitivity is needed…

Not 10 xNot 100 xBut 1000 x – SIMS can offer true surface analysis

509 m

Conclusions

• SIMS & EDS give complementary information

• SIMS has advantages for

– Organic surface contamination– 3 dimensional analysis of multi-layer structures

• SEM / EDS has advantages for

– High magnification physical imaging– Quantitative analysis

MiniSIMS ToF

Typical Applications for the MiniSIMS ToF

• Analysis of unknown samples (failure analysis)

• Analysis of unique samples

• Improved analysis of organic materials

• Smaller area static SIMS analysis

• Retrospective experiments

MiniSIMS ToF

• Advantages over Quadrupole Instrument

– Smaller area static SIMS analysis

– Extended mass range

– Higher mass resolution (organic v inorganic)

– Retrospective experiments

MiniSIMS ToF

• Use of Continuous Primary Beam

– Fast analysis (= low cost per sample)

– No loss of image resolution in pulsing

– Simplified depth profiling (single beam)

• Fast & simple static / imaging / dynamic

SIMS in one instrument

Static SIMS (Surface Analysis)

Polycarbonate (Bisphenol–A)

Characterisation of Layer

Structurally significant peaks

Characterisation of Layer

Structurally significant peaks

Effect of Decreasing Area

Analysis Area

Dimension

Mass Scale

Quadrupole Data

Effect of Decreasing Area

Analysis Area

Dimension

Mass Scale

Time of Flight Data

Higher Mass Resolution

Higher Mass Resolution

High Mass Peaks (KI)

0

100

200

300

400

350 550 750 950 1150 1350

Mass

Inte

nsi

ty

Extended Mass Range

K9I8

Extended Mass Range

ToF –ve ion mode: Irganox molecular ion at m/z = 1175 Da

Imaging SIMS (Spatial Analysis)

Surface Organic Contaminant Analysis

Retrospective Analysis

Retrospective Analysis

Retrospective Analysis

Dynamic SIMS (Depth Analysis)

Multi-Layer Coating

(Three Dimensional Analysis)

Retrospective Profiling

Conventional Profile

Sodium high at surface

Retrospective Cross-Section

Sodium inclusion in layer

Sodium high at surface

Retrospective Profiling

Retrospective Analysis

Horizontal Image of inclusion

Summary

MiniSIMS Summary

• SIMS is a powerful technique for the 3-D analysis of the surfaces of materials and thin films

• Information easily available by SIMS may be difficult or impossible by any other technique

• SIMS is especially valuable for the detection of:-– organic species (e.g. silicones, fluorocarbons)

– light elements (lithium, beryllium, boron …)

– group IA & IIA metals, group VII halides

MiniSIMS Summary

• SIMS is a fast analysis technique, especially for imaging applications

• MiniSIMS ToF is most effective for a comparative analysis of samples

• Desktop MiniSIMS means SIMS is now affordable and accessible to all

ToF MiniSIMS( v conventional ToFSIMS )

• Use of Continuous Primary Beam– Fast analysis (= low cost per sample)

– No loss of image resolution in pulsing

– Simplified depth profiling (single beam)

• Fast & simple static / imaging / dynamic

SIMS in one instrument

• Upgrade path from Quadrupole to TOF

ToF MiniSIMS( v quadrupole MiniSIMS )

• Improved Static SIMS from smaller areas• Retrospective Experiment

– 2D Imaging– 3D Imaging / Depth Profiling

• Extended Mass Range• Higher Mass Resolution