NOBUGS conference11-05-2002

Camera“Scanning Probe Microscope” software for

instrument control and data analysis.

E.H. v. Tol – Homan, G. v. Velzen, R. v. Gastel, M. Seynen*

University Leiden, The Netherlands

*Institute for Atomic and Molecular Physics (AMOLF-FOM), Amsterdam

http://www.physics.leidenuniv.nl/sections/cm/ip/ 11-05-2002

Overview

Overview

Introduction to Scanning Probe Microscopes (SPM) SPM – software specifications (video rate) Instrument control Data analysis SPM – software architecture Conclusion

Scanning Probe Microscopes (SPM)

Scanning Probe Microscopes:

•Scanning Tunneling Microscope (STM)•Atomic Force Microscopes (AFM)•…

Scanning Probe Microscopes (SPM)

Scanning Probe Microscopes:

•Scanning Tunneling Microscope (STM)•Atomic Force Microscopes (AFM)•…

The Scanning Tunneling Microscope works like a record player…

Scanning Probe Microscopes (SPM)

X,YScan circuit

PiezoFeedbackElectronics PC

specimenU sample

Z

Ittip

Scanning Probe Microscopes (SPM)

Line scan image of graphite surface. Each bump corresponds to a single carbon atom. The size of the image is only 3 nm 3 nm.

15 yearsAgo:

Now:

Perspective color view of Graphite surface

“PhotoCamera”

Scanning Probe Microscopes (SPM)

New “Video camera”

High speed scanning probe microscope:

•25 pictures (256 x 256) per second

•Maximum scan speed: 3,3*106 pixels/sec

Scanning Probe Microscopes (SPM)

Au (110)

Usample =-0.7V~ 22000 pixels/sec300 nm x 300 nm

Scanning Probe Microscopes (SPM)

Au (110)

Usample =-0.7V~ 134000 pixels/sec300 nm x 300 nm

SPM – software specifications

Computer specification for a high speed SPM:

Dual processor:first processor: data display / analysis / scalingsecond processor: instrument control

Dual monitor:first monitor data displaysecond monitor instrument control - window

SPM – software specifications

General specifications for a high speed SPM:

1. Two “user modes of operation”:

online and offline mode.

Online Mode-measurement

-analysis

Offline Mode-Post measurement analysis

GUI

SPM – software specifications

Online Mode Offline Mode

GUI

General specifications:

2. The program uses a DLL to configure and drive the hardware of the SPM. (Different DLL’s for each SPM)

STM- DLL …AFM- DLL

SPM – software specifications

Boundary requirements:

Very stable and reliable Fast data handling and graphics Extendable, Users can add own filters Windows look and feel

RECOVERY PROCEDURE !

SPM – software specifications

Why winNT (decided three years ago) ?

Multi tasking operating system Drivers for microEnable / hotlink only available under winNT. Commonly know environment Offline mode can run under windows 98,2002, XP

RT/Time-sharing

Real-time part: dedicated hardware

Time sharing – part: winNT (GUI).

SPM – software specifications

A collection of C++ classes and an application framework for creating Microsoft windows-based applications.

Document / View structure

SPM – software specifications

Document / View structure:

SPM – DATA

Instrument control

GUI

Online Mode-measurement

-analysis

Offline Mode-Post measurement analysis

Instrument control

MAIN SPMDLL

Data display

Instrument control

Instrument control

Measurement mode:

1. Approach (bringing the tip to the surface)

2. Setting scanning parameters

3. Scan (with video rate)

4. Save

During measurement analysis and display through main program.

Data analysis

GUI

Online Mode-measurement

-analysis

Offline Mode-Post measurement analysis

Data analysis

Data analysis

Height line:

Data analysis

3D:

Data analysis

Filter functions:

Clipping: image size adjustFilters:

Differentiate,Background subtraction…

FILTERDLL

MAIN

USER DEFINED DLL

Data analysis

Original data:

Data analysis

Backgroundsubtraction:

Data analysis

Differentiate(line by line)data:

SPM – software architecture

Architecture

Online Module Offline Module

GUI

STM- DLL AFM- DLL

SPM – software architecture

The interface (for Instrument Control) DLL:

MFC DLL, dynamically linked to theMFC-libraries.

Init Instance / Exit instance are called when the DLL is loaded / freed from memory.

SPM – software internally

MAIN DLL

SendSPMCommand

This function is defined in the DLL, and called by the MAIN.

SendNotifyThis function is defined in the MAIN, and called by the DLL.

SPM – software internally

MAIN DLL

SendSPMCommand

This function is defined in the DLL, and called by the MAIN.

Set / GetDeviceConfig

GetDeviceStatus / GetLastError

CommandWindowCreate / Close

…

SPM – software internally

MAIN DLLSendNotify

This function is defined in the MAIN, and called by the DLL.

StartScanMeasurement

UpdateFrameData

StopScanMeasurement

…

SPM – software internally

Threads overview

MEASUREMENTGUI

DISPLAY

Thread Safe

SPM – software internally

DLL

Hardware

Message Loop

Disk

SPM – software internally

Message Loop

MAIN

Process Filters

Conclusion

A graphical user interface for a high speed SPM (with video rate) has been developed using MFC and winNT.

NO BUGS

Interface physics group

The Team:

Prof. Dr. J.W.M. Frenken (Group leader)Dr. ir. T.H. Oosterkamp (Group leader)Dr. M.J. Rost (Post-Doc)Ir. K. Schoots (Ph.D. Student)R. v. Gastel (Ph.D. Student)

Ing. B. Crama (Electronics) *B. Okhuysen (Group leader)Ing. P. Schakel (Electronics) *Ing. M. Seynen (Software)Ing. E.H. v. Tol-Homan (Software) *Ing. H. Dekker (Electronics)Ing. G. v. Velzen (Software) *Ing. A. Vijftigschild (Electronics)

*AMOLF/FOM

Email: vantol@fwneld.leidenuniv.nlWeb page: http://www.physics.leidenuniv.nl/sections/cm/ip/