The accuracy of measurements is determined by the spatial resolution of the probe to the surface being measured. A motorized drive is controlled with a computer to auto-scan and provide accurate sensor position information with sub-micron resolution.
These measurement systems are designed to be used with IBM type PC computers and compatibles. The computer should have the WINDOWS 7 Pro or later operating system installed. Applicable Electronics provides a computer with any system orders to avoid various problems with PC architectural layouts and software conflicts. We pre-load and test each PC with peripherals and driver software and ASET-LV4 to control the scanning micro sensor techniques.
The ASET LV-4 software is written for the WINDOWS environment in LABVIEW (National Instruments Corp.). The software controls system 3D-motion control, data acquisition and storage, video display and storage and microscope focusing. Routines are also written for auto scanning of samples.
The USB digital camera (at least 1.2 Megapixel) captures and stores images in a number of image formats. The ASET-LV4 software provides for vector data and graphic overlays on video images.
A good microscope is vital for proper spatial resolution. An upright type is very versatile and can be used for most work. Applicable Electronics sells a motorized video zoom scope, VZS-1, designed for corrosion studies. It is an upright type of microscope with zoom adjustment from 10X up to 70X magnification. Other lenses are available for special needs. The system can also be used with an inverted microscope. A side view camera can also be added for more detail.
The best way to calibrate the SVET electrode is to use a point source of current. This requires accurate source placement. You will need an additional 3D positioner (mechanical). SVET wire electrodes can be used as point sources of current, but glass microelectrodes are best.
An oscilloscope is necessary to monitor the probe signal. This will help enormously if trouble arises. One is provided with the system.
A vibration isolation table is best. Applicable Electronics sells TMC Corp. tables with a 3.0’x 3.5’ (30" tall) work surface. It works with compressed air or a nitrogen tank. It has a drilled and tapped (M6) surface hole pattern for mounting things.
A Faraday cage around your experimental area is desirable. It is not necessary for SVET work. For SIET work, it is necessary. Faraday cages made for the air tables are also available.
The data files are in text format for easy transport into commercial spreadsheets and plotting programs. Video images can be recorded in a number of common digital image formats.
You will also need at least 3" of 99.99% Platinum wire for SVET and a dri-ref electrode for SIET/SPET work. Lab-made electrodes can also be used with the system.
You need mechanical parts such as posts and post-holders, glass electrode AgAgCl pellet holders, sample holding platform, small optical rails for mounting things, spare connector pins for the probes and wires. Machining of custom parts is also available by contacting Science Wares.
You will need 10 ml of Hydrogen Hexachloroplatinate 8 wt% solution and 1% Lead (II) acetate for plating electrodes while doing SVET.
The SIET utilizes LIX (liquid ion exchangers) available from Sigma-Fluka. Glass microelectrodes must be silanized with a liquid silane, also from Sigma.