Experimental Difficulties in Data Acquisition

Reducing the experiment duration is desirable. For example, a 100 x 100 fjum2 image requires 16 minutes to acquire with 1 /xm resolution at a scan rate of 10 gm/s. That may be too long to resolve chemical or electrochemical changes on a substrate surface. Increasing the probe scan rate will decrease the acquisition time, but this may not be feasible. 

Decreasing the tip size can increase image resolution. However, difficulties arise in simultaneously improving resolution, experiment duration, and SNR in the SECM experiment. At least one goal must be compromised to improve the others, and improving image resolution will be most challenging. 

Theoretical IT — L plots for 1 /am (top) and 5 /am (bottom) tips over ng substrate. The ideal curves are illustrated with calculated curves showin t of a 5 Hz low-pass filter on the curve shape as the tip is withdrawn fror ice at a rate of 1 /am/s. 

This is a relaxed requirement compared to I-L data acquisition since the distortion due to tip-size function diminishes the effect of low-pass filtering. 

Improving Image Resolution with Small Diameter Tips 

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