Keithley 2648 Counting Electrons1 free download

File name 2648 Counting Electrons1.pdf

A G R E AT E R M E A S U R E O F C O N F I D E N C E toamp range requires a device that can meas- ure currents with a few tens of attoamps RMS noise in the range of 0.1 to 0.01Hz and, in the case of a demonstration setup, a cur- rent source with a resolution better than one attoamp. A category of instruments known in the industry as Source-Measure Units (SMUs) contain a precision voltage source, a precision current source, a voltmeter, and an ammeter. The Keithley Model 6430 Sub- femtoamp Remote SourceMeter instrument Counting Electrons: has an ultra-low noise current amplifier and provides these functions in a single instru- ment. Figure 1 shows a typical SourceMeter How to measure instrument with the source block represent- ing both the voltage source and current source capability. The Vmeasure circle repre- currents in the sents the built-in voltmeter which gives feed- back to the source block and can be used to attoampere range