Four channels cross correlation method for high sensitivity current noise measurements

We demonstrate how it is possible to increase the sensitivity of current noise measurement systems by exploiting the properties of a differential transconductance amplifier coupled with a four channels measurement system. In particular, it is demonstrated that, in proper conditions and by a proper elaboration of the acquired signals, the noise contribution coming from the active and passive devices that make up the transresistance amplifier can be virtually eliminated. The method is validated by means of actual measurements in order to demonstrate the effectiveness of the approach we propose.