Abstract
Visible light probing (VLP) introduced significant spatial resolution improvement by decreasing the wavelength beyond 1064nm. VLP requires thinning the device backside below 10micrometer. Once this challenge is addressed, questions arise regarding invasiveness: how does the laser affect the transistor performance, and how is this manifest in LVx (laser voltage imaging and laser voltage probing) measurements. This paper addresses these questions using a 785nm VLP system. The results are compared with those of 1320nm, 1154nm, and 1064nm when pertinent. It is concluded that changing wavelengths from the traditional 1320nm LVx laser to the visible 785nm laser provides a 40% resolution improvement. Fortunately, decreasing the incident 785nm power eliminates obvious signs of charge-carrier effects. Furthermore, the rise-time is not affected by the laser when measured from the gate.
