Efficient analysis of electromagnetic scattering by electrically large objects in a stratified medium has many applications, and one such application is vectorial imaging and detection of defects in integrated circuits and micro and nano devices. For this application, one not only has to solve Maxwell's equations to find the nearfield distribution, but also has to calculate the far-field over a large number of observation angles to form high-resolution images. The most commonly employed method for such an analysis is the moment method in conjunction with a multilayer Green's function, which takes into account the effect of the stratified medium. However, the efficient evaluation of the multilayer Green's function is quite challenging, to say the least, and the application of the moment method to electrically large objects is very computationally intensive. Even after the currents are computed on the objects, calculating the far field over a large number of observation points is nontrivial and can be very time consuming as well.