A method and a system for obtaining an image of a cross section of a specimen, the method includes: milling the specimen so as to expose a cross section of the specimen, in which the cross section comprises at least one first portion made of a first material and at least one second portion made of a second material; smoothing the cross section; performing gas assisted etching of the cross section so as generate a topography difference between the at least one first portion and the at least one second portion of the cross section; coating the cross section with a thin layer of conductive material; and obtaining an image of the cross section; wherein the milling, smoothing, performing, coating and obtaining are performed while the specimen is placed in a vacuum chamber.