▁More ▁recently ▁focused ▁ion ▁beam ▁methods ▁have ▁been ▁used ▁to ▁prepare ▁samples . ▁F IB ▁is ▁a ▁relatively ▁new ▁technique ▁to ▁prepare ▁thin ▁samples ▁for ▁T EM ▁exam ination ▁from ▁larger ▁spec im ens . ▁Because ▁F IB ▁can ▁be ▁used ▁to ▁micro - machine ▁samples ▁very ▁precisely , ▁it ▁is ▁possible ▁to ▁mill ▁very ▁thin ▁memb ran es ▁from ▁a ▁specific ▁area ▁of ▁interest ▁in ▁a ▁sample , ▁such ▁as ▁a ▁sem icon duct or ▁or ▁metal . ▁Un like ▁in ert ▁gas ▁ion ▁s put ter ing , ▁F IB ▁makes ▁use ▁of ▁significantly ▁more ▁ener get ic ▁gal li um ▁ ions ▁and ▁may ▁alter ▁the ▁composition ▁or ▁structure ▁of ▁the ▁material ▁through ▁gal li um ▁impl ant ation . ▁ ▁Rep lication ▁ ▁Sam ples ▁may ▁also ▁be ▁rep licated ▁using ▁cell ul ose ▁ac et ate ▁film , ▁the ▁film ▁subsequently ▁co ated ▁with ▁a ▁heavy ▁metal ▁such ▁as ▁plat in um , ▁the ▁original ▁film ▁dissol ved ▁away , ▁and ▁the ▁rep lica ▁im aged ▁on ▁the ▁T EM . ▁Vari ations ▁of ▁the ▁rep lica ▁technique ▁are ▁used ▁for ▁both ▁materials ▁and ▁bi ological ▁samples . ▁In ▁materials ▁science ▁a ▁common ▁use ▁is ▁for ▁exam ining ▁the ▁fresh ▁f ract ure ▁surface ▁of ▁metal ▁allo ys . ▁ ▁Mod ifications ▁The ▁capabilities ▁of ▁the ▁T EM ▁can ▁be ▁further ▁extended ▁by ▁additional ▁stages ▁and ▁detect ors , ▁sometimes ▁incorpor ated ▁on ▁the ▁same ▁mic ros cope . ▁ ▁Sc anning ▁T EM ▁A ▁T EM ▁can