CONVERSION OF INSULATING THIN-FILMS OF MGIN2O4 INTO TRANSPARENT CONDUCTORS BY ION-IMPLANTATION

MgIn2O4 (IMO) is a crystal with spinel-type structure and has a wide b and gap of similar to 3.5 eV. Electrical conductivities in rf sputter- deposited thin films of IMO at room temperature increased from <10(-7) to similar to 10 S . cm(-1) (n-type conduction) in the as-implanted s tate, when implanted with H+ or Li+ to a fluence of 2x10(16) cm(-2). T he efficiency of carrier generation was similar to 20% in the as-impla nted state and similar to 40% after annealing at 300 degrees C for Hand Li+, respectively. No carrier generation was perceived in He+-impl anted specimens. Although color centers, giving a band at similar to 5 00 nm, were produced by implantation, they disappeared during annealin g at similar to 300 degrees C. As a consequence, optically transparent conducting IMO films were obtained by implantation and subsequent ann ealing.