Crystalline thin films of polytetrafluoroethylene were deposited on Si (100) wafers by F2 laser (157 nm) ablation. X-ray photoemission spectra indicated that the composition of deposited films was similar to the source material. The surface morphology of films deposited at room temperature contained numerous fibrous structures in size of 100N40o nm, but they were smoothed out at elevated wafer temperature of N370 K. The refractive index was N1.35 at 633 nm. Ionized fragments in the ablation plume were measured by a Faraday cup assembly, but their effect on the deposited films was not observed at the present ionization ratio.

No abstract

No abstract

No abstract

Imaging of defect density distributions in GaN was carried out. We measured transient absorption of the deep impurity levels by a 400 nm probe pulse followed by three-photon carrier pumping with an 800 nm pump pulse.