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Abstract: Lanthanum hexaboride (LaB6) films have been deposited on a zirconium foil by pulsed laser deposition method. The field emission studies of the LaB6 deposited film have been performed in the planar diode configuration under ultra high vacuum conditions. The Fowler–Nordheim plots were found to be linear in accordance with the quantum mechanical tunneling phenomenon. A typical field emission current of 7.02μA was drawn at an applied electric field of 2V/μm. The field enhancement factor is calculated to be 8913cm−1, indicating that the field emission is from nanoscale protrusions present on the emitter surface. The atomic force microscope (AFM) investigation of the surface clearly shows the conical shaped nanoprotrusions of few hundred nanometers with asperities of 20–40nm on its top. The emission current–time plot recorded at the pre-set value of emission current of 5μA over a period of more than 3h exhibits an initial increase and subsequent stabilization of the current. The results reveal that the LaB6/Zr field emitter obtained by the pulsed laser deposition (PLD) is a promising cathode material for practical applications in field emission-based devices. [Copyright &y& Elsevier]

Titanium dioxide (TiO2)-based gate insulators for MOSFETs are of current interest in VLSI technology due to the high permittivity (k) of TiO2. In this paper, we present a study of metal–TiO2–SiO2–Si (MTOS) capacitors with equivalent dielectric thickness (EDT) in the range of 36–130 A˚. Pulsed laser deposition (PLD) of TiO2 to realize this stacked dielectric is being reported for the first time. Interestingly, it has been observed that even though an additional TiO2 layer has been deposited, the capacitance of the MTOS structure actually increases or remains almost the same compared to the MOS device having the same SiO2 layer thickness. Secondary ion mass spectrometric (SIMS) analysis reveals that there is substantial penetration of titanium into the underlying SiO2 layer resulting in a reduction of EDT. In addition, the leakage current of the MTOS capacitor reduced by almost two orders of magnitude and the breakdown field strength nearly doubled after incorporating the TiO2 layer. Thus, PLD is shown to be a viable technique for controlled deposition of TiO2 to achieve lower EDT with smaller leakage current, the two most desirable parameters in present-day MOS devices. [Copyright &y& Elsevier]