淀积气压对脉冲激光淀积La掺杂钛酸铅薄膜介电性能的影响

The effect of oxygen pressure on the dielectric properties of pulsed laser deposited La-doped PbTiO_3 thin film

利用脉冲激光淀积法在Pt Ti SiO2 Si衬底上制备了 2 8mol%La掺杂钛酸铅薄膜 .采用不同的淀积氧气压 ,并分析了其对薄膜微观结构和介电性能的影响 .结果表明 ,在 2Pa左右的气压下淀积的薄膜具有好的结晶度和介电系数 .在频率为 10kHz时 2 8mol%La掺杂钛酸铅薄膜的介电系数达 85 2 ,并且保持了较低的损耗 .同时制备了其他La掺杂浓度的PbTiO3薄膜 ,发现它们也有类似的特点 .

Pb 0 72 La 0 28 TiO 3(PLT28) thin films have been prepared on Pt/Ti/SiO 2/Si substrates by pulsed laser deposition under various oxygen pressure. Experimental study indicated that the oxygen pressure exerts a strong impact on the microstructure and the dielectric properties of the thin films. The film deposited under an oxygen pressure of 2?Pa had a larger dielectric constant and kept a low dielectric loss. At 10?kHz frequency,the dielectric constant was approximately 852 and the dielectric loss was 0 0110 Meanwhile,we found that other La-modified PbTiO 3 films have the same relation between dielectric constant and pressure as the above. Possible explanation is given for this.