| Popis: |
For realization of next-generation embedded capacitors in high-density printed circuit boards, a high capacitance density and a low loss of capacitor lms are needed. To make reliable capacitors, we performed a systematic investigation of the dielectric and the ferroelectric properties of (Pb,La)(Zr,Ti)O3 (PLZT) lms with a LaNiO3 (LNO) bu er layer deposited by a chemical solution deposition method for the rhombohedral (La/Zr/Ti = 7/62/38) composition. The lms with a LNO bu er layer on Ni-plated Cu foils showed a very dense and uniform microstructure. The PLZT lms were found to a reduced hysteretic behavior, unlike general ferroelectric PZT lms. The addition of a high concentration of a La dopant, such as 7 mol%, led to almost no or negligible hysteresis and a low coercive voltage, implying that PLZT with a high concentration of La dopant is a good candidate material for embedded capacitor applications. The capacitance values measured in this experiment were approximately 8 times higher than those of undoped PZT on conventional Ni-plated Cu foils. The capacitance density of the lms was approximately 2.4 F/cm2 and the loss tangent was below 1 %. The results show that PLZT lms with an appropriate bu er layer, such as LNO, are strong candidates for high-performance embedded capacitors, providing a possibility of realizing next-generation embedded capacitors with ultra-high capacitance in printed circuit boards. |
