Influence of deposition temperature on ionic conductivity of perovskite (Li0.5 La0.5) TiO3 solid state electrolyte thin film

Thin film microbattery is a promising micropower source for its high energy density and good cell performances, and the application of fast lithium ion conducting solids as electrolytes is thus very important. (Li0.5 La0.5 )TiO3 (LLTO) thin film electrolytes for thin film microbattery were prepared onto Pt/Si substrates using magnetron sputtering. As-deposited LLTO thin films showed amorphous-like phases and when deposition temperature increases the ionic conductivity raises accordingly. The ionic conductivity of LLTO thin film reaches 8. 7 × 10-6 S/cm when the deposition temperature is 400℃, which shows that the LLTO thin films deposited by magnetron sputtering are suitable for application as an electrolyte for thin film microbattery.     

应用Monte Carlo方法对GaN基微型核电池的研究

应用Monte Carlo方法,建立了电子入射到半导体材料中的路径模型.基于此模型进行仿真,可以得到电子在半导体材料中的穿透深度和能量分布.对以同位素Ni-63为放射源的GaN基PN结微型核电池进行Monte Carlo分析,得出入射电子在GaN中的穿透路径和能量分布,以确定入射电子在GaN中能量最集中的位置,将GaN基PN结的结深设置在该位置可以大幅提高收集效率,进而提高输出功率与能量转换效率.实验中,分别制备了结深为1000,450 nm,放射源为Ni-63的GaN基微型核电池,测试结果验证了经优化结深为450 nm的微型核电池其电学输出性能有明显提高,能量转换效率达到了1.47％,输出功率达到了微瓦级.该结果可以为GaN基微型核电池的设计与制造提供有效的参考依据.     

GaAs基β辐射伏特效应微电池的参量优化设计研究

考虑放射性同位素源自吸收效应,提出基于半导体材料GaAs和同位素源⁶³Ni的微电池最优化设计方案,并通过蒙特卡罗程序MCNP模拟计算β粒子在半导体材料中的输运过程,对同位素源与半导体材料的厚度,换能单元PN结结深、耗尽区宽度、掺杂浓度、少子扩散长度,及电子空穴对的产生及收集情况等进行了研究和分析,给出了不同结深下,各物理参量的最佳设计值。在源活度为3.7×10⁷ Bq,PN结表面积为0.01 cm²时,提出的辐射伏特效应微电池最优化设计方案可实现：短路电流密度为379.68 nA/cm²,开路电压为1.375 V,填充因子为84.39%, 最大输出功率为440.4 nW/cm²,能量转化率为4.34%。     

Further studies on the lithium phosphorus oxynitride solid electrolyte

First step in the way to the fabrication of an all-solid microbattery for autonomous wireless sensor node, amorphous thin solid films of lithium phosphorus oxynitride (LiPON) were prepared by radio-frequency sputtering of a mixture target of P₂O₅/Li₂O in ambient nitrogen atmosphere. The morphology, composition, and ionic conductivity were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and A.C. impedance spectroscopy. With a thickness of 1.4 μm, the obtained LiPON amorphous layer provided an ionic conductivity close to 6 × 10⁻⁷ S cm⁻¹ at room temperature. MicroRaman UV spectroscopy study was successfully carried out for the first time on LiPON thin films to complete the characterization and bring further information on LiPON structure.