Results in Physics ( IF 4.4 ) Pub Date : 2020-10-15 , DOI: 10.1016/j.rinp.2020.103500 A.R. Zanatta
The phonon behavior of various Ge-based samples has been investigated in great detail. The study comprised Ge films (amorphous and partially crystallized and alloyed with oxygen), crystalline Ge wafers (pristine and alloyed with oxygen), and GeO2 powder. The oxygen-containing samples obtained after thermal annealing the Ge film and Ge wafer correspond to sub-stoichiometric GeO2, or the so-called Ge + GeOx system, in which case [O] ∼40 at.%. A thorough examination of this Ge + GeOx system – as provided by temperature-dependent Raman scattering, their analysis according to the existing theoretical models (involving anharmonic phonon coupling and thermal expansion processes), and a critical review of the literature – indicates the coexistence of practically independent Ge–Ge- and Ge–O-related structures and confirms the presence of both structural and chemical (dis)order. Moreover, the main features regarding the phonon frequencies (), line widths (), and scattering intensities () of the Ge + GeOx system suggest their suitability in temperature sensing applications. Accordingly, experimentally determined reference curves (i.e., , , and data described in terms of simple mathematical functions) gave rise to temperature accuracies on the order of 20 K. Everything considered, in its current form, this work presents the first comprehensive analysis-discussion regarding the Ge + GeOx system that, additionally, is being proposed as an effective medium for optical thermometric applications.
中文翻译:
Ge + GeO x系统的温度依赖性拉曼散射及其作为光学温度计的潜力
已经对各种锗基样品的声子行为进行了详细研究。该研究包括Ge膜(非晶和部分结晶并与氧形成合金),结晶Ge晶片(原始且与氧形成合金)和GeO 2粉末。Ge膜和Ge晶片热退火后获得的含氧样品对应于亚化学计量的GeO 2或所谓的Ge + GeO x系统,在这种情况下[O]〜40 at。%。对该Ge + GeO x进行彻底检查由依赖温度的拉曼散射,根据现有理论模型(涉及非谐声子耦合和热膨胀过程)进行的分析以及对文献的严格审查提供的系统表明,实际上独立的Ge-Ge-和Ge共存-O相关结构,并确认结构和化学(无序)结构均存在。此外,关于声子频率的主要特征(),线宽()和散射强度(Ge + GeO x系统的)表明它们适用于温度传感应用。因此,通过实验确定的参考曲线(即,, 和 根据简单的数学函数描述的数据)产生了约20 K的温度精度。在目前的形式下,所有考虑的工作都提出了有关Ge + GeO x系统的首次综合分析讨论,此外,被提议作为光学测温应用的有效介质。