Jenkins Melanie A, Holden Konner E K, Smith Sean W, Brumbach Michael T, Henry M David, Weiland Conan, Woicik Joseph C, Jaszewski Samantha T, Ihlefeld Jon F, Conley John F
School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97330, United States.
Sandia National Laboratories, Albuquerque, New Mexico 87185, United States.
ACS Appl Mater Interfaces. 2021 Mar 31;13(12):14634-14643. doi: 10.1021/acsami.0c17729. Epub 2021 Mar 22.
Doped ferroelectric HfO is highly promising for integration into complementary metal-oxide semiconductor (CMOS) technology for devices such as ferroelectric nonvolatile memory and low-power field-effect transistors (FETs). We report the direct measurement of the energy barriers between various metal electrodes (Pt, Au, Ta, TaN, Ti/Pt, Ni, Al) and hafnium zirconium oxide (HfZrO, HZO) using internal photoemission (IPE) spectroscopy. Results are compared with valence band offsets determined using the three-sample X-ray photoelectron spectroscopy (XPS) as well as the two-sample hard X-ray photoelectron spectroscopy (HAXPES) techniques. Both XPS and IPE indicate roughly the same dependence of the HZO barrier on metal work function with a slope of 0.8 ± 0.5. XPS and HAXPES-derived barrier heights are on average about 1.1 eV smaller than barrier heights determined by IPE, suggesting the presence of negative charge in the HZO.
掺杂铁电铪氧化物在集成到互补金属氧化物半导体（CMOS）技术中用于制造铁电非易失性存储器和低功耗场效应晶体管（FET）等器件方面极具前景。我们报告了使用内光电发射（IPE）光谱法直接测量各种金属电极（Pt、Au、Ta、TaN、Ti/Pt、Ni、Al）与铪锆氧化物（HfZrO，HZO）之间的能垒。将结果与使用三样品X射线光电子能谱（XPS）以及两样品硬X射线光电子能谱（HAXPES）技术测定的价带偏移进行了比较。XPS和IPE均表明HZO能垒对金属功函数的依赖性大致相同，斜率为0.8±0.5。XPS和HAXPES得出的能垒高度平均比IPE测定的能垒高度小约1.1 eV，这表明HZO中存在负电荷。
