n型层的取决于应变的粒度边界特性
Kota Igura1, Koki Nozawa2, Takamitsu Ishiyama1,3
1Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8573, Japan.
Scientific reports
|April 2, 2024
概括
应变显著影响多晶 (Ge) 薄膜. 压缩应变增加了颗粒大小,但由于颗粒边界效应减少了电子流动性,为Ge设备增强提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 半导体技术 半导体技术
背景情况:
- 多晶 (Ge) 薄膜对于电子和光学设备至关重要.
- 最近的进展包括低温固体相结晶,在Ge膜中实现高电子流动性.
研究的目的:
- 研究应变对n型多晶Ge层的晶体和电性质的影响.
- 了解控制压力诱导性质变化的基本机制.
主要方法:
- 在多晶Ge层中调节应变,使用具有不同热膨胀系数的GeOx中间层和基板.
- 应用于从0.6% (拉力) 到-0.8% (压缩) 的应变.
主要成果:
- 压缩应变使颗粒大小扩大到12微米,但电子流动性降低.
- 温度依赖的移动性分析表明,压力会影响谷物边界的潜在屏障高度.
- 对于n型和p型Ge的粒度边界屏障高度观察到相反的应变依赖行为,这表明有压电效应.
结论:
- 应变工程是一种可行的策略,可以调整多晶格质薄膜的性能.
- 压电效应在压力诱导的颗粒边界特性调制中起着关键作用.
- 结果为改善Ge设备性能和更深入地了解多晶半导体提供了指导方针.
相关概念视频
P-N junction
525
A p-n junction is formed when p-type and n-type semiconductor materials are joined together. At the interface of the p-n junction, holes from the p-side and electrons from the n-side begin to diffuse into the opposite sides due to the concentration gradient. This diffusion of carriers leads to a region around the junction where there are no free charge carriers, known as the depletion region. The charge density within the depletion region for the n-side and p-side can be described by the...
525
Metal-Semiconductor Junctions
350
The contact of metal and semiconductor can lead to the formation of a junction with either Schottky or Ohmic behavior.
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
350
Types of Semiconductors
591
Intrinsic semiconductors are highly pure materials with no impurities. At absolute zero, these semiconductors behave as perfect insulators because all the valence electrons are bound, and the conduction band is empty, disallowing electrical conduction. The Fermi level is a concept used to describe the probability of occupancy of energy levels by electrons at thermal equilibrium. In intrinsic semiconductors, the Fermi level is positioned at the midpoint of the energy gap at absolute zero. When...
591
Fermi Level Dynamics
245
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
245
Biasing of P-N Junction
528
The operation of a p-n junction diode involves various biasing conditions, including forward bias, reverse bias, and equilibrium.
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
528
Carrier Transport
435
The generation of electrical current in semiconductors is fundamentally driven by two mechanisms: drift and diffusion. These processes are essential for the functionality and performance of semiconductor-based devices.
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
435


