%0 Journal Article %1 9390309 %A Choudhary, Sumit %A Schwarz, Daniel %A Funk, Hannes S. %A Khosla, Robin %A Sharma, Satinder K. %A Schulze, Jörg %D 2021 %J IEEE Transactions on Nanotechnology %K iht j.schulze.iht journal %P 346-355 %R 10.1109/TNANO.2021.3069820 %T Impact of Charge Trapping On Epitaxial p-Ge_-on-p-Si and HfO₂ Based Al/HfO₂/p-Ge_-on-p-Si/Al Structures Using Kelvin Probe Force Microscopy and Constant Voltage Stress %V 20 %X The quest for the high speed, low power digital logic circuits urge an imperative demand of compatible high-κ dielectric integration on novel Germanium (Ge) based channel material. Here, first ever a methodical nanoscopic and microscopic probes were attempted to Atomic Layer Deposited, Hafnium Dioxide (HfO₂) dielectrics on Molecular Beam Epitaxy (MBE) of p-Ge_-on-p-Si stack. Kelvin Probe Force Microscopy based contact potential difference (CPD) analysis reveals that the disintegration of trapped charges lasting for ~18 hours. The impact of constant voltage stress (CVS) on trapped charges results in variation of threshold voltage (V_th) and hysteresis window (W) were studied. The cyclic Capacitance-Voltage (C-V) characteristics at 0.5 MHz exhibit the shift in the flat band (ΔV_fb), ΔV_th, and ΔW at 10V stress were ~0.84V, ~0.62V, and ~0.47V, respectively. While the computed interface trap density (D_it) and total effective charge density (Q_eff) were ~8.49 × 10¹² eV^-1cm^-2 and ~1.81 × 10¹² cm^-2_, respectively. The gate leakage current density, (J) at 5V is 26.53 × 10^-6 A/cm² and reduced by a factor of ~6.8 after 10V, CVS. Whereas the current density (J) increases from ~26.53 × 10^-6 A/cm² at 25 °C by a factor of ~2 at 125 °C. To study the retention and effect of charge trapping, the stress-time analysis was performed for 8000s at 3V (CVS). The r.m.s. surface roughness of HfO₂ thin films was found to be ~0.23 nm. X-ray photoelectron spectroscopy (XPS) depth profiling categorized the elemental composition of thin films. These investigations would help to HfO₂/p-Ge_-on-p-Si system interfacial engineering well before the Ge based nano device realization.

@article{9390309, abstract = {The quest for the high speed, low power digital logic circuits urge an imperative demand of compatible high-κ dielectric integration on novel Germanium (Ge) based channel material. Here, first ever a methodical nanoscopic and microscopic probes were attempted to Atomic Layer Deposited, Hafnium Dioxide (HfO₂) dielectrics on Molecular Beam Epitaxy (MBE) of p-Ge_-on-p-Si stack. Kelvin Probe Force Microscopy based contact potential difference (CPD) analysis reveals that the disintegration of trapped charges lasting for ~18 hours. The impact of constant voltage stress (CVS) on trapped charges results in variation of threshold voltage (V_th) and hysteresis window (W) were studied. The cyclic Capacitance-Voltage (C-V) characteristics at 0.5 MHz exhibit the shift in the flat band (ΔV_fb), ΔV_th, and ΔW at 10V stress were ~0.84V, ~0.62V, and ~0.47V, respectively. While the computed interface trap density (D_it) and total effective charge density (Q_eff) were ~8.49 × 10¹² eV^-1cm^-2 and ~1.81 × 10¹² cm^-2_, respectively. The gate leakage current density, (J) at 5V is 26.53 × 10^-6 A/cm² and reduced by a factor of ~6.8 after 10V, CVS. Whereas the current density (J) increases from ~26.53 × 10^-6 A/cm² at 25 °C by a factor of ~2 at 125 °C. To study the retention and effect of charge trapping, the stress-time analysis was performed for 8000s at 3V (CVS). The r.m.s. surface roughness of HfO₂ thin films was found to be ~0.23 nm. X-ray photoelectron spectroscopy (XPS) depth profiling categorized the elemental composition of thin films. These investigations would help to HfO₂/p-Ge_-on-p-Si system interfacial engineering well before the Ge based nano device realization.}, added-at = {2021-11-11T13:13:21.000+0100}, author = {Choudhary, Sumit and Schwarz, Daniel and Funk, Hannes S. and Khosla, Robin and Sharma, Satinder K. and Schulze, Jörg}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2b19ab474492c946fa0aa26765c4e982e/ihtpublikation}, description = {Impact of Charge Trapping On Epitaxial p-Ge-on-p-Si and HfO2 Based Al/HfO2/p-Ge-on-p-Si/Al Structures Using Kelvin Probe Force Microscopy and Constant Voltage Stress | IEEE Journals & Magazine | IEEE Xplore}, doi = {10.1109/TNANO.2021.3069820}, interhash = {3a1a663cd6ab15e9d48f480cd477824d}, intrahash = {b19ab474492c946fa0aa26765c4e982e}, issn = {1941-0085}, journal = {IEEE Transactions on Nanotechnology}, keywords = {iht j.schulze.iht journal}, pages = {346-355}, timestamp = {2021-11-11T12:13:21.000+0100}, title = {Impact of Charge Trapping On Epitaxial p-Ge_-on-p-Si and HfO₂ Based Al/HfO₂/p-Ge_-on-p-Si/Al Structures Using Kelvin Probe Force Microscopy and Constant Voltage Stress}, volume = 20, year = 2021 }