Browsing by Author "Hou, F. -J."

Now showing 1 - 5 of 5

A Comprehensive Study of Polymorphic Phase Distribution of Ferroelectric-Dielectrics and Interfacial Layer Effects on Negative Capacitance FETs for Sub-5 nm Node
(2018-01-01)
Tang, Y. -T
;
Su, C. -J.
;
Wang, Y. -S.
;
Kao, K. -H.
;
Wu, T. -L.
The impact of a realistic representation of gate-oxide granularity on negative-capacitance (NC) FETs at sub-5nm node is studied by a newly developed thermodynamic energy model based on the first principle calculation (FPC). For the first time, the calculation fully couples the Landau-Khalatnikov (L-K) equation with grain-size effect equation in NC-FETs. It explains the experimental results in phase transition and reveals excellent immunity against depolarization in ferroelectric (FE) layer owing to dopant concentration and stress in thin films. A sub-5nm node (L-G=10nm) NC-FET with thin FE layer (T-FE similar to 2nm) is integrated to achieve low subthreshold slope (SS) of 52mV/dec via a 1.9GPa-tensor stressed interfacial layer (IL) and 12% Zr-doped HfO2.
Ge FinFET CMOS Inverters With Improved Channel Surface Roughness by Using In-Situ ALD Digital O-3 Treatment
(2018-01-01)
Yeh, M. -S.
;
Luo, G. -L.
;
Hou, F. -J.
;
Sung, P. -J.
;
Wang, C. -J.
Improved electrical characteristics of CMOS inverters composed of Ge n- and p-finFETs were demonstrated by utilizing newly introduced Ge surface treatments. In-situ digital O-3 treatment in ALD chamber was adopted on the surface of Ge fin sidewall in order to reduce the roughness and etching damages through the GeO desorption mechanism. The treatment effects were checked by AFM and C-V measurements. By combining this treatment with optimized microwave annealing, sub-threshold slope and the I-ON/I-OFF ratio were remarkably improved in both n-finFET and p-finFET, and Ge CMOS inverters with high voltage gain of 50.3 V/V at low V-D = 0.6 V was realized. Finally, simulations on an ideal Ge CMOS inverter were presented.
Ge Nanowire FETs with HfZrOx Ferroelectric Gate Stack Exhibiting SS of Sub-60 mV/dec and Biasing Effects on Ferroelectric Reliability
(2017-01-01)
Su, C. -J.
;
Hong, T. -C.
;
Tsou, Y. -C.
;
Hou, F. -J.
;
Sung, P. -J.
Ge nanowire (NW) FETs exhibiting subthreshold swing (SS) of 54 mV/dec at room temperature are demonstrated with ferroelectric HfZrOx (FE-HZO) gate stack for the first time. I-ON/I-OFF ratios higher than 10(7) and 10(6) for p- and n-NWFETs, respectively, have been achieved by adopting the gate-all-around (GAA) configuration. Electrical biasing effects on the HZO ferroelectric reliability have been systematically investigated in this work. It is found that the polarization behavior will degrade with electrical stress time and can be recovered. The Ge HZO FinFET CMOS inverter shows experimentally voltage gain of 24.8 V/V.
High Performance Silicon N-channel Gate-All-Around Junctionless Field Effect Transistors by Strain Technology
(2016)
Sung, P. -J.
;
Cho, T. -C.
;
Chen, P. -C.
;
Hou, F. -J.
;
Lai, C. -H
In this paper, strain effects on silicon n-channel gate-allaround (GAA) jucntionless field effect transistor (JLFET) are studied. By using tensile strain SiN layer, drive currents of the JLFETs show enhancement of up to 42%. The high performance strained JLFETs exhibit superior gate control (I-on/I-off > 10(9)) and ideal S.S. (65 mV/dec.) as a channel width scales down to 20 nm. Drive currents and leakage currents are improved simultaneously after inducing strain technology.
Voltage Transfer Characteristic Matching by Different Nanosheet Layer Numbers of Vertically Stacked Junctionless CMOS Inverter for SoP/3D-ICs applications
(2018-01-01)
Sung, P. -J.
;
Chang, C. -Y.
;
Chen, L. -Y.
;
Kao, K. -H.
;
Su, C. -J.
For the first time, CMOS inverters with different numbers of vertically stacked junctionless (JL) nanosheets (NSs) are demonstrated. All fabrication steps were below 600 degrees C, and 8-nm thick poly-Si NSs with smooth surface roughness were formed by a dry etching process. Compared to single channel devices, stacked n/p-channel FETs exhibit higher on-current with low leakage current. Furthermore, a common-gate process was performed for the fabrication of CMOS inverters. By adjusting the NS layer numbers for n/pFETs, respectively, the voltage transfer characteristics (VTCs) of the CMOS inverter can be matched much better to reduce the noise margin due to on-current matching without area penalty. This work experimentally demonstrates a new configuration of CMOS inverters on stacked NSs, which is promising for System-on-Panel (SoP) and 3D-ICs applications.