B. F. Hung

Very high K and high density TiTaO MIM capacitors for analog and RF applications

For the first time, high density (10.3 fF//spl mu/m/sup 2/), low voltage linearity (/spl alpha/=89 ppm/V/sup 2/) and small leakage current (1.2/spl times/10/sup -82/ A/cm/sup 2/ or 5.8 fA/[pF/spl middot/V] at 2V) meet all the ITRS requirements of analog capacitor at year 2018. These are achieved by novel high-K TiTaO (K=45) and high work-function Ir capacitor, which further improve to very high 23 fF//spl mu/m/sup 2/ density and low 81 ppm/V/sup 2/ linearity for higher speed analog/RF ICs at 1GHz, using the fast /spl alpha/ decay mechanism with increasing frequency.

High-Temperature Stable HfLaON p-MOSFETs With High-Work-Function

We report a novel 1000 degC stable HfLaON p-MOSFET with Ir3 Si gate. Low leakage current of 1.8times10-5 A/cm2 at 1 V above flat-band voltage, good effective work function of 5.08 eV, and high mobility of 84 cm2/Vmiddots are simultaneously obtained at 1.6 nm equivalent oxide thickness. This gate-first p-MOSFET process with self-aligned ion implant and 1000 degC rapid thermal annealing is fully compatible to current very large scale integration fabrication lines

\hbox{Ir}_{3}\hbox{Si}

The authors have fabricated low-temperature fully silicided YbSi/sub 2-x/-gated n-MOSFETs that used an HfAlON gate dielectric with a 1.7-nm EOT. After a 600 /spl deg/C rapid thermal annealing, these devices displayed an effective work function of 4.1 eV and a peak electron mobility of 180 cm/sup 2//V/spl middot/s. They have additional merit of a process compatible with current very large scale integration fabrication lines.

Gate

A novel 1000 degC-stable IrxSi gate on HfSiON is shown for the first time with full process compatibility to current very-large-scale-integration fabrication lines and proper effective work function of 4.95 eV at 1.6-nm equivalent-oxide thickness. In addition, small threshold voltages and good hole mobilities are measured in IrxSi/HfSiON transistors. The 1000 degC thermal stability above pure metal (900 degC only) is due to the inserted 5-nm amorphous Si, which also gives less Fermi-level pinning by the accumulated metallic full silicidation at the interface

HfAlON n-MOSFETs incorporating low-work function gate using ytterbium silicide

High-performance polycrystalline silicon (poly-Si) thin-film transistors (TFTs) with oxide/nitride/xynitride (ONO) multilayer gate dielectrics were fabricated. The low-temperature (≤300°C) ONO multilayer dielectric uses three stacked layers: the bottom layer is a very thin N 2 O-plasma oxynitride deposited by plasma-enhanced chemical vapor deposition (PECVD), the middle layer is PECVD Si 3 N 4 , and the top layer is tetraethoxysilane (TEOS) oxide. The ONO gate dielectric on poly-Si films shows a very high breakdown field of 9.4 MV/cm, a longer time-dependent dielectric breakdown lifetime and a lower charge trapping rate than single-layer PECVD TEOS oxide or nitride. The fabricated poly-Si TFTs with ONO gate dielectric exhibited excellent transfer characteristics, high field-effect mobility of 213 cm 2 /V s, and an ON/OFF current ratio of over 10 8 .

High-Temperature Stable

The authors have developed a novel high-temperature stable HfSi x gate for high-kappa HfSiON gate dielectric. After a 1000 degC RTA, the HfSix/HfSiON devices showed an effective work function of 4.27 eV and a peak electron mobility of 216 cm2/Vmiddots at 1.6-nm equivalent oxide thickness, with additional merit of a process compatible with current very large scale integration fabrication lines

\hbox{Ir}_{x}\hbox{Si}

We report the growth of an ultrathin 1.0 nm (equivalent oxide thickness = 0.86 nm) oxynitride gate dielectric by rapid thermal processing (RTP) in high-N 2 but low-O 2 gas flow ambient. The effect of the changing N 2 /O 2 gas flow ratio on the characteristics of oxynitride films was investigated. High-quality oxynitride film could be formed by RTP in an optimum N 2 /O 2 gas flow ratio of 5/1. Detailed characterization (transmission electron microscopy, J-E capacitance-voltage, stress-induced leakage current, charge-trapping properties) demonstrated the high quality of the oxynitride dielectric and showed that low leakage current density J g = 0.1 A/cm 2 at I V, was 1.85 orders of magnitude lower than that of SiO 2 . These improvements are attributed to the presence of nitrogen at the interface and in the hulk of the oxynitride.

Gates With High Work Function on HfSiON p-MOSFETs

This paper developed a novel polycrystalline silicon (poly-Si) thin-film transistor (TFT) structure with the following special features: 1) a new oxide-nitride-oxynitride (ONO) multilayer gate dielectric to reduce leakage current, improved breakdown characteristics, and enhanced reliability; and 2) raised source/drain (RSD) structure to reduce series resistance. These features were used to fabricate high-performance RSD-TFTs with ONO gate dielectric. The ONO gate dielectric on poly-Si films shows a very high breakdown field of 9.4 MV/cm, a longer time dependent dielectric breakdown, larger Q/sub BD/, and a lower charge-trapping rate than single-layer plasma-enhanced chemical vapor deposition tetraethooxysilane oxide or nitride. The fabricated RSD-TFTs with ONO gate dielectric exhibited excellent transfer characteristics, high field-effect mobility of 320 cm/sup 2//V/spl middot/s, and an on/off current ratio exceeding 10/sup 8/.

Low-temperature poly-si thin-film transistor with a N2O-Plasma ONO multilayer gate dielectric

A low minimum noise figure (NFmin) of 1.2 dB and high associated gain of 12.8 dB at 10 GHz, were measured for 0.18 µm RF MOSFETs on plastic, made by substrate thinning (~30 µm), transfer and bonding. The performance can be further improved to 0.96 dB NFmin and 14.1 dB associated gain at 10 GHz, under applied tensile strain, using flexible Si on plastic. A 3.5 nH inductor on plastic showed a 55% higher Q-factor with a wider frequency range, compared with that on a Si substrate. Index Terms — RF Noise, associated gain, MOSFET, plastic.

HfSiON n-MOSFETs Using Low-Work Function

A very low minimum noise figure (NF/sub min/) of 1.2 dB and a high associated gain of 12.8 dB at 10 GHz were measured for six-finger, 0.18-/spl mu/m radio frequency (RF) metal-oxide semiconductor field-effect transistors mounted on insulating plastic following substrate-thinning (/spl sim/30 /spl mu/m) and wafer transfer. Before this process, the devices had a slightly better RF performance of 1.1-dB NF/sub min/ and a 13.7-dB associated gain. The small RF performance degradation of the active transistors transferred to plastic shows the potential of integrating electronics onto plastic.