Browsing by Author "Cho, BJ"

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A high-density MIM capacitor (13 fF/mu m(2)) using ALD HfO2 dielectrics
(2003-02-01)
Yu, XF
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Zhu, CX
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Hu, H
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Chin, A
;
Li, MF
Metal-insulator-metal (MIM) capacitors with a different thickness of HfO2 have been investigated. The results show that both the capacitance density and voltage coefficients of capacitance (VCCs) increase with decreasing the HfO2 thickness. In addition, it is also found that the VCCs decrease logarithmically with increasing the thickness Of HfO2. Furthermore, the MIM capacitor with 10-nm HfO2 shows a record high capacitance density of 13 fF/mum(2) and a VCC of 607 ppm/V, which can meet the requirement of the International Technology Roadmap for Semiconductors. It can also provide a low leakage current of 5.95 x 10-(8)A/cm(2) at room temperature at I V, low tangent values below 0.05, and a small frequency dependence as well. All these indicate that it is very suitable for use in silicon integrated circuit applications.
Al2O3-Ge-On-insulator n- and p-MOSFETs with fully NiSi and NiGe dual gates
(2004-03-01)
Yu, DS
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Huang, CH
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Chin, A
;
Zhu, CX
;
Li, MF
High-kappa, A1(2)O(3)/Ge-on-insulator (GOI) n- and p-MOSFETs with fully silicided NiSi and germanided NiGe dual gates were fabricated. At 1.7-nm equivalent-oxide-thickness (EOT), the A1(2)O(3)-GOI with metal-like NiSi and NiGe gates has comparable gate leakage current with A1(2)O(3)-Si MOSFETs. Additionally, A1(2) O-3-GOI C-MOSFETs with fully NiSi and NiGe gates show 1.94 and 1.98 times higher electron and hole mobility, respectively, than A1(2)O(3)-Si devices, because the electron and hole effective masses of Ge are lower than those of Si. The process with maximum 500 degreesC rapid thermal annealing (RTA) is ideal for integrating metallic gates with high-kappa to minimize interfacial reactions and crystallization of the high-kappa material, and oxygen penetration in high-kappa MOSFETs.
Effect of surface NH3 anneal on the physical and electrical properties of HfO2 films on Ge substrate
(2004-05-10)
Wu, N
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Zhang, QC
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Zhu, CX
;
Yeo, CC
;
Whang, SJ
Metal-oxide-semiconductor capacitors were fabricated on germanium substrates by using metalorganic-chemical-vapor-deposited HfO2 as the dielectric and TaN as the metal gate electrode. It is demonstrated that a surface annealing step in NH3 ambient before the HfO2 deposition could result in significant improvement in both gate leakage current and the equivalent oxide thickness (EOT). It was possible to achieve a capacitor with an EOT of 10.5 Angstrom and a leakage current of 5.02x10(-5) A/cm(2) at 1 V gate bias. X-ray photoelectron spectroscopy analysis indicates the formation of GeON during surface NH3 anneal. The presence of Ge was also detected within the HfO2 films. This may be due to Ge diffusion at the high temperature (similar to400 degreesC) used in the chemical-vapor deposition process. (C) 2004 American Institute of Physics.
Fully silicided NiSi and germanided NiGe dual gates on SiO2/Si and Al2O3/Ge-on-insulator MOSFETs
(2003)
Huang, CH
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Yu, DS
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Chin, A
;
Wu, CH
;
Chen, WJ
We demonstrate for the first time fully silicided NiSi (4.55eV) and germanided NiGe (5.2eV) dual gates on 1.9nm-SiO2/Si and Al2O3/Ge-On-Insulator (GOI) MOSFETs (EOT = 1.7nm). In additional to the comparable gate current and time-to-breakdown with AI gate C-MOSFETs, the fully NiSi and NiGe gates on SiO2/Si show mobility close to universal mobility while on Al2O3/GOI show similar to2.0X higher peak electron and hole mobility than Al on Al2O3/Si with special advantage of NiSi and NiGe compatible to current VLSI process line.
High-performance MIM capacitor using ALD high-k HfO2-Al2O3 laminate dielectrics
(2003-12-01)
Ding, SJ
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Hu, H
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Lim, HF
;
Kim, SJ
;
Yu, XF
For the first time, we successfully fabricated and demonstrated high performance metal-insulator-metal (MIM) capacitors with HfO2-Al2O3 laminate dielectric' using atomic im layer deposition (ALD) technique. Our data indicates that the laminate NUM capacitor can provide high capacitance density of 12.8 fF/ mum(2) from 10 kHz up to 20 GHz, very low leakage current of 3.2 x 10(-8) A/cm(2) at 3.3 V, small linear voltage coefficient of capacitance of 240 ppm/V together with quadratic. one of 1830 PPM/V-2, temperature coefficient of capacitance of 182 ppm/degreesC, and high breakdown field of similar to6 MV/cm as well as promising reliability. As a result, the HfO2-Al2O3 laminate is a very promising candidate for next generation MINI capacitor for radio frequency and mixed signal integrated circuit applications.
Lanthanide (Tb)-doped HfO2 for high-density MIM capacitors
(2003-07-01)
Kim, SJ
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Cho, BJ
;
Li, MF
;
Zhu, CX
;
Chin, A
A high-density metal-insulator-metal (MIM) capacitor with a lanthanide-doped HfO2 dielectric prepared by physical vapor deposition (PVD) is presented for the first time. A significant improvement was shown in both the voltage coefficient of capacitance (VCC) and the leakage current density of MIM capacitor, yet the high capacitance density of HfO2 dielectrics was maintained by achieving the doping of Tb with an optimum concentration in HfO2. This technique allows utilizing thinner dielectric film in MIM capacitors and achieving a capacitance density as high as 13.3 fF/mum(2) with leakage current and VCC values that fully meet requirements from year 2005 for radio frequency (RF) bypass capacitors applications.
PVD HfO2 for high-precision MIM capacitor applications
(2003-06-01)
Kim, SJ
;
Cho, BJ
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Li, MF
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Yu, XF
;
Zhu, CX
Metal-insulator-metal (MIM) capacitors are fabricated using sputtered HfO2 with Ta and TaN for top and bottom electrodes, respectively. High-capacitance densities from 4.7 to 8.1 fF/mum(2) have been achieved while maintaining the leakage current densities around 1 x 10(-8) A/cm(2) within the normal circuit bias conditions. A guideline for the insulator thickness and its dielectric constant has been obtained by analyzing the tradeoff between the linearity coefficient and the capacitance density.
RF, DC, and reliability characteristics of ALD HfO2-Al2O3 laminate MIM capacitors for Si RF IC applications
(2004-06-01)
Ding, SJ
;
Hu, H
;
Zhu, CX
;
Kim, SJ
;
Yu, XF
High-performance metal-insulator-metal capacitors using atomic layer-deposited HfO2-Al2O3 laminate are fabricated and characterized for RF and mixed-signal applications. The laminate capacitor can offer high capacitance density (12.8 fF/mum(2)) up to 20 GHz, low leakage current of 4.9 x 10(-8) A/cm(2) at 2 V and 125 degreesC, and small linear voltage coefficient of capacitance of 211 ppm/V at 1 MHz, which can easily satisfy RF capacitor requirements for year 2007 according to the International Technology Roadmap for Semiconductors. In addition, effects of constant voltage stress and temperature on leakage current and voltage linearity are comprehensively investigated, and dependences of quadratic voltage coefficient of capacitance (alpha) on frequency and thickness are also demonstrated. Meanwhile, the underlying mechanisms are also discussed.
Very high density RF MIM capacitors (17 fF/mu m(2) using high-kappa Al2O3 doped Ta2O5 dielectrics
(2003-10-01)
Yang, MY
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Huang, CH
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Chin, A
;
Zhu, CX
;
Cho, BJ
Using high-kappa, Al2O3 doped Ta2O5 dielectric, we have obtained record high MINI capacitance density of 17 fF/mum(2) at 100 KHz, small 5% capacitance reduction to RF frequency range, and low leakage current density of 8.9 x 10(-7) A/cm(2). In combination of both high capacitor density and low leakage current density, a very low leakage current of 5.2 x 10(-12) A is calculated for a typical large 10 pF capacitor used in RF IC that is even smaller than that of a deep sub-mum MOSFET. This very high capacitance density with good MINI capacitor characteristics can significantly reduce the chip size of RF ICs.