Advanced FinFET Technology: TiN Metal-gate CMOS and 3T/4T Device Integration

IEEE Trans. Nanotechnology

Kijima

Sugimata

et al. 2006

107

The titanium nitride (TiN) gate electrode with a tunable work function has successfully been deposited on the sidewalls of upstanding Si-fin channels of FinFETs by using a conventional reactive sputtering. It was found that the work function of the TiN ( TiN ) slightly decreases with increasing nitrogen (N 2 ) gas flow ratio, = N 2 (Ar + N 2 ) in the sputtering, from 17% to 100%. The experimental threshold voltage ( th ) dependence on the shows that the more offers the lower th for the TiN gate n-channel FinFETs. The composition analysis of the TiN films with different showed that the more amount of nitrogen is introduced into the TiN films with increasing , which suggests that the lowering of TiN with increasing should be related to the increase in nitrogen concentration in the TiN film. The desirable th shift from 0.22 to 0.22 V was experimentally confirmed by fabricating n + poly-Si and TiN gate n-channel multi-FinFETs without a channel doping. The developed simple technique for the conformal TiN deposition on the sidewalls of Si-fin channels is very attractive to the TiN gate FinFET fabrication.

Section: Introductionmentioning

confidence: 93%

Investigation of the TiN Gate Electrode With Tunable Work Function and Its Application for FinFET Fabrication

IEEE Trans. Nanotechnology

Kijima

Sugimata

et al. 2006

107

“…As the starting material, we used lightly doped p-type (110)-oriented silicon-on-insulator (SOI) wafers to fabricate ideal rectangular cross-sectional Si-fin channels by orientation-dependent wet etching. [13][14][15][16] First, fin patterns were delineated parallel to the h112i direction by EB lithography and fin hard masks were formed by RIE, as shown in Figs. 1(b)- (2).…”

Section: Device Fabricationmentioning

confidence: 99%

“…[6][7][8][9][10][11][12] Very recently, the sputtered TiN gate has actively been applied in FinFETs because its midgap work function provides well symmetrical V th for FinFET CMOS without channel doping. [13][14][15][16] Moreover, it has been reported that the work function of sputtered TiN can be slightly adjusted by changing the nitrogen gas flow ratio R N ¼ N 2 =ðAr þ N 2 Þ during sputtering. 12,17) However, the R N dependences of the electrical characteristics of sputtered TiN gate bulk planar MOSFETs and FinFETs have not been investigated sufficiently.…”

Section: Introductionmentioning

confidence: 99%

A Comparative Study of Nitrogen Gas Flow Ratio Dependence on the Electrical Characteristics of Sputtered Titanium Nitride Gate Bulk Planar Metal–Oxide–Semiconductor Field-Effect Transistors and Fin-Type Metal–Oxide–Semiconductor Field-Effect Transistors

Hayashida

Matsukawa

et al. 2009

jjap

A simple apparatus which measures the complex petmeability of soft magnetic thin films is described. A continuous frequency spectrum from 100 kHz lo 200 MHz is measured with high accuracy (1 pm) in permeance by averaging the repeated scanning data to increase the signal-to-noise ratio. The relationship between the anisotropy field and the permeability is studied for Co-based amorphous sol1 magnetic thin films with various uniaxial anisotropy fields by using this apparatus. The high-frequency permeability shows a rapid drop from a much lower lrequency than that estimated by a classical eddy current theory. From an analysis 01 the permeability spectrum. the frequency, which takes the maximum value in the imaginary part of the permeability, seems to correspond to the natural ferromagnetic resonance frequency. It is concluded that the main cause for the drop in the permeability in the high-frequency region is the natural ferromagnetic resonance of uniaxial anisotropic soit magnetic thin films.

“…[3][4][5][6][7][8][9][10][11] Very recently, the PVD-TiN gate has actively been developed for fin-type double-gate MOSFETs (FinFETs) because its midgap work function offers a symmetrical threshold voltage (V th ) for FinFET CMOS without channel doping. [12][13][14][15][16][17][18][19][20][21] One of the most important issues in PVD-TiN gate FinFET fabrication is PVD-TiN gate formation especially the PVD-TiN etching on the sidewalls of tall fin-channels by conventional reactive ion etching (RIE) owing to the low volatility of titanium (Ti) halogenides. 22,23) Since the effective channel width W eff in FinFETs is twice the fin height H fin , W eff ¼ 2H fin , a tall finchannel is very attractive for realizing a high drive current without increasing device area.…”

Section: Introductionmentioning

confidence: 99%

Nanoscale Wet Etching of Physical-Vapor-Deposited Titanium Nitride and Its Application to Sub-30-nm-Gate-Length Fin-Type Double-Gate Metal–Oxide–Semiconductor Field-Effect Transistor Fabrication

Kamei

Endo

et al. 2010

Jpn. J. Appl. Phys.

The nanoscale wet etching of physical-vapor-deposited (PVD) titanium nitride (TiN) and its application to sub-30-nm-gate-length fin-type double-gate metal–oxide–semiconductor field-effect transistor (FinFET) fabrication are systematically investigated. It is experimentally found that PVD-TiN side-etching depth can be controlled to be one-half of PVD-TiN thickness with precise time control using an ammonium hydroxide (NH4OH) : hydrogen peroxide (H2O2) : deionized water (H2O) = 1 : 2 : 5 solution at 60 °C. Using the developed nanoscale PVD-TiN wet etching technique, sub-30-nm-physical-gate-length FinFETs, 100-nm-tall fin-channel complementary MOS (CMOS) inverters and static random access memory (SRAM) half-cells have successfully been fabricated and demonstrated. These experimental results indicate that the developed nanoscale PVD-TiN wet etching technique is very useful for tall fin-channel CMOS fabrication.