Silvaco TCAD Tools Research Articles

Virtual Fabrication and Analog Performance of Sub-40nm Bulk MOSFET Using TCAD TOOL

Virtual Fabrication of sub-40nm Bulk MOSFET is carried out under channel engineering and source drain engineering process. These structures enable more aggressive device scaling in nano-scale region because of their ability to control short channel effects. How ever during scaling the junction depth should also be scaled down, which increases parasitic resistance so silicidation technique has been applied to reduce their effects on device. Analog performance has been measured in terms of gm, gds ,Av ,fT and fmax .The simulation result predict that gm is 3.75ms for engineered MOSFET as compared to nonengineered MOSFET with gm of 2.9ms for similar gate length, similarly Av for engineered device is 17.5db and for non-engineered device is 6.96db,fT is 146GHz and for non-engineered fT is 65GHz,fmax is 299GHz for engineered device and for nonengineered device fmaxis 170GHz and a comparison of an engineered device is done with a non engineered device to investigate the improved performance of an engineered device as compared to a non engineered device. Silvaco TCAD Tool is used for Virtual fabrication and simulation. ATHENA process simulator is used for virtual fabrication and ATLAS device simulator is used for device characterization.

Optimization of SiN x layer for solar cell using computational method

SiN x film grown by using the plasma-enhanced chemical-vapor deposition is most-widely used for the conventional crystalline silicon solar cell as an anti-reflection layer and also passivates the surface and the bulk of the silicon wafer. To minimize the reflection loss and increase the efficiency of the solar cell, the thickness and the refractive index of the SiN x film is generally determined by analyzing the surface reflectance of the SiN x layer on the silicon wafer. On the other hand, we optimized the thickness and the refractive index of the SiN x layer by confirming the efficiency of the solar cell prior to the real manufacturing process of the cell. In this work, Silvaco TCAD tool was used to design the conventional solar cell and the thickness and the refractive index of the SiN x film were varied in the range between 50 – 90 nm and 1.8–2.2, respectively. The optimum values of the thickness and the refractive index of the SiN x layer on the non-textured silicon wafer were 70 nm and 2.0, which are somewhat different from those determined from the analytical calculation of the reflectance only. Also, Silvaco TCAD tool was used to investigate the passivation process of the hydrogenated SiN x film. Through the simulation of the hydrogen diffusion, reduction of the recombination rate of the photo-generated electron-hole pair in the cell was confirmed.

An integrated driving circuit implemented with p-type LTPS TFTs for AMOLED

Based on the technology of low temperature poly silicon thin film transistors (poly-Si-TFTs), a novel p-type TFT AMOLED panel with self-scanned driving circuit is introduced in this paper. A shift register formed with novel p-type TFTs is proposed to realize the gate driver. A flip-latch cooperated with the shift register is designed to conduct the data writing. In order to verify the validity of the proposed design, the circuits are simulated with SILVACO TCAD tools, using the MODEL in which the parameters of LTPS TFTs were extracted from the LTPS TFTs made in our lab. The simulation results indicate that the circuit can fulfill the driving function.

Zero‐temperature‐coefficient biasing point of a fully‐depleted SOI MOSFET

AbstractThe gate characteristics (ID–VGS) of fully depleted, lightly doped, enhanced SOI n‐MOSFET are simulated over a wide range of operating temperature (300–600 K) by using the SILVACO TCAD tools. Simulation results show that there exists a biasing point where the drain current and the transconductance are temperature independent. Such a point is known as the zero‐temperature coefficient (ZTC) bias point. The drain‐current ZTC points are identified in both the linear and saturation regions. The transconductance ZTC exists only in the saturation region. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 366–370, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10920