Entries by Erick Castellon
3D TFT Simulation of Grains and Grain Boundaries
Introduction
Low-temperature polycrystalline silicon (LTPS) thin-film transistors have been widely applied to AMOLED (Active Matrix Organic Light Emitting Diode) as the most suitable means for high mobility, high switching speed and high resolution [1-2].
A Laser Annealing Process such as Excimer Laser Annealing (ELA) is used to manufacture by converting Amorphous Silicon (a-Si) to Polycrystalline Silicon (poly-Si) at low temperature. The poly-Si structure (produced through ELA) shows the laser wavelength, pulse width and spatial beam dependencies.
Quantum Dot-Based Hybrid Light Emitting Diode Modelling Using Radiant
Introduction
With the recently launched Radiant, a graphical user interface (GUI) for Atlas-based TCAD simulations, the entry barrier for inexperienced users has been lowered. In particular, the use of guided simulation tools, for both experienced and novice researchers, can speed up the development cycle. Light emitting diodes (LEDs) have caught the attention of the scientific community for many years, especially organic-based light emitting diodes (OLEDs) and the emerging quantum dot-based light emitting diodes (QD-LEDs).
Verification of an Compact Model for Organic Thin-Film-Transistors by Using MixedMode Creating an CMOS Inverter Circuit with TCAD Transistor Devices
Organic thin-film transistors (OTFTs) are promising devices for future low-cost electronics[1][2]. However, to enable the development of this technology, circuit design simulation is needed. TCAD with MixedMode approach provides a suitable route for the physics based simulation of these transistors within simple circuits. As circuits become more complicated, more devices are needed and the computing time increases significantly. Compact models describe the behavior of the device with only a few equations and thus the computing time is reduced to a viable magnitude. Such equations are written down in a Verilog-A format which can be used by most SPICE simulators.
Hints, Tips and Solutions – Movie and PDF Report Generation with the DeckBuild GUI
Introduction
In this article we will emphasize two new features of the DeckBuild deck editing environment. These are the movie creation on the one hand and the creation of PDF reports on the other. The latest version of DeckBuild allows you to use recorded history points to prepare movies and PDF reports of a simulation flow. We will start by first illustrating the basic history creation and script execution mechanism, followed by pointing out the creation of movies. After that, we will demonstrate how to create a customized PDF report out of your simulation flow.
Ballistic Quantum Transport in Nanoscale Transistors: a Non Equilibrium Green’s Function Approach
Introduction
As MOS field-effect transistors are scaled down to a nanometer regime, quantum effects in both transverse and transport directions start playing a major role in determining device characteristics. In order to address a new challenge, SILVACO has started a deployment of new quantum mechanical models based on Non Equilibrium Green’s Function (NEGF) approach. This is a fully quantum mechanical approach which treats such effects as source-to-drain tunneling, ballistic transport, and quantum confinement on equal footing. The new NEGF solver is suitable to model ballistic quantum transport in such devices as Double Gate or Surround Gate MOSFET, using rectangular or cylindrical geometries in ATLAS. The method used is based on references [1] and [2].
A Novel Approach to Three-Dimensional Semiconductor Process Simulation: Application to Thermal Oxidation
Abstract
The paper presents a new approach to three-dimensional semiconductor process simulation that overcomes the problem of moving boundaries and mesh generation. Contrary to using unstructured meshes, the approach makes use of the level set method on fixed Cartesian meshes. A concept of multi-layer structure is introduced to capture an arbitrary complex structure. To handle a big geometrical scale ratio in a structure, the concept of adaptive mesh refinement is used. A special in-house finite-difference scheme is designed to approximate the relevant equations near material interfaces. In the bulk of regular nodes the standard finite difference schemes are used. Application of the approach to the modeling of oxidation of some typical types of structures used in semiconductor technology is demonstrated.
Simulation of an Organic Photovoltaic Cell (OPC) Using Atlas
Introduction
In recent years, the investigation of Organic Light Emitting Diodes (OLEDs) and photovoltaic devices based on small organic molecules and polymers has attracted significant interest due to their potential for inexpensively generated electricity. ATLAS has been used already to investigate OLEDs [1] and compound material GaInP[2][3] devices.
Two-Dimensional Atlas Device Simulation of an Organic Light-Emitting Field-Effect Transistor Using a Heterostructure Inside the Transistor Channel
1. Introduction
Organic semiconductors have been incorporated in a wide range of devices, including organic thin-film transistors (OTFTs) and circuits, organic solar cells, organic non-volatile memories and organic light-emitting diodes (OLEDs). Display applications are a particularly important driver for the further development of this organic technology.
Electrical Stress Degradation of Small-Grain Polysilicon Thin-Film Transistors
Abstract
This paper is focused on the stability of n-channel laser-crystallized polysilicon thin-film transistors (TFTs) submitted to a hydrogenation process during the fabrication and with small grains dimension. With the aid of numerical simulations, we investigate the effects of static stress using two types of procedures: the on stress and the hot carrier stress. Results show that the variations of trap state density into the whole polysilicon layer and not only near the drain junction are responsible for the degradation of TFTs performances in both the two types of stress and that the interface trap states play a negligible role compared to the bulk trap states.