When you run a long simulation time analysis the evaluated time points are normally all held in memory until the end time is reached. All the data is then written out to the output rawfile. This means a large amount of system memory can be used up and also has to be tracked. If in the input deck the line “.OPTIONS RAWPTS=300 POST” is included then as soon as the maximum number of points is reached given by “RAWPTS=300” then all the vector data is saved to the raw data output file and the memory is free to be re-used. In this way the output rawfile is incrementally increased in size every time this limit is reached. The memory required by the simulation run is therefore reduced, and with less memory to manage, the simulation is run faster. This is particularly useful on the PC platform where some of the memory is required for the operating system and RAM size is less than 1GB.

Silvaco’s Guardian LVS tool compares two circuits that are defined by their netlists. The comparison is based strictly on the topological structure of these circuits. Topologically equivalent netlists are considered different, even if they are functionally equivalent. There are several techniques available for designing the same functionality by means of topologically different netlists. While it is impossible for the LVS tool to “know” about all these techniques, many are supported.

Recent years has seen rapid acceleration in the research and development of organic thin film transistors (OTFTs) as key components for active matrix displays, radio frequency identification tags, and many other small scale integrated circuits. There are many advantages to OTFTs, such as the flexibility of the plastic fabrication substrate and the potential cost savings to manufacturers that adopt a solution process and/or ink-jet printing process.

This article addresses the creation of semiconductor laser double heterostructures, and the subsequent simulation of laser output with DevEdit from Silvaco. A laser consists of a gain medium sandwiched between two mirrors forming the laser cavity. This is necessary for effective laser operation because the round trip gain of the device, including the material and mirror losses, is unity. In addition, there is an integer number of half-wavelengths of light inside the optical length of the laser cavity.

ATHENA’s Optolith module is designed to simulate the 3 basic lithography technologies; contact printing, proximity and projection lithography. The imaging calculations within Optolith are flexible enough to handle all three situations. Optolith is based upon a solution of the Helmholtz equation for media with complex refractive indices and the Beam Propogation Method [1]. This allows Optolith to take account of both diffraction effects and any non-linear local optical properties of the resist material.