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A compact large-signal model, called Compact Carbon Nanotube Model (CCAM), is presented that accurately describes the shape of DC and small-signal characteristics of fabricated carbon nano-tube FETs (CNTFETs). The new model consists of computationally efficient and smooth current and charge formulations. The model allows, for a given gate length, geometry scaling from single-finger single-tube to multifinger multitube transistors. Ambipolar transport, temperature dependence with self-heating, noise, and a simple trap model have also been included. The new model shows excellent agreement with the data from both the Boltzmann transport equation and measurements of Schottky-barrier CNTFETs and has been implemented in Verilog-A, making it widely available across circuit simulators. [ABSTRACT FROM PUBLISHER]

A set of minority charge and transit time expressions is derived as an alternative to the transit time model used in the SPICE Gummel-Poon model (SGPM), which is inadequate for the reliable design of circuits running either at low voltages or high current densities. The newly derived equations are physics-based and laterally scalable as well as appropriate for integration into compact models. Experimental results of the new model are described in terms of transit time, geometry and transit time versus bias, and temperature.

A systematic method for the integration of correlated shot-noise sources into compact models (CMs) is presented, which significantly improves the accuracy of predicted high-frequency noise in transistors. The developed method relies on a system theory approach, and hence, is not limited to specific CM or device type. In this paper, the method is applied to the CM HICUM, which serves a vehicle for verification purposes. The method and its implementation were verified for SiGe heterojunction bipolar transistors based on measured data for frequencies up to 50 GHz, as well as on device simulation data up to 500 GHz, obtained from simulations of both hydrodynamic and a Boltzmann transport model. [ABSTRACT FROM PUBLISHER]

Presents several abstracts of articles on integrated circuits solicited from presentations at the 2001 Bipolar/BiCMOS Circuit and Technology Meeting in Minneapolis, Minnesota.

Purpose: We aimed to determine the surgical indications and postoperative outcomes among pediatric patients with lobar cerebral cavernous malformations (CCMs)., Methods: We retrospectively reviewed pediatric patients operated on for lobar CCM between March 2010 and August 2021. Indications for surgery included (1) intracranial hemorrhage, (2) symptomatic superficially located lesion, and (3) asymptomatic CCM in non-eloquent area in case of strong parental preferences. Patients presenting with seizures were assessed using Engel Epilepsy Surgery Outcome Scale., Results: Twenty-one patients were included. The predominant symptoms were seizures (57.1%), headaches (33.3%), and focal neurological deficits (23.8%). Patients were qualified for surgery due to symptomatic intracranial hemorrhage (47.6%), drug-resistant epilepsy (28.6%), and focal neurological deficits (9.5%). Three patients (14.3%) were asymptomatic. A gross total resection of CCM with the surrounding hemosiderin rim was achieved in all patients. The mean follow-up was 52 months. No patient experienced surgery-related complications. In all individuals with a preoperative first episode of seizures or focal neurological deficits, the symptoms subsided. All six patients with drug-resistant epilepsy improved to Engel classes I (67%) and II (33%)., Conclusion: Surgical removal of symptomatic lobar CCMs in properly selected candidates remains a safe option. Parental preferences may be considered a sole qualifying criterion for asymptomatic lobar CCM excision., (© 2024. The Author(s).)