| Description |
Solid state devices of all material systems exhibit inherent noise, i.e., random fluctuation in voltage or current, which by having the possibility of drowning the signal set a limit to their ultimate performance. Noise in solid state devices appears in a variety of forms and characteristics, including thermal noise, shot noise, generation-recombination noise, and 1/f noise. Despite the certainty attained over the years on the origin of the first three types of noise sources, the origin of 1/f noise still remains as a controversial matter. Although numerous fluctuations with 1/f spectral density have been observed in a variety of electronic devices and physical systems, qualitative understanding of the origins of these fluctuations is lacking. Despite the ambiguity on the origins of 1/f noise, understanding the physical origins and mechanisms involved in these random fluctuations is the key to improve the device performance. For the special case of MODFETs, despite their excellent high-frequency noise performance, in many nonlinear applications such as in mixers and oscillators, low frequency noise acts as a limiting factor. Ordinarily, for these devices the observed low frequency noise either consists of a pure1/f noise (with a frequency exponent close to one) or one or several generation-recombination noise bulges, due to traps, submerged in a 1/f noise.
In this project, we will engage in designing a measurement setup for automatic measurement and recording of 1/f noise of transistors between 100 mHz and 100 kHz. The major equipment in this setup is a dynamic signal analyzer (i.e. HP3561). Devising a proper interface between the dynamic signal analyzer and a PC through GPIB comprises the programming part of this project. Upon successful implementation of the interface, characterization and analysis of drain and gate low frequency noise of a GaN field effect transistor will be performed.
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