Impact of plasma etching on the noise performance of Ti/ p -Si and Ti/p-Si1−xGex Schottky contacts

Asokan

Journal of Applied Physics

et al. 2012

1/f noise measurements were performed on Ni/n-GaN Schottky barrier diode under forward bias over a wide temperature range from 80 to 300 K. The noise spectra exhibited frequency dependence proportional to 1/f 0 with c varying between 0.8 and 1.1 down to 1 Hz. The spectral power density of current fluctuations, S I , was found to decrease with increase in temperature. Current-voltage (I-V) characteristics of the diodes have been measured, and metal-semiconductor interface was found to be spatially inhomogeneous in the temperature range 80-300 K. The decrease in 1/f noise with increase in temperature is explained within the framework of spatial inhomogeneities model. V C 2012 American Institute of Physics. [http://dx.

Section: Introductionmentioning

confidence: 99%

Temperature dependence of 1/f noise in Ni/n-GaN Schottky barrier diode

Asokan

Journal of Applied Physics

et al. 2012

Journal of Applied Physics

“…10 The noise power density S I at a frequency f then can be expressed for a given bias V and dc current I as 10…”

Section: Resultsmentioning

confidence: 99%

“…Lao's model attributed the 1/f noise to the mobility and diffusivity fluctuations of the carriers within the space charge region. 10 According to this model the noise power density should increase with the increase in temperature. However, in many cases we observe the reverse behavior, that is, decrease in noise with increase in temperature.…”

mentioning

confidence: 99%

Barrier height dependence of Fano factor and 1/f noise effect on InGaP based Schottky barrier diode

Mangal¹,

Ghelfi²,

Bogoni³

et al. 2011

We report a study on flicker noise reduction in the space charge limitation region of a Zn-Pd/ n-In 0.49 Ga 0.51 P Schottky barrier diode (SBD). A suitable model has been suggested to explain the barrier height dependence of the Fano factor. The reduction of Fano factor with barrier height has been experimentally investigated from I-V characteristics and noise power density measurements. Finally a comparative study was made with the theoretically obtained value of the Fano factor. Another important parameter, known as the Hooge parameter, of InGaP SBD has also been calculated as a function of temperature.

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

“…31,33 The factor ␥ H / N has been used to characterize plasma etching-induced sidewall damage. 31,33 The factor ␥ H / N has been used to characterize plasma etching-induced sidewall damage.…”

Section: Introductionmentioning

confidence: 99%

Sidewall damage in plasma etching of Si/SiGe heterostructures

Ding

Klein²,

Friesen

et al. 2009

Plasma etching is a critical tool in the fabrication of Si/SiGe heterostructure quantum devices, but it also presents challenges, including damage to etched feature sidewalls that affects device performance. Chemical and structural changes in device feature sidewalls associated with plasma-surface interactions are considered damage, as they affect band structure and electrical conduction in the active region of the device. Here the authors report the results of experiments designed to better understand the mechanisms of plasma-induced sidewall damage in modulation-doped Si/SiGe heterostructures containing a two-dimensional electron gas. Damage to straight wires fabricated in the heterostructure using plasma etching was characterized both by measuring the width of the nonconductive "sidewall depletion" region at the device sidewall and by measuring the noise level factor ␥ H / N determined from spectra of the low frequency noise. Observed increases in sidewall depletion width with increasing etch depth are tentatively attributed to the increase in total number of sidewall defects with increased plasma exposure time. Excess negative charge trapped on the feature sidewall could be another contributing factor. Defects at the bottom of etched features appear to contribute minimally. The noise level shows a minimum at an ion bombardment energy of ϳ100 eV, while the sidewall depletion width is independent of bias voltage, within experimental uncertainty. A proposed explanation of the noise trend involves two competing effects as ion energy increases: the increase in damage caused by each bombarding ion and the reduction in total number of incident ions due to shorter etch times.