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We observe rich phenomena of two-level random telegraph noise (RTN) from a commercial bulk 28-nm p-MOSFET (PMOS) near threshold at 14 K, where a Coulomb blockade (CB) hump arises from a quantum dot (QD) formed in the channel. Minimum RTN is observed at the CB hump where the high-current RTN level dramatically switches to the low-current level. The gate-voltage dependence of the RTN amplitude and power spectral density match well with the transconductance from the DC transfer curve in the CB hump region. Our work unequivocally captures these QD transport signatures in both current and noise, revealing quantum confinement effects in commercial short-channel PMOS even at 14 K, over 100 times higher than the typical dilution refrigerator temperatures of QD experiments (< 100 mK). We envision that our reported RTN characteristics rooted from the QD and a defect trap would be more prominent for smaller technology nodes, where the quantum effect should be carefully examined in cryogenic CMOS circuit designs. [ABSTRACT FROM AUTHOR]

This article proposes a new approach for modeling self-heating in gallium nitride (GaN) high-electron-mobility transistors (HEMTs). The proposed approach utilizes two heat sources to model the effects of the relatively uniform heat generation when the device is in the linear regime and the concentrated heat generation in the high-field area after the device pinches off. Compared to traditional single heat source modeling approaches, the proposed approach yields a model that can accurately capture the bias dependence of the heat and temperature distribution in the GaN HEMT channel without resorting to the more resource-intensive electrothermal simulations. It also leads to a simple yet accurate analytical expression for the maximum channel temperature using thermal resistances that have clear geometric dependence. [ABSTRACT FROM AUTHOR]

In this paper, we study the self-heating mechanism and its impact on electrical performance of short gate length GaN high electron mobility transistors (HEMTs) based on electrothermal TCAD simulations. We propose an equivalent channel temperature to quantify the current degradation due to self-heating and also resolve the discrepancies between temperature measurements through electrical methods and thermal methods in the literature. We then explain the equivalent channel temperature’s behavior using the temperature- and field-dependent electron transport theory for short gate length HEMTs. The implications and guidelines to the various aspects of device design are also discussed. [ABSTRACT FROM AUTHOR]

This paper extends the noise theory of linear networks to enable direct deembedding of noise factors for an active device surrounded by a passive four-port. It solves the problem of noise factor deembedding, when there are feedback paths between the output and input of a device-under-test. It also leads to a new approach to obtain intrinsic noise parameters for on-wafer noise measurements by performing deembedding first and optimization last. Verification of the noise factor deembedding algorithm is performed using idealized data, and the evaluation of the new noise parameter deembedding approach is conducted using the experimental data of the n-type MOSFETs fabricated in 28- and 90-nm CMOS technology from United Microelectronics Corporation. [ABSTRACT FROM PUBLISHER]

This paper presents an improved z-parameter based approach to extract the gate resistance at low frequencies. The effectiveness of this approach, compared with other y-parameter based approaches, is verified using 430 samples fabricated in 40-, 55-, 90-, and 110-nm CMOS technology nodes. The influence of the nonquasi-static (NQS) effect, resulting from the distributed channel resistance, on the gate resistance extraction is studied, and the optimum processes are suggested to reduce the NQS effect. Finally, the extraction of the channel resistance in the lightly doped drain region is also presented. [ABSTRACT FROM PUBLISHER]