Masaya Iwamoto

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A non-quasi static large-signal FET model is presented incorporating self-heating and other multiple timescale dynamics necessary to describe the large-signal behavior of III–V FET technologies including GaAs and GaN. The model is unique in that it incorporates electro-thermal and trapping dynamics (gate lag and drain lag) into both the model current(More)
The relationships between X-parameters of a given transistor and a second transistor geometrically scaled with respect to the first are derived and presented for the first time. The different types of X-parameters scale differently. These relationships enable X-parameters measured on a fixed size of transistor, diode, or other similar test structure to be(More)
This paper reviews three modern transistor modeling flows enabled by large-signal waveform and/or X-parameter<sup>1</sup> measurements from a commercially available nonlinear vector network analyzer (NVNA) instrument. NVNA transistor characterization more safely exercises the device over a wider operating domain than is possible with conventional DC and(More)
This paper reviews and contrasts two complementary device modeling approaches based on data readily obtainable from a nonlinear vector network analyzer (NVNA) [1]. The first approach extends the application of waveform data to improve the characterization, parameter extraction, and validation methodologies for &#x201C;compact&#x201D; transistor models. NVNA(More)
High-frequency distortion in bipolar transistors is examined by using the charge-control approach of Poon and Narayanan to connect the device’s distortion behavior to its “loaded” unity–current–gain frequency (^ ). The resulting expressions for the distortion reveal considerable information on its frequency and bias dependence. Points on the ^ versus(More)
A knowledge-based neural network (KBNN) modeling and analysis method is presented for determining junction temperature, Tj, and thermal resistance, Rth, from simple electrical measurements of HBTs. The method retains sound physical principles of classical approaches but provides significant additional practical benefits for modeling and prediction based on(More)
  • Masaya Iwamoto, Craig P. Hutchinson, Beatrix Luk, T. S. Low, Donald C. D'Avanzo
  • 2017 IEEE Compound Semiconductor Integrated…
  • 2017
Spurious oscillations in the low frequency region (below 100kHz) were investigated in InGaP/GaAs HBT devices and circuits. These low frequency oscillations (LFOs) are predominantly activated by the field across the semi-insulating GaAs substrate located between the subcollector and backside metal (of an emitter-up device). Several experiments were conducted(More)
BACKGROUND This study examined whether targeted disruption of the genes for the prostacyclin receptor (IP) or the thromboxane A2 receptor (TP) confers a susceptibility to salt-dependent hypertension. METHODS AND RESULTS Eight female IP- or TP-deficient mice were examined. Baseline systolic blood pressure (SBP) did not differ between TP(-/-) and TP(+/+),(More)
A formulation and implementation of the III&#x2013;V FET nonlinear charge model decomposed into a combination of univariate voltage depletion charges and a bivariate mixed voltage-current dependent &#x201C;drift&#x201D; charge is presented. The concept is based on the principles used in well-established BJT models where depletion and diffusion charges are(More)
BACKGROUND AND AIM Fas-associated phosphatase-1 (FAP-1) has been thought as an inhibitor in Fas-mediated apoptosis. Here, we investigated the role of FAP-1 in Fas-mediated apoptosis of human colon cancer cells. METHOD The viability of four colon cancer cell lines treated with agonistic anti-Fas antibody was determined using WST-1 assay and cell death(More)