Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Electronic Devices and Semiconductor Manufacturing

Selected Works

Mark Somerville

HEMT

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Degradation Uniformity Of Rf-Power Gaas Phemts Under Electrical Stress, Anita Villanueva, Jesus Del Alamo, Takayuki Hisaka, Kazuo Hayashi, Mark Somerville Jul 2012

Degradation Uniformity Of Rf-Power Gaas Phemts Under Electrical Stress, Anita Villanueva, Jesus Del Alamo, Takayuki Hisaka, Kazuo Hayashi, Mark Somerville

Mark Somerville

We have studied the electrical degradation of RF-power PHEMTs by means of in situ 2-D light-emission measurements. Electroluminescence originates in the recombination of holes that have been generated by impact ionization. The local light intensity, thus, maps the electric-field distribution at the drain side of the device. This allows us to probe the uniformity of electrical degradation due to electric-field-driven mechanisms. We find that electrical degradation proceeds in a highly nonuniform manner across the width of the device. In an initial phase, degradation takes place preferentially toward the center of the gate finger. In advanced stages of degradation, the edges …


Determining Dominant Breakdown Mechanisms In Inp Hemts, Mark Somerville, Chris Putnam, Jesus Del Alamo Jul 2012

Determining Dominant Breakdown Mechanisms In Inp Hemts, Mark Somerville, Chris Putnam, Jesus Del Alamo

Mark Somerville

We present a new technique for determining the dominant breakdown mechanism in InAlAs-InGaAs high-electron mobility transistors. By exploiting both the temperature dependence and the bias dependence of different physical mechanisms, we are able to discriminate impact ionization gate current from tunneling and thermionic field emission gate current in these devices. Our results suggest that the doping level of the supply layers plays a key role in determining the relative importance of these two effects.