Alberto Porzio

Experimental and numerical investigation about SEB/SEGR of power MOSFET

We present a 3-D simulation analysis related to an experimental study which clarifies the role played by the parasitic BJT activation on the interaction between generated charge and electric field during ion impact in SEB/SEGR of power MOSFET. This activation is caused by the movement of the holes deposited during the ion impact and gives rise to a huge amount of charge that is sustained by avalanche multiplication. During SEGR phenomena this generated charge interact with the high electric field that is formed underneath the gate oxide thus causing damages to it. During SEB phenomena the generated charge causes a double injection phenomenon to take place that induces an electrical instability and, then, the MOSFET destruction.

Power supply distribution system for calorimeters at the LHC beyond the nominal luminosity

This paper investigates the use of switching converters for the power supply distribution to calorimeters in the ATLAS experiment when the Large Hadron Collider (LHC) will be upgraded beyond the nominal luminosity. Due to the highly hostile environment the converters must operate in, all the main aspects are considered in the investigation, from the selection of the switching converter topologies to the thermal analysis of components and PCBs, with attention to reliability issues of power devices subject to ionizing radiations. The analysis focuses on the particular, but crucial, case of the power supplies for calorimeters, though several outcomes of the research can profitably be applied to other detectors like muon chambers.

Experimental study and numerical investigation on the formation of single event gate damages induced on medium voltage power MOSFET

In this paper we present an experimental study aimed to identify the test conditions at which latent damages are created for different ion species with different energy losses both in the oxide and in the silicon. Moreover, with the help of 3-D finite element simulation, we give an interpretation for explaining the role played by the charge generated during the ion strike in starting the creation of the latent damage and in defining its amount.

Experimental evidence of “latent gate oxide damages” in medium voltage power MOSFET as a result of heavy ions exposure

Abstract The results presented in this paper are related to an experimental study that has the aim to evidence the formation of “latent gate oxide damages” in medium voltage power MOSFETs during the impact with energetic particles. The understanding of these “latent defectiveness” can be an helpful aid in the comprehension of the mechanisms of breach of the oxide layer of MOS structures induced by single energetic particles impact (single event gate rupture). To properly detect the presence of “latent damages” we have developed a high resolution experimental set-up and identified an appropriate region in which the device have to be biased in order to trigger this kind of damage.

A 3-D simulation study about Single Event Gate damage in medium voltage power MOSFET

In this paper we present a 3-D simulation study, based on experimental observation, which describes the role played by the strong increase of the electric field in the occurrence of gate damages induced by an heavy ion impact on typical medium power MOSFET devices.

Experimental and 3D Simulation Study on the Role of the Parasitic BJT Activation in SEB/SEGR of Power MOSFET

We present a 3-D simulation study, supported by experimental results, which clarifies the role played by the parasitic BJT activation on the interaction between generated charge and electric field during ion impact in SEB/SEGR of power MOSFET. This activation is caused by the movement of the holes deposited during the ion impact and gives rise to a huge amount of charge that is sustained by avalanche multiplication. During SEGR phenomena this generated charge interact with the high electric field that is formed underneath the gate oxide thus causing damages to it. Whereas during SEB phenomena the generated charge causes a double injection phenomenon to take place that induces an electrical instability and, then, the MOSFET destruction.

The role of the charge generated during heavy ion irradiation in the gate damage of medium voltage power MOSFET

An experimental study aimed to identify the test conditions at which latent damages are created is presented for different ion species with different energy losses both in the oxide and in the silicon. The experimental results, interpreted with the help of 3D finite element simulations, clarify the role played by the charge generated during the ion strike in starting the creation of latent damage. It is shown that a significant role is played by the charge generated in the oxide and at the silicon interface.

Induced damages in power MOSFETS after heavy ions irradiation

The usage of power MOSFETs in a hostile radiation environment, such as outer space and high energy physics experiments, is subordinated to their ability to tolerate the mechanisms initiated by the passage of energetic ions through the active volumes of the device. In this paper, we briefly present the main results obtained during our continuative study into the reliability of power MOSFETs during heavy ion impacts.