TCAD mixed-mode simulation of bitflip with pulsed laser

Abstract

Simulation of pulsed laser single event effects (SEE) is not considered in most of the well known software packages for mixed-mode simulation of SEE. This paper shows an adaptation of the Sentaurus TCAD suite to pulsed laser SEE simulation. After the literature review, we present the virtual model of the target transistor, calibrated against a real transistor of an specific ASIC. That virtual model is used to evaluate the Linear Energy Transfer (LET) threshold for bitflip in a simulated flip-flop circuit using the heavy-ion simulation tools of TCAD. That simulations help us to make an adaptation of Sentaurus TCAD for simulation of pulsed laser experiments. The pulsed laser simulation results are compared with a laser pulse experiment, showing that the proposed model achieves more accuracy than previous models referred to in the literature.

Determination of IC Age through Laser Irradiation

“…The difference increases with aging, such that (E ′ f resh ) 0.9V − (E ′ f resh ) 0.7V = 100 pJ, whereas (E ′ 52mV ) 0.9V − (E ′ 52mV ) 0.7V = 160 pJ, thus highlighting the impact of voltage scaling with increasing ∆V th . Laser irradiation represented by a Gaussian beam, in terms of essential parameters such as spot size and beam radius 26 . The confocal length extends between point A, where beam is the narrowest, and point B, where area of the beam is twice that at A.…”

“…12-16 below. Thus, by establishing equivalency between the terms, HIM is successfully adapted for photon irradiation analysis 26 .…”

“…5) is used in keeping with the lowest practically attainable spot size of a laser beam 29 . A laser pulse duration of 120 fs is selected as a suitable parameter, considering the "the temporal scale of the passage of particle along the sensitive length in Si device (around 2-3 µm)" 26 . An LET of 8.83 × 10 11 pairs/cm 3 is calculated at 0.065 µm, which is the entire distance that light travels within the device.…”

“…An LET of 8.83 × 10 11 pairs/cm 3 is calculated at 0.065 µm, which is the entire distance that light travels within the device. T trans of 8.12% is chosen by accounting for metal layers that would impede full transmission of incident radiation 26 . The drain of each transistor (M1-M4) is irradiated, as shown in Fig.…”

“…Figure 11.Laser irradiation represented by a Gaussian beam, in terms of essential parameters such as spot size and beam radius26 . The confocal length extends between point A, where beam is the narrowest, and point B, where area of the beam is twice that at A.…”