Olivier Gagliano

Building the electrical model of the pulsed photoelectric laser stimulation of an NMOS transistor in 90nm technology

This paper presents measurements of pulsed photoelectrical laser stimulation of an NMOS transistor in 90nm technology. The laser power was able to trig the NPN parasitic bipolar Drain/Psubstrate/Source. An electrical model is proposed in order to simulate effects induced by the laser. Results extracted from the electrical simulator are compared to measurements.

Robustness improvement of an SRAM cell against laser-induced fault injection

This paper presents the design of an SRAM cell with a robustness improvement against laser-induced fault injection. We report the fault sensitivity mapping of a first SRAM design. A careful analysis of its results combined with the use of an electrical model at transistor level of the photoelectric effect induced by a laser permit us to validate our approach. The robustness improvement is due to a specific layout which takes into account the topology of the cell and to the effect of a triple well implant on the laser sensitivity of NMOS transistors.

Building the electrical model of the pulsed photoelectric laser stimulation of a PMOS transistor in 90nm technology

This paper presents measurements of pulsed photoelectrical laser stimulation of a PMOS transistor in 90 nm technology. The laser power was able to trig three PNP parasitic bipolar transistors Drain/Nwell/Source, Drain/Nwell/Psubstrate and Source/Nwell/Psubstrate. An electrical model is proposed in order to simulate effects induced by the laser. Results extracted from the electrical simulator are compared to measurements.

Characterization and TCAD simulation of 90 nm technology transistors under continous photoelectric laser stimulation for failure analysis improvement

This study is driven by the need to optimize failure analysis methodologies based on laser/silicon interactions, using the functional response of an integrated circuit to local laser stimulation. It is therefore mandatory to understand the behavior of elementary devices to laser illumination, in order to model and predict the behavior of more complex circuits. This paper characterizes and analyses photoelectric effects induced by static 1064 nm wavelength laser on a 90 nm technology NMOS transistor. Comparisons between photocurrents in short or long channel transistor, or in function of its state (on or off) are presented. Experimental measurements are correlated to Finite Elements Modeling Technology Computer Aided Design (TCAD) analyses, which gives a physical insight of carriers generation and transport in the devices.

Finite element method as applied to the study of gratings embedded in complementary metal-oxide semiconductor image sensors

We present a new formulation of the finite element method (FEM) dedicated to the rigorous solution of Maxwells equations and adapted to the calculation of the scalar diffracted field in optoelectronic subwavelength periodic structures [for both transverse electric (TE) and transverse magnetic (TM) polarization cases]. The advantage of this method is that its implementation remains independent of the number of layers in the structure, the number of diffractive patterns, the geometry of the diffractive object, and the properties of materials. The spectral response of large test photodiodes that can legitimately be represented in 2-D has been measured on a dedicated optical bench and compared to the theory. The validity of the model as well as the possibility of conceiving in this way simple processible diffractive spectral filters are discussed.

The Finite Element Method as applied to the calculation of the quantum efficiency in optoelectronic imaging devices

We present a new formulation of the Finite Element Method (FEM) dedicated to the 2D rigorous solving of Maxwell equations adapted to the calculation of the diffracted field in optoelectronic subwavelength structures. The advantage of this method is that its implementation remains independent of the number of layers in the structure, of the number of diffractive patterns, of the geometry of the diffractive object and of the properties of the materials. The spectral response of large test photodiodes that can legitimately be represented in 2D has been measured on a dedicated optical bench and confronted to the theory. The representativeness of the model as well as the possibility of conceiving this way simply processable diffractive spectral filters are discussed.