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Abstract: Light emission technique is well known to observe photon emission produced by transistor activity or by biased junctions. Constant progresses on InGaAs camera have driven low noise and high quantum efficiency. In this paper we show how these improvements give to InGaAs Infrared (IR) detector the ability to catch thermal activity coming from heating point of an integrated circuit (IC). We demonstrate the advantage of photon counting for these very low thermal emission fluxes. Experiments have been done with a specific Multi-Channel Plate (MCP) detector able to count position and date each photon incoming on detector field of view. We also demonstrate how the sub-nanosecond timing resolution open the door to thermal analysis at high magnification and high speed through a specific data treatment for Ultra Fast Thermal Propagation Analysis (UFTPA). [Copyright &y& Elsevier]

Abstract: The mixed-mode ICs (Integrated Circuits), by involving multiple functions (digital, analog, RF, power) inside one device, are becoming more compact and useful. At the same time, their developments and Failure Analysis (FA) are more and more complex: test, diagnostic and defect localization steps are harder and longer in time. Each step needs to be improved as far as defect localization is concerned. Several techniques based on emission microscopy, electron beam, direct probing or laser stimulation have been developed and introduced to follow these ICs evolutions. The most recent evolution in the laser stimulation field has been the introduction of several dynamic laser stimulation techniques aimed to localize defects or weakness regions inside functional but failing ICs (environmental marginalities related to temperature, frequency, voltage, etc.). This paper deals with the use of dynamic photoelectric laser stimulation techniques applied on mixed-mode ICs where the major difficulty is due to their considerable intrinsic sensitivity. Indeed, the analog circuitry is more sensitive than the digital circuitry since a slight change in an electrical parameter can trigger a functionality failure. This property limits the defect localization because of the complex interpretation of the results, the laser stimulation mapping. We propose to help the failure analyst by coupling the dynamic laser stimulation mapping with the photoelectric impact simulations run on a previously analyzed structure. The goal is to predict and interpret the laser sensitivity mapping so to isolate the defective areas in the analog devices. [Copyright &y& Elsevier]

Abstract: Thermal time constant analysis (TTC) opens a wide range of applications: structure identification, 3D localization for very deep micron technologies. In this paper, we describe a new analysis methodology for TTC signatures induced by modulated thermal laser stimulation (TLS). Previous approaches did not allow a fast and rigorous method to acquire and treat transient TLS signals. To overcome these limitations we have done a theoretical study, based on the Fourier transform of an analytical model describing temporal dependency of the TLS signal, which is powerful for signature interpretation. This analysis flow is applied to 65nm reliability test structure. [Copyright &y& Elsevier]

Abstract: The study is carried out on AlGaN/GaN HEMTs presenting current collapse effect at V ds lower than 6V. This effect is completely recovered by illuminating the component with light of 710nm wavelength (1.75eV). The spectral analysis of the light emission in the visible near infrared spectrum shows a bell-shape with superimposed distinct emission peaks. These features suggest that the electroluminescence (EL) signal is due to the direct intraband of electrons and inelastic intraband transition of electrons due to scattering by charged centres. Photoionisation experiments have been conducted to determine the light wavelengths/energies that separately change the drain current and the gate leakage current. [Copyright &y& Elsevier]

Abstract: This paper presents an improvement of the time resolution of the Photoelectric Laser Stimulation technique using the phase of a mode-locked laser as a reference to generate an electrical stimulus for the device under test. This synchronization system was applied to observe signal propagation in an 860 MHz ring oscillator. [Copyright &y& Elsevier]

Abstract: Dynamic Laser Stimulation (DLS) is an important technique for IC analysis and timing characterization. Implementations and practical considerations are presented for SDL, RIL and LADA techniques as well as the latest methodology know as Delay Variation Mapping (DVM). Downside of dynamic laser techniques is higher complexity of IC setup and results interpretation. Understanding these aspects is necessary to benefit from DLS for the IC analysis and timing characterization. [Copyright &y& Elsevier]