Laser Voltage Imaging: A New Perspective of Laser Voltage Probing

Abstract

Laser Voltage Imaging (LVI) is a new application developed from Laser Voltage Probing (LVP). Most LVP applications have focused on design debug or design characterization, and are seldom used for global functional failure analysis. LVI enables the failure analysis engineer to utilize laser probing techniques in the failure analysis realm. In this paper, we present LVI as an emerging FA technique. We will discuss setting up an LVI acquisition and present its current challenges. Finally, we will present an LVI application in the form of a case study.

Preliminary Study on Detecting the Internal Voltage Values of Integrated Circuits Based on Electro-Optical Frequency Mapping

“…The photodiode was plugged into the spectrum analyzer to analyze the characteristics of the frequency domain signal from the DUT. The spectrum analyzer received the modulated electrical signal and output the EOFM signal strength at the frequency of interest [17]. The stepper motor controller controlled the XYZ translation stage to move the DUT.…”

“…These phase modulations of the reflected light can be converted into amplitude modulations by interferometric effects. EOFM uses a high-sensitivity photodetector to detect the amplitude modulation of the reflected light in the parts-per-million range, thereby locating the position of the transistor operating at the frequency of interest [12,16,17]. The 1319 nm laser wavelength is widely used in the EOFM, and the main effect of this wavelength is the free carrier effect [11].…”