The proliferation of Internet-of-Things has promoted a wide variety of emerging applications that require compact, lightweight, and low-cost optical spectrometers. While substantial progresses have been made in the miniaturization of spectrometers, most of them are with a major focus on the technical side but tend to feature a lower technology readiness level for manufacturability. More importantly, in spite of the advancement in miniaturized spectrometers, their performance and the metrics of real-life applications have seldomly been connected but are highly important. This review paper shows the market trend for chip-scale spectrometers and analyzes the key metrics that are required to adopt miniaturized spectrometers in real-life applications. Recent progress addressing the challenges of miniaturization of spectrometers is summarized, paying a special attention to the CMOS-compatible fabrication platform that shows a clear pathway to massive production. Insights for ways forward are also presented.

A multi-point self-coupling waveguide spectral shaper for on-chip computational spectrometer is proposed and verified by simulation. The autocorrelation coefficient of the spectral response of the filter has very narrow width of the main lobe, which helps to achieve a high resolution of the spectrometer. Due to the rich design degrees of freedom, each filter with can be designed to exhibit very distinct spectral characteristics, so that only 30 channels are adequate for accurate spectral reconstruction with 100 nm bandwidth and 2.5 nm resolution. Each filter has an ultra-compact footprint less than 4550.4 µm 2 and 30 filters in total occupy a footprint of about 0.13 mm 2 .

We demonstrate a silicon single-shot spectrometer with 0.008mm2 footprint, the smallest on CMOS compatible platforms. Experimental results confirm a bandwidth of 180nm with a resolution of 0.45nm. It opens new pathway towards commercial integrated spectrometers.

With the development of semiconductor technology and the increment quantity of metal layers in past few years, backside EFA (Electrical Failure Analysis) technology has become the dominant method. In this paper, abnormally high Signal Noise Ratio (SNR) signal captured by Electro-Optical Probing (EOP)/Laser Voltage Probing (LVP) from backside is shown and the cause of these phenomena are studied. Based on the real case collection, two kinds of failure mode are summarized, and simulated experiments are performed. The results indicate that when a current path from power to ground is formed, the high SNR signal can be captured at the transistor which was on this current path. It is helpful of this consequence for FA to identify the failure mode by high SNR signal.