Currently, the global 5G network, cloud computing, and data center industries are experiencing rapid development. The continuous growth of data center traffic has driven the vigorous progress in high-speed optical transceivers for optical interconnection within data centers. The electro-absorption modulated laser (EML), which is widely used in optical fiber communications, data centers, and high-speed data transmission systems, represents a high-performance photoelectric conversion device. Compared to traditional directly modulated lasers (DMLs), EMLs demonstrate lower frequency chirp and higher modulation bandwidth, enabling support for higher data rates and longer transmission distances. This article introduces the composition, working principles, manufacturing processes, and applications of EMLs. It reviews the progress on advanced indium phosphide (InP)-based EML devices from research institutions worldwide, while summarizing and comparing data transmission rates and key technical approaches across various studies.

The formation of an electric dipole at the high-k/SiO₂ interface is quantitatively analyzed. The band lineups and physical origin of dipole formation at the high-k/SiO₂ interface are explained by the dielectric contact induced gap states (DCIGS). The charge neutrality level (CNL) of the DCIGS, which represents a distribution of high-k and SiO₂ contact induced gap states, is utilized to study the dipole moment. The charge transfer due to different CNLs of high-k and SiO₂ is considered as the dominant origin of dipole formation. The theoretically calculated dipole strengths of high-k/SiO₂ systems based on this model are in good agreement with the experimental data.

The characteristics of TDDB (time-dependent dielectric breakdown) and SILC (stress-induced leakage current) for an ultra-thin SiO₂/HfO₂ gate dielectric stack are studied. The EOT (equivalent-oxide-thickness) of the gate stack (Si/SiO₂/HfO₂/TiN/TiAl/TiN/W) is 0.91 nm. The field acceleration factor (γ) extracted in TDDB experiments is 1.59 s·cm/MV, and the maximum voltage is 1.06 V when the devices operate at 125℃ for ten years. A detailed study on the defect generation mechanism induced by SILC is presented to deeply understand the breakdown behavior. The trap energy levels can be calculated by the SILC peaks:one SILC peak is most likely to be caused by the neutral oxygen vacancy (V_O) in the HfO₂ bulk layer at 0.51 eV below the Si conduction band minimum; another SILC peak is induced by the interface traps, which are aligned with the silicon conduction band edge. Furthermore, the great difference between the two SILC peaks demonstrates that the degeneration of the high-k layer dominates the breakdown behavior of the extremely thin gate dielectric.

In this paper, a high-gain inductorless LNA (low-noise amplifier) compatible with multiple communication protocols from 0.1 to 5.1 GHz is proposed. A composite resistor−capacitor feedback structure is employed to achieve a wide bandwidth matching range and good gain flatness. A second stage with a Darlington pair is used to increase the overall gain of the amplifier, while the gain of the first stage is reduced to reduce the overall noise. The amplifier is based on a 0.25 μm SiGe BiCMOS process, and thanks to the inductorless circuit structure, the core circuit area is only 0.03 mm². Test results show that the lowest noise figure (NF) in the operating band is 1.99 dB, the power gain reaches 29.7 dB, the S₁₁ and S₂₂ are less than −10 dB, the S₁₂ is less than −30 dB, the IIP3 is 0.81dBm, and the OP_1dB is 10.27 dBm. The operating current is 31.18 mA at 3.8 V supply.

The effects of the quantum well (QW) width, carrier density, and aluminium (Al) concentration in the barrier layers on the optical characteristics of a gallium nitride (GaN)-based QW laser diode are investigated by means of a careful modelling analysis in a wide range of temperatures. The device’s optical gain is calculated by using two different band energy models. The first is based on the simple band-to-band model that accounts for carrier transitions between the first levels of the conduction band and valence band, whereas the second assumes the perturbation theory (k.p model) for considering the valence intersubband transitions and the relative absorption losses in the QW. The results reveal that the optical gain increases with increasing the n-type doping density as well as the Al molar fraction of the Al_xGa_1–xN layers, which originate the GaN compressive-strained QW. In particular, a significant optical gain on the order of 5000 cm^–1 is calculated for a QW width of 40 Å at room temperature. In addition, the laser threshold current density is of few tens of A/cm² at low temperatures.

One of the core semiconductor devices is the electrostatic chuck. It has been widely used in plasma-based and vacuum-based semiconductor processing. The electrostatic chuck plays an important role in adsorbing and cooling/heating wafers, and has technical advantages on non-edge exclusion, high reliability, wafer planarity, particles reduction and so on. This article extracts key design elements from the existing knowledge and techniques of electrostatic chuck by the method proposed by Paul and Beitz, and establishes a design space systematically. The design space is composed of working objects, working principles and working structures. The working objects involve electrostatic chuck components and materials, classifications, and relevant properties; the working principles involve clamping force, residual force, and temperature control; the working structures describe how to compose an electrostatic chuck and to fulfill the overall functions. The systematic design space exhibits the main issues during electrostatic chuck design. The design space will facilitate and inspire designers to improve the design quality and shorten the design time in the conceptual design.

In DSP-based SerDes application, it is essential for AFE to implement a pre-ADC equalization to provide a better signal for ADC and DSP. To meet the various equalization requirements of different channel and transmitter configurations, this paper presents a 112 Gbps DSP-Based PAM4 SerDes receiver with a wide band equalization tuning AFE. The AFE is realized by implementing source degeneration transconductance, feedforward high-pass branch and inductive feedback peaking TIA. The AFE offers a flexible equalization gain tuning of up to 17.5 dB at Nyquist frequency without affecting the DC gain. With the proposed AFE, the receiver demonstrates eye opening after digital FIR equalization and achieves 6 × 10⁻⁹ BER with a 29.6 dB insertion loss channel.

Chemical mechanical polishing (CMP) serves as an indispensable process for achieving global planarization in semiconductor manufacturing, especially as integrated circuit (IC) technology advances to sub-7 nm nodes, where atomic-level surface flatness becomes crucial. Silica abrasives, which account for over 90% of the abrasive market in advanced CMP processes, operate not through simple mechanical grinding but through a key "chemical-mechanical synergistic" mechanism: chemically softening the wafer surface, then mechanically removing the softened layer to expose a new surface, which is further softened and removed, repeating this cycle to produce a smooth wafer. Despite their prevalence, conventional silica abrasives still face challenges, including relatively low material removal rate (MRR), a tendency to agglomerate, leading to poor dispersion and surface defects, and limitations in achieving ultimate surface uniformity. Significant progress has been made to address these issues. Development has progressed from simple spherical particles to complex structural designs (such as mesoporous, hollow, and raspberry-shaped structures) to enhance slurry transport and mechanical action. Surface chemical modifications (e.g., using amino or polymer groups) can improve dispersion stability and reduce scratching. Furthermore, composites with other materials (e.g., ceria, polymers) and precise control of particle size distribution are key to enhancing performance. These innovative approaches have yielded significant performance gains. State-of-the-art slurries have demonstrated the ability to achieve surface roughness below 0.1 nm RMS. The development of silica abrasives is increasingly focused on sustainability and smart manufacturing. A prominent direction is the design of biodegradable abrasives that disintegrate after use, thereby simplifying post-chemical mechanical polishing (CMP) cleanup and minimizing environmental impact—an approach fully aligned with green manufacturing principles. This review systematically summarizes the progress of silica abrasives for CMP over the past 60 years. This summary provides theoretical insights and forward-looking strategies to overcome the current limitations of abrasive technology. We believe this review will be helpful in advancing the field of CMP abrasives towards next-generation semiconductor manufacturing.