Glass has emerged as a highly versatile substrate for various sensor and MEMS packaging applications, including electromechanical, thermal, optical, biomedical, and RF devices, due to its exceptional properties such as high geometrical tolerances, outstanding heat and chemical resistance, excellent high-frequency electrical properties, and the ability to be hermetically sealed. In these applications, Through Glass Via (TGV) technology plays a vital role in manufacturing and packaging by creating electrical interconnections through glass substrates. This paper provides a comprehensive summary of the research progress in TGV fabrication along with its integrations, including through via formation and metallization. This paper also reviews the significant qualification and reliability achievements obtained by the scientific community for TGV technology. Additionally, this paper summarizes the application of TGV technology in various sensors such as MEMS sensors and discusses the potential applications and future development directions of TGV technology.

This letter proposes a high bandwidth compact linear polarization antenna for the automotive radar millimeter-wave band of 77 GHz using five stacked glass layers scheme with high precision metal layers and through glass vias (TGVs). The radiation part of antenna is composed of four microstrip patches, wherein a single patch is only $0.55\times0.55$ mm ² , and the overall size of the package is 10 $\times 9\times $ 1 mm ³ . 6-inch glass wafers with the thickness of $230~\mu $ m or $100~\mu $ m are employed to achieve high-density interconnects and precise manufacture. The interconnects formed by the TGVs and redistribution layer (RDL) realize direct transmission and signal coupling between layers to improve transmission efficiency. The gain is more than 7 dB at frequency of 77 GHz. This proposed glass Antenna shows the superior advantages of process accuracy to realize miniaturization and System in Package (SiP) compared with that of Low-Temperature Co-fired Ceramics (LTCC) and Printed Circuit Board (PCB).

In this letter, a third-order low Insertion loss bandpass filter (BPF) is proposed by using a stacked double-layer structure through the technologies of the glass-based integrated passive device (IPD) and the through glass vias (TGVs). First, a stacked multi-layer structure was introduced to create a 3D-inductor of large inductance with a high Q factor. Then, an air cavity Metal-Insulator-Metal (MIM) structure was used to upgrade the Q factor of the capacitor. Therefore, a third-order low-loss small-sized bandpass filter can be generated by utilizing these LC elements of high Q factors. Experimental results show that the proposed BPF’s size and insertion loss is $0.018\lambda _{{0}} \times 0.013\lambda _{{0}}$ and 0.81 dB, respectively. In comparison with the existing design, the proposed BPF shows the superior advantages of smaller size and lower insertion loss.

Three-dimensional (3D) interconnection technology based on glass through vias (TGVs) has been used to integrate passive devices, and optoelectronic devices due to its superior electrical qualities, outstanding mechanical stability, and lower cost. Nevertheless, the performance and reliability of the device will be impacted by the thermal stress brought on by the mismatch of the coefficient of thermal expansion among multi-material structures and the complicated structure of TGV. This paper focuses on thermal stress evolution in different geometric and material parameters and the development of a controlled method for filling polymers in TGV interconnected structures. In addition, a numerical study based on the finite element (FE) model has been conducted to analyze the stress distribution of the different thicknesses of TGV-Cu. Additionally, a TGV interconnected structure model with a polymer buffer layer is given to solve the crack problem appearing at the edge of RDL. Meanwhile, after practical verification, in comparison to the experimental results, the FE model was shown to be highly effective and accurate for predicting the evolution of stress, and several recommendations were made to alleviate stress-related reliability concerns. An improved manufacturing process flow for the TGV interconnected structure was proposed and verified as feasible to address the RDL crack issue based on the aforementioned research. It provides helpful information for the creation of highly reliable TGV connection structures.

Thermal management poses a critical challenge in the design of modern electronic packages. This letter presents a diamond-on-chip-on-glass interposer (DoCoG) technology that incorporates polycrystalline diamond heat-spreader substrates known for their exceptional thermal conductivity. These diamonds are directly bonded to the back-side of silicon chips on a glass interposer, resulting in markedly enhanced cooling performance. The junction-to-ambient thermal resistance dropped by 28.5% due to the integration of diamond. The creation of such multi-stacked DoCoG integration and efficient cooling necessitates a diamond/chip connection that combines a minimal bonding thermal budget, high working temperature, and low thermal boundary resistance. To address this challenge, the study proposes a low-temperature bonding technique through nanolayer Cu/Au recrystallization. The effects of bonding voids on overall cooling performance were investigated. These results represent significant progress toward universal approaches for the viable integration of high-performance coolers into electronic packages, potentially enabling applications that are currently constrained by thermal limitations in heterogeneous integrations.