Si-based integrated circuits have been intensively developed over the past several decades through ultimate device scaling. However, the Si technology has reached the physical limitations of the scaling. These limitations have fuelled the search for alternative active materials (for transistors) and the introduction of optical interconnects (called “Si photonics”). A series of attempts to circumvent the Si technology limits are based on the use of III-V compound semiconductor due to their superior benefits, such as high electron mobility and direct bandgap. To use their physical properties on a Si platform, the formation of high-quality III-V films on the Si (III-V/Si) is the basic technology ; however, implementing this technology using a high-throughput process is not easy. Here, we report new concepts for an ultra-high-throughput heterogeneous integration of high-quality III-V films on the Si using the wafer bonding and epitaxial lift off (ELO) technique. We describe the ultra-fast ELO and also the re-use of the III-V donor wafer after III-V/Si formation. These approaches provide an ultra-high-throughput fabrication of III-V/Si substrates with a high-quality film, which leads to a dramatic cost reduction. As proof-of-concept devices, this paper demonstrates GaAs-based high electron mobility transistors (HEMTs), solar cells, and hetero-junction phototransistors on Si substrates.

SiO is a commonly used insulation layer for QCLs but has high absorption peak around 8 to 10 µm. Instead of SiO, we used YO as an insulation layer for DC-QCL and successfully demonstrated lasing operation at the wavelength around 8.1 µm. We also showed 2D numerical analysis on the absorption coefficient of our DC-QCL structure with various parameters such as insulating materials, waveguide width, and mesa angle.

A transient voltage suppression (TVS) diode with abrupt junctions has been developed using the low-temperature epitaxy and process technology. The triggering voltage at 6 V could be precisely controlled by the thickness and dopant concentration. The reliability of TVS device is confirmed based on its electrostatic discharge (ESD) strength in conjunction with the transmission line pulse (TLP) test. As a result, the device could exceed 28 A TLP, ± ± ± ±8 kV MM, and could withstand IEC 61000-4-2 up to ± ± ± ±19kV. Moreover, TVS diode exhibited very low leakage current, small capacitance, fast respond time and high cut off frequency of 2nA, 60 pF, 8 ps, and 52 MHz, respectively. TVS diode can be also used for a digital communication line as well as an ESD/EMI filter attenuating the RF noise in MHz range.

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We fabricated interdigitated germanium (Ge) metal-semiconductor-metal photodetectors (MSM PDs) with interdigitated platinum (Pt) finger electrodes and investigated the effects of Pt finger width and spacing on their spectral response. An increase in the incident optical power enhances the creation of electron-hole pairs, resulting in a significant increase in photo current. Lowering of the Schottky barrier could be a main cause of the increase in both photo and dark current with increasing applied bias. The manufactured Ge MSM PDs exhibited a considerable spectral response for wavelengths in the range of 1.53-1.56 μm, corresponding to the entire C-band spectrum range. A reduction in the area fraction of the Pt finger electrode in the active region by decreasing and increasing finger width and spacing, respectively, led to an increase in illuminated active area and suppression of dark current, which was responsible for the improvement in responsivity and quantum efficiency of Ge MSM PDs.