Micromachined high-performance RF passives in CMOS substrate

Abstract

This review systematically addresses the micromachining technologies used for the fabrication of high-performance radio-frequency (RF) passives that can be integrated into low-cost complementary metal-oxide semiconductor (CMOS)-grade (i.e. low-resistivity) silicon wafers. With the development of various kinds of post-CMOS-compatible microelectromechanical systems (MEMS) processes, 3D structural inductors/transformers, variable capacitors, tunable resonators and band-pass/low-pass filters can be compatibly integrated into active integrated circuits to form monolithic RF system-on-chips. By using MEMS processes, including substrate modifying/suspending and LIGA-like metal electroplating, both the highly lossy substrate effect and the resistive loss can be largely eliminated and depressed, thereby meeting the high-performance requirements of telecommunication applications.

Investigation of the effects of silica coating on the thermal conductivity and porosity of aluminum nitride after sintering

“…Figure 6 Table 2 shows the densities of these samples measured by the Archimedean method and the calculated ideal densities and porosities. The measured density of the AN sample is 2.06 g/cm 3 and the porosity of this sample was approximately 23.4%. As for the ANc sample, the measured density was 2.31 g/cm 3 and the porosity was 13.5%.…”

“…The measured density of the AN sample is 2.06 g/cm 3 and the porosity of this sample was approximately 23.4%. As for the ANc sample, the measured density was 2.31 g/cm 3 and the porosity was 13.5%. These results were consistent with the SEM images, revealing that the silica coating on the aluminum nitride powder enables it to increase the density of sintered samples containing the powder and silica powder.…”

“…The development of semiconductor chips for high voltage control and high-speed wireless communications is progressing, miniaturization of the package substrates contained in semiconductor chips is also required by industry [1][2][3][4]. These packages are usually manufactured using a low-temperature co-fired ceramic (LTCC) technology [5,6], the sintering temperature of which is approximately 1000°C due to the use of glass for the substrates.…”

MEMS inductor fabrication and emerging applications in power electronics and neurotechnologies

“…RF MEMS and power electronics applications of MEMS inductors account for over 300 studies. Excellent reviews on RF applications exist 1,2 . However, there are no reviews on the three other applications.…”

A design technique for concurrent multiband tunable loads from 0.4–6GHz with independent Q tuning

“…The performance of these components is constantly improving at radio frequency (RF) frequencies [12] and are already finding use in antenna tuning circuits [13]. The combination of these technologies with complementary metal oxide semiconductor (CMOS) processes is currently an active area of research [14].…”