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This paper explores the next stage of GaN power devices with 2-level integration of peripheral low voltage active and passive devices. The 1st level consists of protection/control/driving circuits, which potentially improves the performance and overcomes the challenges to the power devices. The 2nd level integration has high-low side on-chip integration on a 100V technology platform. The challenge of channel modulation due to substrate bias sharing is effectively eliminated by the invented new scheme. The system efficiency of DC-DC buck converter using such scheme is enhanced with lower on-state resistance and good stability.

This paper demonstrates an advanced 1.1um pixel backside illuminated CMOS image sensor with a 3D stacked architecture. The carrier wafer in conventional BSI is replaced by ASIC wafer, which contains a part of periphery circuit and is connected to the sensor wafer through bonding technology. With proper layout design and process improvement, the impact of 3D connection (Through Via, TV) on the sensor performance can be significantly minimized. In addition, for the first time, the degradation of stacked pixel performance during the folded circuit operation under sensor array is found and improved. The final stacked sensor exhibits the comparable pixel performances to conventional BSI. Furthermore, stacked architecture provides the opportunity to enhance sensor performance by the separate process tuning for sensor wafers (without any effect on ASIC wafers), leading to a further improvement of dark performance.

Backside Illumination (BSI) sensor with excellent optical performance has become the main-stream CMOS image sensor process. This work addressed the key factors and issues for 300mm BSI technology, including wafer distortion, silicon thickness variation, backside junction formation and dielectric film structure, thermal annealing and so on. It is demonstrated that with the optimized key process, a high performance 0.9um BSI pixel with low noise can be fabricated.

A switched beam technique applied to UHF band RFID reader is proposed. The proposed switched beam circuit composed of power divider, phase shifter, and beam controlling logic circuit is implemented on a 1x2 array antenna, and resulted in a -30 to 30 degrees beam switching range in three discrete angles. This capability not only enhances the sensing range and distance but also reduces the possible EMI interference. In addition, this array antenna can help effectively cancel or attenuate mutual interference among tags through antenna arrays directivity. These advantages provided by the antenna array greatly improve the performance of a RFID system in terms of scan efficiency and read rate, which makes RFID applications even more appealing.

A vehicle management system based on UHF band RFID technology is proposed. This system is applied for vehicle entering/leaving at road gates. The system consists of tag-on-car, reader antenna, reader controller, and the monitoring and commanding software. It could effective control the vehicles passing through road gate and record the vehicles' data. The entering time, leaving time, and tag number of each vehicle are all recorded and saved for further processing. By the benefit of UHF band long distance sensing ability, within nine meter the distance between vehicle and reader antenna, the signal can be accurately detected even the vehicle's speed at nearly 30 km/hr. The monitoring and commanding software can not only identify car owners' identities but also determine the gate to open or not. The accessories: video recording and pressure sensing components are flexible to add for enhancing the system's performance. This system has been tested in many field tests and the results shown that it is suitable for vehicle management and the related applications.