Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, USA.
IEEE Trans Ultrason Ferroelectr Freq Control. 2010 Jan;57(1):82-7. doi: 10.1109/TUFFC.1382.
This paper reports on the first demonstration of a 1.05-GHz microelectromechanical (MEMS) oscillator based on lateral-field-excited (LFE) piezoelectric AlN contourmode resonators. The oscillator shows a phase noise level of -81 dBc/Hz at 1-kHz offset frequency and a phase noise floor of -146 dBc/Hz, which satisfies the global system for mobile communications (GSM) requirements for ultra-high frequency (UHF) local oscillators (LO). The circuit was fabricated in the AMI semiconductor (AMIS) 0.5-microm complementary metaloxide- semiconductor (CMOS) process, with the oscillator core consuming only 3.5 mW DC power. The device overall performance has the best figure-of-merit (FoM) when compared with other gigahertz oscillators that are based on film bulk acoustic resonator (FBAR), surface acoustic wave (SAW), and CMOS on-chip inductor and capacitor (CMOS LC) technologies. A simple 2-mask process was used to fabricate the LFE AlN resonators operating between 843 MHz and 1.64 GHz with simultaneously high Q (up to 2,200) and kt 2 (up to 1.2%). This process further relaxes manufacturing tolerances and improves yield. All these advantages make these devices suitable for post-CMOS integrated on-chip direct gigahertz frequency synthesis in reconfigurable multiband wireless communications.
本文报道了基于横向场激励（LFE）压电 AlN 外形模式谐振器的首个 1.05GHz 微机电系统（MEMS）振荡器的演示。该振荡器在 1kHz 偏移频率下表现出-81dBc/Hz 的相位噪声电平，相位噪声底为-146dBc/Hz，满足全球移动通信系统（GSM）对超高频（UHF）本地振荡器（LO）的要求。该电路采用 AMI 半导体（AMIS）0.5μm 互补金属氧化物半导体（CMOS）工艺制造，振荡器核心仅消耗 3.5mW 的直流功率。与基于薄膜体声波谐振器（FBAR）、表面声波（SAW）和 CMOS 片上电感和电容（CMOS LC）技术的其他千兆赫振荡器相比，该器件的整体性能具有最佳的品质因数（FoM）。采用简单的 2 掩模工艺制造 LFE AlN 谐振器，工作频率在 843MHz 至 1.64GHz 之间，同时具有高 Q（高达 2200）和 kt2（高达 1.2%）。该工艺进一步放宽了制造公差并提高了成品率。所有这些优势使得这些器件适用于 CMOS 后集成的片上直接千兆赫频率合成，用于可重构多频带无线通信。
