高性能螺线管微电感的制作

利用MEMS技术制作了高性能的空芯螺线管型射频微机械电感.这种微电感采用铜线圈以减小线圈寄生电阻,整个微电感的面积是880μm×350μm,与平面螺旋型微电感相比,有效地节省了芯片面积.测试结果表明,微电感在较宽的工作频率范围内具有高Q值,微电感最大Q值为38(@6GHz),对应的电感量为1.82nH.     

高性能螺线管微电感的制作

利用MEMS技术制作了高性能的空芯螺线管型射频微机械电感.这种微电感采用铜线圈以减小线圈寄生电阻,整个微电感的面积是880μm×350μm,与平面螺旋型微电感相比,有效地节省了芯片面积.测试结果表明,微电感在较宽的工作频率范围内具有高Q值,微电感最大Q值为38(@6GHz),对应的电感量为1.82nH.     

MEMS磁芯螺线管微电感的制作工艺研究

采用微机电系统(MEMS)技术制作了磁芯螺线管微电感,该技术包括UV-LIGA、干法刻蚀技术、抛光和电镀技术等。研制的微电感大小为1500μm×900μm×100μm,线圈匝数为41匝,宽度为20μm,线圈之间的间隙为20μm,高深宽比为5∶1。测试结果表明:在1～10MHz频率下,其电感量为0.408～0.326μH,Q值为1.6～4.2。     

用于5～6GHz无线局域网的硅螺旋电感设计

提出一种设计和优化电感版图结构的方法.采用低电阻系数硅衬底和0.18μm Cu/SiO2互连工艺技术,设计出一组工作在5.7GHz的电感,同时优化了版图结构,例如内部磁芯大小、线圈宽度、线圈间距(0.2～11nH)等.与使用原有设计方法测出的电感的Q值相比,经过优化的5.7GHz电感的Q值可改进到5～8.     

用于5～6GHz无线局域网的硅螺旋电感设计

提出一种设计和优化电感版图结构的方法.采用低电阻系数硅衬底和0.18μm Cu/SiO2互连工艺技术,设计出一组工作在5.7GHz的电感,同时优化了版图结构,例如内部磁芯大小、线圈宽度、线圈间距(0.2～11nH)等.与使用原有设计方法测出的电感的Q值相比,经过优化的5.7GHz电感的Q值可改进到5～8.     

平面磁芯螺旋结构微电感的性能研究

采用MEMS技术(包括光刻、电镀、反应离子刻蚀和机械抛光等)研制了平面磁芯螺旋结构微电感,磁芯材料为铁基纳米晶带材。其中线圈匝数为18匝,线圈导体的宽度和间隙均为30μm,厚度为20μm;电感的尺寸为3mm×3mm。测试结果表明:在频率为1~10MHz时,电感量和品质因数分别为3.2~1.2μH和2.3~1.1;在1MHz下,电感量和品质因数分别为3.2μH和2.3,可应用于微型化DC/DC变换器。     

双层悬空结构射频微电感制作研究

利用MEMS工艺制作了一种双层悬空结构的圆形射频微电感,研究了双层结构微电感中微带线宽度对其性能的影响。研究表明,双层悬空结构的圆形射频微电感不仅具有较大的电感量,而且其Q值也较高;双层微电感的Q值随微带线宽度的增大而升高,而电感量则随微带线宽度的增大而降低。对于微带线宽度为60μm的双层微电感,在频率2～4GHz时,其电感量可达到5nH左右,Q值达到20。     

应用于射频前端的高Q值SiGe HBT有源电感

针对传统的共基-共射(CB-CE)回转器有源电感的品质因子Q值低等缺点,应用Cascode结构把CB-CE有源电感改进为共基-共射-共基(CB-CE-CB)有源电感,推导出等效电路及等效阻抗表达式。最后基于Jazz 0.35μm SiGe BiCMOS工艺,利用ADS软件完成电路设计与仿真,应用Cadence Virtuoso平台完成版图设计。改进之后的有源电感,通过改变外加偏置条件,实现了电感值和品质因子Q值的可调,电感值可调范围为0.35～2.72 nH,Q值最大值可达1 172,版图面积仅为51μm×35μm。该有源电感应用于射频电路中,可取代无源电感。与无源电感相比,品质因子Q值明显提高,版图面积大大减小,更利于集成。     

MEMS技术制作的螺线管微电感

考虑和分析了螺线管微电感的几何结构参数对微电感性能的影响,利用MEMS技术制作了四种不同几何结构的高性能射频螺线管微电感。这些微电感采用铜线圈,以减小线圈寄生电阻,且制作工艺简单,成本低,与IC相兼容。测试结果表明,微电感在较宽的工作频率范围内具有较高的Q值,在频率分别为6 GHz,4.4 GHz,5.8 GHz和5.6 GHz,微电感Q峰值为38,19.1,24.1和21.9,所对应的电感量为1.81 nH,1.07 nH,1.03 nH和1.17 nH。     

双层悬空结构片状微电感研究

利用MEMS工艺制作了一种双层悬空结构的圆形片状微电感，并研究了其在S波段的性能。双层微电感的底层线圈制作在玻璃衬底平面上，外径为500μm，匝数为2，导线宽度70μm，导线间距15μm，顶层线圈的悬空高度为20μm，顶层线圈的匝数为1．5，其它结构参数与底层线圈相同。研究表明，所制作的双层结构微电感在2GHz～4GHz时其电感量达到2．2nH，其品质因数达到22。在制作过程中首次引入的光刻胶抛光工艺大大简化了微电感的制作过程。     

Surface micromachined solenoid on-Si and on-glass inductors for RFapplications

RF performance of surface micromachined solenoid on-chip inductors fabricated on a standard silicon substrate (10 Ω·cm) has been investigated and the results are compared with the same inductors on glass. The solenoid inductor on Si with a 15-μm thick insulating layer achieves peak quality (Q-) factor of 16.7 at 2.4 GHz with inductance of 2.67 nH. This peak Q-factor is about two-thirds of that of the same inductor fabricated on glass. The highest performance has been obtained from the narrowest-pitched on-glass inductor, which shows inductance of 2.3 nH, peak Q-factor of 25.1 at 8.4 GHz, and spatial inductance density of 30 nH/mm². Both on-Si and on-glass inductors have been modeled by lumped circuits, and the geometrical dependence of the inductance and Q-factor have been investigated as well     

Fabrication and performance of a novel suspended RF spiral inductor

A novel suspended radio frequency (RF) spiral inductor was fabricated on glass substrate by using the microelectromechanical systems (MEMS) technology. The suspended spiral inductor is sustained with the T-shaped pillars. Great improvements in Q-factor have been achieved because of the separation between the substrate and the inductor. In the fabrication process, fine polishing of the photoresist is used to simplify the processes and ensure the seed layer and the pillars contact perfectly, and dry etching technique is used to remove the seed layer. The inductance and Q-factor are measured using the HP 8722D network analyzer in the frequency range of 0.05-10 GHz. The maximum quality factor of this inductor is 37 for the inductance of 4.2 nH with a suspended height of 60 /spl mu/m. Also, the relationship between the maximum quality factor and the suspended height were studied; the maximum quality factor grows gradually with the increase of the suspended height.     

Flip chip assembled MEMS inductors

High performance suspended MEMS inductors produced using a flip chip assembly approach are described. An inductor structure is fabricated on a carrier and then flip chip assembled onto a substrate to form a suspended inductor for RF-IC applications with significant improvement in Q-factor and frequency of operation over the conventional IC inductors. A spiral MEMS inductor has been successfully produced on a silicon substrate with an air gap of 26 /spl mu/m between the inductor structure and the substrate. The inductance of the device was measured to be /spl sim/2 nH and a maximum Q-factor of 19 at /spl sim/2.5 GHz was obtained after pad/connector de-embedding.     

Air Cavity Incorporation to LTCC Spiral Inductor for High Q-factor and SRF

We have devised a new LTCC spiral inductor incorporating an air cavity underneath for high Q-factor and high self-resonant frequency (SRF). The air cavity employed under the spiral reduces the shunt capacitance of the inductor, and results in high Q-factor and SRF of the embedded inductors. The optimized spiral inductor with the embedded air cavity shows a maximum Q of 51 and SRF of 9.1 GHz, while conventional spiral inductor has a maximum Q of 43 and SRF of 8 GHz with effective inductance of 2.7 nH.     

Packaging-compatible high Q microinductors and microfilters forwireless applications

To meet requirements in mobile communication and microwave integrated circuits, miniaturization of the inductive components that many of these systems require is of key importance. At present, active circuitry is used which simulates inductor performance and which has high Q-factor and inductance; however, such circuitry has higher power consumption and higher potential for noise injection than passive inductive components. An alternate approach is to fabricate integrated inductors, in which lithographic techniques are used to pattern an inductor directly on a substrate or a chip. However, integrated inductors can suffer from low Q-factor and high parasitic effects due to substrate proximity. To expand the range of applicability of integrated microinductors at high frequency, their electrical characteristics, especially quality factor, should be improved. In this work, integrated spiral microinductors suspended (approximately 60 μm) above the substrate using surface micromachining techniques to reduce the undesirable effect of substrate proximity on the inductor performance are investigated. The fabricated inductors have inductances ranging from 15-40 nH and Q-factors ranging from 40-50 at frequencies of 0.9-2.5 GHz. Microfilters based on these inductors are also investigated by combining these inductors with integrated polymer filled composite capacitors     

Experimental analysis of the effect of metal thickness on the quality factor in integrated spiral inductors for RF ICs

The effect of metal thickness on the quality (Q-) factor of the integrated spiral inductor is investigated in this paper. The inductors with metal thicknesses of 5/spl sim/22.5 /spl mu/m were fabricated on the standard silicon substrate of 1/spl sim/30 /spl Omega//spl middot/cm in resistivity by using thick-metal surface micromachining technology. The fabricated inductors were measured at GHz ranges to extract their major parameters (Q-factor, inductance, and resistance). From the experimental analysis assisted by FEM simulation, we first reported that the metal thickness' effect on the Q-factor strongly depends on the innermost turn diameter of the spiral inductor, so that it is possible to improve Q-factors further by increasing the metal thickness beyond 10 /spl mu/m.     

一种适用于多波段无线通信的品质因数增强型的CMOS射频滤波器

提出了一种使用品质因数增强型的有源电感的射频带通滤波器,描述了在宽射频频段上可调谐的品质因数增强型的有源电感设计技术,而且解释了与有源电感噪声和稳定性相关的问题.该滤波器采用0.18μm CMOS工艺制造,它所占用芯片的有效面积仅为150μm×200μm.测试结果表明:该射频滤波器中心频率为2.44GHz时,3dB带宽为60MHz,中心频率可在2.07～2.44GHz范围内调谐,1dB压缩点为-15dBm,而静态功耗为10.8mW;在中心频率为2.07GHz时,滤波器的品质因数可达到103.     

A Copper/Polyimide Fabrication Process for Fabricating High-Inductance Microinductor

This paper reports on a technological process that combines copper as conductor, permalloy as magnetic core material, and polyimide as insulation material to complete a microinductor on glass with high inductance. The shape of the magnetic core scheme was rectangular, of which the width of the long side and short side were 1.4 and 0.6 mm, respectively. The dimensions of the inductor are 3.86 mm times 3.94 mm times 90 mum with coil width of 20 mum and space of 35 mum. The results show that the maximum inductance is 4 muH at 1 MHz, and the maximum quality factor (Q-factor) is 1.5 at 2 MHz.