一些應用於毫米波接收機前端的關鍵元件之研究

此論文的前半段,主要在研究以矽製程技術製作出的主被動元件之高頻特性及模型。主動元件之部分,我們提出一個均勻分佈型的金氧半場效電晶體(MOSFET) 之小信號模型。此模型不但可以準確地描述MOSFET 的高頻特性如電流增益 (H21)、單向功率增益(U)以及S 參數等。最重要的,它可以描述由MOSFET 的閘極分佈電阻所產生之入射反射係數的曲折現象(S11 kink phenomena)。在被動元件方面,我們實現了射頻堆疊電感器、毫微米波電感器以及馬蹄形微帶線,並且分析且製作了些等效高頻模型。在變壓器的方面,我們將偶合係數(k)極高的SMIS (single-turn multi-layer stacked) 變壓器施以電感偶合電漿蝕刻技術(ICP, inductive coupling plasma etching)將變壓器下方的矽基板選擇性去除,以達到極好的高頻性能。此外,一些廣泛用於高頻的去除測試元件量測襯墊之技術 (testkey pad de-embedding)也以實驗及模擬數據作分析並比較。在論文的後半段,我們以Jazz 0.18μm SiGe BiCMOS 製程技術實現了一些應用於毫微米波接收器前端的關鍵電路。首先,以射頻堆疊電感器製作出三個低通濾波器。我們實現了ㄧ個擁有360 MHz 之-3dB 頻率以及於10MHz 擁有-1dB 中頻損耗(MIL, midband insertion loss)之三階低通濾波器。ㄧ個擁有225 MHz 之 -3dB 頻率以及於10MHz 的-1.9dB 中頻損耗之三階低通濾波器也實現了。另外, 我們也實現了可調式低通濾波器,它擁有八個不同的-3dB 頻率,分別為170, 190, 210, 230, 235, 255, 280 以及 315 MHz。其在10MHz 之中頻損耗為-2.0 dB 至 -2.28 dB 之間。另外,ㄧ個使用差動電感器的高通濾波器也被實現,它擁有46dB 之截止帶衰減能力及小於3dB 之中頻損耗,其-3dB 頻率約為14.6 GHz。再來,不同於傳統的分布型設計原理,我們以集總被動元件實現了1800 及900 之毫微米波移相電路。並且,利用可變電容之可調容值,我們提出了可調變相位差以及振幅差之方法。1800 之毫微米波移相電路於70.7~83.8 GHz 中,我們量測到了最大相位及振幅誤差為20 以及0.5 dB,且於77 GHz 時,相位及振幅誤差分別為0.140以及0.05 dB。在900 之毫微米波移相電路方面,當量測結果之輸出端加上模擬的可變電容偏壓為0V 時,最大相位及振幅誤差為20 以及0.5 dB 的頻寬為 62.6~100.2 GHz。最後,兩顆毫微米波的低雜訊放大器也被實現了。設計A 中, 我們量測到16 GHz 的3dB 頻寬,62 GHz 時得到15.8 dB 之功率增益(S21)峰值,6.8 dB 之雜訊指數。設計B 中,我們量測到17 GHz 的3dB 頻寬,70 GHz 時得到17.2 dB 之功率增益(S21)峰值,7.4 dB 之雜訊指數。

關鍵字

均勻分佈型的金氧半場效電晶體小信號模型；射頻堆疊電感器；毫微米波電感器；馬蹄形微帶線；變壓器；電感偶合電漿蝕刻技；去除測試元件量測襯墊；濾波器；毫米波移相電路；毫米波的低雜訊放大器

並列摘要

In the first half of this thesis, some active and passive devices fabricated on silicon substrate for millimeter-wave/radio-frequency (MMW/RF) applications are characterized and modeled. For the active devices, the uniformly distributed small-signal-model for MOSFET devices is demonstrated by TSMC 0.18μm CMOS technology. This model provides good fitting results for characterizing MOSFETs up to MMW region, including the S11 kink phenomenon due to the distributed gate effect by the scaling down of the length in MOSFET devices. For the passive devices, characterization and modeling of RF stacked-inductors, MMW inductors, horseshoe-shaped microstriplines are demonstrated by Jazz 0.18μm SiGe BiCMOS technology. Several commonly-used de-embedding methods for MMW passive devices are taken into comparison and discussed. SMIS (single-turn multi-layer interlaced stacked) RF/MMW transformers were implemented by TSMC 0.18μm CMOS technology and applied to ICP (inductive coupling plasma etching) technology. Selective removal of the silicon underneath a set of SMIS RF/MMW transformers with nearly perfect magnetic-coupling factor (kIM ~ 1) and high resistive-coupling factor (kRe) is demonstrated. In the later half of this thesis, several key components (circuits) for MMW front-end applications are implemented by Jazz 0.18μm SiGe BiCMOS technology due to its high ft (cutoff frequency) and fmax (maximum oscillation frequency) for the possibility of achieving high performance MMW front-end. First of all, low-pass filters (LPFs) based on the RF-stacked inductors were implemented. A 3rd – order LPF with -3dB frequency at 360 MHz and midband insertion loss (MIL) of -1.0 dB at 10 MHz was implemented. Besides, a 5th – order LPF with -3dB frequency at 225 MHz and MIL of -1.9 dB was implemented. For the tunable design, a 5th – older LPF with tunable capacitor cells can achieve eight different cutoff frequencies (-3dB frequencies) of 170, 190, 210, 230, 235, 255, 280 and 315 MHz. The MILs of this tunable filter are ranging from -2.0 dB to -2.28 dB at 10 MHz. By the way, a high-pass filter (HPF) with stop-band-attenuation of more than 46 dB and insertion loss of below 3 dB was also implemented using differential inductors. Second, two lumped out-of-phase power splitters, 1800 and 900, were designed and implemented based on synthetic transmission lines (TLs). The measured results are excellent for 1800 splitter at 77 GHz, which have phase difference of 179.860 and amplitude difference of 0.05 dB. Within the range of 70.7 ~ 83.8 GHz, the maximum phase and amplitude errors are 20 and 0.5 dB, respectively. On the other hand, the tunable lumped-element splitter is demonstrated by attaching a simulating MOS varactor onto the measurement of 900 lumped-element splitter. It can achieve phase and amplitude difference of 90.130 and 0.038 dB at 77GHz with MOS varactor biased at 0 V. It has the maximum phase and amplitude errors of 20 and 0.5 dB within the range of 62.6 ~ 100.2 GHz. Finally, two broadband MMW LNAs were designed and implemented. Design A has a 3-dB bandwidth of 16 GHz and achieves peak |S21| of 15.8 dB at 62 GHz with measured NF of 6.8 dB at 62 GHz and is kept below 8 dB across the band. This LNA draws 9.6 mA from a 2.5 V supply, which has power consumption of 24mW. On the other hand, design B LNA has shown a 3-dB bandwidth of 17 GHz and achieves peak |S21| of 17.2 dB at 70 GHz. The measured NF is 7.4 dB at 70 GHz and is kept below 8 dB across the band we measured. This LNA draws 13.5 mA from a 3.3 V supply, that is, 44mW power consumption.

並列關鍵字

uniformly distributed small-signal-model for MOSFET ； RF stacked-inductors ； MMW inductors ； horseshoe-shaped microstriplines ； transformers ； ICP ； pad de-embedding ； filters ； MMW out-of-phase power splitters ； MMW LNAs