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Silicon epitaxial growth with SiH2C12 (DCS) is modeled within a realistic therma]-fluid environment using a detailed reaction mechanism. The proposed reaction mechanism includes both gas-phase and surface reactions. It accounts for surface-adsorbed species and individual surface coverages to predict deposition rates. The predicted deposition rates are compared to measured growth rates at different temperatures, pressures, and DCS flow rates. The agreement between predicted and measured growth rates is found to be very good. The suggested reaction mechanism is based on two reaction pathways. First, DCS adsorbs directly on the Si surface and decomposes there while desorbing H2, HCI, and SiCl2. Second, at temperatures above 800~ the thermal activation gets high enough to allow the pyrolysis of DCS to SiCI2 and H2 in the gas phase. The generated SiCl2 reacts on the silicon surface, representing the second deposition pathway. The two reaction pathways are valid for all temperatures. The dominance of one or the other pathway at a given temperature results self-consistently from the different thermal activation of the individual chemical reactions involved.

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spectrum analyzer and Agilent 83752B signal source were used to characterize the phase noise and locking range performance of the ILFD. The measured tuning range of the free-running ILFD, from 2.29 GHz to 2.94 GHz, is shown in Figure 3. At V dd ϭ 1.1 V and tail bias V bias ϭ 1 V, the current and power consumption of the core are 2.38 mA and 2.6 mW, respectively. Figure 4 shows the measured relationship between input sensitivity and operating frequency of the divide-by-2 frequency divider under the condition of V dd ϭ 1.1 V, V bias ϭ 1 V, and injection MOS bias V mos ϭ 2.2 V, with total operation range from 4.2 to 6.7 GHz at the injection power of 0 dBm. The locking range increases as the strength of injection signal increases. The operation range is from 4.3 to 6.3 GHz measured using only the tail injection and the operation range is from 4.3 to 6.2 GHz measured using only the direct MOS injection. Figure 4 shows the data measured using the dual-injection method where a single-ended injection signal is applied to both the base of tail and the gate of injection MOSFET. The operation range of the dual-injection ILFD topology is the largest.Figure 5(a) shows the measured phase noises of the injectionreference and injection-locked Ϭ2 ILFD. At 1 MHz offset from the 2.65 GHz, when the external injection signal is injected, the phase noise of the locked ILFD is about Ϫ127.34 dBc/Hz, while the phase noise of the injection-reference is Ϫ125.03 dBc/Hz. The improvement of locked phase noise relative to the injection signal at low frequency offset is about 6 dB. Figure 5(b) shows the measured output spectra of the divider before and after the locked conditions in the Ϭ2 mode. Figure 6 shows the measured relationship between input sensitivity and operating frequency of the divide-by-4 frequency divider under the condition of V dd ϭ 1.1 V, V bias ϭ 1 V, and V mos ϭ 2.2 V, with total operation locking range from 9.06 to 11.96 GHz at the injection power of 0 dBm. In the measurement a differential signal is applied to the base of tail and the gate of injection MOSFET, it is obtained from an external balun. Figure 7(a) shows the measured phase noises of the injection-reference and injection-locked Ϭ4 ILFD. At 1 MHz offset from the 2.65 GHz, when the external injection signal is injected, the phase noise of the locked ILFD is about Ϫ127.0 dBc/Hz, while the phase noise of the injection-reference is Ϫ125.7 dBc/Hz. The improvement of locked phase noise relative to the injection signal at low frequency offset is about 12 dB. Figure 7(b) shows the measured output spectra of the divider before and after the locked conditions in the Ϭ4 mode. Table 1 shows the comparison between our presented injection-locked divider and other SiGe ILFDs. CONCLUSIONA low power and wide operation range BiCMOS LC-tank ILFD circuit has been proposed and successfully implemented in the 0.35 m SiGe BiCMOS technology. The low-power function is obtained by using the dc blocking capacitors and biasing resistors so that the VCO can have a large swing and can opera...

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