Substrate options and add-on process modules for monolithic RF silicon technology

Burghartz, Joachim N.; Bartek, M.; Rejaei, B.; Sarro, P.M.; Polyakov, A.; Pham, Nga; Boullaard, E.; Ng, K.T.

doi:10.1109/bipol.2002.1042878

Cited by 21 publications

(11 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Any of those steps should preferably be arranged as a modular addition to the core device integration process [30]. Standard silicon wafer material, grown by using the Czochralski technique, is still limited to resistivities below 100 cm [31], but the recently introduced magnetic Czochralski wafers may allow for resistivities up to 1 k cm [32].…”

Section: Optimization Guidelinesmentioning

confidence: 99%

On the design of RF spiral inductors on silicon

Burghartz

Rejaei

2003

IEEE Trans. Electron Devices

Self Cite

254

View full text Add to dashboard Cite

Abstract-This review of design principles for implementation of a spiral inductor in a silicon integrated circuit fabrication process summarizes prior art in this field. In addition, a fast and physics-based inductor model is exploited to put the results contributed by many different groups in various technologies and achieved over the past eight years into perspective. Inductors are compared not only by their maximum quality factors ( max ), but also by taking the frequency at max , the inductance value ( ), the self-resonance frequency ( SR ), and the coil area into account.It is further explained that the spiral coil structure on a lossy silicon substrate can operate in three different modes, depending at first order on the silicon doping concentration. Ranging from high to low substrate resistivity, inductor-mode, resonator-mode, and eddy-current regimes are defined by characteristic changes of max , , and SR . The advantages and disadvantages of patterned or blanket resistive ground shields between the inductor coil and substrate and the effect of a substrate contact on the inductor are also addressed in this paper. Exploring optimum inductor designs under various constraints leverages the speed of the model. Finally, in view of the continuously increasing operating frequencies in advancing to new generations of RF systems, the range of feasible inductance values for given quality factors are predicted on the basis of optimum technological features.

show abstract

Section: Optimization Guidelinesmentioning

confidence: 99%

On the design of RF spiral inductors on silicon

Burghartz

Rejaei

2003

IEEE Trans. Electron Devices

Self Cite

254

View full text Add to dashboard Cite

show abstract

“…This, however, brings several technological issues in focus that may form bottlenecks, in particular the considerable losses in the conventional silicon substrates [6]. Currently, resistivities of at most [10][11][12][13][14][15][16][17][18][19][20] cm [low-resistivitysilicon(LRS)]arebeingused.Thiscorrespondsto conductivities that lead to considerable substrate losses and, thus, to excessive attenuation of integrated transmission lines [7] and reduced quality factors of on-chip inductors [8].…”

mentioning

confidence: 99%

Surface-passivated high-resistivity silicon as a true microwave substrate

Spirito

Paola

Nanver

et al. 2005

IEEE Trans. Microwave Theory Techn.

Self Cite

View full text Add to dashboard Cite

Abstract-This paper addresses the properties of a surface-passivated (enhanced) high-resistivity silicon (HRS) substrate for use in monolithic microwave technology. The detrimental effects of conductive surface channels and their variations across the wafer related to the local oxide and silicon/silicon-dioxide interface quality are eliminated through the formation of a thin amorphous layer at the wafer surface. Without passivation, it is found that the surface channels greatly degrade the quality of passive components in HRS by masking the excellent properties of the bulk HRS substrate and by causing a spread in parameters and peak values across the wafer. Moreover, it is seen that the surface passivation leads to excellent agreement of the characteristics of fabricated components and circuits with those predicted by electromagnetic (EM) simulation based on the bulk HRS properties. This is experimentally verified for lumped (inductors and transformers) and distributed (coplanar waveguide, Marchand balun) passive microwave components, as well as for a traveling-wave amplifier, through which also the integration of transistors on HRS and the overall parameter control at circuit level are demonstrated. The results in this paper indicate the economically important possibility to transfer microwave circuit designs based on EM simulations directly to the HRS fabrication process, thus avoiding costly redesigns.Index Terms-High-resistivity silicon (HRS), inductors, Marchand balun, substrate passivation, transformers, traveling-wave amplifier (TWA).

show abstract

“…Furthermore, the surface-channel losses can be bias-dependent, leading to difficulties in parameter control [7]. The impact of a parasitic surface channel is consequently more pronounced in coplanar wave guide (CPW) structures, in which the electric field is more concentrated at the wafer surface, [6]- [9], [11] than in microstrip structures [7], [10], or spiral inductors [12]. In view of the recent attention to the application of HRS substrates in RFIC processes [13], elimination of surface channels on HRS is highly desirable.…”

Section: Introductionmentioning

confidence: 99%

“…H IGH-RESISTIVITY SILICON (HRS) has long been viewed as an ideal substrate for radio frequency integrated circuits (RFICs) [1]- [5], but surface effects tend to overshadow the potentially low RF loss levels in HRS [6]- [9]. Charges within the insulating SiO layer and at the SiO interface lead to accumulation or inversion layers at the silicon surface, contributing to an increased attenuation of integrated transmission lines [6]- [11], a reduced quality factor (Q) of on-chip spiral inductors [12], and a leakage path between integrated devices [6].…”

Section: Introductionmentioning

confidence: 99%

Surface-Passivated High-Resistivity Silicon Substrates for RFICs

Rong

Burghartz

Nanver

et al. 2004

IEEE Electron Device Lett.

Self Cite

109

View full text Add to dashboard Cite

Abstract-Surface passivation of high-resistivity silicon (HRS) by amorphous silicon thin-film deposition is demonstrated as a novel technique for establishing HRS as a microwave substrate. Metal-oxide-silicon (MOS) capacitor measurements are used to characterize the silicon surface properties. An increase of the quality factor (Q) of a 10-nH spiral inductor by 40% to = 15 and a 6.5-dB lower attenuation of a coplanar wave guide (CPW) at 17 GHz indicate the beneficial effect of the surface passivation for radio frequency (RF) and microwave applications. Regarding CPW attenuation, a nonpassivated 3000-cm substrate is equivalent to a 70-cm passivated substrate. Surface-passivated HRS, having minimum losses, a high permittivity, and a high thermal conductivity, qualifies as a close-to-ideal radio frequency and microwave substrate.

show abstract

Substrate options and add-on process modules for monolithic RF silicon technology

Cited by 21 publications

References 18 publications

On the design of RF spiral inductors on silicon

On the design of RF spiral inductors on silicon

Surface-passivated high-resistivity silicon as a true microwave substrate

Surface-Passivated High-Resistivity Silicon Substrates for RFICs

Contact Info

Product

Resources

About