Laterally scaled Si-Si/sub 0.7/Ge/sub 0.3/ n-MODFETs with f/sub max/>200 GHz and low operating bias

Abstract

We report on the dc and RF characterization of laterally scaled, Si-SiGe n-MODFETs. Devices with gate length, , of 80 nm had = 79 GHz and max = 212 GHz, while devices with = 70 nm had as high as 92 GHz. The MODFETs displayed enhanced at reduced drain-to-source voltage, ds , compared to Si MOSFETs with similar at high ds .

DC Performance and Low Frequency Noise in n-MOSFETs using Self-Aligned Poly-Si/SiGe Gate

“…Figure 6 shows the subthreshold characteristics of the n-MOS transistor with SiGe W=20µm L poly =1.57µm for Vds = 0.1V and Vds = 1.0V (continuous lines) with a Y scale multiplied for 1x10 6 which agrees with curve (figure 3) of the reference (13). This reference had reported minimum subthreshold slope of 100 mV/dec at V DS = 0.2V for SiGe channel with p-well doped device.…”

“…The main advantages of material system Si Ge is that allows new generations of Sibased devices which are compatible with well-established Si technology and CMOS mainstream and its capability for low cost mass production. The n-MOS transistor are particularly attractive for low-power applications (4,5), since the high mobility is expected to be more previously (6), where it was shown that MODFETs maintain f T better than Si MOSFETs as the drain voltage is reduced. However, improved MODFET performance at low current levels has been more elusive (7), because scaled MODFETs tend to suffer from poor subthreshold behavior and high output conductance.…”

Low-frequency noise in buried-channel SiGe n-MODFETs

“…The Type-II band alignment at the SiGe/Si interface results in a conduction band offset, which provides electron confinement in the channel. Further details on device fabrication are reported in [11]. Fig.…”

Si-based multi-finger N-MODFET RF power devices

“…Outstanding performance results achieved from n-MODFETs, such as f T larger than 90 GHz, f max larger than 200 GHz for gate length (L G ) of 70~80 nm [2], and 0.3 dB noise figure at 2.5 GHz [3], make this type of devices very attractive for future high frequency and low power RF applications. Up to date, both n-type and p-type MODFETs [4], logic gates [5] and circuits such as transimpedence and distributed amplifiers [6]- [7] have been realized, which demonstrated the promise of these devices for more complex circuit integration.…”