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An analysis of the experimental results in the fabrication of complementary metal oxide semiconductor (CMOS) active pixel image sensors was presented. The CMOS technology, which was employed on the construction of the pixel sensors, was not modified to determine the impact of device scaling on the image sensing performance. The analysis revealed that the rise and fall transition times of output signal were long but the basic operations of the pixels were unaffected.

Use of a semiconductor-insulator-semiconductor (SIS) heterostructure to determine Si/Si(1-x)Ge(x) valence band discontinuity on (100) unstrained Si indicates that the bottom Si/Si(1-x)Ge(x) interface has a low valence band discontinuity when the Ge composition exceeds 10%. The application of a new data analysis method helps derive the valence band discontinuity values. An experimental evaluation of the discontinuity shows a value of 6.4x million electron volts for Ge compositions ranging between 0% and 17.5%.

A study of SiGe-channel heterojunction p-MOSFETs includes the selection of the transistor gate material, optimization of the silicon-germanium channel profile and the adjustment of threshold voltage gate-oxide thickness. The importance of optimization of the SiGe-channel profile and the advantages of SiGe-channel doped p-MOSFETs are discussed.

The ac performance issues connected with the optimization of the epitaxial silicon- and silicon-germanium-base bipolar technologies for liquid nitrogen temperature (LNT) conditions are analyzed. Results show significant developments in terms of cooling under realistic loading conditions such that dc and ac results imply the potential of bipolar technology as applied to cryogenic purposes.

Considerations for direct current design in relation to the optimal epitaxial silicon- and silicon-germanium (SiGe)-base bipolar transistors for liquid nitrogen temperature (LNT) conditions are analyzed. Results show that the thin and abrupt base profiles processed epitaxially are conducive to low-temperature operations. LNT conditions also encourage a vertical profile with lightly doped spacer layers and a graded-bandgap SiGe base.