34 entries, filtered by: Analog
Published: September 2005

During the evolution of RF bipolar transistors, much efforts were spent to optimize the base design. Device engineers came up with concepts like graded dopant profiles, SiGe and SiGe:C base layers, elevated base structures, etc. Regarding the collector, selectively implanted collectors (SIC) were introduced to increase both the cutoff frequency ft and the maximum frequency of oscillation fmax. In this work we focus on the collector-emitter breakdown voltage BVCE0 and its relation to ft for differently designed SICs of Si-based RF bipolar transistors.


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Published: March 2003

Standard high frequency n-p-n poly emitter transistor pairs show a significant parameter offset during the matching characterization depending on the position on the wafer. Special octagon matching transistors on the other hand have a good matching behavior. The main reason for the offset of the high frequency transistors is a dimensional difference in the emitter cut due to an non-uniform development process of the resist mask for the emitter cut etch and / or proximity effects. By the use of a modified photo resist and development process the matching characteristics for all used transistor types could be significantly improved.


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Published: April 2002

We attain a PIN photodiode combining high responsivity, fast response and low capacitance in BiCMOS technology. Only a slight process modification, having no verifiable influence on the transistor parameters is necessary. We achieve bandwidths of 625MHz and 240MHz at 670 and 780nm as well as a quantum efficiency of 96.5%.


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Published: February 2002

Result of a large-area, low-capacitance lateral p-i-n photodiode in silicon-on-insulator (SOI) are presented. This photodiode possesses an antireflection coating optimized for blue light and is therefore appropriate for scintillation detector applications. An average external quantum efficiency of 78.6% and 68.4% is achieved for λ = 430 nm and 400 nm, respectively.


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