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Like to other two contributors said, follow the design rules. Typical electrode configuration is C-E-B because you can put the base electrode over the outside isolation thus minimizing your collector-substrate capacitance. In addition, keeping the base electrode away from your collector will also eliminate fringing capacitance to the two electrodes which would cause your Miller capacitance to increase. Have an isolation (p-junction, field ox., trench iso, etc.) around your transistor so your collector is decoupled from the rest of the die. If using an oxide/trench isolation around your transistor, you will also need a channel-stop implant (p+) to prevent tub-tub leakage. If available, include a buried layer and deep collector implant to reduce your collector series resistance. Keep base electrode as close to the emitter/base active area to minimize series base resistance. Keep you emitter/base active area as small as possible because this will determine your collector-base junction capacitance area. If you have a SIC implant, add it to improve your Ft and collector current density because it will prevent "base push-out". These are some of the basics.
1,Typical electrode configuration is C-E-B because you can put the base electrode over the outside isolation thus minimizing your collector-substrate capacitance. 2,If you have a SIC implant, add it to improve your Ft and collector current density because it will prevent "base push-out". These are some of the basics.
SIC stands for Selective Implanted Collector. It increases the collector profile under the base to about 1e17 /cm3. Because of the higher collector concentration, the onset of high-injection effect (eg. Kirk effect) is pushed out to a higher collector current. Due to this effect, Ft will continue to increase with increasing collector current.
What is Ft?
And also the first question
"1,Typical electrode configuration is C-E-B because you can put the base electrode over the outside isolation thus minimizing your collector-substrate capacitance. " Any more detail on this one?
I hope this helps. The blue-dot ring around the transistor is deep trench isolation. Notice that the base electrode sits above the deep trench layer. If you look at the cross-section, the base electrode sits above and slightly beyond the deep trench isolation. The collector-substrate capacitance (bottom) is defined from inside the deep trench edge to the other inside deep trench edge. There will be some capacitance, which doesn't vary with voltage, due to the trench isolation.
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