Monolithic silicon-based photonic receiver

A method for building an integrated circuit using a conventional BiCMOS process the conventional BiCMOS process comprising extensive use of planarization techniques, the method comprising the steps of:

• Manufacturing, using the conventional BiCMOS process, a first phototransistor having a first base including an SiGe base layer of a pre-determined germanium composition and a thickness of more than 65 nm and less than about 90 nm;
• said first phototransistor being comprised of a number of active regions, each active region, except a bottom active region, vertically disposed over another active region;
• Manufacturing, using the conventional BiCMOS process, a second phototransistor having a second base including an SiGe base layer of a pre-determined germanium composition and a thickness of more than 65 nm and less than about 90 nm;
• said second phototransistor being comprised of a number of active regions, each active region vertically disposed over another active region;
• configuring a capacitor between a second output of the second phototransistor and a ground;
• receiving a first output from the first phototransistor and the second output of the second phototransistor into a differential amplifier;
• configuring the first phototransistor, the second phototransistor, and the differential amplifier on a silicon substrate.

A method for improving bandwidth of a photonic receiver, the method comprising the steps of:

• manufacturing, on a silicon substrate, a phototransistor having a base including an SiGe base layer of a pre-determined germanium composition and a thickness of more than 65 nm and less than about 90 nm;
• said phototransistor being comprised of a number of active regions, each active region, except a bottom active region, vertically disposed over another active region;
• manufacturing, on said silicon substrate, a transimpedance amplifier (TIA) configured to achieve a predetermined bandwidth;
• and
• configuring a capacitor to reduce an effect of collector-substrate junction on bandwidth;
• the capacitor being configured between an output of the phototransistor and an input of the TIA, the capacitor connecting the output of the phototransistor to the input of the TIA;
• obtaining, by said manufacturing steps and said configuring, a photonic receiver with improved bandwidth.

A method for improving a bandwidth of a photonic receiver, the method comprising the steps of:

• manufacturing, on a silicon substrate, a first phototransistor having a first base including an SiGe base layer of a pre-determined germanium composition and a thickness of more than 65 nm and less than about 90 nm;
• said first phototransistor being comprised of a number of active regions, each active region, except a bottom active region, vertically disposed over another active region;
• manufacturing, on the silicon substrate, a second phototransistor having a second base including an SiGe base layer of a pre-determined germanium composition and a thickness of more than 65 nm and less than about 90 nm;
• said second phototransistor being comprised of a number of active regions, each active region, except a bottom active region, vertically disposed over another active region;
• manufacturing, on the silicon substrate, a differential amplifier;
• connecting a first output of the first phototransistor to a first input of the differential amplifier;
• filtering a second output of the second phototransistor with a substantially low pass filter, thereby obtaining a filtered output and
• connecting the filtered output of the second phototransistor to a second input of the differential amplifier;
• obtaining, by said manufacturing steps, said configuring steps and said connecting, a photonic receiver with improved bandwidth is obtained.