Heterostructure bipolar transistors and integrated circuits

IEEE Invited Paper Abstmct-Two new epiW techadogies have emerged in recent yeus(mdeculnrbeunepitaxy(MBE)andm~c&e-miadnpor deposition (MOO)), which offer the promise of making highly advanced heterostnrctures routinely available. Wbile many kinds of dew will benefit, the principal and first beneticiuy will be bipolar trmsistors. The mklyhg central principle is the use of e m gap variations beside electdc tie & to contrd the forces acting on electrons and holes, aeprrptely md independently of each oh. The dtiDg greater design freedom pennits a re-optimization of doping levels and geometries, leading to higher speed devices. Microwave transistors with maximum oscillntion frequendes above 100 GHz and digital switching trpnsistors with switching times below 10 ps &odd become aniLbk. AninvertedtrPnsistorstructurewithasmrllercoILectorontopanda lprser emitter on the bottom becomes possible, with speed advantages over the common “emitterup ” design. Doublehetetostructure