example a 1000 angstrom thick titanium layer 34 was deposited over the base region and boron was implanted at a dose of 1 u00d7 10 16 ions cm 2 at an implantation energy of 20 kev the peak concentration thus produced in the base region was ions cm 3 and the junction depth was determined to be about 400 angstroms the peak concentration occurred at approximately 200 angstroms into epitaxial layer 14 in another test 1000 angstroms of titanium were deposited as metal layer 34 and boron was implanted through this metal layer at a dose of 1 u00d7 10 16 ions cm 2 and at an implantation energy of 30 kev the peak concentration was determined to be 3 u00d7 10 17 ions cm 3 this concentration occurred at the surface of epitaxial layer 14 the junction depth occurred at about 1000 angstroms the above transistors are expected to have f t 39 s on the order of 15 20 ghz the illustrated shallow junction npn bipolar transistor may be completed by the following steps not shown a layer of phosphosilicate glass can be deposited for stabilization and all contacts including base collector emitter and resistor and schottky diode contacts are patterned and etched alternatively a thick oxide layer may be deposited after the formation of the polysilicon contact pads 60 and 62 followed by etching to produce a substantially planar top surface and then patterning and etching the contacts conventional metallization processing is then used to provide interconnects in an alternative embodiment not shown metal layer 34 can be removed after the implant of the base region 66 and before the deposit of poly layer 42 this may be advantageous if the proximity of metal layer 34 to the.