A bipolar transistor comprising: a substrate ; a collector comprising a plurality of alternating doped regions (303a-e, 353a-e), wherein the plurality of alternating doped regions form columns that alternate in a lateral direction from a net first conductivity to a net second conductivity which is opposite to the net first conductivity; a collector contact in electrical contact with the collector; a doped buried layer below the collector; a base in electrical contact with a base contact , wherein the base is doped to a net second conductivity type and wherein the base spans a portion of the plurality of alternating doped regions (303a-e, 353a-e); and an emitter disposed within the base , the emitter doped to a net first conductivity type, wherein a first portion of the alternating doped region under the emitter is doped to the net first conductivity type, wherein the first portion of the alternating doped region disposed under the emitter is a collector column, wherein the collector column under the emitter is self-aligned to the emitter , wherein an integral across the width of the first portion of the alternating doped region under the emitter has a value of less than about 3E12 ions/cm 2 , such that the collector column totally depletes at a reverse bias collector base voltage of magnitude less than an absolute value of BVceo; and a second portion of the alternating doped region adjacent to the first portion of the alternating doped region , wherein the second portion of the alternating doped region is doped to the net second conductivity type to a sufficient concentration such that the second portion does not totally deplete at the reverse bias. a substrate ; a collector comprising a plurality of alternating doped regions (303a-e, 353a-e), wherein the plurality of alternating doped regions form columns that alternate in a lateral direction from a net first conductivity to a net second conductivity which is opposite to the net first conductivity; a collector contact in electrical contact with the collector; a doped buried layer below the collector; a base in electrical contact with a base contact , wherein the base is doped to a net second conductivity type and wherein the base spans a portion of the plurality of alternating doped regions (303a-e, 353a-e); and an emitter disposed within the base , the emitter doped to a net first conductivity type, wherein a first portion of the alternating doped region under the emitter is doped to the net first conductivity type, wherein the first portion of the alternating doped region disposed under the emitter is a collector column, wherein the collector column under the emitter is self-aligned to the emitter , wherein an integral across the width of the first portion of the alternating doped region under the emitter has a value of less than about 3E12 ions/cm 2 , such that the collector column totally depletes at a reverse bias collector base voltage of magnitude less than an absolute value of BVceo; and a second portion of the alternating doped region adjacent to the first portion of the alternating doped region , wherein the second portion of the alternating doped region is doped to the net second conductivity type to a sufficient concentration such that the second portion does not totally deplete at the reverse bias. <EOS>