Methods for producing bipolar transistors are provided. In one embodiment, the method includes producing a bipolar transistor including first and second connected emitter-base (EB) junctions of varying different depths. A buried layer (BL) collector is further produced to have a third depth greater than the depths of the EB junctions. The emitters and bases corresponding to the different EB junctions are provided during a chain implant. An isolation region may overlie the second EB junction location. The BL collector is laterally spaced from the first EB junction by a variable amount to facilitate adjustment of the transistor properties. The BL collector may or may not underlie at least a portion of the second EB junction. Regions of opposite conductivity type overlie and underlie the BL collector to preserve breakdown voltage. The transistor can be readily “tuned” by mask adjustments alone to meet various device requirements.