The effect of the conditions of the collector formation on electrical characteristics of the packaged SiGe hetero-junction bipolar transistors (HBT) were investigated. While the DC characteristics of SiGe HBTs such as IV characteristics, forward current gain, Early voltage, and breakdown voltage were hardly changed after packaging, the AC characteristics such as fr and fmax were degraded severely. With the rise of the collector concentration, the breakdown voltage decreased but the fr increasedd. Additionally, β and fr values were kept high in the range of elevated collector current due to the increase of th e critical current density for the onset of the Kirk effect. The devices As implanted before the collector deposition showed lower breakdown voltage and higher fr than the others, which seems to be originated from the As up-diffusion resulting in the thinner collector.