A　method　of　non-uniform　finger　spacing　is　proposed　to　enhance　thermal　stability　of　a　multiple　finger　power　SiGe　heterojunction　bipolar　transistor　under　different　power　dissipations.　Temperature　distribution　on　the　emitter　fingers　of　a　multi-finger　SiGe　heterojunction　bipolar　transistor　is　studied　using　a　numerical　electro-thermal　model.　The　results　show　that　the　SiGe　heterojunction　bipolar　transistor　with　non-uniform　finger　spacing　has　a　small　temperature　difference　between　fingers　compared　with　a　traditional　uniform　finger　spacing　heterojunction　bipolar　transistor　at　the　same　power　dissipation.　What　is　most　important　is　that　the　ability　to　improve　temperature　non-uniformity　is　not　weakened　as　power　dissipation　increases.　So　the　method　of　non-uniform　finger　spacing　is　very　effective　in　enhancing　the　thermal　stability　and　the　power　handing　capability　of　power　device.　Experimental　results　verify　our　conclusions.