Patent ID: 6218223
Filing Date: 2001-04-17
Classification: H01L

Abstract:
A process for fabricating a semiconductor device, the device comprising a substrate having a bipolar transistor and an insulating film, the transistor having a base region of a first conductivity type presenting a first rectangular upper surface and an emitter region of a second, opposite conductivity type presenting a second rectangular upper surface, where the insulating film overlies the base region and the emitter region and has a first contact hole therethrough to the first surface and a second contact hole therethrough to the second surface, the transistor further having a base electrode provided filling the first contact hole in contact with the base region and an emitter electrode provided filling the second contact hole in contact with the emitter region, and the device further comprising a wiring connected to the emitter electrode, said process comprising the steps of:forming the first contact hole to have a first rectangular opening on the first surface such that, when a height of the first contact hole in a first direction perpendicular to the first surface is H1, a length of the first rectangular opening in a longitudinal direction perpendicular to the first direction is L1, and a width of the first rectangular opening in a second direction perpendicular to the first and longitudinal directions is W1, then L1>H1>W1;forming the second contact hole to have a second rectangular opening on the second surface such that, when a height of the second contact hole in the first direction perpendicular to the second surface is H2, a length of the second rectangular opening in the longitudinal direction perpendicular to the first direction is L2, and a width of the second rectangular opening in the second direction perpendicular to the first and longitudinal directions is W2, then L2>H2>W2;forming the base electrode in the first contact hole and the emitter electrode in the second contact hole by forming conductive material composed of Al or composed mainly of Al in the first and second contact holes by a CVD method utilizing at least a gas of an alkylaluminum hydride, so that the base electrode has dimensions of H1, L1 and W1 and the emitter electrode has dimensions of H2, L2 and W2 and whereby lengths L1, L2 of the base electrode and the emitter electrode are in parallel in the longitudinal direction; andforming the wiring on the insulating film.