MANUFACTURE OF SEMICONDUCTOR DEVICE

PURPOSE:To simplify the process of manufacture of the semiconductor device of interlayer isolation construction by a method wherein an electrode window, to be used to lead out an earth electrode from the polycrystalline Si layer which is buried in a V- shaped interelement isolation groove, is formed simultaneously with the electrode window of an element region. CONSTITUTION:An N type buried layer 2 and a P type channel cut region 3 surrounding the layer 2 are formed on the P type Si substrate 1 having the surface 100 , and an N type collector layer 4 is epitaxially grown on the whole surface. Then an SiO2 film 8a and an Si3N4 layer 22 are coated by lamination, using a thermal oxidization for the former and a CVD method for the latter. A plurality of strip form windows 23 are provided on the films 8a and 22 in such a manner that they are orthogonally intersecting along the direction , and a V-shaped element isolation groove 7, having a side-etching region 17, is provided by performing an etching. Subsequently, an SiO2 film 8b is coated on the side wall of the groove 7, a P-doped polycrystalline Si layer 9 is filled in the groove, an SiO2 film 8c is covered on the above, a P type base region 10 is formed by performing an ion implantation, and an N type emitter region 11 is provided on the above. Then, an SiO2 film 8d is coated on the whole surface, and windows 18-21 to be used for an earth, an emitter, a base and a collector are formed simultaneously.