SEMICONDUCTOR DEVICE, AND FORMING OF LAYER UNIFORM IN FLATNESS AND THICKNESS

摘要

PROBLEM TO BE SOLVED: To provide a method for forming a layer which is uniform in flatness and thickness on a semiconductor chip or on a semiconductor device provided with a trench. SOLUTION: An oxide thermal pad layer 104 is formed on a semiconductor substrate 102 through a thermal oxidation method, a nitride insulating layer 106, a buffer layer 108 of oxide or preferably TEOS(tetraethyl oxosilane), and a SiN mask layer 110 are formed thereon through a CVD(chemical vapor deposition) method, and a hard mask layer 112 containing BSG(borosilicate glass) or TEOS is formed on the mask layer 110. Then, a semiconductor device is manufactured, a trench is provided to the device, filler is filled, a polishing is carried out up to a pad stop, and an etching operation is carried out using the buffer layer as an etching stopper for removing the pad stop and the buffer layer, whereby a surface layer which is nearly flat and uniform in thickness can be obtained.