Formation of layer of semiconductor device through ion implantation

Abstract

Abstract PURPOSE:To form an ion implanting layer in arbitrary concentration distribution in the depth direction of a substrate by varying the energy of implanting ion beams continuously or by stages. CONSTITUTION:An N epitaxial layer 2 is formed onto a P-type substrate 1, and a mask 4 for implanting ions is executed. O<+> ions are implanted so as to reach to the substrate 1 from the surface, thus shaping a pair of SiO2 layers 3. Beam energy is changed continuously or by stages at that time. The range of variation of beams is brought to approximately several keV-200keV, and beam currents are kept constant with the fluctuation of energy or beam currents are controlled, thus acquiring desired concentration distribution. According to the constitution, a region in which the concentration distribution of O<+> ions is kept constant is formed deeply up to the substrate 1, thus obtaining the SiO2 layers 3 for element isolation.

Inventors

• 👤 Hideki Suzuki

Bibliographic Details