Method for formation of platinum silicic layer
Abstract
Abstract PURPOSE:To enable to indirectly monitor the condition of formation of a silicic platinum layer by a method wherein the variation of the resistance value occurring before and after the disposition process of the platinum silicic layer having the prescribed sheet resistance value. CONSTITUTION:A B-ion is injected on the surface of an N type Si substrate, excluding an SiO2 film, an annealing is performed thereon, a heat treatment is performed in an oxidizing atmosphere, the SiO2 film on the surface is removed by etching and a monitor substrate is formed. The substrate to be used for an element is pre-treated together with the monitor substrate and a Pt is sputtered in an Ar atmosphere. After formation of the Pt film having the prescribed thickness, the Ar is shut off, evacuated and picked out after cooling. After said substrate and the monitor substrate are treated in an N2 at the temperature of 600 deg.C for about 20min, they are processed in the mixture of nitric acid, hydrochloric acid and water at the mixing ratio by volume of 1:3:4 at the temperature of 80 deg.C for about 10min and then the unnecessary Pt is removed by etching. At this stage, the SiO2 film on the monitor substrate is removed using an HF solution and the sheet resistance value of the monitor substrate is measured. If this value is appropriate, the substrate for the element, which was processed together with the monitor substrate at the same time, is considered to have nothing unusual in the silicic platinum processing. Through this constitution, an abnormal substrate can be removed.
Inventors
- 👤 Mitsuo Sakamoto
Bibliographic Details
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