| 摘要 |
PURPOSE:To accurately work a film of high melting point metal in size near the size of a mask by forming a 2-layer film of an aluminum film and a resist film on the aluminum film in a predetermined pattern on a heat resistant metal layer, and removing the metal layer by dry etching with the 2-layer film as a mask. CONSTITUTION:After tungsten is deposited 0.5mum as a heat resistant metal 9 on the entire surface of a semi-insulating GaAs substrate 6 by a sputtering method, an aluminum film 7 is formed on the tungsten 9 0.05mum thick by a vacuum depositing method, it is coated with a resist film 8 1mum thick, and patterned in a rectangular shape of 2mumX10mum. Then, with the resist 8 as a mask the aluminum is removed by etching with phosphoric acid. In this case, since the thickness of the aluminum is then 0.05mum, the side etching of the aluminum is less, and can be formed substantially in the same size as that of the resist. Then, the tungsten is removed by etching by a dry etching method with mixture gas of CF4 and O2.
|
