Method of making a free-standing diamond film with reduced bowing

Abstract

A method for producing free-standing diamond film having a surface area of at least 1000 square millimeters includes the following steps: providing a substrate; depositing, on the substrate, by chemical vapor deposition, a first layer of diamond over a surface area of at least 1000 square millimeters, and to a first thickness, the first layer being deposited at a first deposition rate; depositing, on the first layer, a second layer of diamond, over a surface area of at least 1000 square millimeters, and to a second thickness, the second layer being deposited at a second deposition rate; and releasing the diamond from the substrate; the second deposition rate being as lest twice as high as the first deposition rate, and the first thickness being sufficiently thick to prevent the released diamond from bowing by more than a given distance.

Dependencies are inferred from the claim text.