METHOD FOR PRODUCING HYPERTHERMAL HYDROGEN MOLECULES AND USING SAME FOR SELECTIVELY BREAKING C-H AND/OR Si-H BONDS OF MOLECULES AT OR ON SUBSTRATE SURFACES.

摘要

A method for producing hyperthermal molecular hydrogen is disclosed and use of same for selectively breaking C-H or Si-H bonds without breaking other bonds are disclosed. A hydrogen plasma is maintained and protons are extracted with an electric field to accelerate them to an appropriate kinetic energy. The protons enter into a drift zone to collide with molecular hydrogen in gas phase. The cascades of collisions produce a high flux of hyperthermal molecular hydrogen with a flux many times larger than the flux of protons extracted from the hydrogen plasma. The nominal flux ratio of hyperthermal molecular hydrogen to proton is controlled by the hydrogen pressure in the drift zone, and by the length of the drift zone. The extraction energy of the protons is shared by these hyperthermal molecules so that average energy of the hyperthermal molecular hydrogen is controlled by extraction energy of the protons and the nominal flux ratio. Since the hyperthermal molecular hydrogen projectiles do not carry any electrical charge, the flux of hyperthermal hydrogen can be used to engineer surface modification of both electrical insulating products and conductive products. When this method of generating a high flux of hyperthermal molecular hydrogen is applied to bombard organic precursor molecules (or silicone, or silane molecules) with desirable chemical functionality/functionalities on a substrate, the C-H or Si-H bonds are thus cleaved preferentially due to the kinematic selectivity of energy deposition from the hyperthermal hydrogen projectiles to the hydrogen atoms in the precursor molecules. The induced cross-linking reactions produce a stable molecular layer having a controllable degree of cross-linking and retaining the desirable chemical functionality/functionalities of the precursor molecules.