Method of forming non-conformal layers

US7608549B2 · kind B2 · utility

Assignee

• ASM America, Inc. · US

Inventors

• Sebastian E. Van Nooten · Bilthoven, NL
• Jan Willem Maes · Wilrijk, BE
• Steven Marcus · Tempe, US
• Glen Wilk · Scottsdale, US
• Petri Raisanen · Gilbert, US
• Kai-Erik Elers · Helsinki, FI

Key dates

• Filing date: Mar 13, 2006
• Grant date: Oct 27, 2009
• Expiry date: Apr 28, 2027

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/0228
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

In one aspect, non-conformal layers are formed by variations of plasma enhanced atomic layer deposition, where one or more of pulse duration, separation, RF power on-time, reactant concentration, pressure and electrode spacing are varied from true self-saturating reactions to operate in a depletion-effect mode. Deposition thus takes place close to the substrate surface but is controlled to terminate after reaching a specified distance into openings (e.g., deep DRAM trenches, pores, etc.). Reactor configurations that are suited to such modulation include showerhead, in situ plasma reactors, particularly with adjustable electrode spacing. In another aspect, alternately and sequentially contacting a substrate, the substrate including openings, with at least two different reactants, wherein an under-saturated dose of at least one of the reactants has been predetermined and the under-saturated dose is provided uniformly across the substrate surface, deposits a film that less than fully covers surfaces of the openings, leading to depletion effects in less accessible regions on the substrate surface.