Back to results
US 12,217,968 B2Granted
Atomic layer etching for smoothing of arbitrary surfaces
AssigneeCalifornia Institute of Technology
InventorHarold Frank Greer
Life of this patent
Estimating the term…
Abstract
A method for etching a surface including obtaining a substrate comprising a material; reacting a surface of a substrate with a reactant, comprising a gas or a plasma, to form a reactive layer on the substrate, the reactive layer comprising a chemical compound including the reactant and the material; and wet etching or dissolving the reactive layer with a liquid wet etchant of solvent that selectively etches or dissolves the reactive layer but not the substrate.
Claims28
An apparatus:
- a reactor tool comprising a source of a reactant for reacting with a surface of a substrate so as to form a reactive layer on the substrate, wherein the reactant comprises is generated by a plasma, the substrate comprises a material comprising a semiconductor, a metal, or a dielectric, and the reactive layer comprises a chemical compound including the reactant and the material;
- and
- an etching tool comprising a source of a liquid wet etchant for removing the chemical compound;
- and
- a computer tool comprising a non-transitory computer readable medium storing a plurality of instructions, the plurality of instructions comprising:
- outputting the reactant in the reactor tool,
- transferring the substrate between the reactor tool and the etching tool, and
- outputting the liquid wet etchant in the etching tool to remove the chemical compound at a higher rate than the material so as to smoothen the surface of the substrate and form the surface having a root mean square surface roughness of less than 1 nm.
5 more elements
An apparatus, comprising:
- a source of a reactant reacting with a surface of a substrate so as to form a reactive layer on the substrate, wherein the reactant is in gaseous form or is generated by a plasma, the substrate comprises a material, and the reactive layer comprises a chemical compound including the reactant and the material;
- a source of a treatment that removes the chemical compound at a higher rate than the material;
- and
- a computer programmable to:
- (a) instruct output of the reactant so as to form the reactive layer;
- (b) instruct performance of the treatment, and
- (c) instruct a repeat of steps (a) and (b) so as to perform a first cycle and a second cycle each comprising the step (a) and the step (b), wherein:
- the second cycle forms the reactive layer having a thickness that is thinner as compared to the reactive layer formed in the first cycle, so that the treatment in the second cycle removes the reactive layer with a finer resolution as compared to in the first cycle.
5 more elements
An apparatus, comprising:
- a reactor tool for reacting a reactant with a surface of a substrate so as to form a reactive layer on the substrate, wherein the reactant comprises a plasma, and the reactive layer comprises a chemical compound including the reactant and the material;
- an etching tool for applying a treatment for removing the chemical compound at a higher rate than the material;
- a transfer chamber for transferring the substrate between the reactor tool and the etching tool;
- a computer programmable to instruct the apparatus to:
- (a) instruct the reactor tool to form the reactive layer and at least perform:
- a cleaning of the surface of the substrate prior to forming the reactive layer, or activating of the reactive layer so as to make the reactive layer more amenable for the removing;
- (b) repeat the step (a) in a presence of the reactive layer previously formed;
- and
- (c) instruct the etching tool to perform the treatment of the reactive layer to remove the reactive layer, such that the substrate is smoother after the reactive layer is removed.
6 more elements
An apparatus comprising:
- a reactor tool comprising a source of a reactant, wherein the reactor tool is configured to ignite a plasma comprising the reactant;
- an etching tool comprising a source of a liquid wet etchant;
- and
- a substrate with a reactive layer disposed in the etching tool, wherein:
- the substrate comprises a material comprising a semiconductor, a metal, or a dielectric,
- the reactive layer was formed by reacting a surface of the substrate with the reactant and the plasma in the reactor tool,
- the reactive layer comprises a chemical compound including the reactant and the material, and
- the liquid wet etchant is configured to remove the chemical compound at a higher rate than the material in order to smoothen the surface of the substrate and to form the surface having a root mean square surface roughness of less than 1 nm.
5 more elements
Dependencies are inferred from the claim text.