Method of forming non-conformal layers
First Claim
1. A method for depositing a film on a semiconductor substrate, the method comprising:
- providing a substrate with a surface comprising regions with different levels of accessibility;
providing a sequence of at least two different reactants in temporally separated and alternating reactant pulses, wherein at least one of the at least two different reactants is provided through a showerhead or otherwise provided in that it impinges vertically on the substrate;
selecting plasma-enhanced atomic layer deposition (PEALD) conditions to achieve self-saturation and self-limiting atomic layer deposition (ALD) mode deposition on the most accessible regions on the substrate surface and depletion effects in less accessible regions on the substrate surface; and
exposing the semiconductor substrate to the sequence of the reactant pulses with the selected temporal separations and durations to deposit the film.
2 Assignments
0 Petitions
Accused Products
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
-
Citations
40 Claims
-
1. A method for depositing a film on a semiconductor substrate, the method comprising:
-
providing a substrate with a surface comprising regions with different levels of accessibility;
providing a sequence of at least two different reactants in temporally separated and alternating reactant pulses, wherein at least one of the at least two different reactants is provided through a showerhead or otherwise provided in that it impinges vertically on the substrate;
selecting plasma-enhanced atomic layer deposition (PEALD) conditions to achieve self-saturation and self-limiting atomic layer deposition (ALD) mode deposition on the most accessible regions on the substrate surface and depletion effects in less accessible regions on the substrate surface; and
exposing the semiconductor substrate to the sequence of the reactant pulses with the selected temporal separations and durations to deposit the film. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method of controlling conformality of a deposited film on a semiconductor substrate, the method comprising:
-
providing a substrate with a plurality of openings at a surface thereof;
alternately and sequentially supplying pulses of at least two different reactants to the substrate; and
selectively activating at least one of the two different reactants in pulses, wherein selectively activating is controlled to have a depletion effect within the openings to less than fully cover surfaces of the openings. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
-
-
27. A method of controlling conformality of a deposited film on a semiconductor substrate comprising a plurality of openings at a surface thereof, the method comprising:
alternately and sequentially contacting a substrate 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 such that the deposited film less than fully covers surfaces of the openings. - View Dependent Claims (28, 29, 30, 31, 32)
-
33. A method of partially lining a trench in a substrate in a reaction space by an atomic layer deposition (ALD) reaction, the method comprising:
-
contacting the substrate with a saturating dose of a first reactant to form a monolayer of the first reactant over the surfaces of the trench;
providing an under-saturating dose of a second reactant; and
contacting the substrate with the entire under-saturating dose of the second reactant, such that the second reactant reacts with a film formed by the first reactant to a desired depth within the trench. - View Dependent Claims (34, 35)
-
-
36. An apparatus for depositing a thin film on a substrate comprising a reaction chamber and a dosage control mechanism for providing a particular dose of a reactant to the reaction chamber, the dosage control mechanism comprising:
-
a reactant source vessel;
a dosage chamber with a controlled volume in communication with the reactant source vessel and the reaction chamber, wherein the dosage chamber has a first temperature and the reaction chamber has a second temperature; and
a control system configured to separately control the first temperature and the second temperature. - View Dependent Claims (37, 38, 39, 40)
-
Specification