Intermolecular, Inc.

Elpida Memory, Inc.

Nobumichi Fuchigami

Pragati Kumar

Hanhong Chen

Prashant B Phatak

Sandra Guy Malhotra

Imran Hashim

Sunil Shanker

Hiroyuki Ode

Wim Deweerd

Edward L Haywood

Karthik Ramani

Tony P Chiang

Indranil De

Monica Sawkar Mathur

ALD processing techniques for forming non-volatile resistive-switching memories are described. In one embodiment, a method includes forming a first electrode on a substrate, maintaining a pedestal temperature for an atomic layer deposition (ALD) process of less than 100&#xb0; Celsius, forming at least one metal oxide layer over the first electrode, wherein the forming the at least one metal oxide layer is performed using the ALD process using a purge duration of less than 20 seconds, and forming a second electrode over the at least one metal oxide layer.

ALD processing techniques for forming non-volatile resistive switching memories

This disclosure provides (a) methods of making an oxide layer (e.g., a dielectric layer) based on yttrium and titanium, to have a high dielectric constant and low leakage characteristic and (b) related devices and structures. An oxide layer having both yttrium and titanium may be fabricated either as an amorphous oxide or as an alternating series of monolayers. In several embodiments, the oxide is characterized by a yttrium contribution to total metal that is specifically controlled. The oxide layer can be produced as the result of a reactive process, if desired, via either a PVD process or, alternatively, via an atomic layer deposition process that employs specific precursor materials to allow for a common process temperature window for both titanium and yttrium reactions.

Yttrium and titanium high-k dielectric films

A method for fabricating a dynamic random access memory (DRAM) capacitor stack is disclosed wherein the stack includes a first electrode, a dielectric layer, and a second electrode. The first electrode is formed from a conductive binary metal compound and the conductive binary metal compound is annealed in a reducing atmosphere to promote the formation of a desired crystal structure. The binary metal compound may be a metal oxide. Annealing the metal oxide (i.e. molybdenum oxide) in a reducing atmosphere may result in the formation of a first electrode material (i.e. MoO) with a rutile-phase crystal structure. This facilitates the formation of the rutile-phase crystal structure when TiOis used as the dielectric layer. The rutile-phase of TiOhas a higher k value than the other possible crystal structures of TiOresulting in improved performance of the DRAM capacitor.

Method for fabricating a DRAM capacitor

This disclosure provides a method of fabricating a semiconductor stack and associated device such as a capacitor and DRAM cell. In particular, a bottom electrode upon which a dielectric layer is to be grown may have a ruthenium-based surface. Lattice matching of the ruthenium surface with the dielectric layer (e.g., titanium oxide, strontium titanate or barium strontium titanate) helps promote the growth of rutile-phase titanium oxide, thereby leading to higher dielectric constant and lower effective oxide thickness. The ruthenium-based material also provides a high work function material, leading to lower leakage. To mitigate nucleation delay associated with the use of ruthenium, an adherence or glue layer based in titanium may be employed. A pretreatment process may be further employed so as to increase effective capacitor plate area, and thus promote even further improvements in dielectric constant and effective oxide thickness ('EOT').

Fabrication of semiconductor stacks with ruthenium-based materials

This disclosure provides (a) methods of making an oxide layer (e.g., a dielectric layer) based on titanium oxide, to suppress the formation of anatase-phase titanium oxide and (b) related devices and structures. A metal-insulator-metal ('MIM') stack is formed using an ozone pretreatment process of a bottom electrode (or other substrate) followed by an ALD process to form a TiOdielectric, rooted in the use of an amide-containing precursor. Following the ALD process, an oxidizing anneal process is applied in a manner is hot enough to heal defects in the TiOdielectric and reduce interface states between TiOand electrode; the anneal temperature is selected so as to not be so hot as to disrupt BEL surface roughness. Further process variants may include doping the titanium oxide, pedestal heating during the ALD process to 275-300 degrees Celsius, use of platinum or ruthenium for the BEL, and plural reagent pulses of ozone for each ALD process cycle. The process provides high deposition rates, and the resulting MIM structure has substantially no x-ray diffraction peaks associated with anatase-phase titanium oxide.

Titanium based high-K dielectric films

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Sunnyvale, CA, United States of America

Nobumichi Fuchigami