# US 8,542,523 B2 · Method for fabricating a DRAM capacitor having increased thermal and chemical stability

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,542,523 B2
- Document ID: US8542523B2
- Status: Granted
- Kind: B2
- Application number: 13/738,855
- Filed: 2013-01-10
- Published: 2013-05-16
- Granted: 2013-09-24
- Earliest claimed: 2011-05-13
- Assignees: Intermolecular, Inc.; Elpida Memory, Inc.
- Applicants: Intermolecular Inc.
- Inventors: Karthik Ramani; Wim Y. Deweerd; Hiroyuki Ode
- Web page: https://patentgrep.com/patent/US8542523B2

## CPC

- H10D 1/694: {comprising noble metals or noble metal oxides}
- H10D 1/47: Resistors having no potential barriers
- H10N 70/066: {by filling of openings, e.g. damascene method}
- H10N 70/231: {based on solid-state phase change, e.g. between amorphous and crystalline phases, Ovshinsky effect}
- H10N 70/253: {having three or more electrodes, e.g. transistor-like devices}
- H10N 70/821: {Device geometry}
- H10N 70/8613: {Heating or cooling means other than resistive heating electrodes, e.g. heater in parallel}
- H10N 70/8828: {Tellurides, e.g. GeSbTe}
- H10N 70/884: {based on at least one element of group IIIA, IVA or VA, e.g. elemental or compound semiconductors (compounds of sulfur, selenium or tellurium, e.g. chalcogenides H10N70/882; oxides or nitrides H10N70/883)}
- Y10S 977/754: Dendrimer, i.e. serially branching or "tree-like" structure
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

## Abstract

A method for fabricating a dynamic random access memory (DRAM) capacitor includes forming a first electrode film. The first electrode film comprises a conductive binary metal compound and a dopant. The dopant may have a uniform or non-uniform concentration within the first electrode film. A high-k dielectric film is formed over the first electrode film. A second electrode film is formed over the dielectric film. The second electrode film comprises a conductive binary metal compound and a dopant. The dopant may have a uniform or non-uniform concentration within the second electrode film. The dopants and their distribution are chosen so that the crystal structure of the surface of the electrode is not degraded if the electrode is to be used as a templating structure for subsequent layer formation. Additionally, the dopants and their distribution are chosen so that the work function of the electrodes is not degraded.

## Claims

### Claim 1

A semiconductor layer stack comprising:
a first electrode layer formed on a substrate, the first electrode layer comprising a first electrode material and a dopant;
a dielectric layer formed on the first electrode layer; and
a second electrode layer formed on the dielectric layer.

### Claim 2 (depends on 1)

The semiconductor layer stack of claim 1, wherein the first electrode layer comprises one of conductive metal oxides, conductive metal silicides, conductive metal nitrides, or combinations thereof.

### Claim 3 (depends on 2)

The semiconductor layer stack of claim 2, wherein the conductive metal oxide comprises one of molybdenum oxide, ruthenium oxide, rhenium oxide, tungsten oxide, rhodium oxide, iridium oxide, chromium oxide, manganese oxide, tin oxide, cobalt oxide, nickel oxide, or combinations thereof.

### Claim 4 (depends on 3)

The semiconductor layer stack of claim 3 wherein the conductive metal oxide is molybdenum oxide.

### Claim 5 (depends on 1)

The semiconductor layer stack of claim 1 wherein the dopant comprises at least one of Si, Al, Ge, or a transition metal.

### Claim 6 (depends on 1)

The semiconductor layer stack of claim 1 wherein the dopant has a non-uniform concentration gradient throughout the first electrode layer.

### Claim 7 (depends on 6)

The semiconductor layer stack of claim 6 wherein the concentration of the dopant is lowest at the surface of the first electrode layer that is in contact with the dielectric layer.

### Claim 8 (depends on 1)

The semiconductor layer stack of claim 1 wherein the second electrode layer further comprises a second electrode material and a dopant.

### Claim 9 (depends on 8)

The semiconductor layer stack of claim 8, wherein the second electrode material comprises one of conductive metal oxides, conductive metal silicides, conductive metal nitrides, or combinations thereof.

### Claim 10 (depends on 9)

The semiconductor layer stack of claim 9, wherein the conductive metal oxide comprises one of molybdenum oxide, ruthenium oxide, rhenium oxide, tungsten oxide, rhodium oxide, iridium oxide, chromium oxide, manganese oxide, tin oxide, cobalt oxide, nickel oxide, or combinations thereof.

### Claim 11 (depends on 10)

The semiconductor layer stack of claim 10 wherein the conductive metal oxide is molybdenum oxide.

### Claim 12 (depends on 8)

The semiconductor layer stack of claim 8 wherein the dopant in the second electrode material comprises one of Si, Al, Ge, or a transition metal.

### Claim 13 (depends on 8)

The semiconductor layer stack of claim 8 wherein the dopant in the second electrode material has a non-uniform concentration gradient throughout the second electrode material.

### Claim 14 (depends on 13)

The semiconductor layer stack of claim 13 wherein the concentration of the dopant is lowest at the surface of the second electrode material that is in contact with the dielectric layer.