Semiconductor devices comprising nitrogen-doped gate dielectric

• US 9,922,885 B1
• Filed: 11/30/2016
• Issued: 03/20/2018
• Est. Priority Date: 11/30/2016
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Moriwaki, Yoshikazu
• Primary Examiner(s): Hossain, Moazzam
• Assistant Examiner(s): Kilpatrick, Warren H
• Application Number:
  US15/365,126
• Time in Patent Office: 475 Days
• Field of Search: 257369
• CPC Class Codes: H01L 21/28158 Making the insulator
• CPC Class Codes: H01L 21/28185 with a treatment, e.g. annealing, after the formation of the gate insulator and before the formation of the definitive gate conductor
• CPC Class Codes: H01L 21/31155 by ion implantation
• CPC Class Codes: H01L 21/823842 gate conductors with different gate conductor materials or different gate conductor implants, e.g. dual gate structures
• CPC Class Codes: H01L 21/823857 with a particular manufacturing method of the gate insulating layers, e.g. different gate insulating layer thicknesses, particular gate insulator materials or particular gate insulator implants
• CPC Class Codes: H01L 27/092 complementary MIS field-effect transistors
• CPC Class Codes: H01L 29/42364 characterised by the insulating layer, e.g. thickness or uniformity H01L29/42324 and H01L29/4234 take precedence
• CPC Class Codes: H01L 29/49 Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET H01L29/435 takes precedence
• CPC Class Codes: H01L 29/4958 with a multiple layer structure
• CPC Class Codes: H01L 29/512 the variation being parallel to the channel plane
• CPC Class Codes: H01L 29/513 the variation being perpendicular to the channel plane
• CPC Class Codes: H01L 29/517 the insulating material comprising a metallic compound, e.g. metal oxide, metal silicate H01L29/518 takes precedence
• CPC Class Codes: H01L 29/518 the insulating material containing nitrogen, e.g. nitride, oxynitride, nitrogen-doped material
• CPC Class Codes: H01L 29/6656 using multiple spacer layers, e.g. multiple sidewall spacers
• CPC Class Codes: H01L 29/7833 with lightly doped drain or source extension, e.g. LDD MOSFET's; DDD MOSFET's for thin film transistors H01L29/78618

Abstract

Some embodiments include semiconductor devices having first transistors of a first channel type and having second transistors of a second channel type. The first transistors include a first gate electrode, a first nitrogen-doped gate dielectric layer and a first high-k material. The second transistors include a second gate electrode, a second nitrogen-doped gate dielectric layer and a second high-k material. The second nitrogen-doped gate dielectric layer is doped with nitrogen to a different peak concentration than the first nitrogen-doped gate dielectric layer. Some embodiments include methods of forming PMOS and NMOS transistors having nitrogen-doped gate dielectric material.

Claims

1. A semiconductor device comprising:

a PMOS transistor having a first nitrogen-doped gate dielectric layer doped with nitrogen to a first concentration;

an NMOS transistor having a second nitrogen-doped gate dielectric layer doped with nitrogen to a second concentration;

wherein the second concentration is at least about 30% greater than the first concentration;

wherein the first and second nitrogen-doped gate dielectric layers both comprise silicon oxide; and

wherein the PMOS transistor comprises a first oxide and a second oxide over the first nitrogen-doped gate dielectric layer, and comprises a metal-containing composition over the second oxide; and

wherein the NMOS transistor comprises the same metal-containing composition as the PMOS transistor, and comprises only first oxide between the metal-containing composition and the second nitrogen-doped gate dielectric layer.

2. The semiconductor device according to claim 1, wherein the metal-containing composition is a metal nitride, the first oxide is hafnium oxide and the second oxide is aluminum oxide.