Method for forming a thin dielectric layer on a substrate

• US 5,268,311 A
• Filed: 04/25/1991
• Issued: 12/07/1993
• Est. Priority Date: 09/01/1988
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Hagmann, Dieter, Wildau, Hans-Jurgen, Euen, Wolfgang
• Primary Examiner(s): Hearn, Brian E.
• Assistant Examiner(s): Fleck, Linda J.
• Application Number:
  US07/691,256
• Time in Patent Office: 957 Days
• Field of Search: 437/24, 437/28, 437/29, 437/235, 437/241
• US Class Current: 438/515
• 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 21/28194 by deposition, e.g. evaporation, ALD, CVD, sputtering, laser deposition H01L21/28202 takes precedence
• CPC Class Codes: H01L 21/28211 in a gaseous ambient using an oxygen or a water vapour, e.g. RTO, possibly through a layer H01L21/28194 and H01L21/28202 take precedence
• CPC Class Codes: H01L 21/2822 with substrate doping, e.g. N, Ge, C implantation, before formation of the insulator
• CPC Class Codes: H01L 21/3105 After-treatment

Abstract

Disclosed is a thin dielectric inorganic layer overlaying a substrate, and having a thickness of≦ about 20 nm and a defect density of≦ about 0.6 defects/cm² determined by BV measurements.

Also disclosed is a method of forming such a layer, according to which a layer having the desired composition and thickness is formed on a substrate, followed by an ion implantation into the substrate through the layer with a dose of≧ about 10¹⁵ ions/cm² and a subsequent anneal at a temperature of≧ about 500° C. for a predetermined time.

Claims

1. A method for forming a dielectric inorganic layer, comprising the steps of:

forming on a substrate a dielectric inorganic layer having a thickness ≦

about 20 nm, said layer consisting essentially of a material selected from the group consisting of silicon dioxide, silicon monoxide and silicon nitride, implating ions into said substrate through said layer with a does of ≦

about 10¹⁵ /cm², wherein said ions are implanted with an energy such that the projected range exceeds the thickness of said layer, and annealing said layer in an inert atmosphere at a temperature of ≧

about 500°

C. for a predetermined time, so as to produce a resulting layer having a defect density of ≦

0.6 defects/cm².

2. The method of claim 1, wherein said ions are selected from the group consisting of boron, phosphorous, arsenic, silicon, argon and BF₂.

3. The method of claim 1, wherein said dielectric inorganic layer is formed by wet or dry thermal oxidation, cathode sputtering or chemical vapor deposition.