Post thermal treatment methods of forming high dielectric layers over interfacial layers in integrated circuit devices

• US 20060115993A1
• Filed: 01/17/2006
• Published: 06/01/2006
• Est. Priority Date: 09/10/2002
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Jong-ho, Doh, Seok-Joo, Lee, Nae-in, Jung, Hyung-suk, Kim, Yun-seok
• Granted Patent: US 7,494,940 B2
• Time in Patent Office: Days
• US Class Current: 438/762
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02181 the material containing hafnium, e.g. HfO2
• CPC Class Codes: H01L 21/02189 the material containing zirconium, e.g. ZrO2
• CPC Class Codes: H01L 21/02192 the material containing at least one rare earth metal element, e.g. oxides of lanthanides, scandium or yttrium
• CPC Class Codes: H01L 21/022 the layer being a laminate, i.e. composed of sublayers, e.g. stacks of alternating high-k metal oxides adhesion layers or buffer layers H01L21/02304, H01L21/02362
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02323 introduction of oxygen
• CPC Class Codes: H01L 21/02329 introduction of nitrogen
• CPC Class Codes: H01L 21/02337 treatment by exposure to a gas or vapour
• 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 21/28202 in a nitrogen-containing ambient, e.g. nitride deposition, growth, oxynitridation, NH3 nitridation, N2O oxidation, thermal nitridation, RTN, plasma nitridation, RPN
• 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 21/3143 composed of alternated layers or of mixtures of nitrides and oxides or of oxinitrides, e.g. formation of oxinitride by oxidation of nitride layers
• CPC Class Codes: H01L 21/31616 Deposition of Al2O3
• CPC Class Codes: H01L 21/31641 Deposition of Zirconium oxides, e.g. ZrO2
• CPC Class Codes: H01L 21/31645 Deposition of Hafnium oxides, e.g. HfO2
• CPC Class Codes: H01L 21/31662 of silicon in uncombined form
• CPC Class Codes: H01L 28/56 the dielectric comprising two or more layers, e.g. comprising buffer layers, seed layers, gradient layers
• 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

Abstract

High dielectric layers formed from layers of hafnium oxide, zirconium oxide, aluminum oxide, yttrium oxide, and/or other metal oxides and silicates disposed on silicon substrates or ozone oxide layers over silicon substrates may be nitrided and post thermally treated by oxidation, annealing, or a combination of oxidation and annealing to form high dielectric layers having superior mobility and interfacial characteristics.

Claims

1. A method for forming a high dielectric layer of a semiconductor device, comprising:

forming an ozone oxide layer over a silicon substrate;

forming a high dielectric layer on said ozone oxide layer, wherein said high dielectric layer comprises at least one layer selected from the group consisting of a hafnium oxide layer, a zirconium oxide layer, and a Group 3 metal oxide layer;

nitriding said silicon substrate and said high dielectric layer on said silicon substrate; and

then oxidizing the silicon substrate and high dielectric layer.

2. The method of claim 1 wherein forming said ozone oxide layer over said silicon substrate comprises flushing said silicon substrate with ozone in situ.

3. The method of claim 1 wherein forming said ozone oxide layer over said silicon substrate comprises forming said ozone oxide layer using atom layer deposition.

4. The method of claim 1 wherein forming said ozone oxide layer over said silicon substrate comprises forming said ozone oxide layer using chemical vapor deposition.

5. The method of claim 1 wherein forming said ozone oxide layer over said silicon substrate comprises forming said ozone oxide layer at a temperature between about 320°

C. and about 450°

C.

6. The method of claim 1 wherein said ozone oxide layer comprises an ozone oxide layer having a thickness of about 8 Å

or less.

7. The method of claim 1 wherein the Group 3 metal oxide layer is selected from the group consisting of an aluminum oxide layer and a yttrium oxide layer.

8. The method of claim 1 wherein the high dielectric layer further comprises at least one layer selected from the group consisting of a hafnium silicate layer, a zirconium silicate layer, and an aluminum silicate layer.

9. The method of claim 1 wherein said nitriding is performed using a nitriding process selected from the group consisting of a nitrogen plasma treatment process, a thermal treatment in a nitrogen atmosphere process, and a process comprising forming a nitrogen layer over the high dielectric layer and thermally treating the formed nitrogen layer.

10. The method of claim 1, wherein said oxidizing the silicon substrate and high dielectric layer comprises wet oxidizing the silicon substrate and high dielectric layer.

11. The method of claim 1, wherein said oxidizing the silicon substrate and high dielectric layer comprises dry oxidizing the silicon substrate and high dielectric layer.

12. The method of claim 1, wherein said oxidizing the silicon substrate and high dielectric layer comprises oxidizing the silicon substrate and high dielectric layer with an oxidizing agent selected from the group consisting of ozone, radical oxygen, and oxygen plasma.