Crystallization processing for semiconductor applications

• US 8,313,965 B2
• Filed: 11/23/2010
• Issued: 11/20/2012
• Est. Priority Date: 11/30/2009
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Moffatt, Stephen
• Primary Examiner(s): Maldonado, Julio J
• Assistant Examiner(s): SHOOK, DANIEL P
• Application Number:
  US12/953,103
• Publication Number:
  US 20110129959A1
• Time in Patent Office: 728 Days
• Field of Search: 438/36, 438/89, 438/166, 438/797, 438/799, 257/E21.347
• US Class Current: 438/36
• CPC Class Codes: C30B 13/24 using electromagnetic waves
• CPC Class Codes: C30B 29/403 AIII-nitrides
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02568 Chalcogenide semiconducting materials not being oxides, e.g. ternary compounds
• CPC Class Codes: H01L 21/02686 Pulsed laser beam
• CPC Class Codes: H01L 21/2636 for heating, e.g. electron beam heating
• CPC Class Codes: H01L 21/268 using electromagnetic radiation, e.g. laser radiation
• CPC Class Codes: H01L 29/685 Hi-Lo semiconductor devices, e.g. memory devices
• CPC Class Codes: H01L 31/1872 Recrystallisation
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells
• CPC Class Codes: Y02E 10/548 Amorphous silicon PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A method and apparatus for forming a crystalline semiconductor layer on a substrate are provided. A semiconductor layer is formed by vapor deposition. A pulsed laser melt/recrystallization process is performed to convert the semiconductor layer to a crystalline layer. Laser, or other electromagnetic radiation, pulses are formed into a pulse train and uniformly distributed over a treatment zone, and successive neighboring treatment zones are exposed to the pulse train to progressively convert the deposited material to crystalline material.

Claims

1. A method of reorganizing the structure of a solid material, comprising:

exposing a treatment zone of the solid material to a first plurality of energy pulses to progressively melt the treatment zone, forming a molten area; and

progressively recrystallizing the molten area by directing a second plurality of energy pulses to the molten area to form a crystalline solid, wherein exposing the treatment zone to the first plurality of energy pulses comprises exposing the treatment zone to a plurality of laser pulses, the first laser pulse having an intensity lower than one or more of the succeeding laser pulses.

2. The method of claim 1, wherein the first laser pulse has an intensity lower than the succeeding laser pulses.

3. A method of forming a memory device, comprising:

forming a first conductive layer on a substrate;

forming a polycrystalline or monocrystalline semiconductor layer on the substrate by a process comprising;

depositing a semiconductor layer on the substrate;

progressively melting the semiconductor layer by exposing the semiconductor layer to a first plurality of energy pulses, forming a molten semiconductor layer; and

recrystallizing the molten semiconductor layer by exposing the molten semiconductor layer to a second plurality of energy pulses; and

forming a second conductive layer on the substrate, wherein each pulse of the first plurality of enemy pulses is designed to melt a portion of the semiconductor material and wherein the first plurality of energy pulses are laser pulses, wherein a first laser pulse has an intensity lower than the other laser pulses.

4. A method of forming a photonic device, comprising:

forming a compound semiconductor layer over a ceramic substrate; and

crystallizing the compound semiconductor layer by a process comprising;

directing pulses of energy toward the compound semiconductor layer, progressively melting the compound semiconductor layer to form a molten layer; and

directing pulses of energy toward the molten layer while crystallizing the molten layer to form a crystalline compound semiconductor layer, wherein the directing pulses of energy toward the compound semiconductor layer comprises directing a plurality of laser pulses toward the compound semiconductor layer, each pulse having energy selected to melt a portion of the compound semiconductor layer, and progressing a melt front through the compound semiconductor layer and wherein the plurality of laser pulses comprises a first pulse having an intensity lower than the intensity of the other pulses.