Method for transferring a layer from a single-crystal substrate

Patent metadata

Field	Value
Publication number	US-9768057-B2
Application number	US-201615159646-A
Country	US
Kind code	B2
Filing date	May 19, 2016
Priority date	May 28, 2015
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

A method for transferring a layer from a single-crystal substrate, called a donor substrate, onto a receiver substrate, includes supplying the single-crystal donor substrate, the substrate having a notch oriented in a first direction of the crystal and a weakness region bounding the layer to be transferred, bonding of the single-crystal donor substrate onto the receiver substrate, the main surface of the donor substrate opposite to the weakness region with respect to the layer to be transferred being at the bonding interface, and detachment of the donor substrate along the weakness region. In the method, the donor substrate has, on the main surface bonded to the receiver substrate, an array of atomic steps extending essentially in a second direction of the crystal different from the first direction.

First claim

What is claimed is:

1. A method for transferring a layer from a single-crystal substrate, called a donor substrate, onto a receiver substrate, comprising:
supplying the single-crystal donor substrate, the donor substrate having a notch oriented in a first direction of the crystal of the donor substrate and a weakness region bounding the layer to be transferred,
bonding the single-crystal donor substrate onto the receiver substrate, a main surface of the donor substrate opposite to the weakness region with respect to the layer to be transferred being at the bonding interface,
detaching the donor substrate along the weakness region, thus transferring the layer to be transferred onto the receiver substrate, the transferred layer defining a free surface opposite the main surface bonded to the receiver substrate,
wherein the donor substrate is obtained by slicing a section of single crystal ingot, the slicing being made with an inclination only in a second direction of the crystal of the ingot different from the first direction, and the donor substrate has, on the main surface bonded to the receiver substrate and on the free surface opposite the main surface, an array of atomic steps extending essentially in the second direction of the crystal of the donor substrate different from the first direction.

2. The method of claim 1 , wherein a density of atoms in the second direction is greater than a density of atoms in the first direction.

3. The method of claim 1 , wherein the steps of the array of steps have at least twice a length in the second direction of the crystal than in another direction perpendicular to the second direction.

4. The method of claim 1 , wherein a thickness of the transferred layer is greater than or equal to 150 nm.

5. The method of claim 1 , wherein the donor substrate has a crystal lattice with a centered cubic, face-centered cubic or diamond structure.

6. The method of claim 1 , wherein a main surface of the section of the single crystal ingot is in a plane with a normal direction <100>, the notch is oriented with an angle of 45° with respect to a direction <110> and the slicing is made with an inclination only in the direction <110>, in such a manner that the atomic steps extend essentially in the direction <110>.

7. The method of claim 1 , wherein the donor substrate is made of silicon.

Assignees

• Soitec Silicon On Insulator

Inventors

• Ecarnot Ludovic
• Daval Nicolas
• Mohamed Nadia Ben
• Boedt Francois
• David Carole
• Guerin Isabelle

Classifications

• H10P90/1916 Primary

  with separation or delamination along an ion implanted layer, e.g. Smart-cut · CPC title

• H10P90/00

  Preparation of wafers not covered by a single main group of this subclass, e.g. wafer reinforcement · CPC title

• H10W10/181

  Semiconductor-on-insulator [SOI] isolation regions, e.g. buried oxide regions of SOI wafers · CPC title

• H10P90/1914 Primary

  using bonding · CPC title

• B28D5/00

  Fine working of gems, jewels, crystals, e.g. of semiconductor material; apparatus or devices therefor (working by grinding or polishing B24; for artistic purposes B44B) · CPC title