Method of manufacturing semiconductor device having optical devices

• US 8,394,705 B2
• Filed: 05/19/2010
• Issued: 03/12/2013
• Est. Priority Date: 12/09/2009
• Status: Expired due to Fees

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Kim, In Gyoo, Park, Dae Seo, Hong, Jun Taek, Kim, Gyungock
• Primary Examiner(s): Toledo, Fernando L
• Assistant Examiner(s): Shamsuzzaman, Mohammed
• Application Number:
  US12/783,216
• Publication Number:
  US 20110136318A1
• Time in Patent Office: 1,028 Days
• Field of Search: 438/31, 438424-427, 257/509, 257/647
• US Class Current: 438/425
• CPC Class Codes: G02B 6/132 by deposition of thin films
• CPC Class Codes: G02B 6/136 by etching
• CPC Class Codes: G02F 1/212 Mach-Zehnder type
• CPC Class Codes: G02F 1/2257 the optical waveguides being made of semiconducting material
• CPC Class Codes: G02F 2203/15 involving resonance effects, e.g. resonantly enhanced interaction
• CPC Class Codes: H01L 27/1203 the substrate comprising an insulating body on a semiconductor body, e.g. SOI three-dimensional layout H01L27/0688

Abstract

Provided is a method of manufacturing a semiconductor device. According to the method, a first buried oxide layer is formed in the semiconductor substrate in a first region, such that a first semiconductor layer is defined on the first buried oxide layer. An active portion is defined by forming a trench in the semiconductor substrate in a second region. A capping semiconductor pattern is formed on a top surface and an upper portion of a sidewall of the active portion. An oxide layer is formed by oxidizing the capping semiconductor pattern and an exposed lower portion of the sidewall of the active portion, such that the oxide layer surrounds a non-oxidized portion of the active portion. The non-oxidized portion of the active portion is a core and one end of the core is connected to a first optical device formed at the first semiconductor.

Claims

1. A method of manufacturing a semiconductor device, comprising:

providing a semiconductor substrate having a first region where a first optical device is to be formed and a second region where a waveguide is to be formed;

forming a first buried oxide layer in the semiconductor substrate in the first region so that the semiconductor substrate in the first region is divided into a lower semiconductor layer and an upper semiconductor layer, while not forming the first buried oxide layer in the semiconductor substrate in the second region;

defining an active portion by forming a trench in the semiconductor substrate in the second region;

forming a capping semiconductor pattern over a top surface of the active portion and over a sidewall of the active portion;

exposing a lower portion of the sidewall of the active portion;

oxidizing the capping semiconductor pattern and the lower portion of the sidewall of the active portion to form an oxide layer surrounding a non-oxidized portion of the active portion; and

forming a first optical device disposed in the upper semiconductor layer of the first region,

wherein the non-oxidized portion of the active portion is configured to be a core of the waveguide through which optical signals pass,

wherein the core is coupled to the first optical device, and

wherein the forming of the capping semiconductor pattern comprises;

forming a sacrificing pattern filling the trench;

exposing an upper portion of the sidewall of the active portion by recessing the sacrificing pattern;

conformally forming a capping semiconductor layer over the semiconductor substrate;

removing the capping semiconductor layer over the recessed sacrificing pattern to expose the recessed sacrificing pattern and to form the capping semiconductor pattern; and

removing the exposed sacrificing pattern to expose the lower portion of the sidewall of the active portion,

wherein the capping semiconductor pattern extends to cover a top surface of the upper semiconductor layer in the first region, and

wherein a portion of the capping semiconductor pattern over the upper semiconductor layer is oxidized by an oxidizing process, so that the oxide layer is formed over the upper semiconductor layer.

2. The method of claim 1, the method further comprising:

before forming the first optical device, removing the oxide layer over the upper semiconductor layer.

3. The method of claim 2, wherein the removing of the oxide layer over the upper semiconductor layer comprises planarizing the oxide layer until the upper semiconductor layer and a top surface of the core are exposed.