Semiconductor device production process

• US 8,664,028 B2
• Filed: 03/09/2012
• Issued: 03/04/2014
• Est. Priority Date: 03/11/2011
• Status: Expired due to Fees

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: Shibata, Yasuyuki, Liang, Ji-Hao
• Primary Examiner(s): WILCZEWSKI, MARY A
• Application Number:
  US13/416,344
• Publication Number:
  US 20120231568A1
• Time in Patent Office: 725 Days
• Field of Search: 438/46, 438/456, 438/458, 438/493, 438/977, 257/E21.097, 257/E33.006, 257/E33.025
• US Class Current: 438/46
• CPC Class Codes: H01L 21/0242 Crystalline insulating materials
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/02513 Microstructure
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/02576 N-type
• CPC Class Codes: H01L 21/0259 Microstructure
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/02639 Preparation of substrate for selective deposition
• CPC Class Codes: H01L 21/0265 Pendeoepitaxy
• CPC Class Codes: H01L 21/02664 Aftertreatments planarisation in general H01L21/304
• CPC Class Codes: H01L 21/187 by direct bonding
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate

Abstract

(a) On a growth substrate, a void-containing layer that is made of a group III nitride compound semiconductor and contains voids is formed. (b) On the void-containing layer, an n-type layer that is made of an n-type group III nitride compound semiconductor and serves to close the voids is formed. (c) On the n-type layer, an active layer made of a group III nitride compound semiconductor is formed. (d) On the active layer, a p-type layer made of a p-type group III nitride compound semiconductor is formed. (e) A support substrate is bonded above the p-type layer. (f) The growth substrate is peeled off at the boundary where the voids are produced. In the above step (a) or (b), the supply of at least part of the materials that form the layer is decreased, while heating, before the voids are closed.

Claims

1. A semiconductor device production process comprising:

(a) forming on a growth substrate a void-containing layer that is made of a group III nitride compound semiconductor and contains voids,

(b) forming on the void-containing layer an n-type layer that is made of an n-type group III nitride compound semiconductor and serves to close the voids,

(c) forming on the n-type layer an active layer made of a group III nitride compound semiconductor,

(d) forming on the active layer a p-type layer made of a p-type group III nitride compound semiconductor,

(e) bonding a support substrate above the p-type layer, and

(f) peeling off the growth substrate at a position in an area where the voids are produced;

wherein said (a) forming the void-containing layer comprises a first growth step in which the group III nitride compound semiconductor grows under conditions such that vertical growth is mainly promoted, a second growth step in which the group III nitride compound semiconductor grows under conditions such that horizontal growth is mainly promoted, and a repeating step in which steps that are the same as the first growth step and the second growth step, respectively, are alternately repeated; and

wherein said (a) forming the void-containing layer or said (b) forming the n-type layer comprises a desorption acceleration step in which a supply rate of a group III material is decreased to less than that in the first growth step and the second growth step, under conditions where the desorption of the group III nitride compound semiconductor proceeds more actively than the growth of the layer, while heating, before the voids are closed.

2. A semiconductor device production process as claimed in claim 1,

wherein the group III nitride compound semiconductor that forms the void-containing layer and the n-type layer is GaN,

wherein in said (a) forming the void-containing layer and said (b) forming the n-type layer, TMG and NH₃ are supplied to form the void-containing layer and the n-type layer, and

wherein in the desorption acceleration step, only a supply rate of TMG is decreased, and a supply rate of NH₃ and an ambient temperature are maintained.

3. A semiconductor device production process as claimed in claim 2, wherein in the desorption acceleration step, the supply rate of TMG is decreased to 10 μ

mol/min or less.

4. A semiconductor device production process as claimed in claim 2, wherein in the desorption acceleration step, the supply rate of TMG is decreased to 0 μ

mol/min.

5. A semiconductor device production process as claimed in claim 1, wherein the desorption acceleration step starts at a time when an opening ratio of the voids reaches a value in a range of 5% or more and 40% or less.

6. A semiconductor device production process as claimed in claim 1, wherein the desorption acceleration step is performed for a duration of 1 minute or more and 10 minutes or less.

7. A semiconductor device production process as claimed in claim 1, wherein the desorption acceleration step is performed in said (b) forming the n-type layer.