Energy conversion device and method of forming the same

Patent metadata

Field	Value
Publication number	US-2018159162-A1
Application number	US-201615575614-A
Country	US
Kind code	A1
Filing date	May 20, 2016
Priority date	May 22, 2015
Publication date	Jun 7, 2018
Grant date	—

Abstract

Various embodiments may provide a method of forming an energy conversion device. The method may include forming an electrolyte layer on the first surface of the semiconductor substrate. The method may also include forming a cavity on the second surface of the semiconductor substrate using a deep reactive ion etch. The method may further include enlarging said cavity by carrying out one or more wet etches so that the enlarged cavity is at least partially defined by a vertical arrangement comprising a first lateral cavity surface of the semiconductor substrate extending substantially along a first direction, and a second lateral cavity surface of the semiconductor substrate adjoining the first lateral cavity surface. The method may include forming a first electrode on a first surface of the electrolyte layer, and forming a second electrode on a second surface of the electrolyte layer.

First claim

1 . A method of forming an energy conversion device, the method comprising:
forming an electrolyte layer on a first surface of a semiconductor substrate that also includes a second surface opposite the first surface; forming a cavity at the second surface of the semiconductor substrate using a deep reactive ion etch; enlarging said cavity by carrying out one or more wet etches so that the enlarged cavity is at least partially defined by a vertical arrangement comprising a first lateral cavity surface of the semiconductor substrate extending substantially along a first direction, and a second lateral cavity surface of the semiconductor substrate adjoining the first lateral cavity surface, the second lateral cavity extending substantially along a second direction different from the first direction; forming a first electrode on a first surface of the electrolyte layer; and forming a second electrode on a second surface of the electrolyte layer.

2 . The method according to claim 1 , wherein the second lateral cavity surface extends at an angle selected from a range of about 3° to about 4° from the first surface of the semiconductor substrate.

3 . The method according to claim 1 ,
wherein the second lateral cavity surface is a shoulder region extending substantially parallel to the first surface of the semiconductor substrate; and wherein the enlarged cavity is further defined by a third lateral cavity surface adjoining the second lateral cavity surface so that the second lateral cavity surface is between the first lateral cavity surface and the third lateral cavity surface.

4 . The method according to claim 1 , further comprising:
forming a plurality of trenches on the first surface of the semiconductor substrate before forming the electrolyte layer.

5 . The method according to claim 1 , further comprising:
forming a first dielectric layer on the first surface of the semiconductor substrate and a second dielectric layer on the second surface of the semiconductor substrate before forming the electrolyte layer.

6 . The method according to claim 5 , further comprising:
removing a portion of the second dielectric layer so that a portion of the second surface of the semiconductor substrate is exposed for forming the cavity.

7 . The method according to claim 6 , wherein the portion of the second dielectric layer is removed using reactive ion etching.

8 . The method according to claim 1 , wherein the one or more wet etches comprises a first wet etch carried out at a first temperature and a second wet etch carried out at a second temperature lower than the first temperature.

9 . The method according to claim 1 , wherein the one or more wet etches is carried out until the electrolyte layer is exposed.

10 . The method according to claim 1 , wherein the first lateral cavity surface is substantially along the (111) plane of the semiconductor substrate.

11 . The method according to claim 1 , wherein the first lateral cavity surface forms a rounded junction with the second lateral cavity surface.

12 . The method according to claim 1 , wherein the enlarged cavity is at least partially defined by the electrolyte layer and forms a circular interface with the electrolyte layer.

13 . The method according to claim 1 , wherein the semiconductor substrate is a silicon substrate.

14 . An energy conversion device formed by a method comprising:
forming an electrolyte layer on a first surface of a semiconductor substrate that also includes a second surface opposite the first surface; forming a cavity at the second surface of the semiconductor substrate using a deep reactive ion etch; enlarging said cavity by carrying out one or more wet etches so that the enlarged cavity is at least partially defined by a vertical arrangement comprising a first lateral cavity surface of the semiconductor substrate extending substantially along a first direction, and a second lateral cavity surface of the semiconductor substrate adjoining the first lateral cavity surface, the second lateral cavity extending substantially along a second direction different from the first direction; forming a first electrode on a first surface of the electrolyte layer; and forming a second electrode on a second surface of the electrolyte layer.

15 . An energy conversion device comprising:
a semiconductor substrate having a first surface and a second surface opposite the first surface, the semiconductor substrate comprising an enlarged cavity at the second surface, wherein the enlarged cavity is at least partially defined by a vertical arrangement comprising a first lateral cavity surface extending substantially along a first direction, and a second lateral cavity surface adjoining the first lateral cavity surface, the second lateral cavity surface extending substantially along a second direction different from the first direction; an electrolyte layer on the first surface of the semiconductor substrate; a first electrode on a first surface of the electrolyte layer; and a second electrode on a second surface of the electrolyte layer.

16 . The energy conversion device according to claim 15 , wherein the electrolyte layer is suspended over the enlarged cavity.

17 . The energy conversion device according to claim 15 , wherein the electrolyte layer is corrugated.

18 . The energy conversion device according claim 15 , where the second electrode extends from on the second surface of the electrolyte layer over the first lateral cavity surface and the second lateral cavity surface to on the second surface of the semiconductor substrate.

19 . The energy conversion device according to claim 15 , wherein the electrolyte layer comprises a solid state oxygen ion-conductor or a proton conductor.

20 . The energy conversion device according to claim 15 , wherein the electrolyte layer comprises yttria-stabilized zirconia (YSZ) or yttrium-doped BaZrO 3 (BYZ).

21 . The energy conversion device according to claim 15 , wherein the energy conversion device is a solid oxide fuel cell or a solid oxide fuel cell array.

Assignees

• Univ Nanyang Tech

Inventors

• Su Pei-Chen
• Yoon Yong Jin
• Baek Jong Dae

Classifications

• H01M8/1253 Primary

  the electrolyte containing zirconium oxide · CPC title

• H01M2008/1293

  Fuel cells with solid oxide electrolytes · CPC title

• H01M8/006

  Flat · CPC title

• C09K13/02

  containing an alkali metal hydroxide · CPC title

• H01M8/2432

  Grouping of unit cells of planar configuration · CPC title