Solar cell element and method for manufacturing solar cell element

Patent metadata

Field	Value
Publication number	US-10749047-B2
Application number	US-201916365527-A
Country	US
Kind code	B2
Filing date	Mar 26, 2019
Priority date	Sep 29, 2016
Publication date	Aug 18, 2020
Grant date	Aug 18, 2020

Abstract

The solar cell element includes a semiconductor substrate with first and second surfaces, a passivation layer located on the second surface, a protective layer located on the passivation layer, and a back-surface electrode located on the protective layer. The back-surface electrode is electrically connected to the semiconductor substrate via one or more hole portions penetrating the protective layer and the passivation layer. The protective layer includes a first region showing a tendency to increase in thickness as a distance from an inner edge portion of the hole portion and a second region surrounding the first region. A distance between a position of the first region farthest from the inner edge portion and the inner edge portion is larger than a thickness in the second region. The back-surface electrode shows a tendency to decrease in thickness on the first region as a distance from the inner edge portion.

First claim

The invention claimed is:

1. A solar cell element comprising:
a semiconductor substrate having a first surface and a second surface opposite the first surface;
a passivation layer located on the second surface;
a protective layer located on the passivation layer; and
a back-surface electrode located on the protective layer,
wherein
the back-surface electrode is electrically connected to the semiconductor substrate via one or more hole portions penetrating the protective layer and the passivation layer,
the protective layer includes a first region that increases in thickness as a distance from an inner edge portion of the hole portion increases toward a second region surrounding the first region,
a distance between a position of the first region farthest from the inner edge portion and the inner edge portion is larger than a thickness in the second region, and
the back-surface electrode decreases in thickness as a distance from the inner edge portion increases in a region of the back-surface electrode on the first region.

2. The solar cell element according to claim 1 , wherein the inner edge portion includes a concavo-convex portion in perspective plan view of the protective layer.

3. The solar cell element according to claim 1 , wherein
the one or more hole portions include a first hole portion and a second hole portion adjacent to each other, and
a distance between a position of the first region farthest from the inner edge portion and the inner edge portion located around the first hole portion is less than half of a distance between the first hole portion and the second hole portion.

4. The solar cell element according to claim 1 , wherein
the passivation layer includes a first passivation layer present in a position in contact with the semiconductor substrate and a second passivation layer present in a position in contact with the protective layer, and
the second passivation layer and the protective layer contain a same main component.

5. The solar cell element according to claim 1 , wherein the protective layer contains chlorine.

6. The solar cell element according to claim 5 , wherein a portion located on a back-surface electrode side of the protective layer is higher in chlorine concentration than a portion located on a passivation layer side of the protective layer.

7. The solar cell element according to claim 5 , wherein the passivation layer contains chlorine.

Assignees

• Kyocera Corp

Inventors

• Matsushima Norihiko
• Mizumoto Akihiro
• Murao Akira
• Aranami Junji

Classifications

• H10F77/703

  of the semiconductor bodies, e.g. textured active layers · CPC title

• H10F77/219

  Arrangements for electrodes of back-contact photovoltaic cells · CPC title

• H10F10/14

  Photovoltaic cells having only PN homojunction potential barriers · CPC title

• H10F77/311 Primary

  for photovoltaic cells · CPC title

• Y02E10/547

  Monocrystalline silicon PV cells · CPC title