Improved contacts for a photovoltaic cell with two active surfaces

Patent metadata

Field	Value
Publication number	US-2019296162-A1
Application number	US-201716339838-A
Country	US
Kind code	A1
Filing date	Oct 4, 2017
Priority date	Oct 5, 2016
Publication date	Sep 26, 2019
Grant date	—

Abstract

Fabrication of a double-sided photovoltaic cell, with two opposite active surfaces, comprising a step of depositing, on each active surface, at least one electric contact. The deposition step comprises in particular a shared operation of depositing on each of the active surfaces, implemented by electrolysis in a shared electrolysis tank comprising: a first compartment for depositing a metal layer on a first active surface of the cell, for fabrication of a contact comprising said metal layer on the first active surface; and a second compartment for depositing, by oxidation, a metal oxide conductor layer on the second active surface of the cell, for the fabrication of a contact comprising said metal oxide layer on the second active surface.

First claim

1 . A method for fabrication of a double-sided photovoltaic cell, with two opposite active surfaces, comprising:
depositing, on each active surface, at least one electric contact, by electrolysis in a shared electrolysis tank; said shared electrolysis tank comprising:
a first compartment for depositing a metal layer on a first active surface of the cell, for fabrication of a contact comprising said metal layer on the first active surface; and
a second compartment for depositing, by oxidation, a metal oxide conductor layer on the second active surface of the cell, for the fabrication of a contact comprising said metal oxide layer on the second active surface.

2 . The method according to claim 1 , wherein the metal in the metal oxide layer is at least one element among Mn, Ni, Mo, Cd, Sn, In, Zn, Pb, Ag, Cu, W, Ta, Ga, Fe, Co, Cr and Ti.

3 . The method according to claim 1 , wherein, during said depositing:
electrons are generated in the first compartment, opposite the first active surface, for enhancing the deposit of the metal layer; and holes are generated in the second compartment, opposite the second active surface, for enhancing the deposit by oxidation of the metal oxide layer.

4 . The method according to claim 1 , wherein the first and second compartments are separated by an ion exchange membrane that the electrolysis tank comprises.

5 . The method according to claim 1 , wherein, the deposition:
of the metal layer on the first active surface; and of the metal oxide layer on the second active surface, is assisted by lighting of at least one of the first and second active surfaces.

6 . The method according to claim 1 , wherein the depositing operation is assisted by application of a potential difference specific for generating at least negative charges on the first active surface.

7 . The method according to claim 1 , wherein the depositing operation is assisted by application of a potential difference specific for generating positive charges on the second active surface.

8 . The method according to claim 1 , wherein the photovoltaic cell is a double-sided homojunction with n + type on the first active surface and p + on the second active surface.

9 . The method according to claim 1 , wherein the photovoltaic cell is silicon-based.

10 . The method according to claim 1 , wherein the metal layer on the first active surface is nickel-based, and the step of depositing the electric contact on the first active surface is continued by depositing a layer comprising at least copper onto the metal layer, by electrolysis.

11 . The method according to claim 1 , wherein the step of depositing the electric contact on the second active surface is continued by depositing a layer comprising at least copper onto the metal oxide layer, by electrolysis.

12 . The method according to claim 1 , wherein depositing the contact is preceded by a step of etching at least one electrically insulating layer, deposited on each active surface said etching exposes each active surface in a region in which the operation of depositing by electrolysis is applied.

13 . A double-sided photovoltaic cell with two opposite active surfaces, the cell comprising at least one electric contact on each active surface, wherein the contact for a first active surface comprises a metal layer deposited on the first active surface whereas the contact for the second active surface comprises a metal oxide conducting layer deposited on the second active surface.

14 . The cell according to claim 13 , comprising a homojunction with n + type on the first active surface and p + on the second active surface.

15 . (canceled)

Assignees

• Electricite De France
• Centre Nat Rech Scient
• Paris Sciences Lettres Quartier Latin

Inventors

• Grand Pierre-Philippe
• Lincot Daniel

Classifications

• C25D17/001

  Apparatus specially adapted for electrolytic coating of wafers, e.g. semiconductors or solar cells · CPC title

• C25D3/38

  of copper · CPC title

• Y02E10/547

  Monocrystalline silicon PV cells · CPC title

• H01L31/0684

  Electricity · mapped topic

• C25D7/12

  Semiconductors · CPC title