US 10,892,376 B2 · Method and device for producing a photovoltaic element with stabilised efficiency

Abstract

According to an example, in a method for producing a photovoltaic element with stabilised efficiency, a silicon substrate may be provided with an emitter layer and electrical contacts, which may be subjected to a stabilisation treatment step. Hydrogen from a hydrogenated silicon nitride layer may be introduced into the silicon substrate, for example, within a zone of maximum temperature. The silicon substrate may then be cooled rapidly in a zone in order to avoid hydrogen effusion. The silicon substrate may then be maintained, for example in a zone within a temperature range of from 230° C. to 450° C. for a period of, for example, at least 10 seconds. The previously introduced hydrogen may thereby assume an advantageous bond state. At the same time or subsequently, a regeneration may be carried out by generating excess minority charge carriers in the substrate at a temperature of at least 90° C., preferably at least 230° C.

Claims13

Dependent claims

A method for producing a photovoltaic element with stabilised efficiency, comprising the following steps:

providing a silicon substrate;
forming an emitter layer at a surface of the silicon substrate;
forming electrical contacts on the silicon substrate;
wherein the method further comprises a stabilising treatment step comprising:
introducing hydrogen into the silicon substrate from a hydrogen-containing dielectric layer applied onto the silicon substrate, wherein the hydrogen is introduced at temperatures of the substrate above 650° C. and subsequent cooling the substrate to 450° C. is carried out with a ramp at a cooling rate of at least 10° C./s, preferably at least 20° C./s, more preferably at least 30° C./s, yet more preferably at least 60° C./s, while the substrate is at a temperature above 550° C. during the cooling of the substrate;
and
generating excess minority charge carriers in the silicon substrate while the silicon substrate is at a temperature above 230° C., wherein the excess minority charge carriers are generated by illumination with an illumination intensity greater than 1 kW/m2 with light having wavelengths less than 1180 nm.

4 more elements

A method for treating a silicon substrate within the context of the production of a photovoltaic element in a device being in the form of a continuous furnace having a plurality of zones including a maximal heating zone, a cooling zone and a temperature maintenance zone, wherein the plurality of zones is adjustable to different temperatures and comprises an illumination device, wherein the device comprises in each of its maximal zone and temperature maintenance zone at least one radiant heater for heating the silicon substrate to an elevated temperature and wherein the device comprises in its cooling zone no radiant heater but a cooling device for actively cooling passing silicon substrates, the method comprising:

heating a silicon substrate passing through the continuous furnace for a time at a temperature above 650° C. in the maximal heating zone;
following the heating, cooling the silicon substrate to a temperature below 450° C. in the cooling zone at a cooling rate of at least 10° C./s, while the substrate is at a temperature above 550° C. during the cooling of the silicon substrate;
and
following the cooling,
maintaining the silicon substrate at a temperature of between 230° C. and 450° C. in the temperature maintenance zone;
and
at the same time or subsequently as the maintaining, illuminating the silicon substrate at a temperature of at least 230° C. with an illumination intensity greater than 1 kW/m2 with light having wavelengths less than 1180 nm.

4 more elements

Dependencies are inferred from the claim text.

Method and device for producing a photovoltaic element with stabilised efficiency

Life of this patent

Method and device for producing a photovoltaic element with stabilised efficiency

Life of this patent

Abstract

Claims13