Methods and Systems for Characterizing Photovoltaic Cell and Module Performance at Various Stages in the Manufacturing Process

摘要

A method of quantum efficiency (QE) photovoltaic measurement is provided that includes coupling measurement electronics to a p-n junction of a Cell Under Test (CUT) that are capable of measuring a pulsed DC photocurrent. The measurement electronics output a response by the CUT to turning on and turning off the pulsed DC photocurrent that are digitized and analyzed for the magnitude that is representative of a conversion efficiency of the CUT to a wavelength of the DC photocurrent, where a measured decay time represents the p-n junction or the minority carrier lifetime. The CUT is exposed to the pulsed DC photocurrent, where signatures of the response to turning off and on to the pulsed DC photocurrent overlap, where a combined amplitude of the response is proportional to an efficiency of a production of photocarriers, where a value of a spectral response at a wavelength is determined.

主权项

1. A sequential method of quantum efficiency (QE) photovoltaic measurement, comprising:
a. using a plurality of DC or pulsed light sources directed at the p-n junction of a Cell Under Test (CUT), wherein each said DC or pulsed light source emits a controlled pulse of quasi-monochromatic light, wherein the output of each said DC or pulsed light source comprises a unique wavelength, wherein the response of the CUT is detected by coupling measurement electronics that are capable of measuring a DC or pulsed DC photocurrent from said CUT, wherein said measurement electronics output a response by said CUT to turning on said pulsed or DC light sources and a response by said CUT to turning off said pulsed or DC light sources, wherein said response by said CUT to turning on said pulsed or DC light sources is digitized and analyzed and said response by said CUT to turning off said pulsed or DC light sources is digitized and analyzed, wherein the magnitude of said CUT response is representative of a conversion efficiency of said CUT to a wavelength of said pulsed or DC light source, wherein a measured decay time of said CUT response is analyzed using an appropriately programmed computer to extract a decay time or leakage current of said p-n junction; and b. exposing said CUT to said pulsed or DC light source, using an illumination source comprised of a plurality of DC or pulsed quasi-monochromatic light sources, wherein signatures of said response by said CUT to turning on each said pulsed or DC light source and said response by said CUT to turning off each said pulsed or DC light source overlap, wherein a combined amplitude of said response by said CUT to turning on said pulsed or DC light source and said response by said CUT to turning off said pulsed or DC light source is proportional to an efficiency of a production of photocarriers in said CUT, wherein a value of a spectral response or Quantum Efficiency (QE) of the CUT at a wavelength of said illumination source is determined.