Study of High-Brightness LED Samples Aged Under Stress Temperature Conditions: Electrical Characterizations and Signature Evolution Analysis

Light-emitting diode (LED) components used in lighting or backlighting applications remain operational for a long time, but in some cases, early catastrophic failures and degradation of the photocolorimetric characteristics are observed. Hence, manufacturers are highly interested in early detection of degradation mechanisms and the relationship between electrical signature evolutions and aging in order to predict the remaining lifetime of LED components. This paper describes a methodology to identify future characteristics degradation based on electrical signatures observed within the first hundred hours using an accelerating aging method. For that purpose, four kinds of high-power LEDs are submitted to temperature stress conditions that provide early aging electrical signatures. The first part of this paper describes the experimental setup and the aging protocol. In the second part, we present signatures obtained via current-voltage (I-V ) and capacitance-voltage (C-V ) data.