Patent ID: 8743921
Filing Date: 2014-06-03
Classification: H01L

Abstract:
1. A light emitting module comprising: a semiconductor light emitting device having a junction, and a thermal switch device having two terminals and two states: a conducting state that effectively creates a short circuit between the two terminals and a non-conducting state that effectively creates an open circuit between the two terminals, wherein: the thermal switch device is arranged in parallel with, and in thermal contact with, the light emitting device and is configured to enter the conducting state at and above a predetermined shunt temperature, protecting the junction from reaching a critical, higher temperature under operating conditions, and the thermal switch device comprises a HCTE (High Coefficient of Thermal Expansion) material with a coefficient of thermal expansion αh and a LCTE (Low Coefficient of Thermal Expansion) material with a coefficient of thermal expansion αl, and αh>αl.