The temperature distribution in InGaN-MQW light emitting diodes was examine
d during operation with spatially resolved micro-Raman and micro-Electrolum
inescence measurements. The experimental results were compared to finite el
ement simulations. A good agreement between the different experimental and
calculated data is found. Maximum operation temperatures up to 140 degreesC
at a moderate forward currents of 30 mA are revealed by all three independ
ent methods. Influences of substrate thickness, different substrates, and e
ven bond-wires are shown.