For modern high-power LEDs, self-heating becomes a critical factor determining their functional characteristics and lifetime. For large-area LEDs with a complex structure, it is important to know not only the thermal resistance but also the detailed temperature distribution (temperature map) over the active area. We report a technique which can simplify and improve the Infrared (IR) micro-thermography of light-emitting diodes (LEDs) by the use of a special thin-film coating which combines strong absorption in the wavelength range of sensitivity of IR microscope (2.5–3 μm) and transparency in the visible region of the own LED radiation. As known, conventional IR temperature measurements, made on the LEDs, lead to significant difficulties and errors as a consequence of the optical transparency of substrate/heterostructure layers and a low emissivity of metallised contacts. The proposed method allows avoiding the time-consuming procedure of emissivity calibration for different materials forming LEDs while increasing the measurement accuracy.

对于现代大功率LED，自热成为决定其功能特性和寿命的关键因素。对于结构复杂的大面积LED，重要的是，不仅要了解热阻，而且还要了解有效区域上的详细温度分布（温度图）。我们报告了一种技术，该技术可以通过使用特殊的薄膜涂层来简化和改善发光二极管（LED）的红外（IR）显微热成像技术，该涂层结合了IR显微镜灵敏度范围内的强吸收性（2.5 –3μm）和自身LED辐射的可见光区域的透明度。众所周知，在LED上进行常规IR温度测量时，由于衬底/异质结构层的光学透明性以及金属化触点的低发射率，导致严重的困难和错误。所提出的方法可以避免形成LED的不同材料的发射率校准的耗时过程，同时提高了测量精度。