TY - JOUR

T1 - Imaging Joule heating in a conjugated-polymer light-emitting diode using a scanning thermal microscope.

AU - Boroumand, F. A.

AU - Voigt, M.

AU - Lidzey, D. G.

AU - Hammiche, Azzedine

AU - Hill, G.

PY - 2004/6/14

Y1 - 2004/6/14

N2 - We have used a scanning thermal microscope to image Joule heating in a conjugated-polymer light-emitting diode (LED). Our LEDs had an active diameter of 100 µm, which was defined using an insulating layer of silicon nitride patterned onto the LED anode. At an average power input of 0.2 mW into the LED, we find that the center of the cathode is some 0.2 K warmer than its periphery. The observed temperature distribution across the pixel is slightly asymmetric, an effect which may be correlated with spatial inhomogeneity in the local current density across the device. We present a finite element analysis thermal model which is able to accurately describe the observed temperature distribution across the LED cathode.

AB - We have used a scanning thermal microscope to image Joule heating in a conjugated-polymer light-emitting diode (LED). Our LEDs had an active diameter of 100 µm, which was defined using an insulating layer of silicon nitride patterned onto the LED anode. At an average power input of 0.2 mW into the LED, we find that the center of the cathode is some 0.2 K warmer than its periphery. The observed temperature distribution across the pixel is slightly asymmetric, an effect which may be correlated with spatial inhomogeneity in the local current density across the device. We present a finite element analysis thermal model which is able to accurately describe the observed temperature distribution across the LED cathode.

U2 - 10.1063/1.1762988

DO - 10.1063/1.1762988

M3 - Journal article

VL - 84

SP - 4890

EP - 4892

JO - Applied Physics Letters

JF - Applied Physics Letters

SN - 1077-3118

IS - 24

ER -