Efficient AlGaN-Based Deep-Ultraviolet LED With N-Side Located Tunnel Junction

In this work, we investigated a 279 nm AlGaN-based DUV LED incorporating a n-side located tunnel junction (namely n-side-TJ LED). Compared with the conventional AlGaN-based DUV LED with p-side located tunnel junction (namely p-side-TJ LED), the light output power (LOP) of the n-side-TJ LED can be boosted by 19.4% at an injection current density of 667 A/cm2. This is attributed to the improvement of the effective barrier height in the electron blocking layer (EBL) for efficient electron blocking. In addition, we further studied the effect of the thickness of n-side located tunnel junction (n-side-TJ) layers on the performance of the LED. The n-side-TJ LED can maintain a superior and stable performance when the TJ thickness is altered. On the contrary, the p-side-TJ LED exhibits performance fluctuations as the TJ thickness changes. These results highlight the effectiveness of structural design with a tunnel junction for highly efficient AlGaN-based DUV LEDs.