Development of silicon wafer packaging technology for deep UV LED

Abstract

This paper reports a deep‐ultraviolet LED (deep‐UV‐LED) package based on silicon MEMS process technology (Si‐PKG). The package consists of a cavity formed by silicon crystalline anisotropic etching, through‐silicon vias (TSVs) filled with electroplated Cu, bonding metals made of electroplated Ni/AuSn and a quartz lid for hermetic sealing. A deep‐UV LED die is directly mounted in the Si‐PKG by AuSn eutectic bonding without a submount. It has advantages in terms of size, heat dissipation, light utilization efficiency, productivity and cost over conventional AlN ceramic packages. We confirmed a light output of 30 mW and effective reflection on Si (111) cavity slopes in the Si‐PKG. Based on simulation, further improvement of the optical output is expected by optimizing DUV‐LED die mount condition.

Recent Advances in Packaging Technologies of AlGaN‐Based Deep Ultraviolet Light‐Emitting Diodes

“…However, aluminum shows a very high reflectivity (>90%) in deep UV region which is suitable for making the deep UV sub-mounts. [105,[113][114][115] Kuo et al of National Chiao Tung University proposed an aluminum-based sidewall reflector to enhance the LEE of AlGaN-based deep UV LED, as a result the output power increases by 18.38%. [116] The hollow packaging structure is also called inorganic packaging structure due to avoiding the high energy UV light emitting to the organic adhesive directly.…”

“…However, aluminum shows a very high reflectivity (>90%) in deep UV region which is suitable for making the deep UV sub‐mounts. [ 105,113–115 ] Kuo et al. of National Chiao Tung University proposed an aluminum‐based sidewall reflector to enhance the LEE of AlGaN‐based deep UV LED, as a result the output power increases by 18.38%.…”