Currently GaN based blue light emission diode(LED) has already been widely used in spotlight of cars

back light of mobile phones

outdoor displays

etc.As the market of its applications is rapidly enlarged

the reliability of GaN based LED becomes the top issure of wide concern.In order to improve the reliability of vertical GaN based blue LED on Si substrate

SiN passivation layer was deposited by PECVD on the chip of LED

stresses in different condition were carried out to both passivated and unpassivated chips and encapsulated LEDs

their optical and electrical properties were investigated.After the aging under the condition of 30 mA

85℃ for 24 hours

the average luminous decay for encapsulated LEDs without SiN layer was 11.41%

but 6.06% for passivated one

lower luminous decay of SiN passivated GaN based blue LED was also found at the aging condition of RT

30 mA

96 hours

this was never reported in previous dissertations.In the aging experiment of chips under the 500 mA

RT condition

higher reverse voltage of SiN passivated LED was found after aging compared with that without SiN layer

but no obvious improvement for ESD property.