Implantation of rare-earth ion into ZnS and ZnSe has been used for fabrication of LEDs with MS structure.The implantation processes were carried out by using an ion beam energy of 20keV and with the substrate at 77K.In the present experiments

erbium ions were implanted into ZnSe with the substrate at 300K.After annealing the ZnSe:Er

3+

crystal in N

2

atmosphere

ZnSe:Er

3+

LED with MIS structure was fabricated.According to the reason of I layer forming

we first proposed that the I layer could be eliminated by annealing Er

3+

-implanted ZnSe crystals in melten zinc and the LED with MS structure could be fabricated.ZnSe crystals were grown from the vapour phase in sealed capsules con-tainting slight excess of zinc in our laboratory.Dice with dimensions of 6×6×1mm

3

were annealed in melten zinc to reduce their resistivities to the range of 1-10Ω·cm.Erbium ions with energy of 100keV and dose of 1×10

15

cm

-2

were implanted into ZnSe substrate at room temperature.Annealing was performed in N

2

atmosphere or in melten zinc

respectively.