Optical Properties of Implanted GaN

Ion implantation is widely used in semiconductor device technology to locally alter the electrical properties of materials. Since only the electrical properties are generally of interest, the optical properties of implanted semiconductors are not often reported in detail, despite the excellent sensitivity of optical investigation to the removal of damage by post-implantation thermal annealing. Optical measurements could be useful to GaN researchers seeking an optimal post-implant annealing procedure. 

FIGURE 1 PL spectra of various elements implanted in GaN and activated by 1050°C anneal in flowing NH3 (after [3]). 

FIGURE 2 compares the room temperature PL data from Zn-implanted GaN samples annealed at 1150°C and 1250°C under 10 kbar N2 with an MOVPE-doped GaN Zn reference sample and the undoped GaN/sapphire starting material [8], The MOVPE Zn dopant concentration was designed to closely match the implantation profile to provide an accurate comparison of the relative Zn luminescence efficiencies. The spectra observed in all of the Zn-doped samples are similar, differing rally in intensity, which confirms the activation of the implanted Zn acceptors. The sample annealed at 1250°C shows intense Zn PL roughly an order of magnitude stronger than in the epitaxial GaN Zn reference sample 

The 1150°C annealed sample PL is comparable to the reference except that its exciton luminescence has not recovered, which suggests that implant damage has not been fully removed by annealing. 

FIGURE 2 Room temperature PL data. The Zn-implanted GaN annealed at 1250°C under 10 kbar of N2 luminesces roughly an order of magnitude more efficiently than the epitaxially doped GaN Zn reference sample (after [8]). 

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B3.2 Impurity redistribution of implanted and annealed GaN B3.3 Electrical properties of ion implanted and annealed GaN B3.4 Optical properties of implanted GaN... 

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