Variablehyphen;fluence 3hyphen;MeV Si+and 150hyphen;keV Ge+implants were performed into InP:Fe at 200thinsp;deg;C. Lattice damage in the material is greatly reduced over comparable roomhyphen;temperature (RT) implantations and is rather insensitive to fluence for Si+implantation in the range of 8 times; 1014ndash;5 times; 1015cmminus;2, and no amorphization occurs. For 8 times; 1014hyphen;cmminus;2Si+implantation at 200thinsp;deg;C, the dopant activation is 82percnt; and carrier mobility is 1200 cm2/Vthinsp;s after 875thinsp;deg;C/10hyphen;s annealing, whereas for the RT implantation the corresponding values are 48percnt; and 765 cm2/Vthinsp;s, respectively. The reasons for the improved mobility in the elevatedhyphen;temperature implants were investigated using Rutherfordhyphen;backscattering spectrometry. At a dose of 8 times; 1014cmminus;2, the aligned yield after annealing is close to that of a virgin sample, indicating a low concentration of residual damage in the 200thinsp;deg;C implant, whereas the lattice remained highly defective in the RT implanted sample. Elevatedhyphen;temperature implantation of Si+and Pi+ions was also investigated. Coimplantation did yield an improvement in activation for an implanted fluence of 2 times; 1015cmminus;2Si+, but resulted in an inferior lattice quality which degraded the carrier mobility compared to a Si+(only) implant. For a 1 times; 1014hyphen;cmminus;2Ge+implant, the maximum dopant activation is 50percnt; (donor) and the material did not turnptype even after 925thinsp;deg;C annealing.
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