Methods of hyperdoping semiconductor materials and hyperdoped semiconductor materials and devices
Methods are disclosed for producing highly doped semiconductor materials. Using the invention, one can achieve doping densities that exceed traditional, established carrier saturation limits without deleterious side effects. Additionally, highly doped semiconductor materials are disclosed, as well as improved electronic and optoelectronic devices/components using said materials. The innovative materials and processes enabled by the invention yield significant performance improvements and/or cost reductions for a wide variety of semiconductor-based microelectronic and optoelectronic devices/systems. Materials are grown in an anion-rich environment, which, in the preferred embodiment, are produced by moderate substrate temperatures during growth in an oxygen-poor environment. The materials exhibit fewer non-radiative recombination centers at higher doping concentrations than prior art materials, and the highly doped state of matter can exhibit a minority carrier lifetime dominated by radiative recombination at higher doping levels and higher majority carrier concentrations than achieved in prior art materials. Important applications enabled by these novel materials include high performance electronic or optoelectronic devices, which can be smaller and faster, yet still capture or emit light efficiently, and high performance electronics, such as transistors, which can be smaller and faster, yet cooler.
1. A method for producing a hyperdoped semiconductor material using an epitaxial growth process, comprising operating a growth chamber at a substrate temperature of 300 to 500° C. while providing at least one anion, at least one cation and a selected dopant, and while maintaining a partial pressure for oxygen atoms, radicals, molecules and oxygen-containing or bearing compounds and materials of less than 10 −9 torr.
2. A method for producing a hyperdoped compound semiconductor material, comprising introducing dopant atoms into a compound semiconductor material at a concentration greater than the bulk carrier saturation limit of the dopant in the semiconductor material, said semiconductor material comprised of at least one cation element and at least one anion element such that in the resulting hyperdoped semiconductor material there is an excess of anion atoms, substantially all of the dopant atoms are located on cation substitutional sites, and minority carrier recombination is dominated by radiative recombination.
3. A method as in claim 2 , wherein the step of introducing comprises operating a growth chamber at a moderate substrate temperature while providing the anion atoms, cation atoms and the dopant atoms, and while maintaining a low background pressure for oxygen atoms, radicals, molecules and oxygen-containing or bearing compounds.
4. A method as in claim 2 , wherein the step of introducing comprises implanting into the compound semiconductor material the dopant atoms, and further comprising performing a thermal anneal.