The electronic and magnetic properties of Mn doping at either cation sites in the class of I–III–${\mathrm{VI}}_2$ chalcopyrites are studied by first-principles calculation. It is found that Mn doping at the III site provides holes and stabilizes the ferromagnetic interaction between neutral Mn defects; the neutral ${\mathrm{Mn}}_{\mathrm{Cu}}^0$ also stabilizes the ferromagnetism, although it provides electrons to the conduction band, instead of holes. The ferromagnetic stability is generally weaker when the cation or the anion becomes heavier in these chalcopyrites, i.e., along the sequences ${\mathrm{CuAlS}}_2\to {\mathrm{CuGaS}}_2\to {\mathrm{CuInS}}_2$ and ${\mathrm{CuGaS}}_2\to {\mathrm{CuGaSe}}_2\to {\mathrm{CuGaTe}}_2.$ Interestingly, ${\mathrm{CuAlO}}_2$ in the chalcopyrite structure is predicted to have lower FM energy than ${\mathrm{CuAlS}}_2$ despite its lighter anion and shorter bonds. In general, III site substitution gives stabler ferromagnetism than Cu substitution. Thus, the preferred growth conditions are Cu-rich and III-poor, which maximize ${\mathrm{Mn}}_{\mathrm{III}}$ replacement. In n-type samples, when ${\mathrm{Mn}}_{\mathrm{III}}$ is negatively charged, the antiferromagnetic coupling is preferred. In p-type samples, the ground state of positively charged ${\mathrm{Mn}}_{\mathrm{Cu}}^{+}$ is also antiferromagnetism. The main feature of the calculated electronic properties of Mn defect at either Cu or III site is explained using a simple picture of dangling bond hybride and crystal-field resonance.

• Received 16 October 2003

DOI:https://doi.org/10.1103/PhysRevB.69.104422