Ordering-induced band structure effects in GaInP2 studied by ballistic electron emission microscopy

We have analyzed the second voltage derivative (SD) of the ballistic electron emission microscopy (BEEM) spectra of ${\mathrm{GaInP}}_{\mathrm{2}}.$ We associate two peaks observed in the SD-BEEM spectra of disordered ${\mathrm{GaInP}}_{\mathrm{2}}$ on $n^{+}$ GaAs substrate with the Γ and L conduction minima, $\text{Δ(Γ−L)∼0.35\hspace{0.05em}}\mathrm{eV}.$ An additional third peak appearing in the SD-BEEM spectrum of ordered ${\mathrm{GaInP}}_{\mathrm{2}}\text{\hspace{0.05em}(η∼0.5)}$ is associated with the L-band splitting due to the ordering-induced “folding” of one of the four L valleys onto the $\mathrm{\Gamma ̄}$ point. According to our results, this splitting is ∼ 0.13 eV.