The Phase Identification of  H 2 SO 4 ‐ Etched InP by X‐Ray Diffraction

Abstract

The chemical composition of surface oxides grown on p-type InP(100) after etching in H 2 SO 4 /H 2 O and in H 2 SO 4 /H 2 O 2 /H 2 O etchants was investigated using X-ray wide angle diffraction and glancing angle diffraction techniques. Diffraction from only one lattice set in the matrix oxide was detected in etching with H 2 SO 4 /H 2 O solution by wide angle diffraction. Each diffraction line appeared as an interference pattern, possibly caused by beams reflected from thin layers of indium phosphate hydrate having a single-crystal structure, and showing an extremely preferred orientation and coherent with respect to the substrate. Only one set of reflection peaks was observed in wide angle diffraction, and an interference oscillation was observed in each reflected beam. The dissolution rates of InP in H 2 SO 4 /H 2 O and in H 2 SO 4 /H 2 O 2 /H 2 O were determined quantitatively by inductively coupled plasma emission spectrometry. The mixed component oxides and single component products were observed on the oxidized InP. The dissolution rates of InP were almost indiscernible under either illumination or dark. The addition of H 2 O 2 in H 2 SO 4 /H 2 O solution does not play any critical role in the dissolution of InP.

Shape Control in Epitaxial Electrodeposition: Cu2O Nanocubes on InP(001)

“…The InP surface is known to be ordered after H 2 SO 4 etching. Yao and Itaya have observed an ordered surface by in situ STM that is consistent with ideal (1 × 1) termination of the bulk structure, while Liu et al have determined by X-ray diffraction that the surface may be crystalline InPO 4 · x H 2 O after H 2 SO 4 etching . The amorphous layer in our study may have resulted from a postdeposition reaction between Cu 2 O and either InP or InPO 4 · x H 2 O.…”

Inverse Metal-Assisted Chemical Etching Produces Smooth High Aspect Ratio InP Nanostructures

“…For example, anodic oxides mainly consist of In 2 O 3 and P 2 O 5 , while mixture combination of In 2 O 3 and InPO 4 are formed in thermal oxides. 44 In order to further determine whether or not the thicker oxide layer formed at the Au/InP interface during I-MacEtch differs in composition from the thin native oxide present elsewhere, Xray photoelectron spectroscopy (XPS) experiments were carried out. Figure 7a,b shows normalized high-resolution photoelectron core-level spectra in the regions of the P 2p and In 3d bonding states, respectively, obtained from InP surfaces that were Au-patterned (thicker oxide, red curves) and nonpatterned (exposed InP surface with native oxide, black curves) during I-MacEtch.…”

“…It is known that different oxidation approaches produce different kinds of oxides for InP. For example, anodic oxides mainly consist of In 2 O 3 and P 2 O 5 , while mixture combination of In 2 O 3 and InPO 4 are formed in thermal oxides . In order to further determine whether or not the thicker oxide layer formed at the Au/InP interface during I-MacEtch differs in composition from the thin native oxide present elsewhere, X-ray photoelectron spectroscopy (XPS) experiments were carried out.…”

Epitaxial Electrodeposition of High-Aspect-Ratio Cu2O(110) Nanostructures on InP(111)

“…This agrees with the results of a recent study on the Cu 2 O/InP(100) system, where we have identified the amorphous layer to be InPO 4 . In fact, InP is known to form crystalline indium phosphate hydrate (InPO 4 · x H 2 O) after H 2 SO 4 etching D, on the other hand, indicates a Cu:O ratio close to 1:1 in this region.…”