In this work, multiple sets of CdZnTe/CdTe strained-layer superlattices have been used as dislocation filtering layers for reducing the threading dislocations and improving the material quality of CdTe buffer layers grown by molecular beam epitaxy (MBE) on GaSb (211)B substrates. By incorporating a CdZnTe/CdTe superlattice filtering structure, a significant improvement in material quality has been achieved, with a low etch pit density of ∼ 1 × 10⁵ cm⁻² demonstrated for CdTe grown on GaSb, which is two orders of magnitude lower than previously reported values for CdTe grown directly on lattice mismatched substrates, and is comparable to values for state-of-the-art CdTe grown on lattice matched CdZnTe substrates. The filtering efficiency for each set of dislocation filtering layers has been determined to be approximately 70%. This approach provides a promising pathway towards achieving hetero-epitaxy of high quality HgCdTe on large-area lattice-mismatched alternative substrates with a low dislocation density for the fabrication of next generation infrared detectors with features of lower cost and larger array format size.

在这项工作中，多组CdZnTe / CdTe应变层超晶格已被用作位错过滤层，以减少通过分子束外延（MBE）在GaSb（211）B衬底上生长的CdTe缓冲层的穿线位错并提高材料质量。 。通过结合CdZnTe / CdTe超晶格过滤结构，材料质量得到了显着改善，蚀刻坑密度低至1×10 ⁵  cm ^-2。证明了在GaSb上生长的CdTe，比先前报道的直接在晶格失配的衬底上生长的CdTe值低两个数量级，并且可与在晶格匹配的CdZnTe衬底上生长的最新CdTe值相比。已确定每组位错过滤层的过滤效率约为70％。该方法为在具有低位错密度的大面积晶格不匹配替代基板上实现高质量HgCdTe的异质外延提供了一条有希望的途径，以制造成本较低且阵列尺寸较大的下一代红外探测器。