Development of next generation far-infrared detector

我们已经为未来的中红外和远红外天文任务开发了锗离子探测器。为了在阻挡层和红外有源层之间获得清晰的界面，我们测试了两种新的方法，表面活化键合(SAB)和分子束外延(MBE)晶体生长。我们用SAB技术将纯硅片(载流子浓度为8×10^12/cc)与高掺杂硅片(Ga10^16/cc)连接在一起，制作了一种锗BIB探测器，该器件具有典型的BIB探测器的I-V特性，延长了截止波长，降低了暗电流。我们还用分子束外延技术在高掺杂硅片上生长了高纯锗晶体，其载流子浓度低到足以在BIB探测器中形成阻挡层(5×10~(-14)/cc)。

We have developed germanium BIB detector for future mid- and far-infrared astronomical missions. In order to obtain clear interface between blocking and IR active layers, we have tested two new methods, surface activated bonding (SAB) and molecular beam epitaxial (MBE) crystal growth. We have fabricated a germanium BIB detector with SAB technique bonding a pure wafer (carrier concentration <8x10^12/cc) and a highly doped wafer (Ga 10^16/cc) and found that that device had a typical I-V characteristic for BIB detector, extended cut-off wavelength, and reduction of dark current. We have also achieved a high-purity germanium crystal growth on a high doped wafer with MBE technique that have a carrier concentration low enough for a blocking layer in BIB detector (5x10^14/cc).