Development of next generation far-infrared detector

我们开发了锗BIB探测器，用于未来的中、远红外天文任务。为了获得阻断层和红外活性层之间清晰的界面，我们测试了两种新方法：表面活化键合（SAB）和分子束外延（MBE）晶体生长。我们利用SAB技术在载流子浓度<8 × 10^12/cc的纯晶片和高掺杂晶片（Ga 10^16/cc）上结合制备了锗BIB探测器，发现该器件具有BIB探测器典型的I-V特性，延长了截止波长，减小了暗电流。我们还利用MBE技术在高掺杂晶片上实现了高纯度锗晶体的生长，该晶片的载流子浓度足够低，可以在BIB探测器中形成阻挡层（5x10^14/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).