| 摘要 |
A HgCdTe film is produced on a CdTe substrate, by depositing HgTe on a CdTe substrate, and then illuminating the substrate from the underside with infrared light at a wavelength longer than the desired operating wavelength (band-gap-equivalent wavelength) of the device. Since CdTe is transparent in the infrared, the light will reach the HgTe/CdTe interface. Since HgTe is an absorber in the infrared, most of the infrared radiation will be absorbed near the interface, which will cause intense localized heating and thus accelerate the interdiffusion of HgTe and CdTe. This interdiffusion will have the effect of moving the interface away from the original location, and toward the film/air interface. Since the desired end-product HgCdTe composition will be transparent to the infrared radiation applied, the process is inherently self-limiting. By appropriately selecting the infrared wavelength applied, variously proportioned HgCdTe compositions may be obtained, so that the effective band gap of the device can be selected at will. Moreover, no surface damage is caused by this technique.
|
