Development of a thermoelectrically cooled IV-VI semiconductor diode laser using epitaxial lift-off techniques.

摘要

IV-VI semiconductor (lead-salt) lasers are well suited for infrared spectroscopy as the light emission covers the 3 ;A potential solution to the operating temperature problem is to employ epitaxial lift-off techniques in order to transfer the semiconductor device from its thermally resistive substrate to copper, a superior thermal conductor. Finite element thermal models predict this transfer will increase the operating temperature by 63;This dissertation presents thermal models showing the dramatic increase in operating temperature gained by transferring the laser structure. Also, significant progress towards constructing a copper mounted IV-VI semiconductor laser by means of a new patented fabrication procedure is documented. This dissertation contains scanning electron microscopy micrographs showing cleaved epilayer structures mounted on copper. Supporting data of non-linear current versus voltage scans and x-ray diffraction peaks of lifted-off epilayers without degradation of crystal quality are included.;Thermoelectric cooling (TEC) modules can provide a heat sink temperature of 220 K. If a IV-VI semiconductor laser could operate in continuous wave mode while mounted on a TEC module, an electrically cooled spectrometer could be developed. Using molecular beam epitaxy and modern photolithography techniques, a 1995 PbEuSeTe/PbTe separate confinement buried heterostructure laser operated in continuous wave mode at a heat sink temperature of 223 K. This does not leave a sufficient temperature tuning range for spectroscopic applications, suggesting new approaches to the problem should be investigated.