High quality ZnS0.06Se0.94 epilayer which was lattice-matched to GaAs substrate has been prepared. The sulfur composition x was 0.06 has been determined by EPMA. The FWHM of X-ray diffraction was 187.2 arcsec. ITO film formed by thermal evaporated In-Sn alloy first, then annealing in O2 atmosphere. The conductivity and transparency of ITO have been trade-off at acceptable parameter. Because of the highest current in I-V characteristic in the structure of ITO/ZnS0.06Se0.94:N, we optimized the annealing temperature and time at 450C for 60min in O2 atmosphere. Because of the excellent transparency and conductivity in the structure of ITO/Glass, we optimized the annealing temperature and time at 650C for 60min in O2 atmosphere. In this study, ITO/ZnS0.06Se0.94:Cl/ZnSe/ZnS0.06Se0.94:N/GaAs:Zn/Au- Zn double heterojunction (DH) structure has been prepared after annealing In- Sn/ZnS0.06Se0.94:Cl/ZnSe/ZnS0.06Se0.94:N/GaAs:Zn/Au- Zn in O2 atmosphere. I-V characteristic of DH junction structure shows a diode electric property.