The manufacture of affordable second generation MCT detectors is favorably impacted by the availability of low-cost, large-area (Cd,Zn)Te substrates for LPE. We report here on our results in achieving routine production of high-quality, 4 cm X 6 cm, (Cd,Zn)Te substrates using scaled-up vertical Bridgman technology. Six kilogram ingots with diameters as large as 10 cm were produced. Substrate characteristics such as EPD, IR transmission, and precipitate morphology are reported. Substrate purity, which also impacts detector producibility, was monitored using GDMS of the starting elements, intermediate compounds, and the final ingots. Use of ultra-high purity starting materials enabled the Cu concentration in the substrate to be reduced significantly.