In previous Bridgman growth of CuInSe2 ingots, weighted amounts of high purity materials are introduced together into
quartz ampoules. During the initial heating, vigorous reaction occurs mainly between In and Se leading to a sudden
increase in the temperature and hence the vapor pressure. Explosion often occurs when the total amount of materials
exceeds 10 grams even with quartz ampoules with a wall thickness greater than 1 mm. Although the explosion can be
avoided by having very slow initial heating rate, the total materials are still limited to 30 g or less for each growth run.
Due to the limited materials, the dimensions of ingots grown in the previous experiments have been limited. In the
present work, we have developed a method to control the reaction between Se and In in the initial heating stage and
hence to reduce the rate of heat release in the exothermic reaction. Using this improved method, the limit on the material
amounts can be increased. Crystalline ingots with a total weight of 300 g and diameter 3 cm have been grown.
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