If you are mentioning the area which is used to freeze something in the refrigerator, the area is called "冷冻室", the other areas outside "冷冻室" is called "冷藏室" where is used to preserve something.
With regard to "冰柜", it's more like of a big chest with a sliding door on the top, usually be placed in a convenience shop, supermarket, small restaurant, etc. It has a larger volume than the refrigerator in house.