Method for manufacturing a semiconductor device having hemispherical grains

A method for manufacturing semiconductor devices, comprising:

• maintaining a plurality of wafers loaded in a boat in a chamber at a first vacuum pressure level and at a first temperature, wherein said wafers comprise a plurality of patterned lower electrodes;
• raising said first temperature in said chamber to a greater, second temperature;
• supplying a silicon source gas from a plurality of nozzles extending in different directions to an interior of said chamber containing said wafers, wherein each nozzle has a plurality of spaced apart spray openings supplying the silicon source gas, and the diameter of the spray openings increases as the openings approach top terminal ends of the nozzle;
• reducing pressure in said chamber from the first vacuum pressure level to a second vacuum pressure level less than said first vacuum pressure level, by means of a first pump;
• and
• subsequently, further reducing said pressure in said chamber to a third vacuum pressure level lower than the second vacuum pressure level by means of a turbo molecular pump under conditions effective to produce semiconductor devices each having HSG silicon nuclei formed on a patterned lower electrode of a capacitor of each of said semiconductor devices.