Method for manufacturing semiconductor devices using heat-treatment vertical reactor with temperature zones

A method for manufacturing semiconductor devices comprising steps of:

• introducing a wafer or wafers into a vertical thermal reactor from its lower end;
• heating by a first electric heating means a first region of the vertical thermal reactor to a first temperature, said first region extending over a first depth;
• heating by a second electric means a second region of the vertical thermal reactor to a second temperature higher than the first temperature, said second region situated above the first region, extending over a second depth;
• setting a temperature gradient in an intermediate region between the first and second regions, which intermediate region separating the first and second electric heating means from one another;
• maintaining said first temperature, said second temperature and said temperature gradient simultaneously in the vertical reactor in the steps set forth below;
• subjecting the wafer or wafers to a first heat treatment for manufacturing the semiconductor devices on said wafer or wafers in said first region of the vertical thermal reactor at the first temperature;
• bringing a gas of the first heat treatment into contact with the wafer or wafers during said first heat treatment;
• withdrawing the gas of the first heat treatment from a port provided in the intermediate region or in at least one of the first and second regions in the vicinity of the intermediate region, while essentially preventing invasion of the gas of the first heat treatment into said second region;
• moving the wafer or wafers upwards from the first region to the second region through the intermediate region having said temperature gradient;
• subjecting the wafer or wafers to a second heat treatment for manufacturing the semiconductor devices on the wafer or wafers in the second region of the vertical thermal reactor;
• reverting the wafer or wafers from the second region to the first region through the intermediate region having said temperature gradient;
• and,
• adjusting a staying time of the wafer or wafers in the first region, which wafer or wafers reverted to the first region, to a time which is at least so long not to cause slip lines on the wafer or wafers.

A method for manufacturing semiconductor devices comprising steps of:

• introducing a wafer or wafers into a vertical thermal reactor from its lower end;
• heating by an electric heating means a first region of the vertical thermal reactor to a first temperature, said first region extending over a first depth;
• heating by another electric means a second region of the vertical thermal reactor, said second region extending over a second depth and having a second temperature higher than the first temperature;
• shielding and absorbing heat from both first and second electric heating means and establishing a temperature gradient in an intermediate region between the first region and the second region;
• maintaining said first temperature, said second temperature and said temperature gradient simultaneously in the vertical reactor in the steps set forth below;
• subjecting the wafer or wafers to a first heat treatment for manufacturing the semiconductor devices on said semiconductor wafer or wafers in said first region of the vertical thermal reactor at the first temperature;
• moving the wafer or wafers upwards from the first region to the second region through said intermediate region having said temperature gradient;
• subjecting the wafer or wafers to a second heat treatment for manufacturing the semiconductor devices on said semiconductor wafer or wafers in the second region of the vertical thermal reactor at the second temperature;
• reverting the wafer or wafers to the first region having the first temperature through said intermediate region;
• and,
• adjusting a staying time of the wafer or wafers in the first region, which wafer or wafers reverted to the first region, to a time which is at least so long not to cause slip lines on the wafer or wafers.