Critical Radial Temperature Gradient Inducing Slip Dislocations in Silicon Epitaxy Using Dual Heating of the Two Surfaces of a Wafer
Abstract
Heating both wafer surfaces allowed us to efficiently control the radial temperature gradient, dT/dr, even for large wafers (150 mm diameter). With an epitaxial-growth apparatus using dual heating of the two surfaces of a wafer, the relation between inducing slip dislocations and the values of dT/dr were experimentally examined. It was found that it was necessary to keep the maximum temperature gradient lower than between 6 and 11°C/cm in order to accomplish slip-free epitaxy in the temperature ranges of 1100°C to 1250°C and at 930°C, respectively. The maximum shear stresses were calculated for the temperature distributions of each wafer by a finite-element computer model. It was concluded that the critical shear stress (inducing slip dislocations) was between 6× 106 and 9× 106 N/m2 in the temperature range between 1100 and 1250°C and at 930°C, respectively.
- Publication:
-
Japanese Journal of Applied Physics
- Pub Date:
- November 1986
- DOI:
- 10.1143/JJAP.25.1619
- Bibcode:
- 1986JaJAP..25.1619A