Method for treating a semi-conductor substrate by thermal activation of light elements

摘要

The process comprises performing a first annealing of a substrate made of a p-type crystalline silicon semi-conductor comprising four light elements at a temperature T1 (680[deg] C) corresponding to a thermal activation temperature of a first light element, performing a second annealing of the substrate at a temperature T2 (600[deg] C) corresponding to a thermal activation temperature of a second light element, and performing a third annealing of the substrate at a temperature T3 (500[deg] C) corresponding to a thermal activation temperature of a third light element. The process comprises performing a first annealing of a substrate made of a p-type crystalline silicon semi-conductor comprising four light elements at a temperature T1 (680[deg] C) corresponding to a thermal activation temperature of a first light element, performing a second annealing of the substrate at a temperature T2 (600[deg] C) corresponding to a thermal activation temperature of a second light element, performing a third annealing of the substrate at a temperature T3 (500[deg] C) corresponding to a thermal activation temperature of a third light element, and performing a fourth annealing of the substrate at a temperature T4 (450[deg] C) corresponding to a thermal activation temperature of a fourth light element. The semi-conductor material is expressed as Si xA y, where x is a positive number, y is a positive number and A is a chemical element or a compound of chemical elements of the fourteenth column of periodic table. Each annealing steps comprises maintaining the temperatures T1, T2, T3 or T4 for a determined period of time, where the temperatures are expressed as T1 greater than T2 greater than T3 greater than T4. After the completion of the fourth annealing: a fifth annealing of the substrate is performed at a temperature T5 corresponding to a thermal activation temperature of a fifth type of light element present in the semi-conductor different from four other types of light elements, where T5 is less than T4; a sixth annealing of the substrate is performed at a temperature T6 corresponding to a thermal activation temperature of a sixth type of light element present in the semi-conductor different from five other types of light elements, where T6 is less than T5; a seventh annealing of the substrate is performed at a temperature T7 corresponding to a thermal activation temperature of seventh type of light element different from six other types of light elements, where T7 is less than T6; and an eighth annealing of the substrate is performed at a temperature T8 corresponding to a thermal activation temperature of eighth type of light element present in the semi-conductor different from seven other types of light elements, where T8 is less than T7. One of the annealing is carried out in a lamp furnace in which the substrate is placed and on an ingot of semi-conductor, under an atmosphere of oxygen, nitrogen, hydrogen, argon and/or helium, where the substrate is obtained by cutting a portion of the ingot. An independent claim is included for a process for producing a semiconductor device from a substrate made of semi-conductor.