Abstract: The present invention relates to a method for preparing, on a silicon wafer, an n+pp+ or p+nn+ structure which includes the following consecutive steps: a) on a p or n silicon wafer (1), which includes a front surface (8) and a rear surface (9), a layer of boron-doped silicon oxide (BSG) (2) is formed on the rear surface (9) by PECVD, followed by a SiOx diffusion barrier (3); b) a source of phosphorus is diffused such that the phosphorus and the boron co-diffuse and in order also to form: on the front surface (8) of the wafer obtained at the end of step a), a layer of phosphorus-doped silicon oxide (PSG) (4) and an n+ doped area (5); and on the rear surface of the wafer obtained at the end of step a), a boron-rich area (BRL) (6), as well as a p+ doped area (7); c) the layers of BSG (2) and PSG (4) oxides and SiOx (3) are removed, the BRL (6) is oxidized and the layer resulting from said oxidation is removed.

Abstract: The object of the invention is a process for P-type boron doping of silicon wafers placed on a support in the chamber of a furnace of which one end comprises a wall in which means for introducing reactive gases and a gas carrying a boron precursor in gaseous form are located, whereby said process comprises the stages that consist in: a) In the chamber, reacting the reactive gases with boron trichloride BCl3 that is diluted in the carrier gas at a pressure of between 1 kPa and 30 kPa, and a temperature of between 800° C. and 1100° C., for forming a boron oxide B2O3 glass layer, b) Carrying out the diffusion of atomic boron in silicon under an N2+O2 atmosphere at a pressure of between 1 kPa and 30 kPa. A furnace designed for the implementation of said doping process as well as its applications—the manufacturing of large boron-doped silicon slices, in particular for photovoltaic applications—is also claimed.

Abstract: The present invention relates to a method for preparing, on a silicon wafer, an n+pp+ or p+nn+ structure which includes the following consecutive steps: a) on a p or n silicon wafer (1), which includes a front surface (8) and a rear surface (9), a layer of boron-doped silicon oxide (BSG) (2) is formed on the rear surface (9) by PECVD, followed by a SiOx diffusion barrier (3); b) a source of phosphorus is diffused such that the phosphorus and the boron co-diffuse and in order also to form: on the front surface (8) of the wafer obtained at the end of step a), a layer of phosphorus-doped silicon oxide (PSG) (4) and an n+ doped area (5); and on the rear surface of the wafer obtained at the end of step a), a boron-rich area (BRL) (6), as well as a p+ doped area (7); c) the layers of BSG (2) and PSG (4) oxides and SiOx (3) are removed, the BRL (6) is oxidised and the layer resulting from said oxidation is removed.

Abstract: A process for P-type boron doping of silicon wafers placed on a support in the chamber of a furnace of whose one end includes a wall in which element for introducing reactive gases and a carrier gas carrying a boron precursor in gaseous form are located, whereby the process includes the following stages: a) reacting in the chamber, the reactive gases with boron trichloride BCl3 that is diluted in the carrier gas at a pressure of between 1 kPa and 30 kPa, and a temperature of between 800° C. and 1100° C., to form a boron oxide B2O3 glass layer; and b) carrying out the diffusion of atomic boron in silicon under an N2+O2 atmosphere at a pressure of between 1 kPa and 30 kPa. A furnace designed for implementing the doping process, and the manufacturing of large boron-doped silicon slices, in particular for photovoltaic applications are also claimed.

Abstract: Method and device for doping or diffusion, or oxidation of silicon wafers (4), the wafers being introduced into the chamber (2) of an oven (1) wherein is introduced at least a gas for performing the doping or diffusion or oxidation process. The method comprises simultaneously with the introduction and passage of gas into the chamber (2) of the oven (1), continuously subjecting the latter to a depression of constant value. The device comprises an oven (1) provided with a chamber (2) wherein are introduced the wafers, the oven including at least an inlet tube (5a, 5b, 5c) for introducing at least a gas into the chamber (2) to carry out the processes and at least an outlet tube (6) for extracting the gas whereto is connected a suction unit (7) for generating in the chamber (2) a constant and controlled depression.

Abstract: Device for automatically loading and unloading a feed to be treated in a heat treatment unit (1) such as a diffusion oven, comprising at least a cantilever (2) designed to receive the whole feed and to introduce the feed in the oven. The feed can consist of silicon wafers (4) arranged in quartz boats. The device comprises a multiple-basket automatic transfer equipment receiving on a reception zone, the whole feed, and transferring, from the reception zone to the cantilever, the whole feed and optionally dummy feeds, shielding feeds and control elements and vice-versa after the heat treatment, transferring the whole treated feed to the reception zone and transferring, from the cantilever to their original locations, the shielding feeds and the control elements, the various operations being carried out according to a predetermined scenario.

Abstract: The convertible pad support can receive at least two different types of pads of different dimensions. The support includes a three-dimensional structure defining a storage volume wherein the pads are disposed. The structure includes two lateral flanks which are firmly connected by two fixed arms and receives at least one additional arm which can be placed opposite the storage volume. The structure maintains the pads inside the storage volume with the aid of the other arms whereby the normal distance between the additional arm and the geometric longitudinal axis of one of the fixed arms can be adjusted in order to adapt support to the dimensions of the pads to be received.

Abstract: The invention concerns an electrostatic chuck (250) comprising an upper ceramic (205) bearing the substrate (200) to be treated and a lower ceramic (215) bearing heating elements (225) and radio frequency electrodes (220), said ceramics being permanently bonded together. Said ceramics are preferably bonded together by heated glass and the lower ceramic is fixedly assembled to a pedestal, for example through a soldered bonding.

Abstract: Device for automatically loading and unloading a feed to be treated in a heat treatment unit (1) such as a diffusion oven, comprising at least a cantilever (2) designed to receive the whole feed and to introduce the feed in the oven. The feed can consist of silicon wafers (4) arranged in quartz boats. The device comprises a multiple-basket automatic transfer equipment receiving on a reception zone, the whole feed, and transferring, from the reception zone to the cantilever, the whole feed and optionally dummy feeds, shielding feeds and control elements and vice-versa after the heat treatment, transferring the whole treated feed to the reception zone and transferring, from the cantilever to their original locations, the shielding feeds and the control elements, the various operations being carried out according to a predetermined scenario.

Abstract: Method and device for doping or diffusion, or oxidation of silicon wafers (4), the wafers being introduced into the chamber (2) of an oven (1) wherein is introduced at least a gas for performing the doping or diffusion or oxidation process. The method comprises simultaneously with the introduction and passage of gas into the chamber (2) of the oven (1), continuously subjecting the latter to a depression of constant value. The device comprises an oven (1) provided with a chamber (2) wherein are introduced the wafers, the oven including at least an inlet tube (5a, 5b, 5c) for introducing at least a gas into the chamber (2) to carry out the processes and at least an outlet tube (6) for extracting the gas whereto is connected a suction unit (7) for generating in the chamber (2) a constant and controlled depression.