Patent EP-2747126-A1 (EP)
Inventor: FOURNEL FRANK
IPC: C23C16/44
Filed: 2013-12-17
Abstract: The method for recycling a substrate holder (1) having a receiving surface adapted to receive a substrate for a step of depositing a layer of material on the substrate leading to the deposition of the layer of material on the substrate holder, comprises: introducing ionic species through the receiving surface of the holder so as to form a buried embrittlement plane defining a buried thin film (7) in the receiving surface of the holder; exfoliating the thin film of the holder so as to break up the thin film; and removing a stack (6) comprising a layer of material deposited on the thin film. The method for recycling a substrate holder (1) having a receiving surface adapted to receive a substrate for a step of depositing a layer of material on the substrate leading to the deposition of the layer of material on the substrate holder, comprises: introducing ionic species through the receiving surface of the holder so as to form a buried embrittlement plane defining a buried thin film (7) in the receiving surface of the holder; exfoliating the thin film of the holder so as to break up the thin film; and removing a stack (6) comprising the layer of material deposited on the thin film resulting from the step of depositing the layer of material on the substrate. The method further comprises, forming an additional layer on the thin film of the holder after the introducing step, depositing a surface layer on the thin film and on the stack of the layer of a material deposited on thin film, and thermal pretreatment for the growth of the number and size of cavities after the introducing step and before the exfoliation step. The removing step comprises peeling the additional layer, and cleaning the surface of the holder by pressurized water jet. The exfoliation step includes application of a heat treatment. The introducing step leads to the formation of cavities defining the thin film. A material of the surface layer presents a coefficient of thermal expansion (CTE) different from the CTE of a material of the holder. The receiving surface of the holder comprises a plane main area to receive the substrate and a peripheral region including an extra thickness material to maintain the substrate for depositing the layer of material. The introducing step includes introducing the ionic species through the peripheral region so that the embrittlement plane delimits the thin film under the peripheral region, and is carried out through the plane main area and through the peripheral region leading to the formation of the embrittlement plane under the plane main area and the formation of a second buried embrittlement plane under the peripheral region. The depositing step is carried out before the exfoliation step. The exfoliation step is realized when the thickness of the stack is 1-7 mu m. The holder comprises a silicon plate having diameter of 300 mm and the peripheral region having a thickness 725 mu m and a width of 5 mm to 5 cm. The holder is adapted for handling the silicon substrate having a diameter of 200 mm and for depositing the layer of a material made of titanium dioxide and having a thickness of 1.5 mu m. The introducing step comprises a hydrogen establishment with an energy of 1-300keV and an amount of 1x 10 1> 5>-1x 10 1> 7> at/cm 2>. The exfoliation step is carried out at a temperature of 200-500[deg] C for few minutes to a few hours.