Abstract: A shallow junction that previously would require the use of a low-energy ion implanter can be directly formed by high-energy or middle-energy ion implanters such that the manufacturer need not purchase a new low-energy ion implanter. In one embodiment, an ion-implantation method for forming a shallow junction comprises providing a semiconductor substrate including at least one transistor structure. During ion implantation to form a shallow junction, a buffer layer is formed on the implantation region. The buffer layer has a predetermined thickness. Charged ions are implanted into the implantation region through the buffer layer by an energy provided by a middle-energy ion implanter, and the buffer layer is removed. The buffer layer is used for blocking the amount of the charged ions that will be implanted into the implantation region so as to form a shallow junction that would require a low-energy ion implanter without the buffer layer.

Abstract: In order to use an etching solution of less complicated composition for recovering used wafers, embodiments of the present invention provide a recovering method, and also provide a kind of wafer, which is used as a process control wafer or dummy wafer, and fabrication methods. In one embodiment, a wafer-recovering method comprises providing a first wafer, wherein the first wafer has a base, a first conductive layer on the base, and a second conductive layer on the first conductive layer. The method further comprises removing the first and second conductive layers with an acidic solution to obtain a second wafer; and washing the second wafer with a liquid. The second conductive layer is formed on the first conductive layer in a deposition process, and the first conductive layer is more easily removed by the acidic solution than the second conductive layer.

Abstract: A method for monitoring an ion implanter is disclosed. In one embodiment, the method comprises providing a wafer, forming a barrier layer on the surface of the wafer wherein the barrier layer has a substantial blocking effect on ion implantation, performing an ion implantation process to the wafer, performing a thermal treatment process, removing the barrier layer, and measuring a physical property of the wafer. The measured physical property of the wafer can be used to ascertain the status of the ion implanter. For instance, the measured physical property can be used to determine whether the ion implanter has problems when the energy or concentration of the implanted ions is changed.

Abstract: In order to use an etching solution of less complicated composition for recovering used wafers, embodiments of the present invention provide a recovering method, and also provide a kind of wafer, which is used as a process control wafer or dummy wafer, and fabrication methods. In one embodiment, a wafer-recovering method comprises providing a first wafer, wherein the first wafer has a base, a first conductive layer on the base, and a second conductive layer on the first conductive layer. The method further comprises removing the first and second conductive layers with an acidic solution to obtain a second wafer; and washing the second wafer with a liquid. The second conductive layer is formed on the first conductive layer in a deposition process, and the first conductive layer is more easily removed by the acidic solution than the second conductive layer.

Abstract: A shallow junction that previously would require the use of a low-energy ion implanter can be directly formed by high-energy or middle-energy ion implanters such that the manufacturer need not purchase a new low-energy ion implanter. In one embodiment, an ion-implantation method for forming a shallow junction comprises providing a semiconductor substrate including at least one transistor structure. During ion implantation to form a shallow junction, a buffer layer is formed on the implantation region. The buffer layer has a predetermined thickness. Charged ions are implanted into the implantation region through the buffer layer by an energy provided by a middle-energy ion implanter, and the buffer layer is removed. The buffer layer is used for blocking the amount of the charged ions that will be implanted into the implantation region so as to form a shallow junction that would require a low-energy ion implanter without the buffer layer.

Abstract: A method for monitoring an ion implanter is disclosed. In one embodiment, the method comprises providing a wafer, forming a barrier layer on the surface of the wafer wherein the barrier layer has a substantial blocking effect on ion implantation, performing an ion implantation process to the wafer, performing a thermal treatment process, removing the barrier layer, and measuring a physical property of the wafer. The measured physical property of the wafer can be used to ascertain the status of the ion implanter. For instance, the measured physical property can be used to determine whether the ion implanter has problems when the energy or concentration of the implanted ions is changed.

Abstract: A method for stabilizing a degas temperature of wafers in a degas chamber comprises (a) setting an electrical heater at an initial output power, (b) heating each wafer for a first period of time to keep the temperature of the wafer at a predetermined range by setting the electrical heater at a first output power equal to or higher than the initial output power, (c) heating the wafer for a second period of time to increase the temperature of the wafer to a predetermined value by raising the output power of the electrical heater to a second output power; and (d) heating the wafer for a third period of time by reducing the output power of the electrical heater to a third output power. The method lessens the “first wafer effect” and the “temperature-accumulated effect”. Therefore, the temperature of the wafers can be well controlled before a subsequent sputtering process.