Large angle ion implantation method
Patent 5223445 Issued on June 29, 1993. Estimated Expiration Date: 
May 30, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
May 30, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.InventorAssigneeApplicationNo. 707801 filed on 05/30/1991US Classes:438/302, Oblique implantation257/E21.335, In Group IV semiconductor (EPO)257/E21.336, Of electrically active species (EPO)257/E21.345, Characterized by the angle between the ion beam and the crystal planes or the main crystal surface (EPO)257/E21.433, Where the source and drain or source and drain extensions are self-aligned to sides of gate (EPO)438/525, Using oblique beam438/528, Providing nondopant ion (e.g., proton, etc.)438/798Ionized irradiation (e.g., corpuscular or plasma treatment, etc.)ExaminersPrimary: Chaudhuri, OlikAssistant: Ojan, Ourmazd S. Attorney, Agent or FirmForeign Patent References
International ClassesH01L 021/336H01L 021/425 Foreign Application Priority Data1990-05-30 JPAbstractAn ion implanting method which suppresses defects by changing the shape of the amorphous layer formed by ion injection from that of a conventional device.After forming a mask pattern on a semiconductor wafer, amorphous layers are then formed with sufficient penetration under the mask material by implanting ions at an implant angle greater than or equal to 20 degrees with a dose amount enough for forming amorphous layers. In this large angle ion implanting method, the edge of each amorphous layer becomes dull and, thereby, no voids are formed in a successive heat treatment.Other References
| |
