Abstract:
A test circuit for fabrication of transistors for Very Large Scale Integration (“VLSI”) processing and method of use thereof are described. Transistors are formed in an array. A first decoder is coupled to gates of the transistors and configured to selectively pass voltage to the gates. A second decoder is coupled to drain regions of the transistors and configured to selectively pass voltage to the drain regions of the transistors. A third decoder is coupled to source regions of the transistors and configured to selectively pass voltage to the source regions of the transistors. A fourth decoder is coupled to body regions of the transistors and configured to selectively pass voltage to the body regions of the transistors.
Abstract:
An electrically erasable programmable read-only memory (“CMOS NON-VOLATILE MEMORY”) cell is fabricated using standard CMOS fabrication processes. First and second polysilicon gates are patterned over an active area of the cell between source and drain regions. Thermal oxide is grown on the polysilicon gates to provide an isolating layer. Silicon nitride is deposited between the first and second polysilicon gates to form a lateral programming layer.
Abstract:
At least one MOS parameter of a MOS fuse is characterized to provide at least one MOS parameter reference value. Then, the MOS fuse is programmed by applying a programming signal to the fuse terminals so that programming current flows through the fuse link. The fuse resistance is measured to provide a measured fuse resistance associated with a first logic value. A MOS parameter of the programmed MOS fuse is measured to provide a measured MOS parameter value. The measured MOS parameter value is compared to the reference MOS parameter value to determine a second logic value of the MOS fuse, and a bit value is output based on the comparison.
Abstract:
At least one MOS parameter of a MOS fuse is characterized to provide at least one MOS parameter reference value. Then, the MOS fuse is programmed by applying a programming signal to the fuse terminals so that programming current flows through the fuse link. The fuse resistance is measured to provide a measured fuse resistance associated with a first logic value. A MOS parameter of the programmed MOS fuse is measured to provide a measured MOS parameter value. The measured MOS parameter value is compared to the reference MOS parameter value to determine a second logic value of the MOS fuse, and a bit value is output based on the comparison.
Abstract:
E-fuses in an E-fuse memory array are programmed by applying a first programming pulse to a plurality of E-fuses to program the plurality of E-fuses to a first state; and then applying a second programming pulse to at least a selected E-fuse in the plurality of E-fuses to program the selected E-fuse to a second state.
Abstract:
A memory cell with a logic bit has a first one-time-programmable (“OTP”) memory element providing a first OTP memory element output and a second OTP memory element providing a second OTP memory element output. A logic operator coupled to the first OTP memory element output and to the second OTP memory element output and provides a binary memory output of the memory cell. In a particular embodiment, the first OTP memory element is a different type of OTP memory than the second OTP memory element.
Abstract:
An electronic fuse (“E-fuse”) cell is formed on a semiconductor substrate. The E-fuse cell has a fuse element with a fuse link extending from a first fuse terminal across a thick dielectric structure to a second fuse terminal. The first and second fuse terminals are separated from the semiconductor substrate by a thin dielectric layer.
Abstract:
A memory cell with a logic bit has a first one-time-programmable (“OTP”) memory element providing a first OTP memory element output and a second OTP memory element providing a second OTP memory element output. A logic operator coupled to the first OTP memory element output and to the second OTP memory element output and provides a binary memory output of the memory cell. In a particular embodiment, the first OTP memory element is a different type of OTP memory than the second OTP memory element.
Abstract:
A buried interconnect can be incorporated into the starting semiconductor on insulator wafer during the early stages of the circuit fabrication process flow for use with semiconductor devices. The buried interconnect provides an additional interconnect layer enabling an overall reduction in the silicon real estate occupied by interconnections. The buried interconnect has low resistance and can prevent the formation of unwanted PN junctions through the use of silicides. The buried interconnect and its fabrication method include an S0I wafer that has an oxidation layer formed on top of a semiconductor layer by oxidation, followed by an nitride layer formed on top of the oxide layer which then is selectively etched to form two trenches with regions of different depths. Some regions of the trenches are etched to remove all of the semiconductor layer in the trench to expose the buried oxide layer. In other regions, a thin layer of semiconductor is left at the bottom of the trenches. Next, all of the exposed surfaces of the trenches are oxidized and the oxide at the trench bottom is removed to expose the underlying semiconductor material. The underlying semiconductor material is then silicided to form a buried interconnect. The wafer, including the trenches, is subsequently covered with oxide and chemical-mechanical polishing is used to remove excess oxide outside the trenches.
Abstract:
An outer edge ring of a semiconductor wafer is polished to prevent delamination and peeling-off of at least one layer of material deposited near the outer edge of the semiconductor wafer during fabrication of integrated circuits. The semiconductor wafer is mounted on a wafer chuck, and the wafer chuck holding the semiconductor wafer is rotated such that the semiconductor wafer rotates. A polishing pad is moved toward the semiconductor wafer as the semiconductor wafer is rotating. The polishing pad has a polishing surface that faces and contacts the outer edge ring of the semiconductor wafer as the polishing pad is moved toward the semiconductor wafer to polish the outer edge ring of the semiconductor wafer. The outer edge ring has the at least one layer of material that is polished off by the polishing surface of the polishing pad. The polishing surface of the polishing pad may be tapered such that the edge of an upper layer of material that is disposed further from the semiconductor wafer is disposed more inward toward the center of the semiconductor wafer such that the upper layer of material is not likely to delaminate and peel-off away from a lower abutting layer of material on the semiconductor wafer. Furthermore, a photodetector may determine sufficient polishing of the outer edge ring of the semiconductor wafer.