Abstract: An identification circuit for establishing and sensing the state of a fusible element used in on chip identification of the chip's type comprising: a circuit establishing control signals for turning the identification circuit on and off; dual paths energized by the control signals generated by the level setting circuit to energize one path through the fusible element to provide a state level and the other path through a reference path which provides a reference voltage level which is distinguishable from both the blown and unblown states of the fusible element; a differential sensing circuit for comparing the reference voltage level to the state level to provide a signal indicating the state of the fusible element; and protection circuitry to protect the circuit during an operation in which the state of the fusible element is set.

Abstract: A silicon-on-insulation (SOI) body contact is formed within a device region of an SOI substrate so that no space of the SOI substrate is wasted for implementing a body contact. The body contact is formed by epitaxially growing silicon and depositing polysilicon. An electrical device can be formed to overlie the body contact. Thus, no additional circuitry or conductive path is required to electrically connect a body contact and a device region. Also, the body contact provides a predictable electrical characteristics without sacrificing the benefits attained from using the SOI substrate and conservation surface space on the semiconductor die.

Abstract: A silicon-on-insulation (SOI) body contact is formed within a device region of an SOI substrate so that no space of the SOI substrate is wasted for implementing a body contact. The body contact is formed by epitaxially growing silicon and depositing polysilicon. An electrical device can be formed to overlie the body contact. Thus, no additional circuitry or conductive path is required to electrically connect a body contact and a device region. Also, the body contact provides a predictable electrical characteristics without sacrificing the benefits attained from using the SOI substrate and conservation surface space on the semiconductor die.

Abstract: An SOI substrate contact is provided to the bodies of transistors fabricated in an SOI silicon wafer by selectively making the insulating layer below the bodies leaky. This is achieved by implanting below a set of transistor body locations a dose of ions having an energy such that the implanted region extends vertically through the buried insulator between the body and the wafer substrate, after which a voltage is applied sufficient to break down the oxide and establish a conductive path between the body and the substrate.

Abstract: An improved fuse structure in an integrated circuit (IC) structure is made by forming a gate stack comprised of layers of polysilicon and a silicide. Subsequent to the formation of the silicide layer, an etch stop silicon nitride layer is deposited over the silicide layer. The silicon nitride layer is patterned to expose the silicide layer. A soft passivation layer is deposited over the exposed silicide layer. The soft passivation layer has a low thermal conductivity which confines energy in the silicide layer, minimizing the current needed to program the fuse. The inherent ductility of the soft passivation layer prevents the generation of cracks in the surrounding layers.

Abstract: A fuse for semiconductor devices, in accordance with the present invention, includes a cathode formed from a first material, an anode formed from a second material and a fuse link connecting the cathode and the anode and formed from the second material. The second material is more susceptible to material migration than the first material when the fuse is electrically active such that material migration is enhanced in the second material.

Abstract: A patterned buried insulator is formed beneath the source and drain by forming a mask over the body area and implanting a dose of n or p type ions in the areas where the source and drains will be formed, then etching the STI and etching out the implanted area. A light oxidation is followed by a conformal oxide deposition in the STI and also in the etched area, thereby forming the buried oxide only where desired.

Abstract: An improved fuse structure in an integrated circuit (IC) structure is made by forming a gate stack comprised of layers of polysilicon and a silicide. Subsequent to the formation of the silicide layer, an etch stop silicon nitride layer is deposited over the silicide layer. The silicon nitride layer is patterned to expose the silicide layer. A soft passivation layer is deposited over the exposed silicide layer. The soft passivation layer has a low thermal conductivity which confines energy in the silicide layer, minimizing the current needed to program the fuse. The inherent ductility of the soft passivation layer prevents the generation of cracks in the surrounding layers.

Abstract: A patterned buried insulator is formed beneath the source and drain by forming a mask over the body area and implanting a dose of n or p type ions in the areas where the source and drains will be formed, then etching the STI and etching out the implanted area. A light oxidation is followed by a conformal oxide deposition in the STI and also in the etched area, thereby forming the buried oxide only where desired.

Abstract: A method of connecting a trench capacitor in a dynamic random access memory (DRAM) cell. First, trenches are formed in a silicon substrate using a masking layer including a pad nitride layer on a pad oxide layer. Trench capacitors are formed in the trenches. A buried strap is formed in each trench on the capacitor. The nitride pad layer is pulled back from the trench openings, exposing the pad oxide layer and any strap material that may have replaced the pad oxide layer around the trenches. The straps and trench sidewalls are doped to form a resistive connection. During a subsequent shallow trench isolation (STI) process, which involves an oxidation step, the exposed strap material on the surface of the silicon surface layer forms oxide unrestrained by pad nitride without stressing the silicon substrate.

Abstract: A test structure and method for determining DRAM cell leakage. The cell leakage test structure includes a pair of buried strap test structures. Each buried strap test structure includes multiple trench capacitors formed in a silicon body. Each trench capacitor is connected to a trench sidewall diffusion by at least one buried strap. An n-well ring surrounds each buried strap test structure and divides the buried strap test structure into two separate array p-wells, one being a contact area and the other a leakage test area. The contact area includes contacts to the trench capacitor plates for the corresponding buried strap test structure. In one buried strap test structure, a layer of polysilicon, essentially covers the trench capacitors in the leakage test area to block source/drain region formation there. The other of the two buried strap test structures includes polysilicon lines simulating wordlines with source and drain regions form on either side.

Abstract: A fuse for semiconductor devices, in accordance with the present invention, includes a cathode including a first dopant type, and an anode including a second dopant type where the second dopant type is opposite the first dopant type. A fuse link connects the cathode and the anode and includes the second dopant type. The fuse link and the cathode form a junction therebetween, and the junction is configured to be reverse biased relative to a cathode potential and an anode potential. A conductive layer is formed across the junction such that current flowing at the junction is diverted into the conductive layer to enhance material migration to program the fuse.