摘要:
An electrostatic discharge protection device and method decreases the latch-up susceptibility of an ESD structure by suppressing the injection of minority carriers that cause transistor action to occur. This is accomplished, for example, by using a metal contact to the n-substrate or n-well in place of or in parallel with the prior art p-diffusion. Using such metal contact forms a Schottky Barrier Diode (SBD) with the ESD structure. Since the SBD is a majority-carrier device, negligible minority carriers are injected when the SBD is in forward bias, thereby reducing the likelihood of latch-up.
摘要:
An electrostatic discharge protection device and method decreases the latch-up susceptibility of an ESD structure by suppressing the injection of minority carriers that cause transistor action to occur. This is accomplished, for example, by using a metal contact to the n-substrate or n-well in place of or in parallel with the prior art p-diffusion. Using such metal contact forms a Schottky Barrier Diode (SBD) with the ESD structure. Since the SBD is a majority-carrier device, negligible minority carriers are injected when the SBD is in forward bias, thereby reducing the likelihood of latch-up.
摘要:
A method for fabrication of a buried field shield (64) in a semiconductor substrate. A seed substrate is prepared by depositing an epitaxial layer (54) onto a seed wafer (80) and then depositing a heavily doped layer (56) and a thin dielectric (58). The thin dielectric is patterned for contact holes and then a conductive field shield (64) is deposited and patterned. A thick quartz layer (66) is deposited over the field shield and dielectric. A mechanical substrate (68) is anodically bonded to the quartz (66) of the seed substrate and the original seed wafer (80) is etched back to expose the epitaxial layer (54) for further fabrication of integrated electronic devices therein.
摘要:
A precision analog metal-metal capacitor is fabricated by forming a first capacitor plate in an insulation layer by forming a trench therein, depositing metal within the trench and planarizing the device. A thin dielectric layer is then deposited and patterned over the first capacitor plate. A second insulator is then deposited over the device and discrete openings etched therein to expose the insulation layer and first metal plate. Metal is deposited within the openings and planarized, thereby forming a contact to the first metal plate and the second metal plate of the capacitor.
摘要:
A programmable storage element for redundancy-programming includes a programmable antifuse circuit which includes a plurality of first resistors (F1a, F1b, F1c) and a switching circuit (Q Fa , Q Fb , Q Fc , Q Fd ) for coupling the first resistors in series in response to a plurality of first control signals (Ta, Tb, Tc, Td) and for coupling the first resistors in parallel in response to a plurality of second control signals to permit programming of the first resistors, and a sensing circuit for determining whether or not the first resistors have been programmed. The state of the first resistors is determined by comparing a first voltage drop across the first resistors with a second voltage drop across a second resistor. Each of the first resistors is an unsilicided polysilicon conductor which has an irreversible resistance decrease when a predetermined threshold current is applied for a minimum period of time.
摘要:
A method for fabrication of a buried field shield (64) in a semiconductor substrate. A seed substrate is prepared by depositing an epitaxial layer (54) onto a seed wafer (80) and then depositing a heavily doped layer (56) and a thin dielectric (58). The thin dielectric is patterned for contact holes and then a conductive field shield (64) is deposited and patterned. A thick quartz layer (66) is deposited over the field shield and dielectric. A mechanical substrate (68) is anodically bonded to the quartz (66) of the seed substrate and the original seed wafer (80) is etched back to expose the epitaxial layer (54) for further fabrication of integrated electronic devices therein.
摘要:
A metal interconnect having a high conductivity and high resistance to metal migration failure is formed of two layers of metal or alloy (15,17) (such as TI/CuAlSi) with a dielectric (16) interposed therebetween and a connection made between the layers (15,17) by a conductive material, preferably in the form of a plug or stud (14) formed in an aperture of an inter-level dielectric, at ends of the interconnect. A high precision metal-to-metal capacitor can be formed from the same layers (15,17) by forming separate connections to each of the layers. The topography of the interconnect (and capacitor) is of reduced severity and facilitates planarization of an overlying inter-level dielectric.
摘要:
A method of forming integrated circuit chips including two dissimilar type NFETs and/or two dissimilar type PFETs on the same chip, such as both thick and thin gate oxide FETs. A DRAM array may be constructed of the thick oxide FETs and logic circuits may be constructed of the thin oxide FETs on the same chip. First, a gate stack including a first, thick gate SiO2 layer is formed on a wafer. The stack includes a doped polysilicon layer on the gate oxide layer, a silicide layer on the polysilicon layer and a nitride layer on the silicide layer. Part of the stack is selectively removed to re-expose the wafer where logic circuits are to be formed. A thinner gate oxide layer is formed on the re-exposed wafer. Next, gates are formed on the thinner gate oxide layer and thin oxide NFETs and PFETs are formed at the gates. After selectively siliciding thin oxide device regions, gates are etched from the stack in the thick oxide device regions. Finally, source and drain regions are implanted and diffused for the thick gate oxide devices.
摘要:
A metal interconnect having a high conductivity and high resistance to metal migration failure is formed of two layers of metal or alloy (such as TI/cuAlsi) with a dielectric interposed therebetween and a connection made between the layers by a conductive material, preferably in the form of a plug or stud formed in an aperture of an inter-level dielectric, at ends of the interconnect. A high precision metal-to-metal capacitor can be formed from the same layers by forming separate connections to each of the layers. The topography of the interconnect (and capacitor) is of reduced severity and facilitates planarization of an overlying inter-level dielectric.