Abstract: A method for forming deep trench or via airgaps in a semiconductor substrate is disclosed comprising the steps of patterning a hole in the substrate, partly fill said hole with a sacrificial material (e.g. poly-Si), depositing spacers on the sidewalls of the unfilled part of the hole (e.g. TEOS) to narrow the opening, removing through said narrowed opening the remaining part of the sacrificial material (e.g. by isotropic etching) and finally sealing the opening of the airgap by depositing a conformal layer (TEOS) above the spacers. The method of forming an airgap is demonstrated successfully for use as deep trench isolation structures in BiCMOS devices.
Type:
Grant
Filed:
January 31, 2005
Date of Patent:
July 8, 2008
Assignee:
Interuniversitair Microelektronica Centrum vzw (IMEC)
Abstract: A semiconductor device includes a first polycrystalline semiconductor gate electrode structure formed in a first device region of a substrate via a gate insulation film and having a stacked structure in which a lower polycrystalline semiconductor layer and an upper polycrystalline semiconductor layer are stacked consecutively, the first polycrystalline gate electrode structure being doped to the second conductivity type, a second polycrystalline semiconductor gate electrode structure formed in a second device region of the substrate via a gate insulation film and having a stacked structure in which a lower polycrystalline semiconductor layer and an upper polycrystalline semiconductor layer are stacked consecutively, the second polycrystalline gate electrode structure being doped to the first conductivity type, a pair of diffusion regions of the second conductivity type formed in the first device region at respective lateral sides of the first polycrystalline semiconductor gate electrode structure, and a pair
Abstract: A triple-well CMOS structure having reduced latch-up susceptibility and a method of fabricating the structure. The method includes forming a buried P-type doped layer having low resistance under the P-wells and N-wells in which CMOS transistors are formed and forming a gap in a buried N-type doped layer formed in the P-wells, the is gap aligned under a contact to the P-well. The buried P-type doped layer and gap in the buried N-type doped layer allow a low resistance hole current path around parasitic bipolar transistors of the CMOS transistors.
Type:
Grant
Filed:
March 8, 2007
Date of Patent:
April 15, 2008
Assignee:
International Business Machines Corporation
Inventors:
Delbert R. Cecchi, Toshiharu Furukawa, Jack Allan Mandelman
Abstract: Semiconductor devices can be fabricated using conventional designs and process but including specialized structures to reduce or eliminate detrimental effects caused by various forms of radiation. Such semiconductor devices can include the one or more parasitic isolation devices and/or buried guard ring structures disclosed in the present application. The introduction of design and/or process steps to accommodate these novel structures is compatible with conventional CMOS fabrication processes, and can therefore be accomplished at relatively low cost and with relative simplicity.
Abstract: Provided is an electrostatic discharge (ESD) protection circuit using a silicon controlled rectifier (SCR), which is applied to a semiconductor integrated circuit (IC). A semiconductor substrate has a triple well structure such that a bias is applied to a p-well corresponding to a substrate of a ggNMOS device. Thus, a trigger voltage of the SCR is reduced. In addition, two discharge paths are formed using two SCRs including PNP and NPN bipolar transistors. As a result, the ESD protection circuit can have greater discharge capacity.
Type:
Grant
Filed:
December 5, 2005
Date of Patent:
March 11, 2008
Assignee:
Electronics and Telecommunications Research Institute
Inventors:
Kwi Dong Kim, Chong Ki Kwon, Jong Dae Kim
Abstract: In a first aspect, a first apparatus is provided. The first apparatus is a semiconductor device on a substrate that includes (1) a first metal-oxide-semiconductor field-effect transistor (MOSFET); (2) a second MOSFET coupled to the first MOSFET, wherein portions of the first and second MOSFETs form first and second bipolar junction transistors (BJTs) which are coupled into a loop; and (3) a conductive region that electrically couples a source diffusion region of the first or second MOSFET with a doped well region below the source diffusion region. The conductive region is adapted to prevent an induced current from forming in the loop. In another aspect, a design structure embodied in a machine readable medium for designing manufacturing, or testing a design is provided. Numerous other aspects are provided.
Type:
Application
Filed:
October 31, 2007
Publication date:
March 6, 2008
Applicant:
INTERNATIONAL BUSINESS MACHINES CORPORATION
Abstract: Latchup is prevented from occurring accompanying increasingly finer geometries of a chip. NchMOSFET N1 and PchMOSFET P1 form a CMOS circuit including: NchMOSFET N2 whose gate, drain and back gate are connected to back gate of N1 and PchMOSFET P2 whose gate, drain and back gate are connected to back gate of P1. Source of N2 is connected to source of N1. Source of P2 is connected to source of P1. N2 is always connected between the grounded source of N1 and the back gate of N1, while P2 is connected between source of P1 connected to a power supply and the back gate of P1. Each of N2 and P2 functions as a voltage limiting element (a limiter circuit).
Abstract: A semiconductor device suitable for applications in an electrostatic discharge (ESD) protection circuit, including a semiconductor substrate, a first well formed in the substrate, a second well formed in the substrate, and a first doped region formed in the second well, wherein the first well, the second well, and the first doped region collectively form a parasitic bipolar junction transistor (BJT), and wherein the first well is the collector of the BJT, the second well is the base of the BJT, and the first doped region is the emitter of the BJT.
Abstract: A semiconductor device includes first, second, and third wells. The first well is connected to a pad to which an external pin is connected and includes a first-type diffusion region that receives a well bias voltage. The second well is adjacent to the first well, and includes an insulating region and a second-type diffusion region outside the insulating region. The third well is adjacent to the second well and includes a first-type diffusion region that receives a first voltage. The insulating region inside the second well along with the first-type well diffusion region of the first well constitute a bipolar junction transistor that cuts off current flowing from the first well to the third well.
Abstract: Semiconductor structures and methods for suppressing latch-up in bulk CMOS devices. The semiconductor structure comprises a shaped-modified isolation region that is formed in a trench generally between two doped wells of the substrate in which the bulk CMOS devices are fabricated. The shaped-modified isolation region may comprise a widened dielectric-filled portion of the trench, which may optionally include a nearby damage region, or a narrowed dielectric-filled portion of the trench that partitions a damage region between the two doped wells. Latch-up may also be suppressed by providing a lattice-mismatched layer between the trench base and the dielectric filler in the trench.
Type:
Application
Filed:
June 18, 2007
Publication date:
October 18, 2007
Applicant:
INTERNATIONAL BUSINESS MACHINES CORPORATION
Inventors:
Toshiharu Furukawa, Robert Gauthier, David Horak, Charles Koburger, Jack Mandelman, William Tonti
Abstract: A triple-well CMOS structure having reduced latch-up susceptibility and a method of fabricating the structure. The method includes forming a buried P-type doped layer having low resistance under the P-wells and N-wells in which CMOS transistors are formed and forming a gap in a buried N-type doped layer formed in the P-wells, the is gap aligned under a contact to the P-well. The buried P-type doped layer and gap in the buried N-type doped layer allow a low resistance hole current path around parasitic bipolar transistors of the CMOS transistors.
Type:
Grant
Filed:
January 26, 2006
Date of Patent:
September 11, 2007
Assignee:
International Business Machines Corporation
Inventors:
Delbert R. Cecchi, Toshiharu Furukawa, Jack Allan Mandelman
Abstract: A semiconductor device suitable for applications in an electrostatic discharge (ESD) protection circuit, including a semiconductor substrate, a first well formed in the substrate, a second well formed in the substrate, and a first doped region formed in the second well, wherein the first well, the second well, and the first doped region collectively form a parasitic bipolar junction transistor (BJT), and wherein the first well is the collector of the BJT, the second well is the base of the BJT, and the first doped region is the emitter of the BJT.
Abstract: This invention discloses a semiconductor device with latch-up prevention mechanisms. According to one embodiment, it comprises a first N-type region, wherein one or more P-type metal-oxide-semiconductor (PMOS) devices are disposed therein, a second N-type region adjacent to the first N-type region, wherein one or more PMOS devices are also disposed therein, and a P-type region disposed between the first and second N-type regions, wherein one or more guard rings are disposed therein, so that the semiconductor device is more immune to latch-up.