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Author

Leonard Forbes

Bio: Leonard Forbes is an academic researcher from Micron Technology. The author has contributed to research in topics: Gate oxide & Transistor. The author has an hindex of 96, co-authored 620 publications receiving 30052 citations.


Papers
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Patent
02 May 2002
TL;DR: In this paper, a LaAlO 3 gate dielectric is formed by atomic layer deposition employing a lanthanum sequence and an aluminum sequence, which is thermodynamically stable and has minimal reactions with a silicon substrate or other structures during processing.
Abstract: A dielectric film containing LaAlO 3 and method of fabricating a dielectric film contained LaAlO 3 produce a reliable gate dielectric having a thinner equivalent oxide thickness than attainable using SiO 2 . The LaAlO 3 gate dielectrics formed are thermodynamically stable such that these gate dielectrics will have minimal reactions with a silicon substrate or other structures during processing. A LaAlO 3 gate dielectric is formed by atomic layer deposition employing a lanthanum sequence and an aluminum sequence. A lanthanum sequence uses La(thd) 3 (thd=2,2,6,6-tetramethl-3,5-heptanedione) and ozone. An aluminum sequence uses either trimethylaluminium, Al(CH 3 ) 3 , or DMEAA, an adduct of alane (AlH 3 ) and dimethylehtylamine [N(CH 3 ) 2 (C 2 H 5 )], with distilled water vapor.

369 citations

Patent
24 Jun 2003
TL;DR: In this article, the dielectric can be formed as a nanolaminate of hafnium oxide and a lanthanide oxide, where the layer of the hafium oxide is adjacent and in contact with the surface of the lanthanides.
Abstract: Dielectric layers containing an atomic layer deposited hafnium oxide and an electron beam evaporated lanthanide oxide and a method of fabricating such a dielectric layer produce a reliable dielectric layer having an equivalent oxide thickness thinner than attainable using SiO 2 . Forming a layer of hafnium oxide by atomic layer deposition and forming a layer of a lanthanide oxide by electron beam evaporation, where the layer of hafnium oxide is adjacent and in contact with the layer of lanthanide, provides a dielectric layer with a relatively high dielectric constant as compared with silicon oxide. The dielectric can be formed as a nanolaminate of hafnium oxide and a lanthanide oxide.

304 citations

Patent
31 Aug 1998
TL;DR: An improved structure and method for increasing the operational bandwidth between different circuit devices, e.g. logic and memory chips, without requiring changes in current CMOS processing techniques is provided in this paper.
Abstract: An improved structure and method are provided for increasing the operational bandwidth between different circuit devices, e.g. logic and memory chips, without requiring changes in current CMOS processing techniques. The structure includes the use of a silicon interposer. The silicon interposer can consist of recycled rejected wafers from the front-end semiconductor processing. Micro-machined vias are formed through the silicon interposer. The micro-machined vias include electrical contacts which couple various integrated circuit devices located on the opposing surfaces of the silicon interposer.

287 citations

Patent
16 Jun 2000
TL;DR: In this article, a memory cell for a dynamic random access memory (DRAM) is constructed on semiconductor pillars on buried bit lines, and split gates are interposed between and shared between adjacent pillars for gating the transistors therein.
Abstract: An integrated circuit and fabrication method includes a memory cell for a dynamic random access memory (DRAM). Vertically oriented access transistors are formed on semiconductor pillars on buried bit lines. Buried first and second gates are provided for each access transistor on opposing sides of the pillars. Buried word lines extend in trenches orthogonal to the bit lines. The buried word lines interconnect ones of the first and second gates. In one embodiment, unitary gates are interposed and shared between adjacent pillars for gating the transistors therein. In another embodiment, separate split gates are interposed between and provided to the adjacent pillars for separately gating the transistors therein. In one embodiment, the memory cell has a surface area that is approximately 4 F 2 , where F is a minimum feature size. Bulk-semiconductor and semiconductor-on-insulator (SOI) embodiments are provided.

261 citations

Patent
29 Aug 2005
TL;DR: The use of ALD to form a nanolaminate dielectric of zirconium oxide (ZrO 2 ), hafnium oxide and tin oxide (SnO 2 ) is described in this article.
Abstract: The use of atomic layer deposition (ALD) to form a nanolaminate dielectric of zirconium oxide (ZrO 2 ), hafnium oxide (HfO 2 ) and tin oxide (SnO 2 ) acting as a single dielectric layer with a formula of Zr X Hf Y Sn 1-X-Y O 2 , and a method of fabricating such a dielectric layer is described that produces a reliable structure with a high dielectric constant (high k). The dielectric structure is formed by depositing zirconium oxide by atomic layer deposition onto a substrate surface using precursor chemicals, followed by depositing hafnium oxide onto the substrate using precursor chemicals, followed by depositing tin oxide onto the substrate using precursor chemicals, and repeating to form the thin laminate structure. Such a dielectric may be used as a gate insulator, a capacitor dielectric, or as a tunnel insulator in non-volatile memories, because the high dielectric constant (high k) provides the functionality of a much thinner silicon dioxide film.

257 citations


Cited by
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PatentDOI
06 Apr 2012-Science
TL;DR: In this article, the authors present stretchable and printable semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed, or otherwise deformed.
Abstract: The present invention provides stretchable, and optionally printable, semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Stretchable semiconductors and electronic circuits of the present invention preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention may be adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.

1,673 citations

Patent
01 Aug 2008
TL;DR: In this article, the oxide semiconductor film has at least a crystallized region in a channel region, which is defined as a region of interest (ROI) for a semiconductor device.
Abstract: An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

1,501 citations

PatentDOI
TL;DR: In this article, the authors present methods, systems and system components for transferring, assembling and integrating features and arrays of features having selected nanosized and/or microsized physical dimensions, shapes and spatial orientations.
Abstract: The present invention provides methods, systems and system components for transferring, assembling and integrating features and arrays of features having selected nanosized and/or microsized physical dimensions, shapes and spatial orientations. Methods of the present invention utilize principles of ‘soft adhesion’ to guide the transfer, assembly and/or integration of features, such as printable semiconductor elements or other components of electronic devices. Methods of the present invention are useful for transferring features from a donor substrate to the transfer surface of an elastomeric transfer device and, optionally, from the transfer surface of an elastomeric transfer device to the receiving surface of a receiving substrate. The present methods and systems provide highly efficient, registered transfer of features and arrays of features, such as printable semiconductor element, in a concerted manner that maintains the relative spatial orientations of transferred features.

1,305 citations

Patent
06 Dec 2002
TL;DR: In this article, a very high density field programmable memory (FPM) is described. And the array is formed vertically above a substrate using several layers, each layer of which includes vertically fabricated memory cells.
Abstract: A very high density field programmable memory is disclosed. An array is formed vertically above a substrate using several layers, each layer of which includes vertically fabricated memory cells. The cell in an N level array may be formed with N+1 masking steps plus masking steps needed for contacts. Maximum use of self alignment techniques minimizes photolithographic limitations. In one embodiment the peripheral circuits are formed in a silicon substrate and an N level array is fabricated above the substrate.

1,212 citations

Patent
17 Mar 2009
TL;DR: The 3Dimensional Structure (3DS) Memory (100) as mentioned in this paper is a three-dimensional structure (3D) memory that allows physical separation of the memory circuits and the control logic circuit onto different layers such that each layer may be separately optimized.
Abstract: A Three Dimensional Structure (3DS) Memory (100) allows for physical separation of the memory circuits (103) and the control logic circuit (101) onto different layers (103) such that each layer may be separately optimized. One control logic circuit (101) suffices for several memory circuits (103), reducing cost. Fabrication of 3DS memory (100) involves thinning of the memory circuit (103) to less than 50 microns in thickness and bonding the circuit to a circuit stack while still in wafer substrate form. Fine-grain high density inter-layer vertical bus connections (105) are used. The 3DS memory (100) manufacturing method enables several performance and physical size efficiencies, and is implemented with established semiconductor processing techniques.

1,212 citations