Did You Know...
...that several people are credited with the invention of the flush toilet? Most people have heard of Thomas Crapper (1837-1910), the sanitary engineer who invented the valve-and-siphon arrangement that made the modern toilet possible. Another claimant to "the throne" was British inventor Alexander Cumming who patented a toilet in 1775. Then there's a nameless Minoan (a native of ancient Crete) who lived 4,000 years ago who supposedly was ahead of his time and created the first flush toilet!
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 7435987 | Forming a type I heterostructure in a group IV semiconductor In one embodiment, the present invention includes a method for forming a transistor that includes forming a first buffer layer of silicon germanium tin (SiGe(Sn)) on a silicon (Si) substrate, forming a barrier layer on the first buffer layer, the barrier layer compr... | 10/14/2008 |
| 7358581 | Quantum dot based pressure switch A semiconductor heterostructure based pressure switch comprising: first and second small bandgap material regions separated by a larger bandgap material region; a third small bandgap material region within the region of larger bandgap material, the third material re... | 04/15/2008 |
| 6593589 | Semiconductor nitride structures The present invention provides a unipolar semiconductor structure comprising: at least one active layer comprising at least one group III-nitride; and at two barrier layers disposed on either side of the active layer, each of the two barrier layers compri... | 07/15/2003 |
| 6459120 | Semiconductor device and manufacturing method of the same A regular tetrahedral groove is formed in a wafer, and a memory unit is formed, which includes a channel layer as a first semiconductor layer to serve as a channel, a three-layer structure floating layer as a second semiconductor layer to serve as a float... | 10/01/2002 |
| 6376858 | Resonant tunneling diode with adjusted effective masses A tunnel diode has a quantum well having at least one layer of semiconductor material. The tunnel diode also has a pair of injection layers on either side of the quantum well. The injection layers comprise a collector layer and an emitter layer. A barrier... | 04/23/2002 |
| 5922621 | Quantum semiconductor device and a fabrication process thereof A method for fabricating a quantum semiconductor device includes the steps of forming an etch pit of a triangular pyramid on a {111}A-oriented principal surface of a substrate having zinc blende structure by a dry etching process, and depositing semicondu... | 07/13/1999 |
| 5679179 | Method of forming GaAs/AlGaAs hetero-structure and GaAs/AlGaAs hetero-structure obtained by the method A method of forming GaAs/AlGaAs hetero-structure. The method includes the steps of preparing a GaAs substrate having a (411)A-oriented surface and setting the GaAs substrate inside a growth container with the (411)A surface being disposed as a surface to ... | 10/21/1997 |
| 5656821 | Quantum semiconductor device with triangular etch pit A semiconductor device is provided, including a semiconductor substrate of zinc blend structure, defined by a principal surface substantially coinciding to a {111}A-oriented crystal surface; an etch pit of the shape of a triangular pyramid, formed on the ... | 08/12/1997 |
| 5521404 | Group III-V interdiffusion prevented hetero-junction semiconductor device A high electron mobility transistor type group III-V compound semiconductor device includes a substrate of a group III-V compound semiconductor, an electron transfer layer of a group III-V compound semiconductor formed on the substrate, an impurity doped ... | 05/28/1996 |
| 5311009 | Quantum well device for producing localized electron states for detectors and modulators In accordance with the invention, a quantum well device provides localized states for electrons having an energy E greater than the barrier height of the constituent quantum wells. The device comprises a confinement quantum well of width Lw equ... | 05/10/1994 |
| 5296721 | Strained interband resonant tunneling negative resistance diode A double barrier tunnel diode (10) has a quantum well (12), a pair of electron injection layers (16) on either side of the quantum well (12), and a barrier layer (14) between each of the electron injection layers (16) and the quantum well (12), in a strai... | 03/22/1994 |
| 5160982 | Phonon suppression in quantum wells An enhanced mobility semiconductor comprising a host quantum well having at least two charge carrier barrier layers of a wide bandgap material, each of the two charge carrier barrier layers being separated by a conducting region containing charge carriers... | 11/03/1992 |
| 5132746 | Biaxial-stress barrier shifts in pseudomorphic tunnel devices Resonant tunneling devices having improved peak-to-valley current ratios are disclosed. The resonant tunneling device comprises a quantum well layer surrounded by first and second barrier layers, the first and second barrier layers being comprised of an i... | 07/21/1992 |
| 5119151 | Quasi-one-dimensional channel field effect transistor having gate electrode with stripes A quasi-one-dimensional channel field effect transistor is suitable for an ultra high speed operation due to reduction in scattering, and comprises a quantum well structure for producing a two dimensional carrier gas, a etching stopper layer formed on the... | 06/02/1992 |
| 5081511 | Heterojunction field effect transistor with monolayers in channel region A heterojunction field effect transistor (HFET) having a source, drain, and channel, wherein the channel comprises a quantum well and at least one mono-atomic well or barrier layer is provided. The mono-atomic well or barrier layer has a different bandgap... | 01/14/1992 |
| 5049951 | Superlattice field effect transistor with monolayer confinement A heterojunction field effect transistor (HFET) having a source, drain, and channel, wherein the channel is a top layer of a superlattice buffer, eliminating the need for a thick buffer layer. The superlattice buffer comprises alternating barrier and quan... | 09/17/1991 |
| 4987458 | Semiconductor biased superlattice tunable interference filter/emitter Continuously tunable, biased, semiconductor superlattice electron interference filter/emitter which can serve, for example, as a hot electron emitter in a ballistic transistor, provides energy selectivity for substantially ballistic electron wave propagat... | 01/22/1991 |
| 4970563 | Semiconductor quantum well electron and hole waveguides Semiconductor, quantum well, electron and hole slab waveguides include a substrate semiconductor layer, a film semiconductor layer, and a cover semiconductor layer, wherein the semiconductor layers provide substantially ballistic transport for electrons a... | 11/13/1990 |
