After forming a laterally contacting pair of a semiconductor fin and a conductive strap structure having a base portion vertically contacting a deep trench capacitor embedded in a substrate and a fin portion laterally contacting the semiconductor fin, conducting spikes that are formed on the sidewalls of the deep trench are removed or pushed deeper into the deep trench. Subsequently, a dielectric cap that inhibits epitaxial growth of a semiconductor material thereon is formed over at least a portion of the base portion of the conductive strap structure. The dielectric cap can be formed either over an entirety of the base portion having a stepped structure or on a distal portion of the base portion.

A memory device includes: a semiconductor column extending vertically on a substrate and including a source region of a first conductivity type, an intrinsic region, and a drain region of a second conductivity type; a first gate electrode disposed adjacent to the drain region to cover the intrinsic region; a second gate electrode spaced apart from the first gate electrode and disposed adjacent to the source region to cover the intrinsic region; a first gate insulating layer disposed between the first gate electrode and the intrinsic region; and a second gate insulating layer disposed between the second gate electrode and the intrinsic region.

After forming a laterally contacting pair of a semiconductor fin and a conductive strap structure having a base portion vertically contacting a deep trench capacitor embedded in a substrate and a fin portion laterally contacting the semiconductor fin, conducting spikes that are formed on the sidewalls of the deep trench are removed or pushed deeper into the deep trench. Subsequently, a dielectric cap that inhibits epitaxial growth of a semiconductor material thereon is formed over at least a portion of the base portion of the conductive strap structure. The dielectric cap can be formed either over an entirety of the base portion having a stepped structure or on a distal portion of the base portion.

Methods and systems for reducing electrical disturb effects between thyristor memory cells in a memory array are provided. Electrical disturb effects between cells are reduced by using a material having a reduced minority carrier lifetime as a cathode line that is embedded within the array. Disturb effects are also reduced by forming a potential well within a cathode line, or a one-sided potential barrier in a cathode line.

Apparatus and methods for reducing minority carriers in a memory array are described herein. Minority carriers diffuse between ON cells and OFF cells, causing disturbances during write operation as well as reducing the retention lifetime of the cells. Minority Carrier Lifetime Killer (MCLK) region architectures are described for vertical thyristor memory arrays with insulation trenches. These MCLK regions encourage recombination of minority carriers. In particular, MCLK regions formed by conductors embedded along the cathode line of a thyristor array, as well as dopant MCLK regions are described, as well as methods for manufacturing thyristor memory cells with MCLK regions.

Methods and systems for reducing electrical disturb effects between thyristor memory cells in a memory array are provided. Electrical disturb effects between cells are reduced by using a material having a reduced minority carrier lifetime as a cathode line that is embedded within the array. Disturb effects are also reduced by forming a potential well within a cathode line, or a one-sided potential barrier in a cathode line.

Some embodiments include thyristors having first and second electrode regions, first and second base regions, and material having a bandgap of at least 1.2 eV in at least one of the regions. The first base region is between the first electrode region and the second base region, and the second base region is between the second electrode region and the first base region. The first base region interfaces with the first electrode region at a first junction, and interfaces with the second base region at a second junction. The second base region interfaces with the second electrode region at a third junction. A gate is along the first base region, and in some embodiments does not overlap either of the first and second junctions. Some embodiments include methods of programming thyristors, and some embodiments include methods of forming thyristors.

In a rectifier circuit, by using a transistor whose off-state current is small as a so-called diode-connected MOS transistor included in the rectifier circuit, breakdown which is caused when a reverse bias is applied is prevented. Thus, an object is to provide a rectifier circuit whose reliability is increased and rectification efficiency is improved. A gate and a drain of a transistor are both connected to a terminal of the rectifier circuit to which an AC signal is input. In the transistor, an oxide semiconductor is used for a channel formation region and the off-state current at room temperature is less than or equal to 10.sup.20 A/m, which is equal to 10 zA/m (z: zepto), when the source-drain voltage is 3.1 V.

In one embodiment, a Light Emitting Diode (LED) driving device for driving a plurality of LEDs has a switching matrix utilizing a plurality of one of a turn off thyristors or turn off triacs coupled to the plurality of LEDs. A controller is coupled to the switching matrix responsive to a voltage of a rectified AC halfwave, wherein combinations of the plurality of LEDs are altered to ensure a maximum operating voltage of the plurality of LEDs is not exceeded. A current limiting device is coupled to the combinations of the plurality of LED to regulate current. In a second embodiment an offline charge pump utilizes a switching matrix to recombine capacitors in accordance with the voltage on the AC half wave and then in accordance with a desired output voltage to feed a load, such that said recombinations occur at a frequency much higher than the frequency of the AC rectified half wave such that charge is pumped from the input at one voltage to the output at another voltage through the AC halfwave while providing a constant output voltage to the load.

A semiconductor device is provided. The semiconductor device includes an avalanche photodiode unit and a thyristor unit. The avalanche photodiode unit is configured to receive incident light to generate a trigger current and comprises a wide band-gap semiconductor. The thyristor unit is configured to be activated by the trigger current to an electrically conductive state. A semiconductor device and a method for making a semiconductor device are also presented.