International Rectifier Corporation

Infineon Technologies Americas Corp.

Chiu Ng

Richard Francis

Yi Tang

Florin Udrea

Gianluca Camuso

Rajeev Krishna Vytla

Alice Pei-Shan Hsieh

Niraj Ranjan

Ranadeep Dutta

Hamilton Lu

Canhua Li

Davide Chiola

Peter N Wood

Yuan-Heng Chao

Fabrizio Ruo Redda

There are disclosed herein various implementations of a bipolar semiconductor device with multi-trench enhancement regions. Such a bipolar semiconductor device includes a drift region having a first conductivity type situated over an anode layer having an opposite, second conductivity type. The device also includes a first control trench extending through an inversion region having the second conductivity type, and further extending into the drift region, the first control trench being adjacent to cathode diffusions. In addition, the device includes first and second depletion trenches, each having a depletion electrode, the first depletion trench being situated between the second depletion trench and the first control trench. An enhancement region having the first conductivity type is localized in the drift region and extends from the first control trench to the first second depletion trench and further from the first depletion trench to the second depletion trench.

Bipolar semiconductor device with multi-trench enhancement regions

A semiconductor device includes a drift region of a first conductivity type, an anode region of a second conductivity type situated below the drift region, an inversion region of the second conductivity type situated above the drift region, an enhancement region of the first conductivity type situated between the drift region and the inversion region, first and second control trenches extending through the inversion region and the enhancement region into the drift region, each control trench being bordered by a cathode diffusion region of the first conductivity type, and a superjunction structure situated in the drift region between the first and the second control trenches so that the superjunction structure does not extend under either the first or the second control trench. The superjunction structure is separated from the inversion region by the enhancement region and includes alternating regions of the first and the second conductivity types.

Semiconductor device having a superjunction structure

There are disclosed herein various implementations of a bipolar semiconductor device with sub-cathode enhancement regions. Such a bipolar semiconductor device includes a drift region having a first conductivity type situated over an anode layer having a second conductivity type opposite the first conductivity type. The bipolar semiconductor device also includes first and second depletion trenches, each having a depletion electrode. In addition, the bipolar semiconductor device includes a first control trench situated between the first and second depletion trenches, the first control trench extending into the drift region and being adjacent to cathode diffusions. An enhancement region having the first conductivity type is localized in the drift region between the first control trench and one or both of the first and second depletion trenches. In one implementation, the bipolar semiconductor device may be an insulated-gate bipolar transistor (IGBT).

Bipolar semiconductor device with sub-cathode enhancement regions

There are disclosed herein various implementations of an insulated-gate bipolar transistor (IGBT) with buried depletion electrode. Such an IGBT may include a collector at a bottom surface of a semiconductor substrate, a drift region having a first conductivity type situated over the collector, and a base layer having a second conductivity type opposite the first conductivity type situated over the drift region. The IGBT also includes a plurality of deep insulated trenches with a buried depletion electrode and at least one gate electrode disposed therein. In addition, the IGBT includes an active cell including an emitter adjacent the gate electrode, and an implant zone, situated between adjacent deep insulated trenches. The implant zone is formed below the base layer and has the first conductivity type. In one implementation, the IGBT may also include a dummy cell neighboring the active cell.

IGBT having deep gate trench

There are disclosed herein various implementations of a bipolar semiconductor device having a deep charge-balanced structure. Such a device includes a drift region having a first conductivity type situated over an anode layer having a second conductivity type. The device also includes a control trench extending through an inversion region having the second conductivity type into the drift region, and bordered by a cathode diffusion having the first conductivity type. In addition, the device includes a deep sub-trench structure situated under the control trench. The deep sub-trench structure includes one or more first conductivity regions having the first conductivity type and one or more second conductivity region having the second conductivity type, the one or more first conductivity regions and the one or more second conductivity regions configured to substantially charge-balance the deep sub-trench structure. In one implementation, the bipolar semiconductor device is an insulated-gate bipolar transistor (IGBT).

Bipolar semiconductor device having a deep charge-balanced structure

There are disclosed herein various implementations of an insulated-gate bipolar transistor (IGBT) having a deep superjunction structure. Such an IGBT includes a drift region having a first conductivity type situated over a collector having a second conductivity type. The IGBT also includes a gate trench extending through a base having the second conductivity type into the drift region. In addition, the IGBT includes a deep superjunction structure situated under the gate trench. The deep superjunction structure includes one or more first conductivity regions having the first conductivity type and two or more second conductivity region having the second conductivity type, the one or more first conductivity regions and the two or more second conductivity regions configured to substantially charge-balance the deep superjunction structure.

IGBT having a deep superjunction structure

There are disclosed herein various implementations of a bipolar semiconductor device having a charge-balanced inter-trench structure. Such a device includes a drift region having a first conductivity type situated over an anode layer having a second conductivity type. The device also includes first and second control trenches extending through an inversion region having the second conductivity type into the drift region, each of the first and second control trenches being bordered by a cathode diffusion having the first conductivity type. In addition, the device includes an inter-trench structure situated in the drift region between the first and second control trenches. The inter-trench structure includes one or more first conductivity regions having the first conductivity type and one or more second conductivity region having the second conductivity type, the one or more first conductivity regions and the one or more second conductivity regions configured to substantially charge-balance the inter-trench structure.

Bipolar semiconductor device having a charge-balanced inter-trench structure

There are disclosed herein implementations of an insulated-gate bipolar transistor (IGBT) having an inter-trench superjunction structure. Such an IGBT includes a drift region having a first conductivity type situated over a collector having a second conductivity type. The IGBT also includes first and second gate trenches extending through a base having the second conductivity type into the drift region, the first and second gate trenches each being bordered by an emitter diffusion having the first conductivity type. In addition, the IGBT includes an inter-trench superjunction structure situated in the drift region between the first and second gate trenches. The inter-trench superjunction structure includes one or more first conductivity regions having the first conductivity type and two or more second conductivity region having the second conductivity type, the one or more first conductivity regions and the two or more second conductivity regions configured to substantially charge-balance the inter-trench superjunction structure.

IGBT having an inter-trench superjunction structure

There are disclosed herein various implementations of an insulated gate bipolar transistor (IGBT) with buried emitter electrodes. Such an IGBT may include a collector at a bottom surface of a semiconductor substrate, a drift region having a first conductivity type situated over the collector, and a base layer having a second conductivity type opposite the first conductivity type situated over the drift region. In addition, such an IGBT may include deep insulated trenches extending from a semiconductor surface above the base layer, into the drift region, each of the deep insulated trenches having a buried emitter electrode disposed therein. The IGBT may further include an active cell including an emitter, a gate trench with a gate electrode disposed therein, and an implant zone situated, between adjacent deep insulated trenches. The implant zone is formed below the base layer and has the first conductivity type.

IGBT with buried emitter electrode

Deep gate trench IGBT

A semiconductor device is formed in a thin float zone wafer. Junctions are diffused into the top surface of the wafer and the wafer is then reduced in thickness by removal of material from its bottom surface. A weak collector is then formed in the bottom surface by diffusion of boron (for a P type collector). The weak collector is then formed or activated only over spaced or intermittent areas. This is done by implant of the collector impurity through a screening mask; or by activating only intermittent areas by a laser beam anneal in which the beam is directed to anneal only preselected areas. The resulting device has an effective very low implant dose, producing a reduced switching energy and increased switching speed, as compared to prior art weak collector/anodes and life time killing technologies.

Semiconductor device having increased switching speed

A trench type IGBT as disclosed herein includes a plurality of channel regions having one threshold voltage for the normal operation of the device and a plurality of channel regions having a threshold voltage higher than the threshold voltage for the normal operation of the device.

Variable threshold trench IGBT with offset emitter contacts

A very low Vnon punch through trench IGBT built-in non-epitaxial float zone silicon has a depletion stop layer structure added to its bottom surface.

Trench IGBT with depletion stop layer

An IGBT for controlling the application of power to a plasma display panel has an increased current conduction capability and a reduced conduction loss at the expense of a reduced safe operating area. For a device with a 300 volt breakdown voltage rating, the die has a substrate resistivity less than 10 m ohm cm; a buffer layer thickness of about 8 &#x3bc;m resistivity in the range of 0.05 to 0.10 ohm cm, and an epi layer for receiving junction patterns and trenches, which has a thickness of from 31 to 37 &#x3bc;m and resistivity in te range of 14 to 18 ohm cm.

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El Segundo, CA, United States of America

Chiu Ng