Lateral Semiconductor Power Devices

A lateral power semiconductor device, comprising:

• a first-conductivity-type source region;
• a second-conductivity-type body region, and a gate electrode which is capacitively coupled to a portion of the body region;
• a first-conductivity-type drain region;
• a first-conductivity-type drift region, which is laterally interposed between the drain region and the body region in an electrical relation such that, when the gate electrode has a voltage which inverts part of the body region to form a channel therein, majority carriers can flow from the source region, through the channel, through the drift region, to the drain region;
• wherein the source, body, drift, and drain regions are all located within a mass of second-conductivity-type semiconductor material;
• second-conductivity-type charge balancing regions which laterally flank the drift region, and which are laterally flanked by insulating trenches;
• and
• first-conductivity-type bottom regions below the trenches;
• wherein, when reverse bias is present between the source and drain regions, the space charge of depleted portions of the second-conductivity-type charge balancing regions will at least partially balance the space charge of depleted portions of the drift region, and the space charge of depleted portions of the first-conductivity-type bottom regions will at least partially balance the space charge of depleted portions of the second-conductivity-type semiconductor mass.

A lateral power semiconductor device, comprising:

• a first-conductivity-type source region;
• a second-conductivity-type body region, and a gate electrode which is capacitively coupled to a portion of the body region;
• a first-conductivity-type drain region;
• a first-conductivity-type drift region, which is laterally interposed between the drain region and the body region in an electrical relation such that, when the gate electrode has a voltage which inverts part of the body region to form a channel therein, majority carriers can flow from the source region, through the channel, laterally through the drift region, to the drain region;
• wherein the source, body, drift, and drain regions are all located within a mass of second-conductivity-type semiconductor material;
• second-conductivity-type charge balancing regions which laterally flank the drift region, and which are laterally flanked by insulating trenches;
• and
• a second-conductivity-type upper region which overlies the drift region;
• wherein, when reverse bias is present between the source and drain regions, the space charge of depleted portions of the second-conductivity-type charge balancing regions and of the upper region will at least partially balance the space charge of depleted portions of the drift region.