PNP lateral bipolar electronic device and corresponding manufacturing process

A method of manufacturing a lateral PNP bipolar device, said method comprising:

• doping a semiconductor substrate with P-type dopant;
• depositing an N-type first buried layer over the semiconductor substrate;
• depositing an N-type second layer, over the first buried layer, to form an active area;
• depositing a patterned oxide layer over the second layer to define a base channel region;
• selectively doping the active area to form a collector and an emitter regions separated by the base channel region;
• forming a opening over the oxide layer;
• depositing a nitride layer within and adhering to sidewalls of the opening;
• and
• forming sidewall spacers over the nitride layer.

A method to form a lateral PNP bipolar device, the method comprising:

• forming an active area from an N-type substance;
• forming a base channel region having a width by placing a layer of patterned oxide contiguous with portions of the active area;
• forming a conductive layer contiguous with portions of the patterned oxide;
• and
• forming an opening in the conductive layer to expose portions of the patterned oxide, the width of the base channel region determined by dimensions of the opening and remaining portions of the conductive layer contiguous with portions of the patterned oxide.

A method of making a lateral PNP bipolar device, the method comprising:

• forming a semiconductor substrate doped with P type impurities;
• forming a first buried layer to be overlying a portion of the semiconductor substrate;
• doping the first buried layer with N type impurities to form a base region;
• forming a second layer to have a first surface adjacent a portion of the first layer, to have an N type conductivity, and to represent an active area;
• forming an oxide layer to be a contiguous piece and to have a first surface adjacent a portion of a second surface of the second layer, the second surface of the second layer being opposite the first surface of the second layer;
• forming a collector region adjacent a portion of the second layer, the collector region adjacent a first end portion of the oxide layer;
• forming an emitter region adjacent a portion of the second layer, the emitter region adjacent a second end portion of the oxide layer, the second end portion of the oxide layer opposite the first end portion of the oxide layer;
• forming an opening through a polysilicon layer, a first surface of the polysilicon layer adjacent a second surface of the oxide layer, the second surface of the oxide layer opposite the first surface of the oxide layer, the opening having a first inner surface defined by a first edge of the polysilicon layer, the opening having a second inner surface defined by a second edge of the polysilicon layer, the opening being bounded along a plane by an opening portion of the second surface of the oxide layer;
• forming a first portion of a nitride layer adjacent the first edge of the polysilicon layer, the first portion of the nitride layer adjacent a first part of the opening portion of the second surface of the oxide layer;
• and
• forming a second portion of a nitride layer adjacent the second edge of the polysilicon layer, the second portion of the nitride layer adjacent a second part of the opening portion of the second surface of the oxide layer.