High power switch with improved avalanche breakdown voltage using well blocking

A semiconductor switch comprising:

• a P substrate having a top surface over a bottom surface that is opposite the top surface;
• a deep N-Well over the P substrate;
• an inner P-Well over the deep N-Well;
• a gate over the top surface and over the inner P-Well;
• a source over the inner P-Well having a contact coupled to the gate through the inner P-Well;
• a drain over the inner P-Well having a contact coupled to the gate through the inner P-Well;
• a body electrode over the inner P-Well having a contact coupled to the gate through the inner P-Well;
• an inner moat formed of the P substrate outside of and over the deep N-Well, the inner moat surrounding the gate, the source, the drain, the body electrode, and the inner P-Well;
• an N-type contact well surrounding the inner P-Well and the inner moat, wherein the gate, the source, the drain, the body electrode, and the inner moat are over the deep N-Well;
• an outer moat formed of the P substrate outside the deep N-Well over the substrate;
• and
• a P-type floating well inside of the outer moat and outside of the N-type contact well over the P substrate to divide the outer moat into the outer moat and a middle moat.

A radio transceiver comprising:

• a power amplifier configured to amplify a modulated data signal;
• an antenna pin coupled to the power amplifier and configured to couple the modulated data signal to an aerial;
• a low noise amplifier coupled to the antenna pin configured for reception of a wireless data signal from the aerial through the antenna pin;
• a transmit/receive switch between the power amplifier and the antenna pin configured to connect and disconnect the power amplifier and the antenna pin, the transmit/receive switch comprising:
• a substrate of a first type having a top surface over a bottom surface that is opposite the top surface;
• a deep well of a second type over the substrate;
• an inner well of the first type over the deep well;
• a gate over the top surface and over the inner well;
• a source over the inner well having a contact of a second type coupled to the gate through the inner well;
• a drain over the inner well having a contact of the second type coupled to the gate through the inner well;
• a body electrode over the inner well having a contact of the first type coupled to the gate through the inner well;
• an inner moat outside of the inner well and over the deep well surrounding the gate, the source, the drain, and the body electrode;
• a deep well contact outside of the inner moat and over the deep well having a contact of the second type and a contact well of the second type, the contact well surrounding the inner well, wherein the gate, the source, the drain, the body electrode, and the inner moat are over the deep well;
• and
• an outer moat outside the deep well over the substrate and surrounding the contact well.