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How does a p-n-p transistor differ from an n-p-n transistor?

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NMOS transistorNegative-channel metal-oxide semiconductors (NMOS) employ a positive secondary voltage to switch a shallow layer of p-type semiconductor material below the gate into n-type. For positive-channel metal-oxide semiconductors (PMOS), all these polarities are reversed. NMOS transistors are more expensive, but faster, than PMOS transistors. — transistor NMOS transistor
Negative-channel metal-oxide semiconductors (NMOS) employ a positive secondary voltage to switch a shallow layer of p-type semiconductor material below the gate into n-type. For positive-channel metal-oxide semiconductors (PMOS), all these polarities are reversed. NMOS transistors are more expensive, but faster, than PMOS transistors.

Bipolar transistors are categorized into two complementary types: p-n-p and n-p-n transistors. Their primary difference lies in the arrangement of their semiconductor layers and the resulting polarity of their operation.1

Structure: A p-n-p transistor consists of an n-type base region sandwiched between two p-type regions (the emitter and collector). Conversely, an n-p-n transistor is formed by interchanging these materials, placing a p-type base between two n-type regions.1
Operation: Because the material types are reversed, the current flow and voltage polarities in an n-p-n transistor are the opposite of those in a p-n-p transistor.1
Charge Carriers: In a p-n-p transistor, the majority carriers injected from the emitter into the base are holes. In an n-p-n transistor, the majority carriers are electrons.1

Both types function as bipolar devices, meaning they rely on the movement of both electrons and holes to facilitate current conduction and signal amplification within electronic circuits.1