Effect of carrier lifetime on forward-biased silicon Mach-Zehnder modulators

In semiconductor devices, diodes play a crucial role in directing current flow, and its operation is primarily categorized into forward bias and reverse bias. A diode is said to be forward-biased when its p-type region is connected to the positive terminal of a battery and its n-type region is linked to the negative terminal. This configuration reduces the potential barrier within the diode, allowing current to flow easily from the p to the n-type region.
The behavior of a diode in forward bias...

Carrier generation is the process by which electron-hole pairs (EHPs) are created within the semiconductor. In direct-bandgap semiconductors, such as gallium arsenide (GaAs), this occurs efficiently when energy absorption prompts valence electrons to leap into the conduction band, leaving behind holes.
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...

Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...

The operation of a p-n junction diode involves various biasing conditions, including forward bias, reverse bias, and equilibrium.
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...

Zener diodes are specialized semiconductor devices designed to operate in the reverse breakdown region, where they allow current to flow into the cathode, making it positive relative to the anode. This reverse operation distinguishes Zener diodes from conventional diodes and enables their use in various applications, most notably as voltage regulators. One of the defining characteristics of Zener diodes is their nearly vertical I-V (current-voltage) characteristic curve above a certain...

A diode is reverse-biased when the positive terminal of an external voltage source is connected to the n-type material and the negative terminal to the p-type material. This configuration opposes the natural direction of current flow through the diode, effectively increasing the width of the depletion region and the barrier potential. The reverse bias condition produces a minimal leakage current, primarily due to minority charge carriers. This leakage becomes significant when the reverse...