Chip-scale monolithic optoelectronic voltage boost conversion

TL;DR

This paper introduces a chip-scale, monolithic optoelectronic voltage boost converter that achieves high gain and broad voltage scaling by integrating LEDs and PV cells on a single InGaAsP chip, overcoming limitations of traditional methods.

Contribution

The work presents a novel monolithic, integrated optoelectronic platform for voltage conversion that eliminates Stokes losses and enhances performance over discrete component solutions.

Findings

Achieved a 3.8x voltage boost gain experimentally.

Demonstrated high current density and reduced non-radiative losses in simulations.

Validated the platform's effectiveness with an 8x8 mm$^2$ InGaAs-on-InP chip.

Abstract

Voltage conversion is a fundamental electronic process critical to engineered systems across a wide spectrum of applications and spanning many orders of magnitude in scale. Conventional approaches like transformers and charge pumps perform well in specific contexts but face fundamental limitations to miniaturization, electromagnetic interference, and voltage range. Here we present a chip-scale, fully integrated monolithic, non-switching optoelectronic voltage conversion platform capable of high gain, bootstrap-free boost-mode operation across several orders of magnitude in power density and voltage scale. Using the bidirectional coupling between LEDs and PV cells with identical active layer materials, our chip-scale, single-die strategy eliminates Stokes losses while improving key parameters like physical footprint, series resistance, and photon leakage by orders of magnitude over implementations using multiple packaged, discrete components. Moreover, by exploiting the large \'etendue of NIR-transparent semi-insulating InP substrates and the atomically smooth, void-free interface of lattice-matched epitaxial growth, simulations indicate that our InGaAsP architecture's photon transport simultaneously provides a > 60x increase in current density and > 50x reduction in non-radiative recombination losses compared with a multiple-die solution while simultaneously reducing fabrication complexity and improving mechanical robustness. We experimentally demonstrate a boost gain of 3.8x in an 8x8 mm$^2$ InGaAs-on-InP chip while validating key aspects of the voltage conversion platform.