Multiwall carbon nanotube (MWCNT) tunnel diode arrays are promising for high frequency optoelectronic applications, including rectennas for infrared and optical energy harvesting. Challenges to MWCNT diode performance have been air stability, high resistance, and lack of asymmetry hindering rectification. Recent research has systematically addressed these issues and demonstrated improvements in MWCNT diodes by incorporating two insulators with dissimilar electron affinities to achieve excellent asymmetry (>20) with air stable and low resistance metal contacts. We expand on that result by characterizing the performance of MWCNT tunnel diodes with a variety of multi-insulator configurations through repeated layers of Al₂O₃ and ZrO₂. We demonstrate the first quad-insulator (Al₂O₃-ZrO₂-Al₂O₃-ZrO₂) MWCNT tunnel diode, providing outstanding asymmetry (>300) and low turn-on voltage (0.25 V) while using air stable materials. Our results reveal multi-insulator geometry as a critical factor in designing high performance MWCNT diodes for solar and infrared energy conversion and reveals a promising direction for future research.