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The development of DePFET (Depleted P-channel Field Effect Transistor) based sensors has gained significant momentum in recent years. Be it the PXD for the Belle II experiment, the DePFET based MIXS sensor aboard the planetary science mission BepiColombo, that will soon reach Mercury, the development of ultrafast real-time imagers for direct electron detection (EDET) at TEMs or the development of the Wide Field Imager (WFI) of the next generation X-ray telescope Athena. These sensors have been customized according to specific application requirements, including high frame rates, accurate position resolution, Fano-limited energy resolution, or maximized dynamic range. One of the development endeavors has resulted in the super- $\mathrm{g}_{\mathrm{q}}$ DePFET technology. This technology achieves significant improvements in signal-to-noise ratio by shrinking the internal gate while keeping the external gate untouched, effectively avoiding short channel effects. Charge generated in the fully depleted bulk is collected in this so called internal gate below the channel, whereby the conductivity of the transistor is modulated, and the number of signal electrons can be determined. Simulations predict a considerable increase in charge gain by a factor of three ($1.7 \mathrm{nA} / \mathrm{e}-)$ and white noise of less than one e- ENC, while limiting impact ionization near the drain end of the channel. These improvements make super- $\mathrm{g}_{\mathrm{q}}$ DePFETs potentially capable of reaching sub-electron noise levels with a single readout. Based on these findings a test production has been initiated and recently completed. Studies on energy resolution, gain improvement, noise as well as optimal operation parameters are carried out in a specially designed test setup that caters to the unique requirements of the DePFET sensors. It ensures reliable characterization under the conditions encountered in various conceivable applications. Moreover, the setup allows investigations down to cryogenic temperatures for the first time on matrix level.