Sticky ads are ads which are shown in a fixed spot. Even when the website is scrolled down or to the top the ad is not moving and keeps focused at this selected location.
Some ad publishers are offering the use of these ads. Even AdSense is permitting this if your website is a high traffic site. Please note, that usually you are not allowed to use sticky AdSense ads.
At the time of writing this doc WP QUADS is not offering native support for sticky ads but there is a easy to use and very small free plugin which creates this type of ad format to any WordPress website.
Download and activate the plugin and paste your Google AdSense code into the Sticky Ad Bar Plugin.