Preheat oven to 350 degrees. Lightly spray a 7-inch or 8-inch springform pan with baking spray. Wrap the outside with foil, crimp around the top edges of the pan.
In a large ziploc bag or a food processor, crush the graham crackers until fine. Add butter, brown sugar and salt, mix to combine. Press into the bottom and up the sides of the prepared springform pan. Place in the oven and bake for 8 minutes. Remove and allow to cool while preparing the filling.
To prepare the filling, in the bowl of a stand mixer or a large mixing bowl with a handheld mixer, add the sugar, cornstarch and salt. Mix on low to combine. Add vanilla extract and Greek yogurt, mix on medium until creamy. With mixing speed on low, add cream cheese. Turn mixing speed up and beat until smooth, about 2 minutes. Add eggs and mix until combined, about 1 minute.
Pour the filling into the baked crust. Tap on the counter 3-4 times to remove air bubbles. Cover the top with foil, pressing tightly to seal it in.
Pour 1 1/4 cups of water into the Instant Pot. If using a 7-inch springform, place the steamer rack in the bottom. If using an 8-inch springform you'll need to place something in the bottom of the insert like a metal mason jar sealing ring (it will raise it up enough). Center the springform pan on a foil sling* and lower it into the Instant Pot and onto the rack or ring. Fold the foil sling on top of the cheesecake.
Close and lock the lid. Select MANUAL (and make sure it's on high pressure) for 45 minutes. When it beeps, either turn it off or let it switch to KEEP WARM. Allow the pressure to release naturally (do not turn the presure release to venting). This takes about 18-20 minutes.
Remove the lid and carefully lift the cheesecake from the pot. Remove the foil on top and peel of the foil from around the pan. Allow to cool at room temperature for 30 minutes before transferring to the refrigerator to cool uncovered for at least 2 hours. For a thicker, firmer cheesecake, cool 4+ hours (placing plastic wrap over top at the 2 hour mark).