This is how I get the perfect sear. It is unbelievably fast and wonderful.
First, wash the scallops off and then dry them on a paper towel. Then, lightly salt and pepper both sides of the scallops.
Then make sure that you are using a nonstick metal pan so you can see when your butter starts to get brown. Throw in around half a tablespoon or a tablespoon of unsalted butter and watch it until it starts to turn golden brown. This means the pan is at the right temperature for the scallops. Place the scallops in far enough apart so that they do not affect each other (if they are too close, they could actually steam each other, preventing nice carmelization). After about 1-2 minutes (depending on size, leave in longer), using tongs, flip your scallops over. The butter should be sizzling. Do not, under any circumstances, move your scallops from their place on the pan until ready to flip. Once you flip over, take pan off heat and cook second side for thirty seconds until done. Voila!