Place an oven rack in top position in oven, close to broiler. Place a second rack in position immediately below. Preheat broiler to high. Line a rimmed baking sheet with heavy-duty aluminum foil. Combine potato chips, bread crumbs and dill in a small bowl.
Place salmon fillets on baking sheet. Brush with oil and sprinkle with salt and pepper. Broil on upper rack until surface begins to brown, 7 to 9 minutes.
Remove from oven and spread mustard over fish. Spoon potato-chip mixture onto fillets; press it into fish with back of spoon. Return pan to lower oven rack and broil until crust is golden, 30 seconds to 1 minute. Serve immediately.