Described herein are methods and apparatuses for packaging an ultrasound-on-a-chip. An ultrasound-on-a-chip may be coupled to a redistribution layer and to an interposer layer. Encapsulation may encapsulate the ultrasound-on-a-chip device and first metal pillars may extend through the encapsulation and electrically couple to the redistribution layer. Second metal pillars may extend through the interposer layer. The interposer layer may include aluminum nitride. The first metal pillars may be electrically coupled to the second metal pillars. A printed circuit board may be coupled to the interposer layer.