Scanning acoustic micro imaging method and apparatus for non-rectangular bounded files

An apparatus for use in acoustic micro-imaging, said apparatus comprising:

• a transducer that is adapted to be coupled to a microelectronic sample or to a sealed package via a coupling medium;
• a controller that is operatively coupled to said transducer, said controller being adapted to cause said transducer to interrogate a space on a surface or within a volume of the microelectronic sample or the sealed package by emitting a pulse of acoustic energy toward each one of a plurality of points located within said space, and by receiving a reflection signal corresponding to each one of said emitted pulses;
• wherein said controller is further adapted to cause relative movement between said transducer and said microelectronic sample or the sealed package so that, when said space is being interrogated, said transducer follows one or more non-linear traces from a first-one of said points to a last one of said points;
• wherein all of said reflection signals represent acoustic impedance features present within said space so that, when a sealed package is interrogated by said transducer, the integrity of a seal defined in the sealed package can be inspected, and
• wherein said points are three-dimensionally varied within the microelectronic sample or sealed package.