Abstract: Trenches in which to form a back side isolation structure for an array of CMOS image sensors are formed by a cyclic process that allows the trenches to be kept narrow. Each cycle of the process includes etching to add a depth segment to the trenches and coating the depth segment with an etch-resistant coating. The following etch step will break through the etch-resistant coating at the bottom of the trench but the etch-resistant coating will remain in the upper part of the trench to limit lateral etching and substrate damage. The resulting trenches have a series of vertically spaced nodes. The process may result in a 10% increase in photodiode area and a 30-40% increase in full well capacity.

Abstract: A headphone having a headband and two acoustic transducers disposed at two ends of the headband is disclosed. Each acoustic transducer includes a baffle plate installed with a speaker, a spacer, a vent and an acoustic modulator. The baffle plate and speaker divide the acoustic transducer into a front and a back chamber. The front chamber is configured for communicating with a user's ear. The spacer is disposed behind the speaker to divide the back chamber into a first back chamber and a second back communicated with each other. The vent is disposed in a back wall of the acoustic transducer to communicate the first back chamber with outside. The first acoustic modulator is disposed between the front and second back chambers. The headphone modulates resonance frequency at low frequency bands through the acoustic modulator.

Abstract: A headphone having a headband and two acoustic transducers disposed at two ends of the headband is disclosed. Each acoustic transducer includes a baffle plate installed with a speaker, a spacer, a vent and an acoustic modulator. The baffle plate and speaker divide the acoustic transducer into a front and a back chamber. The front chamber is configured for communicating with a user's ear. The spacer is disposed behind the speaker to divide the back chamber into a first back chamber and a second back communicated with each other. The vent is disposed in a back wall of the acoustic transducer to communicate the first back chamber with outside. The first acoustic modulator is disposed between the front and second back chambers. The headphone modulates resonance frequency at low frequency bands through the acoustic modulator.