The hetrojunction amorphous n+(a-Si)/n-i-p(a-SiC)/i-n+(a-Si) phototransistor with high gain (&#8764;40) and high speed (&#8764;10&#181;s)
In this report, a hetrojunction amorphous Si-SiC barrier transistor (a-HJBT) was successfully fabricated which revealed high gain (∼40) and high speed (∼10µs). The homojunction amorphous silicon bulk barrier phototransistor has been reported to be a high gain (∼12) and high speed (∼30µs) photosensing device. In this report, a significant improvement has been achieved by making a hetrojunction structure between the emitter and the base by a structure of n<sup>+</sup>(Si)/n-i-δp<sup>+</sup>(SiC) which is in contact with the i-n<sup>+</sup>(Si) collector layers. The structure was successfully made by plasma enhanced chemical vapor deposition (PECVD) on a glass substrate.
Contact-Type Linear Sensor Using Amorphous Si Diode Array
A contact-type linear sensor using amorphous Si diodes as photodetectors has been developed. The sensor structure can largely reduce the number of electrodes to be connected to the switching FETs and hence has an advantage of realizing a facsimile reader which is compact and easy to construct. The linear sensor developed is constructed with 256 pairs of In2O3/a-Si photodiodes and Pt/a-Si blocking diodes and this combination of two types of diodes has been found to yield high output signal. In this sensor structure, incident light is introduced to the photodiodes through a glass substrate in order to protect the photodetectors from contamination and scratching.
Local public health agency performance and community health status.
This study describes the results of an analysis of the relationship between local public health agency performance and health outcomes. Findings support the model that local public health agency performance affects community health status, and depending on the outcome, performance contributions vary. New hypotheses are offered that could help determine how system performance affects health outcomes.