Raymond Hayes

Ultraviolet And Extreme Ultraviolet Response Of Charge-Coupled-Device Detectors

We present results of a program to enhance the ultraviolet and extreme ultraviolet response of charge-coupled devices. The ultimate goal of our program is to develop a large format device with both high and stable quantum efficiency from 100 to 3000 A that can be used as a windowless imaging detector in a space environment. Ultraviolet quantum efficiency measurements have been made for several ion-implanted and laser-annealed test CCDs specially fabricated by Tektronix for this program. Quantum efficiencies as high as 22% at 2500 A , where the absorption depth in silicon is -55 A, have been observed in one such test CCD. Quantum efficiency measurements of standard back-illuminated RCA and Tektronix CCDs are also presented.

Dual-Channel Charge-Coupled Device For High Speed Signal Acquisition

The paper describes the design and development of a CCD shift register that can take analog samples of an electrical signal at rates up to 1 x 108 samples/s and provide temporary storage for 1024 samples. It is intended for operation in a fast-in, slow-out mode for capturing high speed electrical transients. The requirements of fast clocking and moderate clock driver power led to the choice of a serial-parallel-serial design. The CCD chip contains four storage arrays that form two differential channels. Differential operation provides good linearity. The two channels can be used independently or multiplexed for sampling at the highest rate. The CCD is of the buried-channel type and uses four-phase clocking on all registers. It is fabricated using a modified NMOS process, with two polysilicon layers to provide an overlapping transfer gate structure. Operating characteristics of the CCD are described, together with its behavior in an instrument environment. For optimum performance the CCD chip is mounted on a hybrid, together with clock driver ICs. Such devices are used in the signal acquisition section of a digital storage instrument that was developed recently.

Back-illuminated 1024 x 1024 quadrant readout imager: operation and screening test results

The Tektronix CCD Manufacturing Group has applied their thinning back surface enhancement and anti-reflection coating processes to produce a 1024 by 1024 chargecoupled device imager with high quantum efficiency (QE) from 350 to 1 100 nm. The TK1O24AB device designed for scientific imaging applications features low noise wide dynamic range excellent charge transfer efficiency and low dark current. The quad-output architecture permits the simultaneous readout of each quarter of the device reducing the time to read out the CCD to that of a 5 12 by 512 device. This paper summarizes the test results from several lots of TK 1024AB runs. The subjects covered include: QE the on-chip amplifier characteristics dark current measurement CTE and characterization of various defects. The paper will also describe the test hardware and procedures used to evaluate the performance of the devices.