Crystal four-inch

The growth technology of four-inch crystal along [OlTl], which is the optimal orientation for the wafer fabrication for SAW device use, is optimized by elucidating... 

Fig. 15.21 Distribution of SAW velocity on wafers made from (a) the top and (b) bottom portion of the four-inch crystal. The velocity is represented by a gray scale. The average velocity and standard deviation of...

Nal(Tl) crystals. The sample to be counted is mounted between Mylar sheets on a 1/4-inch thick X 5-inch diameter plastic ring. This system is presently used with a four quadrant, multiplexed, 4096-channel, multidimensional analyzer. The multidimensional y spectrum in coincidence with the proportional counter events is recorded in one quadrant, and the anticoincident multidimensional y spectrum is recorded in another quadrant thus, no data are lost. The various background y spectra obtained with this detector assembly are compared in Figure 12. The y-y coinci-... 

The crystal element consisted of a sandwich of four tourmaline disks mounted on a steel shank. (Crystal elements of this type are available from Crystal Research, Inc., 40 Concord Lane, Cambridge, Mass.) This element, supported by an axial shaft, was held in a 6-inch length of /4-inch diameter brass tube (standard %-inch pipe). The upper edge of the element was about 1 mm. below the rim of the tube. The tube was filled under vacuum with a warm mixture of medicinal mineral oil and petroleum jelly, which set into a soft gel on cooling. The gage unit was fastened by a threaded joint in the wall of the detonation tube, with the rim of the gage tube flush with the inside of the detonation tube. 

---