Correlation between dislocation etch pits and optical absorption in CdGeAs2

Correlation between dislocation etch pits, carrier concentration and optical absorption in CdGeAs 2 grown by modified Vertical Bridgman method

“…In this four wafers, the EPD at the edge was more than 10 5 cm -2 . Usually, the typical radial EPD distribution had a "V" shape M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 6 which is similar to it reported for CdGeAs 2 crystal grown by HGF method [24], instead of the "Λ" shape in our experiment formerly. The "V" shape EPD distribution in CdGeAs 2 indicates that dislocations do not propagate from the spontaneous nucleation seed whose EPD was uniform distribution, and that this region has low strain.…”

“…And the interaction of dislocations with other types of defects in crystals has been thought to play some role in the electrical and optical properties. K. Nagashio et al focused on the influence of dislocation density and optical absorption at 5.5 µm, and discussed an improvement by alteration of the growth orientation [5,15,24]. Lihua Bai et al established a linear correlation between absorption at 5.5 µm and hole concentration [25,26].…”

Improving optical transparency in CdGeAs2 crystals by controlling crystalline defects

“…A growth system was set-up at Stanford by Nagashio et al [7] to grow crystals under carefully controlled conditions using the general horizontal gradient freeze methodology developed by Schunemann et al [11]. A goldcoated, two-zone, transparent furnace was used together with low-temperature gradients.…”

“…In photographs taken along the growth axis, both Feigelson and Route [5] and Schunemann et al [6] found two regions of widely different transparency separated by a sharp boundary. Nagashio et al [7] determined that this effect was related to the density and spatial distribution of dislocations in these crystals. They found that when boules were grown in the [1 1 2] direction, the radial and axial absorption uniformity was, as predicted, greatly improved.…”

Fragmentation of faceted dendrite in solidification of undercooled B-doped Si melts

“…In the crystal growth of Si, it is well known that the fluctuation in growth rate causes the segregation of dopant elements at the growth interface and forms the characteristic striped pattern called "striation." [14] If it can be assumed that striations are formed at the plateau stage, the inspection of the relationship between dendrite morphology and striation pattern should permit a distinction between the region solidified during recalescence and that solidified at the plateau stage.…”