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The disorder formation in quartz crystals by implantation of He+, B+, and Ar+ ions at room temperature is investigated by Rutherford‐backscattering spectrometry (RBS). The efficiency of the process of damage production is strongly dependent on the energy deposition mechanism and the degree of disorder. Three characteristic stages of defect formation are found in dependence on nuclear deposited energy density Gn: (I) Point defects are produced at Gn ≦ 1 × 1020 keV/cm3. (II) Amorphous microregions are generated up to the formation of a quasi amorphous layer (termed “RBS‐amorphous”) at Gn ≅ 2.5 × 1020 keV/cm3. (III) Further structural changes occur in RBS‐amorphous layers at larger Gn values. Disorder formation due to electronic processes is possible, but only in predamaged quartz, and at a very low efficiency.

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BYQuartz crystals (Z-cuts) are implanted with Ar+ (150 keV) and He+ (35 keV) ions a t room temperature. The annealing behaviour of the radiation damage between 300 and 1370 K is investigated by Rutherford backscattering spectrometry (RBS). Three stages with different thermal stability of the defects are found: 1. Simple defects produced a t nuclear deposited energy densities Q, 5 1 x 1020 keV cm-S can be completely annealed a t 770 K. 2. Amorphized microregions generated between Q, = 1 x 10eo keV om-3 and 2.5 x 1020 keV om-8 fully recrystallize at 1270 K. 3. RBS-amorphous layers formed a t Q, 2 2.5 x 1020 keV cm-3 cannot be annealed. Quarzkristalle (Z-Schnitte) werden mit Ar+ (150 keV)-und He+ (35 keV)-Ionen bei Raumtemperatur implantiert. Das Ausheilverhalten der eneugten Strahlenschiden wird im Temperaturbereich zwischen 300 und 1370 K mittels Weitwinkel-Rutherfordstreuung (RBS) untersucht. Drei Bereiche mit unterschiedlicher thermischer Stabilitit der Defekte konnen nachgewiesen werden: 1. Einfache Defekte, die bei einer Dichte der uber nukleare Prozesse deponierten Energie Q, 1 x 1020 keV cm-S eneugt werden, heilen bei 770 K vollstindig aus. 2. Amorphe Mikrobereiche, die bei a, = 1 x 1020 keV cm-3 bis 2,5 x 1020 keV cm-s entstehen, rekristallisieren bei 1270 K. 3. RBS-amorphe Schichten, die bei Q, 2 2,5 x 1020 keV om-3 gebildet werden, lassen sich nicht ausheilen.

A model of damage formation in LiNbO3 by N+ (150 keV, 300 K)‐implantation is discussed including the results of RBS, volume expansion, and refractive index investigation of simultaneously implanted, X‐, Y‐ and Z‐cuts. For dose values D italicN + ≦ 1 × 1015 cm−2 most of the displaced Nb atoms occupy vacant octahedral lattice sites. Because of the high stability of the crystal structure in the c‐direction, a complete amorphization of the implanted LiNbO3 layers is not attained even with D italicN + = 4 × 1016cm−2.