Image charge detection statistics relevant for deterministic ion implantation

Abstract

Image charge detection is a non-perturbative pre-detection approach for deterministic ion implantation. Using low energy ion bunches as a model system for highly charged single ions, we experimentally studied the error and detection rates of an image charge detector setup. The probability density functions of the signal amplitudes in the Fourier spectrum can be modelled with a generalised gamma distribution to predict error and detection rates. It is shown that the false positive error rate can be minimised at the cost of detection rate, but this does not impair the fidelity of a deterministic implantation process. Independent of the ion species, at a signal-to-noise ratio of 2, a false positive error rate of 0.1% is achieved, while the detection rate is about 22%.

Charge‐Assisted Engineering of Color Centers in Diamond

“…The method is still under development but promising results were already achieved. [44] 3. Impurity-Vacancy Defect Formation…”

Deterministic Shallow Dopant Implantation in Silicon with Detection Confidence Upper‐Bound to 99.85% by Ion–Solid Interactions

“…This has motivated the development of donor spin qubits in silicon, [8] starting from the proposal of Kane. [9] The electron [10] and the nuclear [11] spin of a single 31 P donor, ionimplanted in a silicon CMOS device, have proven to be outstanding qubits, with coherence times exceeding 0.5 s (electron) or 30 s (nucleus). [12] Singlequbit error rates are in the 0.01-0.03% range, [13,14] thus addressing requirement (ii) at the 1qubit level.…”

“…[15] This follows the wellestablished prec edent of using ion implantation to introduce a wellcalibrated density of dopants in classical silicon CMOS devices. [19] We make use of the fact that ionimplanted 31 Patoms in silicon at sparse concentrations can be converted to electricallyactive sub stitutional donors with ≈100% yield [20][21][22] and sub2 nm diffu sion. [23] This is a present advantage of our donor qubit platforms compared to other spinbased systems in the solid state.…”

“…[24] A key benefit of ion implantation is that any groupV donor can be introduced into silicon substrates, allowing a diverse range of applications. The focus of the present work is 31 P, the simplest system, offering spin1/2 nuclear and electron spin qubits. [10][11][12] Other donors of interest include 123 Sb, which has a nuclear spin I = 7/2 that can encode error protected logical qubits [25] and can be controlled by local electric fields.…”

“…These include the nonstochastic coldion trap source [30] where arrays of single ions are assembled before implantation and adaptations of ubiquitous stochastic ion source systems. These include the flyby image charge detector, [31] where the incidence of a single ion is detected prior to implantation, and strategies where the ion is detected upon implantation. An early example of the latter strategy employs the ionimpactinduced burst of secondary electrons escaping from the substrate surface to signal singleion implants.…”