Precise in situ etch depth control of multilayered III−V semiconductor samples with reflectance anisotropy spectroscopy (RAS) equipment

• Ann-Kathrin Kleinschmidt,
• Lars Barzen,
• Johannes Strassner,
• Christoph Doering,
• Henning Fouckhardt,
• Wolfgang Bock,
• Michael Wahl and
• Michael Kopnarski

Beilstein J. Nanotechnol. 2016, 7, 1783–1793, doi:10.3762/bjnano.7.171

• sample in order to make RAS control possible. Keywords: broad area semiconductor lasers (BAL); dry-etch monitoring (RIE); precise etch depth control; reflectance anisotropy spectroscopy (RAS); III–V semiconductors; Introduction Reflectance anisotropy/difference spectroscopy (RAS/RDS) [1][2][3][4][5] is

• our case, precise etch depth control is essential. To fabricate the described laser, a semiconductor layer sequence (sample of type B) is masked with the desired stripe pattern and the unmasked regions are deeply etched with reactive ion etching (lithographic process I, see Figure 5a). Here a soft