Single-etch grating couplers provide efficient light coupling from optical fibers to photonic waveguides while having a very low fabrication complexity. Here, the use of a coupling coefficient profile solution permits an efficient optimization of the grating apodization profile and yields a simulated -4.8 dB coupling at 1550 nm. A very compact way to reduce back-reflections by up to 8 dB, by inserting a simple anti-reflective section, is also numerically investigated. Some proximity effects and minimum features of the 248 nm deep-ultraviolet lithography had a detrimental effect on the fabricated designs and the best experimental results were -7.5 dB. Nonetheless, these gratings, requiring a single-etch step fabrication process, should be useful when using e-beam prototyping.