Porous silicon patterned by hydrogen ion implantation

An integrated CMOS sensing chip for NO2 detection

“…If the chip is not protected by a suitable masking layer during the etching steps (apart from the sensor area) HF molecules will lead to the etching of oxides and metals outside the sensor region, thus damaging the electronic circuits integrated on the chip. Even if a number of dielectric and conductive materials have been proposed in literature for selective PS formation [31][32][33][34], the most suitable one is the photoresist, as it is commonly used as a masking layer in microelectronic technologies and it is HF-resistant. However, while thin photoresist layers can be efficiently used for oxide removal by means of BHF etching solutions, such layers cannot be easily employed for electrochemical etching of silicon.…”

Porous Silicon Characterization and Application: General View

“…Another promising approach to PSi patterning based on ion implantation is the use of the mask formed by hydrogen ion implantation over p-type silicon substrate, combined with rapid thermal annealing (RTA) (Galeazzo et al 2001;Dantas et al 2003Dantas et al , 2004. Such a procedure can create a buried high resistivity layer due to damaging of silicon lattice and electrical neutralization of boron donor sites by hydrogen (Pankove and Johnson 1991), and thus inhibit electrochemical etching in this area.…”

Optimized plasma-polymerized fluoropolymer mask for local porous silicon formation

“…In the literature, different kinds of HF resistant materials have been tested and proposed as a masking layer for deep PS formation. [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] Among them, silicon nitride (Si x N y ), 15,16 bilayer of polycrystalline silicon/silicon dioxide, 18,22 or tri-layer stack of poly-Si/Si x N y /SiO 2 12 are the most widely used masking materials due to the maturities of deposition techniques and the compatibility with current silicon processing. However, the common drawback of all these masking materials is the complicated post-etching mask removal procedures when bare silicon surface is ultimately required.…”