Shallow Fresnel lens fabrication using grayscale lithography made by high energy beam sensitive mask (HEBS) technology and reactive ion etching

Tali Nachmias; Avi Ohayon; Shefer E. Meltzer; Meni Kabla; Elie Louzon; Uriel Levy

doi:10.1117/12.809376

23 February 2009 Shallow Fresnel lens fabrication using grayscale lithography made by high energy beam sensitive mask (HEBS) technology and reactive ion etching

Tali Nachmias, Avi Ohayon, Shefer E. Meltzer, Meni Kabla, Elie Louzon, Uriel Levy

Author Affiliations +

Proceedings Volume 7205, Advanced Fabrication Technologies for Micro/Nano Optics and Photonics II; 72050B (2009) https://doi.org/10.1117/12.809376
Event: SPIE MOEMS-MEMS: Micro- and Nanofabrication, 2009, San Jose, California, United States

Abstract

We describe the fabrication and the characterization of high efficiency Fresnel lenses by the use of gray scale lithography (GSL), followed by reactive ion etching (RIE) or deep reactive ion etching (DRIE) to transfer the pattern from the gray scale resist into the silicon substrate. Three versions of Fresnel lenses were fabricated, with height of 600nm, 1800nm and 5500nm. The desired lens height in silicon is determined from photoresist height and the selectivity of the etching process. A low selectivity DRIE process was developed in order to fabricated 1800nm and 5500nm Fresnel lenses. The 600nm Fresnel lens was fabricated using an RIE process because it requires a relatively slow etch rate and low selectivity, both could not be obtained by DRIE. According to the photoresist thickness developed in the gray scale lithography, an RIE process with a selectivity of 0.55 was required. We implement the DOE (design of experiment) method for finding the process parameters which gives the desirable selectivity and its tolerance which is crucial for determining the range of the Fresnel lens height. It was found that according to the selectivity tolerance, the Fresnel lens stands within ±10% tolerance of its height. Finally, we demonstrated the imaging of an object using the 600 nm lens.

Citation Download Citation

Tali Nachmias, Avi Ohayon, Shefer E. Meltzer, Meni Kabla, Elie Louzon, and Uriel Levy "Shallow Fresnel lens fabrication using grayscale lithography made by high energy beam sensitive mask (HEBS) technology and reactive ion etching", Proc. SPIE 7205, Advanced Fabrication Technologies for Micro/Nano Optics and Photonics II, 72050B (23 February 2009); https://doi.org/10.1117/12.809376

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available