Joe Beach
CSM Physics Department, Meyer Hall, Room 447
1523 Illinois Street, Golden CO 80401-1887
Phone: 303-384-2176
Fax: 303-273-3919
E-mail: jbeach@mines.edu

Joe Beach CSM Physics logo

REMRSEC Semiconductor Processing Facilities

The Renewable Energy Materials Research Science and Engineering Center (REMRSEC) has numerous facilities for the growth, processing, and characterization of semiconductors. This page will focus on some of the REMRSEC thin film growth capabilities.

The three primary thin film deposition tools that the REMRSEC has are a PECVD cluster tool located in Hill Hall 302, a RF/DC sputter deposition machine located in Meyer Hall 425, and a thermal evaporator located in Meyer Hall 425.

PECVD Cluster Tool

REMRSEC Cluster Tool The REMRSEC's cluster tool was manufactured by MV Systems. It presently has three modular process zones, and can be expanded to have as many as eight. It can grow on substrates up to 4"x4" (nominal). It uses a robust, low temperature radiant heating design to heat the substrates up to 450 C. It is equipped with a 100 W RF power supply to generate plasma.

The cluster tool is currently supplied with hydrogen, argon, sulfur hexafluoride, and silane. This allows it to grow Si nanoparticles, Si nanowires, nanocrystalline Si, and amorphous Si. We plan to add ammonia, germane, phosphine, and diborane in the coming weeks and months. This will allow the growth of doped Si, Ge, SiN, and SiGe materials.

Due to the pyrophoric and toxic natures of the process gases that are used in the cluster tool, its usage is restricted to trained staff and graduate students who need its growth capabilities on a long term basis. In addition, the doors to Hill Hall 302 and Hill Hall 306 must remain closed and locked to restrict access to the plumbing and equipment containing the hazardous gases. Besides being a good idea, this is a legal requirement for use of these gases.

We keep several different log books to track the use and maintenance of the cluster tool and its associated hardware and gases. Copies of the log sheets are available here so that PECVD cluster tool users can print them to add to the log books when they are needed. They are provided in Open Document Format (.odt) and Portable Document Format (.pdf). Open Document Format can be used by a variety of word processing programs. Openoffice is a good choice. Portable Document Format is viewable and printable by a variety of PDF viewers.

RF/DC Sputter Machine

REMRSEC Sputter Machine The REMRSEC's sputter machine is an Orion-4 purchased from AJA International. It is an "all manual" machine, which reduced its cost and also forces our students to learn more about how the machine actually works so they operate it. It has four 2" sputter guns integrated into its base plate at a fixed tilt. The sputter guns are magnetrons with water cooling and flip-lid style shutters that allow the plasma to be struck and stablilized prior to film deposition. The argon sputter gas enters the chamber through ports in the base of each sputter gun "chimney", allowing the guns to have Ar flow even when the shutters are closed.

The machine has two 300 W RF power supplies and two 500 W DC power supplies. These can be connected to any of the sputter guns or to the substrate holder. Multiple power supplies can be run simultaneously, allowing for codeposition or reactive deposition.

Samples are load locked into the deposition chamber by a magnetically coupled linear transport arm. The substrate platen can accommodate up to 4" diameter round substrates. The substrate holder quite advanced; it can rotate at up to 20 rpm for increased film uniformity, it can be biased with RF or DC potentials, it can be raised or lowered over a 5 cm span, and it can be heated to 850 C.

The sputter guns are designed to accept targets up to 0.25" thick. Materials we have sputterd include aluminum, chromium, titanium, copper, zinc oxide, indium tin oxide, and zinc telluride.

Thermal Evaporator

REMRSEC Thermal Evaporator The thermal evaporator is our "workhorse" general purpose thin film deposition system. It was originally manufactured by Denton, but it has been heavily modified over the years. It is a diffusion pumped bell jar chamber with three evaporator stations in the base plate. The chamber can reach pressures in the low 10-6 range after 1-2 hours of pumping. The chamber does not presently have a liquid nitrogen cold trap because its original trap developed a vacuum leak. A new or repaired cold trap would likely reduce the chamber's base pressure to the low 10-7 range.

A single high current AC power supply can be switched between the three evaporation sources. The maximum current is presently 100 A, although a wiring and switch upgrade could increase that to 200 A. We evaporate material from coiled tungsten filaments, tungsten dimple boats, or quartz crucibles depending on the material characteristics.

The evaporator is presently configured for room temperature substrates. The film growth rate and thickness can be monitored with a quartz crystal monitor. We have used this machine to deposit thin films of materials such as aluminum, gold, copper, silver, manganese, indium, and lithium fluoride.

We keep a log book to track the use and maintenance of the evaporator. Copies of the log sheets are available here so that evaporator users can print them to add to the log book when they are needed. They are provided in Open Document Format (.odt) and Portable Document Format (.pdf). Open Document Format can be used by a variety of word processing programs. Openoffice is a good choice. Portable Document Format is viewable and printable by a variety of PDF viewers.