Differential Etching Of Semiconductor Substrate Patents (Class 438/735)
  • Patent number: 6008138
    Abstract: A process for structuring a movable element out of a membrane region. A sacrificial layer and a sealing layer are applied to the underside of the membrane region. Following removal of the sacrificial layer, sealing layer forms a limit stop and a seal for the movement of the movable element.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: December 28, 1999
    Assignee: Robert Bosch GmbH
    Inventors: Franz Laermer, Andrea Schilp
  • Patent number: 5990009
    Abstract: A structure and method of maximizing the volume of low dielectric constant material between adjacent traces of a conductive interconnect structure. A semiconductor structure includes a semiconductor substrate, a first insulating layer located over the semiconductor substrate, a conductive interconnect layer having a plurality of conductive traces located over the first insulating layer, and a patterned insulating layer located over the patterned interconnect layer. One or more trenches are formed in the upper surface of the first insulating layer. These trenches, which do not extend completely through the first insulating layer, are located between adjacent traces of the interconnect layer. A dielectric material having a low dielectric constant is located in these trenches, and between adjacent traces of the patterned interconnect layer. The trenches advantageously maximize the volume of low dielectric constant material which is located between the traces.
    Type: Grant
    Filed: February 25, 1997
    Date of Patent: November 23, 1999
    Assignee: Integrated Device Technology, Inc.
    Inventors: Cheng-Chen Hsueh, Shih-Ked Lee, Chuen-Der Lien
  • Patent number: 5989445
    Abstract: Microchannels for conducting and expelling a fluid are embedded in a surface of a silicon substrate. A channel seal is made of plural cross structures formed integrally with the silicon substrate. The cross structures are arranged sequentially over each channel, each cross structure having a chevron shape. The microchannel is sealed by oxidizing at least partially the cross structures, whereby the spaces therebetween are filled. A dielectric seal which overlies the thermally oxidized cross structures forms a complete seal and a substantially planar top surface to the silicon substrate. The dielectric seal is formed of a low pressure chemical vapor deposition (LPCVD) dielectric layer. The channel is useful in the production of an ink jet print in head, and has a polysilicon heater overlying the dielectric seal. A current passing through the heater causes a corresponding increase in the temperature of the ink in the microchannel, causing same to be expelled therefreom.
    Type: Grant
    Filed: June 17, 1998
    Date of Patent: November 23, 1999
    Assignee: The Regents of the University of Michigan
    Inventors: Kensall D. Wise, Jingkuang Chen
  • Patent number: 5980763
    Abstract: A flat panel display or other large-area electronic device comprises at least one TFT (T1;T2) having a crystalline channel region (1) and amorphous edge regions (13) adjacent side-walls (12) of the TFT island (11). The TFT is fabricated by steps which include:(a) depositing on substrate (10) a thin film (11') of amorphous semiconductor material to provide the semiconductor material,(b) removing areas of the thin film (11') to form the side walls (12a, 12b) of each island (11),(c) forming a masking pattern 20 over the edge regions (13a, 13b) preferably on an insulating film 22, and(d) directing a laser or other energy beam (50) towards the islands (11) and the masking pattern (20) to crystallise the un-masked semiconductor material for the crystalline channel region (1), while retaining amorphous semiconductor material adjacent the side walls (12a, 12b) where the edge regions (13a, 13b) are masked from the energy beam (50) by the masking pattern (20). The resulting device structure has e.
    Type: Grant
    Filed: May 30, 1997
    Date of Patent: November 9, 1999
    Assignee: U.S. Philips Corporation
    Inventor: Nigel D. Young
  • Patent number: 5976980
    Abstract: A method and an apparatus providing a mechanical probe structure through the back side of an integrated circuit die. In one embodiment, semiconductor substrate is thinned from the back side of the integrated circuit die above a probe target. The probe target is then exposed and a thin insulating layer is formed over the exposed probe target and the nearby semiconductor substrate. The thin insulating layer provides electrical isolation between the exposed probe target and the bulk semiconductor substrate. The thin insulating layer also provides a base insulating platform for a probe pad that is subsequently deposited. After the insulating layer is formed over the exposed probe target and the nearby semiconductor substrate, the probe target is re-exposed through insulating layer such that a probe pad may be deposited over the probe target to provide electrical contact to the original probe target as well as provide a probe pad for mechanical probing purposes from the back side of the integrated circuit die.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: November 2, 1999
    Assignee: Intel Corporation
    Inventors: Richard H. Livengood, Paul Winer, Valluri R. M. Rao
  • Patent number: 5972232
    Abstract: Disclosed is a micromirror for a hybrid optoelectronic integrated circuit, a method for manufacturing the same, a micromirror-photodetector assembly and an assembly of hybrid optoelectronic integrated circuit for receiving light. The micromirror the present invention comprises a silicon substrate and at least one V-shaped groove formed in the silicon substrate and the V-shaped groove has an inclined surface reflecting light emitted from an optical waveguide to a photodetector. The alignment of the photodetector and the optical fibers is achieved without an additional attachment equipment, by inserting the optical fibers into the V-groove.
    Type: Grant
    Filed: December 3, 1997
    Date of Patent: October 26, 1999
    Assignees: Electronics and Telecommunications Research Institute, Korea Telecom
    Inventors: Sang Hwan Lee, Nam Hwang, Min Kyu Song, Hee Tae Lee, Kwang Eui Pyun
  • Patent number: 5970344
    Abstract: A channel layer is formed in a surface of a semiconductor substrate, and a plurality of trenches are formed in the surface of the semiconductor substrate, the trenches being deeper than the channel layer. Then, gate electrodes are formed in the trenches, respectively, after which body layers are formed between the trenches and source layers are formed adjacent to the trenches.
    Type: Grant
    Filed: August 24, 1998
    Date of Patent: October 19, 1999
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hirotoshi Kubo, Eiichiroh Kuwako, Masanao Kitagawa, Hiroaki Saito
  • Patent number: 5955380
    Abstract: Disclosed are metal fuse structures and methods for making the same. The method includes forming the fuse structure from a metallization layer. Depositing a bottom oxide layer, that is an HDP oxide, over the fuse structure that is formed from the metallization layer. Depositing a doped oxide layer over the base oxide layer. Depositing a top oxide layer over the doped oxide layer. Etching through the top oxide layer. Detecting an increased level of a dopant species that is emitted when the doped oxide layer begins to etch. The method further includes terminating the etching when the increased level of dopant species is detected. Wherein at least the bottom oxide layer remains over the fuse structure that is formed from the metallization layer.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: September 21, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventor: Gill Yong Lee
  • Patent number: 5952247
    Abstract: A method for accessing a portion of an integrated circuit formed on top of a semiconductor substrate from the bottom of the semiconductor substrate. First, alignment marks are located which are approximately aligned to the integrated circuit. These alignment marks are then used in conjunction with a circuit diagram of the integrated circuit to determine the point on the bottom of the semiconductor substrate residing beneath the portion of the integrated circuit which the practitioner desires to access. Finally, an opening is etched into the bottom of the semiconductor substrate at this point.
    Type: Grant
    Filed: October 2, 1996
    Date of Patent: September 14, 1999
    Assignee: Intel Corporation
    Inventors: Richard H. Livengood, Paul Winer, Valluri R. Rao
  • Patent number: 5943582
    Abstract: The present invention discloses a method for forming DRAM stacked capacitors by utilizing a densified oxide layer as an etch-stop for the wet etching process of an upper oxide layer in forming a contact hole for the stacked capacitor and thus, eliminating the need of a silicon nitride etch-stop layer and the occurrence of numerous processing difficulties normally observed in such stacked capacitor forming process. The lower oxide layer can be formed by a BPTEOS chemistry while the upper oxide layer can be formed by an ozone-TEOS chemistry.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: August 24, 1999
    Assignee: Taiwan Semiconductor Manufacturing Co. Ltd.
    Inventors: Julie Huang, Shing-Long Lee
  • Patent number: 5939741
    Abstract: In one aspect, a plurality of layers are formed over a substrate and a series of first trenches are etched into a first of the layers in a first direction. A series of second trenches are etched into the first layer in a second direction which is different from the first direction. Collectively, the first and second trenches define a plurality of different substrate elevations with adjacent elevations being joined by sidewalls which extend therebetween. Sidewall spacers are formed over the sidewalls, and material of the first layer is substantially selectively etched relative to material from which the spacers are formed. Material comprising the spacer material is substantially selectively etched relative to the first material. In a preferred implementation, the etching provides a plurality of cells which are separated from one another by no more than a lateral width dimension of a previously-formed spacer.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: August 17, 1999
    Assignee: Micron Technology, Inc.
    Inventors: Darwin A. Clampitt, James E. Green
  • Patent number: 5933728
    Abstract: A process for fabricating bottom electrodes for storage capacitors of memory cell units of a DRAM is disclosed. The process employs the use of a protective dielectric layer that serves as an etching shield in the process of fabrication of the capacitor electrode. The HSG-Si layer that substantially increases the surface area of the capacitor electrode can be protected from etching damage, thereby avoiding short-circuiting phenomena found in the conventional fabrication processes. Improved data retention time capability of the DRAM memory cells can thus be obtained utilizing the fabrication process of the invention.
    Type: Grant
    Filed: April 3, 1998
    Date of Patent: August 3, 1999
    Assignee: United Semiconductor Corp.
    Inventor: Jhy-Jyi Sze
  • Patent number: 5928965
    Abstract: A method for dry-etching a silicon substrate by the use of a mask selectively formed on the silicon substrate, in which method a reaction product of dry etching is deposited, during dry etching, in a uniform thickness on the side wall of each groove formed in the silicon substrate by dry etching. In the inventive method, etching is conducted by using, as an etching gas, a mixed gas containing Cl.sub.2, HBr, O.sub.2 and He or a mixed gas contained Cl.sub.2, HBr and CO, under the conditions of an etching pressure of 0.02-0.05 Torr, a RF power density of 1.01-1.64 W/cm.sup.2 and a substrate temperature of 40-50.degree. C. With this method, the tapered sectional shape of each groove formed in the silicon substrate can be controlled easily and etching can be conducted at high reproducibility.
    Type: Grant
    Filed: August 11, 1997
    Date of Patent: July 27, 1999
    Assignee: NEC Corporation
    Inventors: Hideyuki Shoji, Takakazu Kusuki
  • Patent number: 5922623
    Abstract: Disclosed is a method selective of vapor phase etching for fabricating a semiconductor device having a refractory metal silicide electrode abutting a silicon oxide film on the surface or a semiconductor device having an AlGaAs layer, an electrode formed on the AlGaAs layer and a silicon oxide film on the surface of the semiconductor device. The method comprises a step of removing a portion of the silicon oxide film by a gas including a vapor of hydrogen fluoride. The method further uses a mixture of nitrogen gas including vapor of anhydrous hydrofluoric acid and a nitrogen gas including a vapor of H.sub.2 O, wherein the ratio of the nitrogen gas including the vaporized anhydrous hydrofluoric acid to the nitrogen gas including vapor of H.sub.2 O is less than 1.
    Type: Grant
    Filed: May 8, 1996
    Date of Patent: July 13, 1999
    Assignee: NEC Corporation
    Inventors: Hiroaki Tsutsui, Takao Matsumura, Hirokazu Oikawa, Masayuki Yokoi, Junichi Nakamura, Hiroyuki Sato, Jun Mizoe
  • Patent number: 5922621
    Abstract: A method for fabricating a quantum semiconductor device includes the steps of forming an etch pit of a triangular pyramid on a {111}A-oriented principal surface of a substrate having zinc blende structure by a dry etching process, and depositing semiconductor layers forming a quantum structure consecutively on the etch pit.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: July 13, 1999
    Assignee: Fujitsu Limited
    Inventor: Yoshiki Sakuma
  • Patent number: 5916821
    Abstract: A method for producing sublithographic etching masks for creating structured features in semiconductor products having a large scale of integration, includes applying lines that are orthogonal to one another in successive steps with the aid of the spacer technique. Through the use of various etching steps, a grid of extremely small etching masks is obtained, which is formed by the intersection points of the lines. The size of the etching masks is determined by the layer thickness of the spacer layer, and not by the feature or structure size of the photographic technique.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: June 29, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventor: Martin Kerber
  • Patent number: 5916822
    Abstract: In order to facilitate resuming molecular beam epitaxy after etching a substrate or an epitaxial layer, the etching method is implemented in an ultra-high vacuum, and it consists in producing at least two simultaneous chemical beams converging towards the substrate or the layer, the beams being formed of substances, each of which is capable of reacting with elements of different types in the substrate or the layer so as to form volatile compounds. Application in particular to manufacturing photonic and optoelectronic components.
    Type: Grant
    Filed: August 8, 1996
    Date of Patent: June 29, 1999
    Assignee: Alcatel Optronics
    Inventors: Leon Goldstein, Jean-Louis Gentner, Philippe Jarry
  • Patent number: 5912187
    Abstract: A method of fabricating an integrated circuit device is described in which fluorine ions are implanted into the patterned photoresist and the exposed polysilicon layer prior to etching the polysilicon. The ion implantation minimizes the chemical reaction between the photoresist and etchant, thereby significantly reducing the formation of polysilicon etch delta, and also significantly reducing etch delta variation due to pattern density variations.
    Type: Grant
    Filed: June 10, 1997
    Date of Patent: June 15, 1999
    Assignee: Lucent Technologies Inc.
    Inventors: Joseph Paul Blasko, Robert John Griffin
  • Patent number: 5904570
    Abstract: The polymeric residues which remain after the plasma-enhanced subtractive etching of polycrystalline layers in reactive halogen-containing gases are removed by a combination ashing in oxygen gas and subsequent removal with an organic solvent.
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: May 18, 1999
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Sen-Fu Chen, Bao-Ru Yang, Wen-Cheng Chang, Heng-Hsin Liu
  • Patent number: 5895273
    Abstract: Decoupled plasma etching process used to make a protruding structure having vertical or near vertical sidewalls. The decoupled plasma etching process comprises the following steps:forming a mask on top of a semiconductor substrate defining the lateral size of the protruding structures to be formed in said substrate,feeding HCl, Cl.sub.2 and N.sub.2 into a plasma chamber to provide an ion plasma when applying source power,causing said ions to diffuse towards the substrate by applying a bias power such that the portions of said substrate not being covered by said mask are etched away, wherein the dosage of HCl, Cl.sub.2 and N.sub.2 is chosen such that newly formed portions of the sidewall surfaces are passivated by by-product of Si, Cl, and N.sub.2 and thus become protected from further being etched. The bias power is less than 70 Watts to ensure that the etching process is predominantly chemical.
    Type: Grant
    Filed: June 27, 1997
    Date of Patent: April 20, 1999
    Assignee: International Business Machines Corporation
    Inventors: Stuart M. Burns, Hussein I. Hanafi, Waldemar W. Kocon, Jeffrey J. Welser
  • Patent number: 5879572
    Abstract: A process for bulk micromachining a silicon wafer to form a silicon micromachined structure. The process involves the application of a protective film on one or more surfaces of the silicon wafer to protect metallization and circuitry on the wafer during the bulk micromachining process, during which a wet chemical etchant is employed to remove bulk silicon from a surface of the silicon wafer. The protective film is divinylsiloxane bisbenzocyclobutene (BCB), which has been found to be highly resistant to a wide variety of wet chemical etchants, and retains such resistant at elevated temperatures commonly preferred for bulk silicon etching. The degree to which this material is cured prior to etching is advantageously tailored to promote its resistance to the etchant and promote its adhesion to the silicon wafer.
    Type: Grant
    Filed: November 19, 1996
    Date of Patent: March 9, 1999
    Assignee: Delco Electronics Corporation
    Inventors: Joseph Keith Folsom, Johnna Lee Haller, Dan Wesley Chilcott
  • Patent number: 5877071
    Abstract: A method of removing an oxide mask during fabrication of semiconductor devices which includes providing a providing a III-V compound semiconductor substrate having a surface, the surface having a growth area and a masked area masked by an oxide film formed on the surface thereof. The oxide film is removed with a Trisdimethylamino group V compound.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: March 2, 1999
    Assignee: Motorola, Inc.
    Inventors: Kumar Shiralagi, Raymond K. Tsui
  • Patent number: 5871659
    Abstract: A process for dry etching a silicon substrate, in which a mask exposing a region of the surface of the silicon substrate is formed, and the exposed region is dry etched. The dry etching is performed with a gas mixture including chlorine or a chlorine-containing gas, an oxygen-containing gas, and a fluorine-containing gas in which a ratio of a flow rate of oxygen gas to a flow rate of chlorine gas, O.sub.2 /Cl.sub.2, is selected to be from 0.6 to 3. The gas mixture may also contain a fluorine-containing gas and helium. Preferably, the gas mixture excludes carbon-containing gases. The dry etching process allows for an increased etch rate, as well as a high etch selectivity compared to that of SiO.sub.2 gas. The trench formed in the substrate by this process can be made of a larger depth with high reproducibility and good configuration. The sidewall profile angle of the trench is maintained slightly tapered, with a sidewall profile angle of approximately 90 degrees.
    Type: Grant
    Filed: June 18, 1996
    Date of Patent: February 16, 1999
    Assignee: Nippondenso Co., Ltd.
    Inventors: Yoshikazu Sakano, Kenji Kondo, Hajime Soga, Yasuo Ishihara, Yoshifumi Okabe
  • Patent number: 5871870
    Abstract: A mask and a method for forming a mask on a surface of an underlying layer of material used in semiconductor device manufacturing. The mask is a mixture of mask particles and spacer particles. The spacer particles space the mask particles apart from one another to control the distance and the uniformity of the distribution of mask particles across the surface of the underlying layer. The spacer particles and mask particles have different physical properties that allow the spacer particles to be selectively removed from the surface of the underlying layer. The spacer particles are preferably removed from the surface of the underlying layer by selectively etching the spacer particles from the underlying layer. After the spacer particles are removed from the underlying layer, the mask particles remain on the underlying layer to provide spaced apart mask elements on the surface of the underlying layer.
    Type: Grant
    Filed: August 19, 1997
    Date of Patent: February 16, 1999
    Assignee: Micron Technology, Inc.
    Inventor: James J. Alwan
  • Patent number: 5869400
    Abstract: The present invention provides a method for dry-etching a solid surface with a gaseous bismuth halide compound, which permits achivement of a simple and perfect dry-process for manufacturing of electoric devices, quantum devices etc., giving a high reproducibility.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: February 9, 1999
    Assignee: Research Development Corporation of Japan
    Inventors: Tadaaki Kaneko, Takaaki Kawamura
  • Patent number: 5853601
    Abstract: A top-via etch technique for forming dielectric membranes for thin film devices, the dielectric membrane being deposited on the upper planar surface of the substrate. After the thin film device is formed on the dielectric membrane, a photoresist etch mask is deposited on the entire upper planar surface of the substrate, including the thin film structure. Vias are formed through the dielectric membrane and the protective photoresist etch mask to expose the upper planar surface of the substrate along opposite first and second ends of the thin film device. The upper planar surface of the substrate is isotropically etched using a reactive ion etching technique for example, to form air gaps beneath the dielectric membrane. The etching process may be carried out in etch segments of predetermined intervals, each followed by a cool down period of a prescribed interval.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: December 29, 1998
    Assignee: Northrop Grumman Corporation
    Inventors: Silaipillayarputhur V. Krishaswamy, William F. Valek, Thomas M. Valko, Curtis E. Milton, Jr., Joel F. Rosenbaum
  • Patent number: 5837616
    Abstract: In a dry etching method of aluminum (Al) alloy film comprising the steps of (1) forming an alloy film of which a major component is Al on a semiconductor substrate, (2) forming a resist pattern on the alloy film, and (3) dry etching the alloy film using the resist pattern as a mask with etching gas to which ammonia gas is added, a flow rate of the ammonia gas being set at between not less than half of a flow rate of the etching gas and not more than the flow rate of the etching gas. Improved fine pattern dry etching of Al alloy including Si and Cu is achieved.
    Type: Grant
    Filed: January 22, 1997
    Date of Patent: November 17, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Michinari Yamanaka
  • Patent number: 5827783
    Abstract: A method of forming a capacitor that has improved charge storage capacity in a high density memory device that has shallow trench isolation regions and a capacitor produced by the method are provided. The method includes the step of forming an oxide spacer that consists of a plurality of oxide layers deposited by two alternating methods of thermal CVD and plasma CVD. After a contact hole is first etched by a plasma etching technique, the hole is again decoratively etched by an etchant such as hydrogen fluoride which has a high selectivity toward oxide layers formed by the plasma CVD method and a low selectivity toward oxide layers formed by the thermal CVD method. As a result, a corrugated side-wall of the contact hole is formed which affords the capacitor cell with an increased surface area leading to an improved charge storage capacity.
    Type: Grant
    Filed: August 23, 1996
    Date of Patent: October 27, 1998
    Assignee: Mosel Vitelic, Inc.
    Inventors: Liang-Choo Hsia, Thomas Chang
  • Patent number: 5811345
    Abstract: A new method for planarization of shallow trench isolation is disclosed by the wet etching and plasma etching, due to the surface sensitivity of SACVD O.sub.3 -TEOS that depends on substrate. The method described herein includes a pad oxide layer, a silicon nitride layer, and a doped polysilicon oxide layer formed on a silicon substrate. A shallow trench is formed by photolithography and dry etching process to etch the doped polysilicon oxide layer, the silicon nitride layer, the pad oxide layer, and the silicon substrate. A SACVD O.sub.3 -TEOS layer is subsequently formed on the on the doped polysilicon oxide layer and filling into the trench, the deposition rate of the ozone-TEOS layer on the doped polysilicon oxide layer is slower than the deposition rate of the ozone-TEOS layer on the silicon wafer, the wet etching rate of the ozone-TEOS layer on the doped polysilicon oxide layer is faster than the etching rate of the ozone-TEOS layer on the silicon wafer.
    Type: Grant
    Filed: September 18, 1997
    Date of Patent: September 22, 1998
    Assignee: Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventors: Chen-Hua Yu, Syun-Ming Jang Jang
  • Patent number: 5772905
    Abstract: A lithographic method and apparatus for creating ultra-fine (sub-25 nm) patterns in a thin film coated on a substrate is provided, in which a mold having at least one protruding feature is pressed into a thin film carried on a substrate. The protruding feature in the mold creates a recess of the thin film. The mold is removed from the film. The thin film then is processed such that the thin film in the recess is removed exposing the underlying substrate. Thus, the patterns in the mold is replaced in the thin film, completing the lithography. The patterns in the thin film will be, in subsequent processes, reproduced in the substrate or in another material which is added onto the substrate.
    Type: Grant
    Filed: November 15, 1995
    Date of Patent: June 30, 1998
    Assignee: Regents of the University of Minnesota
    Inventor: Stephen Y. Chou
  • Patent number: 5753539
    Abstract: A permanently alterable, i.e., customizable, integrated circuit has a fuse element and contact pad, and windows extending above the same through an insulative layer. The contact pad window extends down to and exposes the contact pad. The fuse element window terminates just short of the fuse element so that the fuse element remains covered by a thin layer of insulative material. The fuse element and the contact pad reside in a common plane of the substrate and thus can be formed together using a single photolithographic transfer step. Windows of different depth are created above the fuse element and contact pad in a single etching step by providing at least one narrow width etching pattern resist aperture above the fuse element. This slows the etch rate at the fused element relative to that at the contact pad, due to a microloading effect.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: May 19, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Motoya Okazaki
  • Patent number: 5726085
    Abstract: A storage node 64 of a capacitor having increased charge storage capacity and a method for forming thereof. A doped polysilicon region 68 is formed. A thin layer of hemispherical grain polysilicon 70 is deposited over the doped polysilicon region 68. The doped polysilicon region 68 and the thin layer of hemispherical grain polysilicon 70 are etched using an etch chemistry that etches the doped polysilicon region 68 faster than the thin layer of hemispherical grain polysilicon 70 to increase the surface area of an upper surface 66 of the storage node 64.
    Type: Grant
    Filed: March 9, 1995
    Date of Patent: March 10, 1998
    Inventors: Darius Lammont Crenshaw, Rick L. Wise, Jeffrey McKee
  • Patent number: 5667941
    Abstract: Herein disclosed is an exposure technology for a semiconductor integrated circuit device which has a pattern as fine as that of an exposure wavelength. The technology contemplates to improve the resolution characteristics of the pattern by making use of the mutual interference of exposure luminous fluxes.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 16, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihiko Okamoto, Noboru Moriuchi
  • Patent number: RE36006
    Abstract: A metal selective polymer removal process is disclosed which prevents metal lift-off for use especially suited for ULSI fabrication.
    Type: Grant
    Filed: October 31, 1996
    Date of Patent: December 22, 1998
    Assignee: FSI International, Inc.
    Inventors: Brynne K. Bohannon, Daniel J. Syverson